WEBVTT - What is the maximum vacuum?

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<v Speaker 1>Hey, Daniel, do you enjoy doing housework?

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<v Speaker 2>There's something satisfying about it compared to the abstraction of research.

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<v Speaker 2>You know, you start doing dishes and then the dishes

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<v Speaker 2>are done.

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<v Speaker 1>Yeah, that's a cost and effect, right, basic law of

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<v Speaker 1>the universe. If you wash the dishes, they will presumably

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<v Speaker 1>be clean.

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<v Speaker 2>I wish that same thing applied to physics research. You know,

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<v Speaker 2>you do the physics research and the mysteries are unraveled.

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<v Speaker 2>Doesn't know what's happened that way.

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<v Speaker 1>Well, there's no guarantee in science.

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<v Speaker 2>How about you. Are you a fan of housework?

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<v Speaker 1>Uh? No, And yet I'm the person who does all

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<v Speaker 1>the dishes in my house. Well, actually the dishwasher doesn't,

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<v Speaker 1>but I assist the dishwasher. I'm the assistant dishwasher.

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<v Speaker 2>And are you a fan of vacuuming?

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<v Speaker 1>I'm not a huge fan.

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<v Speaker 2>No.

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<v Speaker 1>I mean, I think my vacuum has a big fan,

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<v Speaker 1>but I am not a fan of vacuuming.

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<v Speaker 2>I agree vacuuming totally sucks.

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<v Speaker 1>Hi. I'm Horium, my cartoonist and the author of all

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<v Speaker 1>ours great big Universe.

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<v Speaker 2>Hi. I'm Daniel. I'm a particle physicist and a professor

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<v Speaker 2>at U. See Irvine, and sometimes I feel like my

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<v Speaker 2>head contains a perfect vacuum.

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<v Speaker 1>You mean, like a perfect vacuuming machine or a perfect

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<v Speaker 1>lack of pressure.

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<v Speaker 2>You know how, sometimes you reach back into your mind

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<v Speaker 2>for a good idea and you just find nothing. On

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<v Speaker 2>the other hand, you know, maybe that means you're ready

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<v Speaker 2>to suck in a bunch of new information.

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<v Speaker 1>M I thought you were saying your brain sucks.

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<v Speaker 2>The creative process is a mystery to me.

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<v Speaker 3>You know.

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<v Speaker 2>Sometimes you reach back there and you find gold, and

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<v Speaker 2>other times you are just left empty handed.

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<v Speaker 1>It is pretty dusty inside of my head as well.

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<v Speaker 1>But anyways, welcome to our podcast, Daniel and Horror I

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<v Speaker 1>Explained Universe, a production of iHeartRadio.

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<v Speaker 2>In which we try to take the whole universe and

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<v Speaker 2>squeeze it into your brain, hoping that there's enough space

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<v Speaker 2>to contain all of its mysteries, all of its majesty,

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<v Speaker 2>all of its marvelous contents, including quantum particles, including black holes,

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<v Speaker 2>including neutron stars, including photons, and everything else that makes

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<v Speaker 2>this universe a wonderful, delicious and bizarre place to live.

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<v Speaker 1>That's right. It is science's job to dig down into

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<v Speaker 1>the dusty corners of the universe and polish off our

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<v Speaker 1>knowledge about how things work and why things are the

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<v Speaker 1>way they are.

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<v Speaker 2>And when scientists think about dust, we're not always just

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<v Speaker 2>thinking about it as an annoyance, something to get rid of. Instead,

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<v Speaker 2>we want to take the universe apart into its smallest pieces,

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<v Speaker 2>and so dust provides a very useful clue. What is

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<v Speaker 2>dust made out of? What happens when we break dust

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<v Speaker 2>open into smaller bits? Why is the universe so dusty? Anyway?

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<v Speaker 1>So we are actually technically all made out of star dust, right,

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<v Speaker 1>isn't that what the famous saying from Carl Sagan?

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<v Speaker 2>That is the famous saying. And you know it's mostly true.

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<v Speaker 2>All the heavier elements we were made of, at least

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<v Speaker 2>were composed in the hearts of stars out there, fusing

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<v Speaker 2>together the primordial hydrogen and helium created during the Big Bang.

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<v Speaker 2>But since a large part of our bodies are made

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<v Speaker 2>of hydrogen, part of us are actually Big Bang dust,

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<v Speaker 2>not just star dust.

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<v Speaker 1>I guess maybe since atoms are all made of the

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<v Speaker 1>same things, technically, like, it's just more and more dust,

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<v Speaker 1>kind of compounded dust that we're made out of.

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<v Speaker 2>Jorges Dusty theory of the Universe.

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<v Speaker 1>Now, does that mean that bunnies are also made out

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<v Speaker 1>of dust bunnies?

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<v Speaker 2>Or are dust bunnies made out of bunnies?

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<v Speaker 1>How about people named dusty? Would they also be made

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<v Speaker 1>out of star dust?

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<v Speaker 2>Star dust and bang dust? And while it's fun to

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<v Speaker 2>make these jokes, it's also really a fascinating mystery, like

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<v Speaker 2>what is all of this stuff? What is its fundamental nature?

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<v Speaker 2>Deep down? And that question is sitting inside a deeper, broader,

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<v Speaker 2>maybe even emptierestion, which is like, what is all of

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<v Speaker 2>this stuff sitting in? What happens to the universe if

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<v Speaker 2>you get rid of all the dust, you finally suck

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<v Speaker 2>it all away and reveal the nothingness? What is all

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<v Speaker 2>of that nothingness?

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<v Speaker 1>That's right? What is nothing? Is it nothing? Or is

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<v Speaker 1>nothing something?

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<v Speaker 2>Do we have nothing to say about it? And can

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<v Speaker 2>we anyway spin it into a forty five minute podcast?

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<v Speaker 1>No, let's just create an audio vacuum right now for

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<v Speaker 1>forty five minutes. Ready go.

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<v Speaker 2>That's actually a great analogy for today's podcast because even

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<v Speaker 2>in that quiet, pun free moment, there was not nothing.

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<v Speaker 2>There was something.

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<v Speaker 1>So today on the podcast, we'll be asking the question

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<v Speaker 1>what is a vacuum?

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<v Speaker 2>Now?

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<v Speaker 1>I imagine Daniel, you mean like a space vacuum, not

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<v Speaker 1>like a household vacuum.

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<v Speaker 2>I do love digging into the physics of everyday objects,

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<v Speaker 2>because it turns out there's always a surprising amount of

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<v Speaker 2>complicated physics that goes into like what is a mirror?

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<v Speaker 2>Or how does glass work? This kind of stuff is

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<v Speaker 2>super fun. But no, today, I want to talk about

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<v Speaker 2>the nothingness of the universe. What happens if you use

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<v Speaker 2>a vacuum to suck up all this stuff? What is

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<v Speaker 2>that vacuum? And philosophically, what does that mean about the

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<v Speaker 2>nature of reality?

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<v Speaker 1>Yeah, and I guess more fundamentally, does a vacuum exist?

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<v Speaker 1>Is it possible to actually have nothing in the universe?

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<v Speaker 2>Or is it possible to have multiple different vacuums or

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<v Speaker 2>vacuum a.

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<v Speaker 1>Or maybe more a trippy Is a vacuum something.

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<v Speaker 2>Or if a vacuum is something, maybe that's just what

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<v Speaker 2>we define as nothing as the most vacuum meist something.

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<v Speaker 1>Okay, now I'm getting nothing out of this.

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<v Speaker 2>I just invented a word vacuumist. Vacuumist, though it sounds

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<v Speaker 2>more like somebody who operates a vacuum. Maybe it's not

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<v Speaker 2>the best choice.

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<v Speaker 1>Well, that would be a vacuumer, wouldn't it be?

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<v Speaker 2>Not an expert in naming things over here?

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<v Speaker 1>Very clearly, But anyways, as usual, we were wondering how

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<v Speaker 1>many people out there had thought about this fundamental question

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<v Speaker 1>what is a vacuum and if they have any ideas

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<v Speaker 1>about whether it is something or nothing.

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<v Speaker 2>So thanks very much to everybody out there who answers

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<v Speaker 2>these questions for the podcast. And if you've been listening

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<v Speaker 2>for a while or even just a few weeks and

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<v Speaker 2>you'd like to throw your hat into the ring, everybody's welcome,

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<v Speaker 2>please write to me two questions at Danielandjorge dot com.

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<v Speaker 1>So think about it for a second. What do you

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<v Speaker 1>think a vacuum is? Here's what people have to say.

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<v Speaker 4>It sounds like the inside of my head when you

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<v Speaker 4>ask this question, But if I were to think of it,

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<v Speaker 4>vacuum is like a whiteboard with infinite possibilities, And when

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<v Speaker 4>something comes along, like a whiteboard marker, you can either

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<v Speaker 4>draw stuff on it or you can just raise stuff

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<v Speaker 4>on it.

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<v Speaker 1>It's just everything.

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<v Speaker 5>The vacuum would be space without any stuff in it,

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<v Speaker 5>like no atmosphere, but I think space always has some

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<v Speaker 5>stuff in it, so it's not really a true vacuum.

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<v Speaker 5>That's really all I know.

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<v Speaker 1>I'm pretty sure the vacuum is like space with all

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<v Speaker 1>its quantum fields, like at its resting state.

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<v Speaker 3>I can guess by what it says the vacuum is

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<v Speaker 3>not a vacuum cleaner, but the vacuum of space. What

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<v Speaker 3>causes it is actually a good question. I don't know.

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<v Speaker 3>Maybe it's something related to dark energy and expansion, but

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<v Speaker 3>probably not.

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<v Speaker 4>I think vacuum is the definition, the theoretical definition of

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<v Speaker 4>the absence of matter in a given space.

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<v Speaker 6>I think vacuum quite literally means emptiness or absence of stuff. Now,

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<v Speaker 6>if you have a bottle, you remove everything from it,

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<v Speaker 6>then you have a vacuum. But I think that's pretty ideal.

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<v Speaker 2>I don't think you can actually remove everything from a bottle.

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<v Speaker 6>Vacuum is the absence of matter, but I know that

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<v Speaker 6>it doesn't mean it's empty, and there are lots of

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<v Speaker 6>quantum craziness going around in what we traditionally call vacuum.

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<v Speaker 6>So I'm looking forward for your guys to explain it.

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<v Speaker 1>All right, A lot of interesting answers here. Someone got

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<v Speaker 1>kind of technical talking about fields and resting states, the

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<v Speaker 1>absence of matter.

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<v Speaker 2>M m lots of really cool answers here that explore

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<v Speaker 2>really the wide spectrum of possibilities for what nothing is.

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<v Speaker 1>Yeah, I guess you could define it in several ways, right,

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<v Speaker 1>like absence of matter or absence of energy, or absence

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<v Speaker 1>of quantum field maybe.

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<v Speaker 2>Yeah, And we will tear all of that apart on

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<v Speaker 2>the podcast today.

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<v Speaker 1>Well, let's dig into it, Daniel. How does physicists define

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<v Speaker 1>what a vacuum is?

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<v Speaker 2>So, the definition of a vacuum, from the point of

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<v Speaker 2>view of physics and especially quantum field theory, is space

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<v Speaker 2>with no particles in it. Essentially space as empty as

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<v Speaker 2>possible from energy. If you can stuck all the energy out,

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<v Speaker 2>including the matter, and relax space down to its lowest

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<v Speaker 2>energy state, that's what we consider a vacuum.

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<v Speaker 1>Now, how is it different than the concept of space itself.

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<v Speaker 1>Is space the vacuum or can space be a vacuum?

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<v Speaker 2>Well, there's the difference between space and sort of empty space.

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<v Speaker 2>Space itself doesn't have to be a vacuum. Like at

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<v Speaker 2>the heart of the Sun. There's space, right, there's all

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<v Speaker 2>sorts of particles bouncing around, whizzing around, incredible density, very

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<v Speaker 2>high temperature, lots of matter loss of energy. All of

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<v Speaker 2>that sits within space. Right, the Sun is in space.

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<v Speaker 2>Even the heart of the Sun has space within it.

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<v Speaker 2>It's not empty space. It's very high energy, very dense space.

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<v Speaker 2>As you move away from the Sun, of course, that

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<v Speaker 2>space gets lower and lower energy, fewer particles. But everywhere

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<v Speaker 2>in the universe we think has space in it.

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<v Speaker 1>You mean everywhere in space has space in it.

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<v Speaker 2>Yeah. As soon as you use the word where, you're

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<v Speaker 2>assuming a location and location requires space. You can't really

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<v Speaker 2>have locations without space. Space represents the relationships between points, right,

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<v Speaker 2>That's really what space is.

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<v Speaker 1>I guess can you have the universe without space or

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<v Speaker 1>space without universe?

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<v Speaker 2>You might be able to have the universe without space

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<v Speaker 2>because we don't fundamentally know what space itself is. We

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<v Speaker 2>don't know if it's a necessary fundamental part of the universe,

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<v Speaker 2>meaning that like it has to exist, or if it's

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<v Speaker 2>an emergent property of something deeper, you know, something that

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<v Speaker 2>just sort of gets woven together out of the fundamental

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<v Speaker 2>bits of the universe that might not require space. If

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<v Speaker 2>you're not familiar with the concept of like fundamental versus emergent,

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<v Speaker 2>fundamental just means it's required, it's essential, whereas emergent means

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<v Speaker 2>it's not that. Sometimes it happens and sometimes it doesn't.

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<v Speaker 2>Like ice cream and pies we think are emergent properties

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<v Speaker 2>or something the universe can do, they can't exist. But

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<v Speaker 2>it's possible to have a universe without ice cream and pies.

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<v Speaker 2>So we think it might be possible to have a

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<v Speaker 2>universe without space, though that's not something we understand. There

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<v Speaker 2>are various theories out there, but that's an open question

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<v Speaker 2>in physically, so far we're operating under the assumption that

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<v Speaker 2>space is essential for the universe.

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<v Speaker 1>Well, I don't know about physics, but ice cream is

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<v Speaker 1>pretty essential to my life. I mean, a universe without

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<v Speaker 1>ice cream it's not a universe I want to live in.

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<v Speaker 2>And yet the vast majority of the history of the

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<v Speaker 2>universe had exactly zero ice cream in it, unless, of course,

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<v Speaker 2>there are ancient alien civilizations who also enjoyed cold custards.

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<v Speaker 1>We don't know. So you're saying you don't know if

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<v Speaker 1>aliens have ice cream or not. It's still an open question.

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<v Speaker 2>I can make no definitive statement about alien ice cream

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<v Speaker 2>that is exactly true.

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<v Speaker 1>Yes, Also, I think in a vacuum, no one can

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<v Speaker 1>hear you ice cream. You're like, I don't even know

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<v Speaker 1>where to go with that joke.

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<v Speaker 2>That was the perfect joke. There's no possible response to it.

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<v Speaker 2>A vacuum is there only possible response to that joke.

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<v Speaker 1>That's right, it's a micdrop moment.

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<v Speaker 2>Boom, Exactly, I just dropped my ice cream over here.

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<v Speaker 2>It's an ice cream drop moment.

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<v Speaker 1>But ana is back to our discussion. So you're saying

0:11:46.960 --> 0:11:50.880
<v Speaker 1>a vacuum is space with no matter in it, no

0:11:50.960 --> 0:11:51.760
<v Speaker 1>particles in it.

0:11:52.160 --> 0:11:57.079
<v Speaker 2>Yeah, that's exactly right. Whereas the minimum energy which includes particles. Right,

0:11:57.120 --> 0:11:59.760
<v Speaker 2>if you're talking about what space is, space is fundamentally

0:11:59.800 --> 0:12:02.880
<v Speaker 2>something we don't understand, but it has inside of it

0:12:02.920 --> 0:12:06.640
<v Speaker 2>the possibility to contain all sorts of energy and matter.

0:12:07.200 --> 0:12:10.319
<v Speaker 2>You can have protons in space. You can have photons

0:12:10.480 --> 0:12:13.280
<v Speaker 2>in space. Photons are not technically matter, they fall into

0:12:13.280 --> 0:12:16.440
<v Speaker 2>the radiation category. Right, So you can all sorts of

0:12:16.440 --> 0:12:20.360
<v Speaker 2>different kinds of energy inside of space, and we have

0:12:20.400 --> 0:12:24.280
<v Speaker 2>a huge variety of energy. Density in space. Right around

0:12:24.400 --> 0:12:27.720
<v Speaker 2>us on Earth is an incredible number of particles. You

0:12:27.760 --> 0:12:30.480
<v Speaker 2>take a cubic meter of air just in front of

0:12:30.520 --> 0:12:32.880
<v Speaker 2>you here on Earth, and there's like ten to the

0:12:33.000 --> 0:12:37.040
<v Speaker 2>twenty five mongules in that cubic meter of air. It's

0:12:37.080 --> 0:12:39.320
<v Speaker 2>like swarming with particles.

0:12:39.400 --> 0:12:42.280
<v Speaker 1>Well, I guess you know, for me traditional Newtonian kind

0:12:42.280 --> 0:12:44.920
<v Speaker 1>of high school physics, or you know, kind of as

0:12:44.920 --> 0:12:47.360
<v Speaker 1>we grow up kind of way. A particle are bits

0:12:47.360 --> 0:12:51.240
<v Speaker 1>of stuff that can fly around or float around, and

0:12:51.280 --> 0:12:53.880
<v Speaker 1>so it's kind of easy to imagine just a chunk

0:12:53.920 --> 0:12:57.320
<v Speaker 1>of space, a Cuba space, with no little bits in it. Right,

0:12:57.440 --> 0:12:59.640
<v Speaker 1>that would be a vacuum in a traditional sense.

0:13:00.040 --> 0:13:05.200
<v Speaker 2>In a traditional sense depending on whether you're including radiation also, right,

0:13:05.240 --> 0:13:07.360
<v Speaker 2>To really get a vacuum, you want to minimize the

0:13:07.400 --> 0:13:10.720
<v Speaker 2>overall energy, not just the total matter. So yeah, you

0:13:10.760 --> 0:13:13.360
<v Speaker 2>want to apply your vacuum and suck out all the bits.

0:13:13.520 --> 0:13:15.920
<v Speaker 2>But then you also want to prevent photons and other

0:13:16.000 --> 0:13:19.280
<v Speaker 2>kinds of non matter radiation from entering that cube of

0:13:19.320 --> 0:13:22.040
<v Speaker 2>space to get the best vacuum you can get.

0:13:22.280 --> 0:13:24.959
<v Speaker 1>Well, radiation is also particles, right, Like a photon is

0:13:25.000 --> 0:13:25.520
<v Speaker 1>a particle.

0:13:25.600 --> 0:13:27.920
<v Speaker 2>A photon is a particle, but it's not matter in

0:13:27.960 --> 0:13:31.640
<v Speaker 2>the same sense. These are like silly overlapping definitions. So yeah,

0:13:31.679 --> 0:13:34.800
<v Speaker 2>if you suck out all the particles, that would include photons.

0:13:35.040 --> 0:13:36.800
<v Speaker 2>So yes, that would be all the radiation.

0:13:37.000 --> 0:13:39.840
<v Speaker 1>But I guess it's complicated because now we know that

0:13:40.440 --> 0:13:43.000
<v Speaker 1>a particle is really just like a little blip in

0:13:43.040 --> 0:13:44.640
<v Speaker 1>a quantum field. Right.

0:13:45.040 --> 0:13:48.400
<v Speaker 2>So there are sort of two different philosophical pictures about

0:13:48.520 --> 0:13:51.200
<v Speaker 2>how this all works, and one that we talk about

0:13:51.200 --> 0:13:53.719
<v Speaker 2>on the podcast a lot is what you just described,

0:13:53.760 --> 0:13:57.280
<v Speaker 2>which is to meagine particles themselves as emergent properties. They're

0:13:57.280 --> 0:14:00.720
<v Speaker 2>not fundamental things in the universe. They're just eagles in

0:14:00.800 --> 0:14:03.960
<v Speaker 2>these fields that fill all of space. And in that picture,

0:14:04.080 --> 0:14:06.800
<v Speaker 2>fields are the most fundamental thing that when you have space,

0:14:07.080 --> 0:14:10.320
<v Speaker 2>it contains these fields. And these fields are like places

0:14:10.320 --> 0:14:13.080
<v Speaker 2>that energy can be. They're like, you know, how you

0:14:13.120 --> 0:14:16.040
<v Speaker 2>can stack energy up and if you wiggle them in

0:14:16.160 --> 0:14:18.440
<v Speaker 2>just the right way, then we call that a particle.

0:14:18.800 --> 0:14:22.960
<v Speaker 2>So that's sort of one picture of the structure of space, time,

0:14:23.080 --> 0:14:27.000
<v Speaker 2>and matter. There's another picture which says fields are nonsense.

0:14:27.200 --> 0:14:30.320
<v Speaker 2>Really everything is made of particles, and the way particles

0:14:30.320 --> 0:14:32.680
<v Speaker 2>communicate with each other and exchange momentum and stuff is

0:14:32.720 --> 0:14:36.080
<v Speaker 2>by exchanging other particles. So the sort of the fields picture,

0:14:36.200 --> 0:14:38.440
<v Speaker 2>which I think is more popular and maybe more intuitive,

0:14:38.560 --> 0:14:41.560
<v Speaker 2>But there is also this other picture that says that

0:14:41.640 --> 0:14:44.480
<v Speaker 2>particles are the most fundamental thing, and fields are nonsense

0:14:44.720 --> 0:14:48.920
<v Speaker 2>because remember, we never actually see fields themselves. Fields are

0:14:49.000 --> 0:14:53.000
<v Speaker 2>sort of a unobserved story. We tell ourselves to explain

0:14:53.080 --> 0:14:55.680
<v Speaker 2>what we do see in the universe, but we never

0:14:55.720 --> 0:14:58.800
<v Speaker 2>actually see them. We only see their effect on particles.

0:15:00.040 --> 0:15:03.200
<v Speaker 1>Fields are sort of like the potential for particles to happen.

0:15:03.400 --> 0:15:05.640
<v Speaker 2>Yeah, there's sort of like the parking lot into which

0:15:05.640 --> 0:15:08.880
<v Speaker 2>you can put cars, right, but again, we can't ever

0:15:08.960 --> 0:15:11.720
<v Speaker 2>see them directly, like even electric field which don't seem

0:15:11.720 --> 0:15:14.840
<v Speaker 2>controversial as a topic, like do electric fields exist? Well,

0:15:14.880 --> 0:15:16.640
<v Speaker 2>how do you see an electric field? You put an

0:15:16.680 --> 0:15:19.040
<v Speaker 2>electron in it and you see it move. What you're

0:15:19.080 --> 0:15:23.160
<v Speaker 2>really seeing is the electron moving, not the field itself,

0:15:23.560 --> 0:15:25.119
<v Speaker 2>So it's sort of a little bit indirect.

0:15:25.240 --> 0:15:27.400
<v Speaker 1>Well, maybe we're getting a little bit ahead of ourselves.

0:15:27.440 --> 0:15:29.480
<v Speaker 1>I think what you're saying is that the idea that

0:15:29.520 --> 0:15:32.520
<v Speaker 1>a vacuum is just a chunk of space without particles

0:15:32.520 --> 0:15:34.960
<v Speaker 1>in it's still or energy is still pretty good.

0:15:35.080 --> 0:15:38.040
<v Speaker 2>Yeah, that's a pretty good concept of what a vacuum is,

0:15:38.080 --> 0:15:41.680
<v Speaker 2>though it's surprisingly rare in the universe and hard to achieve.

0:15:41.880 --> 0:15:44.360
<v Speaker 1>Well, I guess maybe the first question or listeners might

0:15:44.400 --> 0:15:46.560
<v Speaker 1>have is is space out there really a vacuum.

0:15:46.640 --> 0:15:48.720
<v Speaker 2>It's hard for me to say that anywhere in the

0:15:48.840 --> 0:15:52.320
<v Speaker 2>universe is actually a true vacuum. If you go like

0:15:52.640 --> 0:15:56.200
<v Speaker 2>near the surface of the Earth where space officially starts,

0:15:56.360 --> 0:15:59.480
<v Speaker 2>which is like one hundred kilometers above the surface of

0:15:59.520 --> 0:16:02.280
<v Speaker 2>the Earth, although the United States calls you an astronaut,

0:16:02.320 --> 0:16:05.120
<v Speaker 2>if you've been above eighty kilometers, then that's where space

0:16:05.160 --> 0:16:07.760
<v Speaker 2>officially starts. But there's a lot of stuff out there still.

0:16:07.760 --> 0:16:10.200
<v Speaker 2>You know, the Earth's atmosphere doesn't end. It's not like

0:16:10.240 --> 0:16:12.840
<v Speaker 2>there's a pane of glass there that's holding the atmosphere

0:16:12.880 --> 0:16:15.440
<v Speaker 2>and it should drifts off gradually. So there's still a

0:16:15.480 --> 0:16:17.920
<v Speaker 2>lot of atmosphere up there. And if you fly your

0:16:17.920 --> 0:16:20.920
<v Speaker 2>satellite at that orbit, you'll be dragged by that atmosphere

0:16:20.920 --> 0:16:24.480
<v Speaker 2>and eventually you deorbit back to the Earth's surface. So

0:16:24.520 --> 0:16:26.560
<v Speaker 2>we know that there's definitely a lot of stuff out

0:16:26.560 --> 0:16:27.440
<v Speaker 2>there still.

0:16:28.000 --> 0:16:30.080
<v Speaker 1>Just about the Earth or just outside of the Earth.

0:16:30.160 --> 0:16:32.040
<v Speaker 1>It's kind of you say, it's kind of hard to

0:16:32.520 --> 0:16:34.080
<v Speaker 1>find a true vacuum.

0:16:33.640 --> 0:16:35.440
<v Speaker 2>And so you go further, right like, Okay, I'm gonna

0:16:35.520 --> 0:16:39.320
<v Speaker 2>leave Earth entirely, I'm gonna go into interplanetary space. Halfway

0:16:39.360 --> 0:16:42.160
<v Speaker 2>between Earth and Mars. Well, then there's still a lot

0:16:42.200 --> 0:16:44.360
<v Speaker 2>of stuff out there. You know, the Sun pumps out

0:16:44.440 --> 0:16:48.160
<v Speaker 2>not just photons which we consider energy and particles and

0:16:48.200 --> 0:16:53.160
<v Speaker 2>so it disrupts your vacuum, but also matter particles, electrons, protons,

0:16:53.280 --> 0:16:56.160
<v Speaker 2>alpha particles, very very high speed particles moving on like

0:16:56.240 --> 0:16:58.920
<v Speaker 2>hundreds of kilometers per second. And there's not a tiny

0:16:59.040 --> 0:17:02.160
<v Speaker 2>number of them. There's like millions of protons per cubic

0:17:02.240 --> 0:17:04.600
<v Speaker 2>meter out there in interplanetary space.

0:17:04.960 --> 0:17:06.840
<v Speaker 1>Whoa coming from the Sun, right.

0:17:06.720 --> 0:17:08.800
<v Speaker 2>Yeah, this is the solar wind. And you know that's

0:17:08.840 --> 0:17:11.280
<v Speaker 2>a tiny number compared to the density of air here

0:17:11.320 --> 0:17:15.760
<v Speaker 2>on Earth. It's like ten to the nineteen times less dense.

0:17:15.800 --> 0:17:17.879
<v Speaker 2>So it feels like a vacuum if somebody chucks you

0:17:17.920 --> 0:17:19.840
<v Speaker 2>out the air lock, But it's not even really close

0:17:19.880 --> 0:17:21.879
<v Speaker 2>to a vacuum because you still have millions of particles

0:17:21.920 --> 0:17:22.640
<v Speaker 2>per cubic meter.

0:17:22.920 --> 0:17:25.320
<v Speaker 1>Well, what if you go out further into space. Can

0:17:25.359 --> 0:17:26.840
<v Speaker 1>you find a true vacuum out there?

0:17:26.920 --> 0:17:29.359
<v Speaker 2>If you like leave the Solar System and go into

0:17:29.440 --> 0:17:33.840
<v Speaker 2>interstellar space, still inside the galaxy, then you're still surrounded

0:17:33.840 --> 0:17:37.040
<v Speaker 2>by what we call the interstellar medium, which is mostly

0:17:37.160 --> 0:17:39.560
<v Speaker 2>gas and a little bit of dust some cosmic rays,

0:17:39.560 --> 0:17:42.680
<v Speaker 2>and here it's much more sparse and it's highly variable.

0:17:42.760 --> 0:17:44.800
<v Speaker 2>You can get from like ten to the minus four

0:17:45.040 --> 0:17:47.840
<v Speaker 2>up to ten to the six molecules per cubic meter,

0:17:48.359 --> 0:17:51.080
<v Speaker 2>so it's still really not close to empty. And don't

0:17:51.080 --> 0:17:54.320
<v Speaker 2>forget that's just the kind of matter we know about, right,

0:17:54.520 --> 0:17:57.920
<v Speaker 2>protons and electrons. There's still also the dark matter, which

0:17:57.960 --> 0:18:00.760
<v Speaker 2>is filling the galaxy. Inside the galley, we're inside the

0:18:00.840 --> 0:18:04.480
<v Speaker 2>dark matter halo, which is five times as much matter

0:18:04.560 --> 0:18:07.520
<v Speaker 2>as the normal matter. So inside the galaxy you can't

0:18:07.560 --> 0:18:09.120
<v Speaker 2>really ever say you have a vacuum.

0:18:09.240 --> 0:18:11.560
<v Speaker 1>What about like the far reaches of space, Like if

0:18:11.560 --> 0:18:14.240
<v Speaker 1>you go deep out there in the middle of nowhere,

0:18:14.280 --> 0:18:17.040
<v Speaker 1>really in the middle of nowhere between galaxies.

0:18:17.280 --> 0:18:20.040
<v Speaker 2>So take a point, for example, between the Milky Way

0:18:20.080 --> 0:18:24.119
<v Speaker 2>and Andromeda. You're far outside of the galaxy. There's still

0:18:24.200 --> 0:18:28.800
<v Speaker 2>something there. There's the intergalactic medium. This is a rarefied plasma.

0:18:28.840 --> 0:18:32.480
<v Speaker 2>It's mostly protons and it's not zero. There's like one

0:18:32.520 --> 0:18:35.920
<v Speaker 2>to ten atoms per cubic meter, and there's actually kind

0:18:35.920 --> 0:18:39.000
<v Speaker 2>of a lot of stuff out there, this plasma that's

0:18:39.040 --> 0:18:42.880
<v Speaker 2>between galaxies. This number sort of shocks me. Is about

0:18:42.920 --> 0:18:45.879
<v Speaker 2>half of the ordinary matter in the universe. Like you

0:18:45.880 --> 0:18:47.680
<v Speaker 2>look up at the night sky and you see stars,

0:18:47.720 --> 0:18:50.080
<v Speaker 2>and you think about galaxies, and you know, there's a

0:18:50.080 --> 0:18:51.960
<v Speaker 2>lot of dark matter out there that we can't see,

0:18:52.000 --> 0:18:54.760
<v Speaker 2>but you imagine probably we're seeing all the normal matter.

0:18:55.200 --> 0:18:58.440
<v Speaker 2>But something like half fifty percent of all the normal

0:18:58.480 --> 0:19:01.560
<v Speaker 2>matter in the universe is between galaxies, any sort of

0:19:01.640 --> 0:19:04.439
<v Speaker 2>filaments of plasma that connects them together.

0:19:05.080 --> 0:19:08.040
<v Speaker 1>Yeah, because these filaments are huge, right, Like the space

0:19:08.080 --> 0:19:11.919
<v Speaker 1>between galaxies and clusters of galaxies. It's a lot. So

0:19:12.000 --> 0:19:14.080
<v Speaker 1>even if you only have one to ten atoms per

0:19:14.119 --> 0:19:17.320
<v Speaker 1>cubic meter, it adds up to as you're saying, half

0:19:17.359 --> 0:19:18.400
<v Speaker 1>of the stuff in the universe.

0:19:18.960 --> 0:19:21.200
<v Speaker 2>Yeah, it's really a lot of stuff. But you can

0:19:21.200 --> 0:19:23.520
<v Speaker 2>get more sparse. Right, You're like, let's not hang out

0:19:23.520 --> 0:19:26.680
<v Speaker 2>between the galaxies. Let's leave the galactic cluster, or let's

0:19:26.680 --> 0:19:30.280
<v Speaker 2>find one of these supervoids that are between the superclusters.

0:19:30.400 --> 0:19:32.720
<v Speaker 2>Right and out there is the closest you can get

0:19:32.760 --> 0:19:35.720
<v Speaker 2>to a vacuum. You know, the number density of particles,

0:19:35.760 --> 0:19:39.320
<v Speaker 2>the particles per cubic meter drops to almost zero. There's

0:19:39.359 --> 0:19:42.840
<v Speaker 2>almost no photons out there either. It's like as close

0:19:42.920 --> 0:19:44.240
<v Speaker 2>to zero as you can.

0:19:44.160 --> 0:19:46.399
<v Speaker 1>Get wait, isn't that weird? Like how can you have

0:19:46.440 --> 0:19:48.880
<v Speaker 1>no photons? Like you'd be there and you would look

0:19:48.880 --> 0:19:51.200
<v Speaker 1>out around you and you wouldn't see anything.

0:19:51.440 --> 0:19:54.800
<v Speaker 2>It'll never actually get to zero. Right, You'll be as

0:19:54.920 --> 0:19:57.800
<v Speaker 2>distant as possible from all of those galaxies, and so

0:19:57.840 --> 0:20:00.480
<v Speaker 2>you'll have the dimmest view of all of them. But

0:20:00.520 --> 0:20:03.320
<v Speaker 2>you're right, it'll never actually get to zero. Right. It's

0:20:03.320 --> 0:20:06.280
<v Speaker 2>not like you look around you and you see total blackness.

0:20:06.880 --> 0:20:09.520
<v Speaker 2>So the number of photons will never actually get to zero,

0:20:09.640 --> 0:20:12.760
<v Speaker 2>even inside those supervoids. It's like the furthest you can

0:20:12.800 --> 0:20:14.800
<v Speaker 2>get from all the light sources. It's like if you're

0:20:14.800 --> 0:20:16.800
<v Speaker 2>trying to find a dark spot in your city to

0:20:16.880 --> 0:20:19.120
<v Speaker 2>look at the night sky, and you get as far

0:20:19.160 --> 0:20:21.800
<v Speaker 2>away as possible from all the street lights, you're still

0:20:21.880 --> 0:20:23.440
<v Speaker 2>going to have some light there.

0:20:23.760 --> 0:20:26.640
<v Speaker 1>Are you trying to say that there is no perfect

0:20:26.760 --> 0:20:30.640
<v Speaker 1>vacuum in the universe, naturally occurring perfect vacuum in the universe.

0:20:31.080 --> 0:20:33.360
<v Speaker 1>It's not possible to find a perfect vacuum.

0:20:33.400 --> 0:20:35.800
<v Speaker 2>It's probably impossible for all of those reasons. I think

0:20:35.840 --> 0:20:39.040
<v Speaker 2>every chunk of space probably has at least one photon

0:20:39.119 --> 0:20:42.360
<v Speaker 2>in it from some distant galaxy that threw that particle

0:20:42.440 --> 0:20:43.240
<v Speaker 2>in that direction.

0:20:44.040 --> 0:20:46.520
<v Speaker 1>But that's kind of an average though, right, Like, maybe

0:20:46.640 --> 0:20:49.080
<v Speaker 1>when you're out there, you see a photon every once

0:20:49.119 --> 0:20:51.119
<v Speaker 1>in a while, but in between the times that you

0:20:51.119 --> 0:20:53.320
<v Speaker 1>see a photon, you would be sort of in a

0:20:53.320 --> 0:20:54.560
<v Speaker 1>perfect vacuum potentially.

0:20:54.640 --> 0:20:56.959
<v Speaker 2>And here's where we run up against the technical question,

0:20:57.359 --> 0:21:02.000
<v Speaker 2>because every chunk of space also contains dark energy, right.

0:21:02.080 --> 0:21:04.600
<v Speaker 2>Dark energy not something we understand, but every chunk of

0:21:04.640 --> 0:21:07.560
<v Speaker 2>space has some of it. So the technical definition of

0:21:07.560 --> 0:21:10.120
<v Speaker 2>a vacuum is not space with no energy in it.

0:21:10.119 --> 0:21:13.960
<v Speaker 2>It's space with a minimum amount of energy. So you

0:21:14.040 --> 0:21:16.240
<v Speaker 2>can be in a chunk of space that has some

0:21:16.560 --> 0:21:18.600
<v Speaker 2>energy in it and still call that a vacuum if

0:21:18.640 --> 0:21:22.560
<v Speaker 2>you're convinced that that's the most relaxed possible state of space.

0:21:23.119 --> 0:21:25.479
<v Speaker 1>Hmm. It sounds like maybe there's a concept of a

0:21:25.480 --> 0:21:28.000
<v Speaker 1>perfect vacuum, and then there's a concept of like what's

0:21:28.040 --> 0:21:32.560
<v Speaker 1>the minimum vacuum that the universe naturally has out there?

0:21:32.640 --> 0:21:35.359
<v Speaker 1>You know, kind of like temperature, right, Like there's absolute zero,

0:21:35.720 --> 0:21:38.280
<v Speaker 1>and then there's what actually actually seen the universe.

0:21:38.320 --> 0:21:41.760
<v Speaker 2>There's what space theoretically could accomplish in terms of relaxation,

0:21:42.280 --> 0:21:45.040
<v Speaker 2>and then there's this sort of most relaxed space that

0:21:45.160 --> 0:21:48.040
<v Speaker 2>actually exists in the universe, and those could be different.

0:21:48.440 --> 0:21:52.440
<v Speaker 1>Hmm. All right, so let's get into what would actually

0:21:52.480 --> 0:21:55.200
<v Speaker 1>happen if you create a perfect vacuum in the universe.

0:21:55.320 --> 0:21:57.840
<v Speaker 1>What would that mean? Is it possible and would it

0:21:57.880 --> 0:22:00.360
<v Speaker 1>be as tidy as we want it to be? Dig

0:22:00.400 --> 0:22:15.280
<v Speaker 1>into that, But first let's take a quick break. All right,

0:22:15.320 --> 0:22:17.920
<v Speaker 1>we're talking about vacuuming the universe. It sounds like the

0:22:18.200 --> 0:22:20.480
<v Speaker 1>universe has a lot of space that you need to

0:22:20.960 --> 0:22:21.440
<v Speaker 1>suck up.

0:22:22.320 --> 0:22:25.480
<v Speaker 2>It's a big chore to clean up the whole universe.

0:22:25.680 --> 0:22:27.800
<v Speaker 1>Now, is the universe more of like a shag carpet

0:22:28.160 --> 0:22:30.920
<v Speaker 1>or you think it's more of a wooden floors kind

0:22:30.960 --> 0:22:31.480
<v Speaker 1>of situation.

0:22:31.760 --> 0:22:35.360
<v Speaker 2>I think it'd be pretty hard to totally thoroughly cleanse

0:22:35.440 --> 0:22:38.080
<v Speaker 2>the universe, So yeah, it's definitely shag carpeting out there.

0:22:38.280 --> 0:22:40.800
<v Speaker 1>Or maybe right like, we don't know if maybe the

0:22:40.880 --> 0:22:43.960
<v Speaker 1>universe encompasses all of the matter in the universe, or

0:22:44.000 --> 0:22:45.840
<v Speaker 1>maybe there's a bunch of universe out there that is

0:22:45.880 --> 0:22:46.520
<v Speaker 1>truly empty.

0:22:46.760 --> 0:22:50.439
<v Speaker 2>It's possible, though cosmologists prefer the assumption that the universe

0:22:50.520 --> 0:22:53.479
<v Speaker 2>is essentially the same everywhere. It's not a totally solid

0:22:53.520 --> 0:22:56.240
<v Speaker 2>experimental point, but it's sort of the simplest idea that

0:22:56.280 --> 0:22:58.520
<v Speaker 2>there's no special place in the universe. And so when

0:22:58.560 --> 0:23:02.560
<v Speaker 2>you zoom out really far and cosmic scales, we see

0:23:02.600 --> 0:23:05.040
<v Speaker 2>so far the universe has the same density of stuff

0:23:05.080 --> 0:23:08.760
<v Speaker 2>basically everywhere, again massively zooming out right on the scale

0:23:08.760 --> 0:23:11.640
<v Speaker 2>of superclusters of galaxies. So that would suggest that there

0:23:11.680 --> 0:23:15.440
<v Speaker 2>isn't any place in space that's like really truly specially empty,

0:23:15.480 --> 0:23:17.920
<v Speaker 2>different from the part of the universe that we find

0:23:17.960 --> 0:23:20.320
<v Speaker 2>ourselves in. So that's just an assumption, right, which is

0:23:20.359 --> 0:23:23.399
<v Speaker 2>extrapolating from what we see out to infinity, which is

0:23:23.440 --> 0:23:24.280
<v Speaker 2>always dangerous.

0:23:24.760 --> 0:23:28.800
<v Speaker 1>Yeah. I think sometimes people talk about the analogy with

0:23:28.960 --> 0:23:30.879
<v Speaker 1>like fish in the water, right, Like you could be

0:23:30.920 --> 0:23:32.959
<v Speaker 1>a fish at the bottom of the ocean and think, oh,

0:23:33.320 --> 0:23:35.560
<v Speaker 1>the whole universe is filled with water, right, because as

0:23:35.600 --> 0:23:36.880
<v Speaker 1>far as I can see, there's water.

0:23:38.840 --> 0:23:41.120
<v Speaker 2>Yeah, that's right. I think that's Max tech Mark's analogy,

0:23:41.160 --> 0:23:43.480
<v Speaker 2>which is really wonderful because it gives you a sense

0:23:43.560 --> 0:23:46.520
<v Speaker 2>of your naivete and how you might not know what

0:23:46.600 --> 0:23:49.320
<v Speaker 2>you don't know. And there could of course be boundaries

0:23:49.640 --> 0:23:52.080
<v Speaker 2>to the kind of universe that you imagine we could

0:23:52.080 --> 0:23:54.800
<v Speaker 2>be living in a bubble where these laws of physics

0:23:54.800 --> 0:23:57.720
<v Speaker 2>apply and everything seems to make sense to us, but

0:23:57.760 --> 0:23:59.680
<v Speaker 2>there could be an edge to it out past, which

0:23:59.800 --> 0:24:03.440
<v Speaker 2>the universe is in another phase, you know, crazy densities

0:24:03.480 --> 0:24:07.199
<v Speaker 2>where quantum gravity applies, or maybe the inflaton field hasn't

0:24:07.200 --> 0:24:10.960
<v Speaker 2>decayed yet, or some other crazy nosis, so it's always possible.

0:24:11.240 --> 0:24:13.919
<v Speaker 1>Or maybe we're living inside of a vacuum of someone

0:24:13.960 --> 0:24:17.280
<v Speaker 1>cleaning up their universe in a super mega universe.

0:24:17.400 --> 0:24:19.480
<v Speaker 2>Man, that would totally suck so well.

0:24:19.520 --> 0:24:21.840
<v Speaker 1>As you were saying earlier, it's kind of hard to

0:24:21.880 --> 0:24:25.040
<v Speaker 1>find a naturally occurring perfect vacuum because even if you're

0:24:25.080 --> 0:24:29.400
<v Speaker 1>out there in the depth of space in between galactic clusters,

0:24:29.440 --> 0:24:31.320
<v Speaker 1>there's stills kind of stuff in it. There might be

0:24:31.359 --> 0:24:33.840
<v Speaker 1>some a little bit of light or an atom here

0:24:33.920 --> 0:24:37.160
<v Speaker 1>or there, or maybe even dark energy or dark matter.

0:24:37.400 --> 0:24:39.960
<v Speaker 2>Right, Yeah, that's right. It's hard to find a chunk

0:24:40.000 --> 0:24:44.080
<v Speaker 2>of space that really has no particles in it because

0:24:44.119 --> 0:24:47.680
<v Speaker 2>the universe is buzzing with stuff and that's flying everywhere

0:24:47.760 --> 0:24:48.960
<v Speaker 2>and filling everything up.

0:24:49.359 --> 0:24:51.680
<v Speaker 1>So then I guess the next question that we can

0:24:51.720 --> 0:24:57.040
<v Speaker 1>ask is is the perfect vacuum possible? And what would

0:24:57.040 --> 0:24:59.399
<v Speaker 1>it look like, like, can you have a chunk of

0:24:59.440 --> 0:25:03.000
<v Speaker 1>space with that any particle, matter or energy in it?

0:25:03.200 --> 0:25:04.520
<v Speaker 1>What's left if you have none of that?

0:25:04.880 --> 0:25:07.960
<v Speaker 2>Yeah, So imagine that you were able to somehow rid

0:25:08.000 --> 0:25:10.040
<v Speaker 2>a chunk of space of all the particles. Maybe you

0:25:10.080 --> 0:25:13.639
<v Speaker 2>built a box that blocked all photons another matter from entering,

0:25:13.680 --> 0:25:16.040
<v Speaker 2>and you sucked everything out of it. What would be

0:25:16.200 --> 0:25:18.959
<v Speaker 2>in there? Right? What is sort of the nature of nothing?

0:25:19.040 --> 0:25:22.120
<v Speaker 2>What is the minimum thing that exists in the universe?

0:25:22.240 --> 0:25:24.880
<v Speaker 2>Or like, what is reality when there's nothing in it?

0:25:25.600 --> 0:25:27.399
<v Speaker 2>And you know, we don't know the answer to that

0:25:27.480 --> 0:25:29.919
<v Speaker 2>question at the deepest level, but we do have a

0:25:29.960 --> 0:25:32.840
<v Speaker 2>theory that describes it. Right. We call that thing space,

0:25:32.920 --> 0:25:36.320
<v Speaker 2>and space still has a structure to it even if

0:25:36.359 --> 0:25:38.879
<v Speaker 2>you suck all the stuff out of it. Right, This

0:25:38.920 --> 0:25:40.720
<v Speaker 2>is what we were talking about earlier, that there's a

0:25:40.880 --> 0:25:45.600
<v Speaker 2>possibility for things to exist, and that possibility are the fields.

0:25:45.960 --> 0:25:49.080
<v Speaker 2>We think of these as part of space itself, That

0:25:49.160 --> 0:25:52.480
<v Speaker 2>these fields exist even when there's nothing in them, that

0:25:52.520 --> 0:25:55.320
<v Speaker 2>the possibility for things to exist is part of the

0:25:55.320 --> 0:25:56.960
<v Speaker 2>structure of space itself.

0:25:57.320 --> 0:25:57.560
<v Speaker 4>Hmm.

0:25:57.920 --> 0:25:59.680
<v Speaker 1>I guess, as you were saying, it kind of depends

0:25:59.720 --> 0:26:02.160
<v Speaker 1>on what that you consider fields to be a thing

0:26:02.440 --> 0:26:04.800
<v Speaker 1>or not. Like, if you consider them to be a thing,

0:26:05.040 --> 0:26:07.199
<v Speaker 1>then fields kind of take up all of space in

0:26:07.240 --> 0:26:10.160
<v Speaker 1>the universe, right, So you can't have a space without fields.

0:26:10.200 --> 0:26:13.520
<v Speaker 1>But if fields are just kind of a made up concept,

0:26:13.560 --> 0:26:15.200
<v Speaker 1>then it is possible to have empty space.

0:26:15.440 --> 0:26:17.600
<v Speaker 2>If you consider field to be the most fundamental, then yes,

0:26:17.680 --> 0:26:20.800
<v Speaker 2>they are the bedrock. They are contained as part of space.

0:26:20.840 --> 0:26:23.280
<v Speaker 2>They're a fundamental aspect of the universe. And we can

0:26:23.320 --> 0:26:25.520
<v Speaker 2>talk in a minute about like what is the lowest

0:26:25.640 --> 0:26:28.840
<v Speaker 2>energy those fields can occupy, what would that vacuum mean, etcetera,

0:26:28.880 --> 0:26:31.280
<v Speaker 2>et cetera. If you reject fields and say, look, I

0:26:31.280 --> 0:26:33.880
<v Speaker 2>can't ever see fields. I don't think that those really

0:26:33.920 --> 0:26:36.000
<v Speaker 2>are the way particles push on each other, then you

0:26:36.040 --> 0:26:39.840
<v Speaker 2>have another picture, which is virtual particles. Particles push on

0:26:39.840 --> 0:26:42.399
<v Speaker 2>each other by exchanging these virtual particles, you know, and

0:26:42.480 --> 0:26:45.720
<v Speaker 2>two electrons whiz by each other. They're not using their

0:26:45.720 --> 0:26:48.800
<v Speaker 2>fields to push on each other. They're exchanging virtual photons.

0:26:49.000 --> 0:26:51.040
<v Speaker 2>So if you use that picture, you don't just delete

0:26:51.040 --> 0:26:53.440
<v Speaker 2>the field to replace it with nothing else. You delete

0:26:53.480 --> 0:26:55.600
<v Speaker 2>the fields and you replace it with an infinite number

0:26:55.680 --> 0:26:59.160
<v Speaker 2>of virtual particles. So in neither picture of the universe

0:26:59.200 --> 0:27:02.080
<v Speaker 2>is really true empty, even when you have no real

0:27:02.359 --> 0:27:03.040
<v Speaker 2>matter in it.

0:27:03.960 --> 0:27:07.600
<v Speaker 1>Well, is it possible to have space without fields? Right?

0:27:07.640 --> 0:27:10.720
<v Speaker 1>Because fields kind of have come and gone in our

0:27:10.800 --> 0:27:14.080
<v Speaker 1>history of the universe, and also I think mathematically it's

0:27:14.119 --> 0:27:16.199
<v Speaker 1>sort of possible to just not have a field and

0:27:16.240 --> 0:27:17.200
<v Speaker 1>still have space. Right.

0:27:17.400 --> 0:27:19.119
<v Speaker 2>What do you mean fields have come and gone? You

0:27:19.160 --> 0:27:22.040
<v Speaker 2>mean it's a scientific concept, or in the cosmological history

0:27:22.040 --> 0:27:22.640
<v Speaker 2>of the universe.

0:27:22.800 --> 0:27:25.000
<v Speaker 1>I mean, like in the cosmological history right, like you know,

0:27:25.040 --> 0:27:26.879
<v Speaker 1>the Big Bang, we didn't have some of the fields

0:27:26.880 --> 0:27:27.480
<v Speaker 1>we have. Right.

0:27:27.520 --> 0:27:29.879
<v Speaker 2>Our description of the history of the universe goes back really,

0:27:29.920 --> 0:27:32.200
<v Speaker 2>really far to what we think is like a few

0:27:32.359 --> 0:27:35.840
<v Speaker 2>tiny moments in time after maybe the universe was created.

0:27:35.920 --> 0:27:37.560
<v Speaker 2>But it really goes back only as far as we

0:27:37.600 --> 0:27:40.400
<v Speaker 2>can describe with our current laws of physics, and those

0:27:40.480 --> 0:27:43.520
<v Speaker 2>laws always include fields. So it might be that before

0:27:43.520 --> 0:27:45.960
<v Speaker 2>a certain point there weren't fields, But that's because the

0:27:46.040 --> 0:27:48.360
<v Speaker 2>universe is like in a different phase where fields are

0:27:48.359 --> 0:27:51.679
<v Speaker 2>no longer a good description of what's happening, and so

0:27:51.720 --> 0:27:54.160
<v Speaker 2>we use fields as a way to describe the universe

0:27:54.200 --> 0:27:57.360
<v Speaker 2>we're in right now, we don't know if fields are

0:27:57.400 --> 0:28:00.960
<v Speaker 2>fundamental or when the universe changes conditions to a point

0:28:00.960 --> 0:28:03.240
<v Speaker 2>where these laws of physics are no longer relevant that

0:28:03.320 --> 0:28:07.240
<v Speaker 2>some other description is useful. Going back to your fish analogy,

0:28:07.359 --> 0:28:10.199
<v Speaker 2>sort of imagining that the universe currently is in a

0:28:10.240 --> 0:28:13.600
<v Speaker 2>certain phase, like the way the fish are swimming through water,

0:28:13.640 --> 0:28:15.719
<v Speaker 2>and that water is a certain phase, and they develop

0:28:15.840 --> 0:28:18.919
<v Speaker 2>laws of physics that describe, you know, the fluid dynamics

0:28:18.920 --> 0:28:21.440
<v Speaker 2>of that water. If the water was to boil, then

0:28:21.480 --> 0:28:23.520
<v Speaker 2>the water's in a new phase and their laws don't

0:28:23.520 --> 0:28:26.439
<v Speaker 2>work anymore. In the same way, there's a moment before

0:28:26.560 --> 0:28:30.560
<v Speaker 2>which we don't think fields probably describe the phase of

0:28:30.640 --> 0:28:33.280
<v Speaker 2>the universe. We don't know how to describe it requires

0:28:33.359 --> 0:28:36.840
<v Speaker 2>quantum gravity. But from that moment and forward, we think

0:28:36.920 --> 0:28:40.080
<v Speaker 2>fields are a good description of the whole universe. So

0:28:40.240 --> 0:28:43.040
<v Speaker 2>in that sense, yeah, fields haven't always existed, but only

0:28:43.080 --> 0:28:46.080
<v Speaker 2>because this phase of the universe hasn't always existed.

0:28:47.160 --> 0:28:48.640
<v Speaker 1>Well, I guess what I mean is like, if it

0:28:48.720 --> 0:28:52.240
<v Speaker 1>is a phase, it kind of seems optional, kind of

0:28:52.240 --> 0:28:54.840
<v Speaker 1>like the water in the ocean, right, Like, you know,

0:28:54.880 --> 0:28:58.440
<v Speaker 1>you can imagine a universe existing without the muon field

0:28:58.640 --> 0:29:01.600
<v Speaker 1>for example, it's out field or the you know, certain

0:29:01.680 --> 0:29:04.200
<v Speaker 1>quarks or whatever, and you would still maybe have a

0:29:04.200 --> 0:29:07.240
<v Speaker 1>functioning universe, which means maybe they're optional, in which case

0:29:07.280 --> 0:29:09.320
<v Speaker 1>maybe you can have a universe without fields.

0:29:09.400 --> 0:29:11.520
<v Speaker 2>We don't know the answer to that question, right, What

0:29:11.680 --> 0:29:15.040
<v Speaker 2>is the physics of other phases of the universe where

0:29:15.080 --> 0:29:17.560
<v Speaker 2>our laws of physics do not apply. That's a question

0:29:17.640 --> 0:29:20.640
<v Speaker 2>of like what is quantum gravity? You know what happens

0:29:20.680 --> 0:29:23.680
<v Speaker 2>when things get super duper dense and very very hot,

0:29:23.960 --> 0:29:26.920
<v Speaker 2>where gravity is important and quantum mechanics is important. We

0:29:27.040 --> 0:29:29.520
<v Speaker 2>just don't have a theory that describes that. Some candidate

0:29:29.560 --> 0:29:32.560
<v Speaker 2>theories do include fields, right, There's still are fields in

0:29:32.640 --> 0:29:34.920
<v Speaker 2>some of those theories, and so it might be that

0:29:34.920 --> 0:29:37.480
<v Speaker 2>there are still fields back before that moment in time

0:29:37.520 --> 0:29:40.600
<v Speaker 2>when our current theories break down. We just don't know.

0:29:41.160 --> 0:29:43.360
<v Speaker 2>So from that point of view, you don't always have fields.

0:29:43.440 --> 0:29:45.560
<v Speaker 2>But if we're talking about, like what is a vacuum,

0:29:46.000 --> 0:29:48.000
<v Speaker 2>I think that's sort of in the context of our

0:29:48.120 --> 0:29:51.560
<v Speaker 2>current kind of space, the current phase of the universe

0:29:51.600 --> 0:29:53.840
<v Speaker 2>that we're in. You can still say what is a

0:29:53.920 --> 0:29:55.920
<v Speaker 2>vacuum in that context.

0:29:55.880 --> 0:29:57.800
<v Speaker 1>So then I'm trying to figure out what you're trying

0:29:57.800 --> 0:30:00.400
<v Speaker 1>to say. Are you saying that you can not have

0:30:00.480 --> 0:30:03.040
<v Speaker 1>a vacuum a true vacuum. Or are you saying that

0:30:03.280 --> 0:30:05.680
<v Speaker 1>you can't have a vacuum where there's not even fields

0:30:05.720 --> 0:30:08.360
<v Speaker 1>in it, or does your definition of a vacuum just

0:30:08.400 --> 0:30:12.200
<v Speaker 1>includes the fields as a base kind of layer of existence.

0:30:12.360 --> 0:30:14.880
<v Speaker 2>It's that last one. What we consider a vacuum is

0:30:15.040 --> 0:30:18.480
<v Speaker 2>space at its most relaxed, which is what is the

0:30:18.640 --> 0:30:22.840
<v Speaker 2>least energy possible to exist in space. And because our

0:30:22.920 --> 0:30:25.880
<v Speaker 2>concept of space includes these built in fields, they will

0:30:25.880 --> 0:30:30.200
<v Speaker 2>always contain fields. So a vacuum is not perfect zeroness,

0:30:30.560 --> 0:30:33.560
<v Speaker 2>complete emptiness. It's a most relaxed state of space which

0:30:33.600 --> 0:30:35.440
<v Speaker 2>will always include these fields.

0:30:36.080 --> 0:30:39.440
<v Speaker 1>M But I guess, is it theoretically possible to have

0:30:39.600 --> 0:30:41.440
<v Speaker 1>zero energy space?

0:30:41.840 --> 0:30:44.840
<v Speaker 2>It is not theoretically possible because all these fields are

0:30:45.000 --> 0:30:49.200
<v Speaker 2>quantum fields. They're not classical fields like Maxwell's theory of electromagnetism,

0:30:49.200 --> 0:30:52.680
<v Speaker 2>which has like electric and magnetic fields oscillating which makes light.

0:30:52.800 --> 0:30:55.280
<v Speaker 2>Those fields could be absolute zero. You could have them

0:30:55.280 --> 0:30:57.720
<v Speaker 2>at zero energy. You could have zero electric field and

0:30:57.800 --> 0:31:00.920
<v Speaker 2>zero magnetic field. Our modern view is that these fields

0:31:00.920 --> 0:31:04.520
<v Speaker 2>are quantum fields, which means they oscillate differently instead of

0:31:04.560 --> 0:31:07.120
<v Speaker 2>whiggling like a string, where they can take any value.

0:31:07.400 --> 0:31:10.680
<v Speaker 2>There are only certain solutions that are allowed, they're like discretized,

0:31:10.720 --> 0:31:14.640
<v Speaker 2>they're quantized, and the mathematics don't work for zero energy,

0:31:15.040 --> 0:31:18.560
<v Speaker 2>Like the solution of the quantum field equations don't allow

0:31:18.600 --> 0:31:22.120
<v Speaker 2>a zero energy solutions. It's like a minimum energy required

0:31:22.480 --> 0:31:25.480
<v Speaker 2>for any quantum fields. They have to be like bubbling

0:31:25.520 --> 0:31:30.120
<v Speaker 2>and frothing at some tiny little level, at the very minimum.

0:31:30.120 --> 0:31:31.920
<v Speaker 1>I guess maybe what I'm asking it at a fundamental

0:31:32.000 --> 0:31:34.680
<v Speaker 1>level is can you have a universe with no fields?

0:31:34.840 --> 0:31:36.960
<v Speaker 2>Are you asking whether we could have a universe with

0:31:37.120 --> 0:31:40.200
<v Speaker 2>fields that are at zero or a universe where space

0:31:40.520 --> 0:31:43.240
<v Speaker 2>literally does not have the capacity for fields.

0:31:43.440 --> 0:31:45.840
<v Speaker 1>Can you have a universe where there are no fields

0:31:45.880 --> 0:31:46.160
<v Speaker 1>in it?

0:31:46.480 --> 0:31:49.200
<v Speaker 2>That? We don't know? Right? Our current definition of space

0:31:49.560 --> 0:31:52.640
<v Speaker 2>has these fields built in. Is it possible to have

0:31:52.680 --> 0:31:55.440
<v Speaker 2>another kind of space without fields, where you wouldn't even

0:31:55.520 --> 0:31:58.080
<v Speaker 2>have the possibility to have matter in it? We don't know.

0:31:58.120 --> 0:31:59.880
<v Speaker 2>We don't even know what that would mean, right, because

0:31:59.880 --> 0:32:02.360
<v Speaker 2>you can't have things in it. What does distance really mean?

0:32:02.400 --> 0:32:05.000
<v Speaker 2>If space is by definition empty, distance is sort of

0:32:05.040 --> 0:32:08.200
<v Speaker 2>defined to be between two locations, right, So that would

0:32:08.200 --> 0:32:10.840
<v Speaker 2>be like a whole new kind of space, one that

0:32:10.840 --> 0:32:13.320
<v Speaker 2>doesn't even have the capacity to have stuff in it.

0:32:13.840 --> 0:32:16.080
<v Speaker 1>But that does a math allow for it, or does

0:32:16.160 --> 0:32:18.840
<v Speaker 1>a math not only exist, like the math we have

0:32:19.080 --> 0:32:23.640
<v Speaker 1>only exists or is defined in a universe with fields

0:32:23.640 --> 0:32:23.920
<v Speaker 1>in it.

0:32:24.280 --> 0:32:27.160
<v Speaker 2>You could create a conceptual space with no fields in it.

0:32:27.200 --> 0:32:30.040
<v Speaker 2>Sure it's trivial, right, Like, there's no math for it,

0:32:30.160 --> 0:32:33.040
<v Speaker 2>there's nothing in it. Right, So it's just like it's

0:32:33.040 --> 0:32:35.280
<v Speaker 2>like writing nothing on a sheet of paper. That's your theory.

0:32:38.680 --> 0:32:42.160
<v Speaker 1>Well, yeah, I mean kind of right. Well there's a paper, right,

0:32:42.280 --> 0:32:44.880
<v Speaker 1>the paper exists, you're just not putting an equation in it,

0:32:45.400 --> 0:32:46.720
<v Speaker 1>or you're writing zero in it.

0:32:46.800 --> 0:32:49.560
<v Speaker 2>Yeah, zero, right? But what is zero like is that

0:32:49.640 --> 0:32:51.760
<v Speaker 2>you have a field whose value is zero? If you're

0:32:51.760 --> 0:32:55.360
<v Speaker 2>talking about like really true empty of any theoretical content

0:32:55.520 --> 0:32:59.480
<v Speaker 2>that can exist. Theoretically, it doesn't describe anything in our universe. Right,

0:32:59.760 --> 0:33:02.720
<v Speaker 2>All these concept have to make contact with reality. So

0:33:02.840 --> 0:33:05.520
<v Speaker 2>our best description of reality as we see it out

0:33:05.560 --> 0:33:07.760
<v Speaker 2>there is space that always has fields in it, and

0:33:07.800 --> 0:33:11.400
<v Speaker 2>those fields are never at zero energy. We've never discovered

0:33:11.440 --> 0:33:16.120
<v Speaker 2>any evidence for fieldless space. Theoretically you can make that concept, sure,

0:33:16.560 --> 0:33:18.160
<v Speaker 2>but we don't think it describes reality.

0:33:18.720 --> 0:33:20.240
<v Speaker 1>I see. So I think what you're saying is that

0:33:20.280 --> 0:33:23.600
<v Speaker 1>the universe that we see out there has fields in it,

0:33:24.240 --> 0:33:27.320
<v Speaker 1>and therefore there's no such thing as perfect nothingness because

0:33:27.400 --> 0:33:28.840
<v Speaker 1>everything we see has fields in it.

0:33:28.960 --> 0:33:31.680
<v Speaker 2>Yeah, if perfect nothingness as things without fields, then we

0:33:31.720 --> 0:33:34.320
<v Speaker 2>don't think that exists. In the universe. Every chunk of

0:33:34.400 --> 0:33:37.960
<v Speaker 2>space has those fields, and those fields have some zero

0:33:38.120 --> 0:33:43.000
<v Speaker 2>point energy, some minimum fuzziness, some oscillation to them. For example,

0:33:43.040 --> 0:33:45.240
<v Speaker 2>the Higgs field feels all of space, and the Higgs

0:33:45.240 --> 0:33:48.520
<v Speaker 2>field is sort of weirdly stuck at high energy, so

0:33:48.520 --> 0:33:51.160
<v Speaker 2>it's not a trivial amount of energy that's in space

0:33:51.480 --> 0:33:52.840
<v Speaker 2>even when there's no matter in it.

0:33:53.440 --> 0:33:55.800
<v Speaker 1>But I think what you mean by like everywhere there

0:33:55.840 --> 0:33:58.160
<v Speaker 1>has this little bit of energy to it, you don't

0:33:58.200 --> 0:34:00.880
<v Speaker 1>mean like there's actually energy there. I think what you

0:34:00.920 --> 0:34:03.640
<v Speaker 1>mean is that there's kind of like the potential for

0:34:03.720 --> 0:34:06.480
<v Speaker 1>there to be things in it, or like the universe

0:34:06.840 --> 0:34:10.520
<v Speaker 1>leans towards stuff being there.

0:34:10.640 --> 0:34:13.919
<v Speaker 2>No, I mean there's literally energy in space. The Higgs field,

0:34:14.000 --> 0:34:17.880
<v Speaker 2>for example, filled space, and it has a high potential energy.

0:34:17.960 --> 0:34:20.280
<v Speaker 2>Even if there are no particles there. There is energy

0:34:20.320 --> 0:34:22.680
<v Speaker 2>in the configuration of the field itself.

0:34:22.760 --> 0:34:24.680
<v Speaker 1>That's what I mean. I think you said it has

0:34:24.680 --> 0:34:27.759
<v Speaker 1>the potential to do stuff it's a potential energy. It's

0:34:27.800 --> 0:34:29.760
<v Speaker 1>not like a little photon floating out there in space.

0:34:29.800 --> 0:34:32.560
<v Speaker 2>That's right, it's potential energy exactly. It's like if you

0:34:32.600 --> 0:34:35.040
<v Speaker 2>mentioned a guitar string. Somebody has pulled the guitar string

0:34:35.080 --> 0:34:37.279
<v Speaker 2>away from its relaxed state and it's taught, so it's

0:34:37.280 --> 0:34:40.040
<v Speaker 2>storing energy in that. It's not moving. There's no kinetic

0:34:40.239 --> 0:34:43.040
<v Speaker 2>energy right now. It's not oscillating, but it's held in

0:34:43.080 --> 0:34:46.120
<v Speaker 2>a configuration that has energy. If somebody was to release it,

0:34:46.120 --> 0:34:48.680
<v Speaker 2>it would vibrate and make a noise. Right. The Higgs

0:34:48.719 --> 0:34:51.360
<v Speaker 2>field is just like that. It's held in some configuration

0:34:51.440 --> 0:34:54.680
<v Speaker 2>that stores a lot of energy, and that's potential energy.

0:34:54.800 --> 0:34:57.239
<v Speaker 2>But every field has some energy in it, not even

0:34:57.320 --> 0:34:59.800
<v Speaker 2>just the Higgs field, Like the electromagnetic field that feels

0:34:59.800 --> 0:35:02.560
<v Speaker 2>space is held in a non zero value and that's

0:35:02.600 --> 0:35:06.640
<v Speaker 2>not just potential energy. That's like actually thrumming with kinetic energy.

0:35:06.760 --> 0:35:08.839
<v Speaker 1>Thruw I mean in a quantum says that. I think

0:35:08.960 --> 0:35:11.840
<v Speaker 1>what you mean is like there's like quantum particles popping

0:35:11.880 --> 0:35:13.399
<v Speaker 1>in and out of existence. Is that what you mean?

0:35:13.719 --> 0:35:16.359
<v Speaker 2>Not enough energy to make a real particle, But the

0:35:16.400 --> 0:35:19.440
<v Speaker 2>field itself has energy. It is vibrating. You can think

0:35:19.440 --> 0:35:22.480
<v Speaker 2>of these fields as having kinetic energy and potential energy,

0:35:22.680 --> 0:35:24.959
<v Speaker 2>just like a string, right, which slides back and forth

0:35:25.000 --> 0:35:27.960
<v Speaker 2>between having kinetic and potential energy as it oscillates. So

0:35:28.000 --> 0:35:32.080
<v Speaker 2>these fields have actual energy, not enough to make a particle. Right,

0:35:32.120 --> 0:35:35.200
<v Speaker 2>The lowest energy state of these things is not one particle.

0:35:35.239 --> 0:35:38.359
<v Speaker 2>It's zero particles, but not zero energy.

0:35:38.320 --> 0:35:39.719
<v Speaker 1>All right, So then what does that mean for the

0:35:39.760 --> 0:35:42.200
<v Speaker 1>idea of a vacuum. Means that in our universe you

0:35:42.360 --> 0:35:43.840
<v Speaker 1>can have a perfect vacuum.

0:35:43.960 --> 0:35:47.560
<v Speaker 2>In our universe, we define sort of theoretical concept is

0:35:47.840 --> 0:35:51.040
<v Speaker 2>the most relaxed state of all the fields. That's sort

0:35:51.040 --> 0:35:53.400
<v Speaker 2>of like how we define a vacuum. We don't define

0:35:53.400 --> 0:35:55.480
<v Speaker 2>it to be like the theoretical minimum where all the

0:35:55.480 --> 0:35:58.560
<v Speaker 2>fields are a zero, because that's not theoretically possible. We

0:35:58.640 --> 0:36:01.240
<v Speaker 2>consider this sort of state of space as we understand

0:36:01.320 --> 0:36:03.279
<v Speaker 2>it and try to imagine what would be the most

0:36:03.400 --> 0:36:07.319
<v Speaker 2>relaxed configuration that all the field could get into. And

0:36:07.400 --> 0:36:09.960
<v Speaker 2>we now know that that's not at zero. But what's

0:36:10.000 --> 0:36:13.160
<v Speaker 2>interesting is that there might be multiple ways for the

0:36:13.200 --> 0:36:16.480
<v Speaker 2>field to relax. There might be a few stable configurations.

0:36:16.880 --> 0:36:19.120
<v Speaker 2>One of those would be the true vacuum. The actual

0:36:19.280 --> 0:36:22.920
<v Speaker 2>lowest possible state. The other ones would be false vacua

0:36:23.080 --> 0:36:25.880
<v Speaker 2>like places that space gets stuck as it's trying to

0:36:25.920 --> 0:36:27.920
<v Speaker 2>relax down to zero and it ends up in a

0:36:28.000 --> 0:36:31.560
<v Speaker 2>stable configuration that's not actually the lowest energy state.

0:36:31.800 --> 0:36:33.399
<v Speaker 1>I think what you're saying is that, like even if

0:36:33.400 --> 0:36:34.960
<v Speaker 1>you go out there in the middle of space, or

0:36:34.960 --> 0:36:37.320
<v Speaker 1>even if you create one, like you make a box

0:36:37.640 --> 0:36:40.400
<v Speaker 1>where nothing can get in it and there's no particles,

0:36:40.440 --> 0:36:43.160
<v Speaker 1>you see, no particles in it, there is still a

0:36:43.160 --> 0:36:45.320
<v Speaker 1>little bit of like thrumbing or a little bit of

0:36:45.600 --> 0:36:50.880
<v Speaker 1>vibration of the fields in that space not creating fully particles,

0:36:50.880 --> 0:36:53.000
<v Speaker 1>Like there's not enough there to actually pop out a

0:36:53.040 --> 0:36:55.520
<v Speaker 1>particle with that you can see and interact with. But

0:36:55.680 --> 0:36:58.640
<v Speaker 1>there's like, you know, half a particle forming and then

0:36:58.680 --> 0:37:01.799
<v Speaker 1>it's gone. There's a quarter of a particle Thereah, but

0:37:01.920 --> 0:37:03.720
<v Speaker 1>it's gone. Kind of situation, right.

0:37:03.600 --> 0:37:05.760
<v Speaker 2>Yeah, And you just intuited your way from the field

0:37:05.760 --> 0:37:08.319
<v Speaker 2>description to the particles cold description, Like what does the

0:37:08.440 --> 0:37:10.640
<v Speaker 2>energy of this field mean if it's not enough to

0:37:10.680 --> 0:37:13.319
<v Speaker 2>have an actual particle there. Well, it's sort of like

0:37:13.520 --> 0:37:15.440
<v Speaker 2>you know the particles exist, and that they don't they

0:37:15.440 --> 0:37:18.400
<v Speaker 2>pop in and out of existence. That's replacing the idea

0:37:18.440 --> 0:37:21.080
<v Speaker 2>of a field with these virtual particles that have some

0:37:21.160 --> 0:37:24.320
<v Speaker 2>weird energy from space itself and not enough to really

0:37:24.360 --> 0:37:26.160
<v Speaker 2>exist in the sense of like it could hang out

0:37:26.239 --> 0:37:28.279
<v Speaker 2>and you could leave the electron there and come back

0:37:28.320 --> 0:37:30.600
<v Speaker 2>a billion years later it would still be there. These

0:37:30.640 --> 0:37:33.279
<v Speaker 2>are virtual particles. That's sort of intuitive way to think

0:37:33.320 --> 0:37:35.879
<v Speaker 2>about what a virtual particle is, just like another way

0:37:35.920 --> 0:37:37.960
<v Speaker 2>to think about a field. When the field doesn't have

0:37:38.040 --> 0:37:40.359
<v Speaker 2>enough energy to make real particles, it might have enough

0:37:40.400 --> 0:37:41.800
<v Speaker 2>to make virtual particles.

0:37:42.000 --> 0:37:44.719
<v Speaker 1>All right, well, let's get into the idea of what

0:37:44.760 --> 0:37:47.680
<v Speaker 1>it would mean if you actually created a real vacuum,

0:37:47.880 --> 0:37:49.880
<v Speaker 1>and it has to do with this concept of a

0:37:50.080 --> 0:37:52.800
<v Speaker 1>fields relaxing. How relax can you make a field? What

0:37:52.920 --> 0:37:54.879
<v Speaker 1>sort of medication you need to give it in order

0:37:54.920 --> 0:37:57.759
<v Speaker 1>for it to finally relax. We'll dig into that, but

0:37:57.800 --> 0:38:13.120
<v Speaker 1>first let's take another quick break. All right, we're talking

0:38:13.120 --> 0:38:16.040
<v Speaker 1>about nothing today. This is the episode about nothing.

0:38:16.200 --> 0:38:17.800
<v Speaker 2>This is the Seinfeld of podcast.

0:38:18.600 --> 0:38:22.080
<v Speaker 1>That's right. I'll be Kramer and you be Which one

0:38:22.120 --> 0:38:24.839
<v Speaker 1>of us is Kramer, Which one of them is George? Consensus.

0:38:24.840 --> 0:38:26.960
<v Speaker 2>I think you're definitely more Kramer and I'm more George.

0:38:26.960 --> 0:38:30.240
<v Speaker 2>For sure. I always wanted to be an architect.

0:38:31.280 --> 0:38:34.080
<v Speaker 1>Yeah, I thought I was a comedian. Wait a minute,

0:38:34.280 --> 0:38:36.359
<v Speaker 1>but we were talking about nothing and the idea of

0:38:36.400 --> 0:38:39.360
<v Speaker 1>nothing and whether it's possible to have nothing in the universe,

0:38:39.400 --> 0:38:42.279
<v Speaker 1>and it sounds like that's not really possible. In the

0:38:42.360 --> 0:38:46.200
<v Speaker 1>universe that we see and experience, there are things called

0:38:46.280 --> 0:38:49.880
<v Speaker 1>quantum fields and so you which occupied all of space

0:38:50.000 --> 0:38:53.360
<v Speaker 1>and which has kind of inherent energy to it. So

0:38:53.400 --> 0:38:56.600
<v Speaker 1>there's really no trunk of space out there that has

0:38:56.719 --> 0:38:57.360
<v Speaker 1>zero energy.

0:38:57.760 --> 0:39:00.760
<v Speaker 2>Yeah, that's right. Space has these fields and they're always

0:39:00.800 --> 0:39:03.520
<v Speaker 2>wiggling at least a little bit. And so instead of

0:39:03.600 --> 0:39:07.560
<v Speaker 2>thinking about true zeroness of space, which we think is impossible,

0:39:07.640 --> 0:39:11.280
<v Speaker 2>physicists like to think about the minimum energy state of space.

0:39:11.320 --> 0:39:13.960
<v Speaker 2>That's what we call the vacuum, what happens when space

0:39:14.000 --> 0:39:16.720
<v Speaker 2>relaxes as much as it's theoretically allowed.

0:39:17.000 --> 0:39:19.600
<v Speaker 1>Okay, so then I guess we're this more like maximum

0:39:19.680 --> 0:39:22.960
<v Speaker 1>vacuum of the universe. Maybe not the perfect vacuum, but

0:39:23.000 --> 0:39:25.960
<v Speaker 1>the most vacuuminess that the universe can get.

0:39:26.160 --> 0:39:29.360
<v Speaker 2>Yeah, the vacuumiist. But I like that phrase maximum vacuum.

0:39:29.360 --> 0:39:33.840
<v Speaker 2>That sounds cool like an eighties band starring Max headroom.

0:39:34.280 --> 0:39:37.839
<v Speaker 1>Yeah with long long hair, Yeah, that might be out

0:39:37.880 --> 0:39:39.040
<v Speaker 1>of our reach at our age.

0:39:39.200 --> 0:39:43.000
<v Speaker 2>And to understand what's actually achievable, like how you can

0:39:43.080 --> 0:39:46.120
<v Speaker 2>really relax space itself, you have to understand like how

0:39:46.160 --> 0:39:48.319
<v Speaker 2>the fields wiggle and how they interact with each other,

0:39:48.360 --> 0:39:51.239
<v Speaker 2>how energy slashes back and forth. It's sort of like

0:39:51.280 --> 0:39:52.880
<v Speaker 2>you know when you lie down to take a nap

0:39:52.920 --> 0:39:55.960
<v Speaker 2>and you feel like, okay, I'm totally relaxed. Then you discover,

0:39:56.239 --> 0:39:58.960
<v Speaker 2>oh no, I'm actually holding this muscle tot and you

0:39:59.120 --> 0:40:01.480
<v Speaker 2>learn to relax that, to relax that, and you only

0:40:01.520 --> 0:40:03.680
<v Speaker 2>really ever fall asleep when all of your muscles are

0:40:03.719 --> 0:40:06.359
<v Speaker 2>fully relaxed in their lowest energy state.

0:40:06.760 --> 0:40:09.040
<v Speaker 1>Well, I guess maybe a question is there are fields

0:40:09.080 --> 0:40:11.520
<v Speaker 1>that have zero energy to them or not? Or do

0:40:11.640 --> 0:40:14.439
<v Speaker 1>all quantum fields have some inherent energy to them?

0:40:14.560 --> 0:40:17.080
<v Speaker 2>No quantum fields can have zero energy in them. It's

0:40:17.120 --> 0:40:21.160
<v Speaker 2>just an inherent property of any quantum object that cannot

0:40:21.200 --> 0:40:22.360
<v Speaker 2>have zero energy.

0:40:22.440 --> 0:40:22.759
<v Speaker 1>Why not.

0:40:23.040 --> 0:40:25.600
<v Speaker 2>There's the mathematical approach, which is like you look at

0:40:25.640 --> 0:40:27.960
<v Speaker 2>the shorter your equation, you try to solve it. The

0:40:28.000 --> 0:40:31.480
<v Speaker 2>minimum energy solution is not at zero. The intuitive way

0:40:31.480 --> 0:40:34.080
<v Speaker 2>to think about it is the heisember concertainty principle. Right,

0:40:34.120 --> 0:40:37.879
<v Speaker 2>If you accept that things have a minimum uncertainty to them,

0:40:38.120 --> 0:40:41.879
<v Speaker 2>then having zero energy would perfectly define its momentum and

0:40:41.960 --> 0:40:44.560
<v Speaker 2>its location. At the same time, you would know too

0:40:44.640 --> 0:40:47.839
<v Speaker 2>much about it. So in order to maintain the fuzziness

0:40:47.840 --> 0:40:50.360
<v Speaker 2>of the universe, these quantum fields have to be buzzing

0:40:50.440 --> 0:40:51.000
<v Speaker 2>a little bit.

0:40:51.440 --> 0:40:55.240
<v Speaker 1>WHOA that seems to get really philosophical.

0:40:54.760 --> 0:40:57.560
<v Speaker 2>Every time you try to understand quantum mechanics intuitively, you

0:40:57.680 --> 0:41:00.439
<v Speaker 2>got to reach for philosophy. That's really all we have.

0:41:00.960 --> 0:41:03.600
<v Speaker 2>You know, quantum mechanics has the beautiful mathematics which gives

0:41:03.640 --> 0:41:07.080
<v Speaker 2>you answers. But you want like intuitive understanding, then it's

0:41:07.120 --> 0:41:07.960
<v Speaker 2>all philosophy.

0:41:08.239 --> 0:41:10.040
<v Speaker 1>But what do you mean, Like you can't have uncertainty

0:41:10.200 --> 0:41:12.800
<v Speaker 1>with a perfect vacuum? Like could you have a field

0:41:12.840 --> 0:41:15.759
<v Speaker 1>that has zero average energy but it kind of like

0:41:16.160 --> 0:41:18.600
<v Speaker 1>has a negative state of being. I don't know, I

0:41:18.640 --> 0:41:20.360
<v Speaker 1>don't know what I'm talking about, But why can't you

0:41:20.400 --> 0:41:23.400
<v Speaker 1>have fuzziness and a zero average.

0:41:23.120 --> 0:41:26.759
<v Speaker 2>The value of the field is zero on average, but

0:41:26.880 --> 0:41:29.239
<v Speaker 2>the energy is not zero the same way that like

0:41:29.280 --> 0:41:31.839
<v Speaker 2>when a string vibrates on the guitar. If you took

0:41:31.960 --> 0:41:34.640
<v Speaker 2>pictures of where the string was and you average it's location.

0:41:34.760 --> 0:41:38.360
<v Speaker 2>Its average location is at the most relaxed state, or

0:41:38.360 --> 0:41:40.960
<v Speaker 2>at a straight string. You took any point on that

0:41:41.000 --> 0:41:43.840
<v Speaker 2>string and asks like, where is it on average? On average,

0:41:43.880 --> 0:41:45.960
<v Speaker 2>it's at its relaxed state. It's at the middle point

0:41:46.000 --> 0:41:48.879
<v Speaker 2>where the string is straight. But it's oscillating still, right,

0:41:49.120 --> 0:41:52.080
<v Speaker 2>it's still moving. So these fields can have energy while

0:41:52.120 --> 0:41:54.000
<v Speaker 2>their average value is still at zero.

0:41:54.280 --> 0:41:57.160
<v Speaker 1>And so what would happen if a string had no energy.

0:41:56.880 --> 0:41:59.160
<v Speaker 2>Well, a classical string can have no energy, right, And

0:41:59.200 --> 0:42:02.600
<v Speaker 2>that means you know exactly its location and exactly it's momentum.

0:42:02.760 --> 0:42:06.000
<v Speaker 2>It's zero momentum. But a quantum object can't do that.

0:42:06.120 --> 0:42:08.880
<v Speaker 2>You can't know both of those things simultaneously about a

0:42:08.960 --> 0:42:11.319
<v Speaker 2>quantum object. And it's not just that we can't know it.

0:42:11.360 --> 0:42:15.920
<v Speaker 2>Then information does not exist, cannot exist. It's not Noah bowl,

0:42:16.480 --> 0:42:18.480
<v Speaker 2>it's not determined.

0:42:17.880 --> 0:42:19.520
<v Speaker 1>Which wouldn't be a quantum object.

0:42:19.640 --> 0:42:22.320
<v Speaker 2>Oh yeah, sure, if you want to overthrow quantum mechanics,

0:42:22.320 --> 0:42:25.480
<v Speaker 2>then yes, you can have objects with zero energy. So

0:42:25.600 --> 0:42:29.040
<v Speaker 2>classical fields definitely can. But all evidence suggests that all

0:42:29.040 --> 0:42:32.040
<v Speaker 2>the fields we know about other than gravity at least

0:42:32.480 --> 0:42:34.840
<v Speaker 2>are quantum fields. They have quantum properties.

0:42:34.960 --> 0:42:37.880
<v Speaker 1>Wait, are you saying gravity is a non quantum field.

0:42:38.000 --> 0:42:40.520
<v Speaker 2>Well, our theory of gravity is a classical one, right,

0:42:40.680 --> 0:42:43.839
<v Speaker 2>and suggests that space can have zero curvature to it

0:42:44.200 --> 0:42:46.520
<v Speaker 2>and all sorts of stuff. We don't have a quantum

0:42:46.560 --> 0:42:49.400
<v Speaker 2>theory of gravity, so yeah, we have an only classical

0:42:49.480 --> 0:42:53.200
<v Speaker 2>understanding of gravity. We're not successfully quantized gravity. We don't

0:42:53.200 --> 0:42:55.120
<v Speaker 2>even know if gravity is a field or if it's

0:42:55.160 --> 0:42:57.479
<v Speaker 2>just like the curvature of space. So that's not something

0:42:57.600 --> 0:42:59.920
<v Speaker 2>we understand at all. But all the fields that we

0:42:59.920 --> 0:43:03.160
<v Speaker 2>have been able to probe and understand, electromagnetism and the

0:43:03.160 --> 0:43:05.960
<v Speaker 2>weak force, a strong force, these are definitely all quantum

0:43:06.000 --> 0:43:08.839
<v Speaker 2>fields and so they definitely cannot have zero energy. Same

0:43:08.880 --> 0:43:11.560
<v Speaker 2>with the Higgs field, also definitely a quantum field.

0:43:11.960 --> 0:43:13.960
<v Speaker 1>So wait, then, are you saying that if gravity is

0:43:14.000 --> 0:43:16.719
<v Speaker 1>not a quantum field, then you can have a non

0:43:16.800 --> 0:43:17.560
<v Speaker 1>quantum field.

0:43:17.800 --> 0:43:20.799
<v Speaker 2>It's possible that gravity is a non quantum field. Yeah,

0:43:20.840 --> 0:43:23.880
<v Speaker 2>we just don't really understand gravity. I remember that Einstein's

0:43:23.880 --> 0:43:26.640
<v Speaker 2>theory of gravity was developed basically at the same time

0:43:26.719 --> 0:43:28.840
<v Speaker 2>as quantum mechanics, and so he wrote it as a

0:43:28.920 --> 0:43:32.520
<v Speaker 2>classical theory. It makes all sorts of assumptions about the universe.

0:43:32.760 --> 0:43:35.359
<v Speaker 2>You know that you can have smooth, continuous paths that

0:43:35.400 --> 0:43:38.520
<v Speaker 2>you can know precisely the velocity and location of objects,

0:43:38.520 --> 0:43:40.360
<v Speaker 2>things that we don't think are true about the universe.

0:43:40.600 --> 0:43:43.240
<v Speaker 2>He built those into his theory, and yet it works

0:43:43.440 --> 0:43:46.399
<v Speaker 2>in every location where we can test it. So it's

0:43:46.400 --> 0:43:49.080
<v Speaker 2>a deep question in modern physics, like how do we

0:43:49.120 --> 0:43:52.440
<v Speaker 2>reconcile general relativity with quantum mechanics. But yeah, it's possible

0:43:52.520 --> 0:43:56.160
<v Speaker 2>that gravity is a field that's a classical field that

0:43:56.239 --> 0:43:57.680
<v Speaker 2>could relax down to zero.

0:43:57.880 --> 0:43:59.400
<v Speaker 1>I'm just trying to dig into what you say. I

0:43:59.400 --> 0:44:01.880
<v Speaker 1>mean when you say it's not possible, what you actually

0:44:01.960 --> 0:44:05.800
<v Speaker 1>mean is like it's not allowed under or the quantum

0:44:05.840 --> 0:44:08.200
<v Speaker 1>view of the universe, which may or may not be true.

0:44:08.320 --> 0:44:11.200
<v Speaker 2>Yeah, that's true. It might be that the final unification

0:44:11.440 --> 0:44:15.200
<v Speaker 2>and understanding of the bigger picture of physics involves an

0:44:15.200 --> 0:44:18.719
<v Speaker 2>overthrowing of quantum mechanics rather than general relativity. Maybe generativity

0:44:18.760 --> 0:44:21.799
<v Speaker 2>is right, and space is a classical backdrop in some way,

0:44:22.040 --> 0:44:25.000
<v Speaker 2>but in our current understanding of space at least it

0:44:25.000 --> 0:44:27.960
<v Speaker 2>contains these quantum fields which can't go down to zero.

0:44:28.280 --> 0:44:29.920
<v Speaker 2>But yeah, that could be all wrong.

0:44:30.160 --> 0:44:33.840
<v Speaker 1>Okay, Well, let's get back to our discussion vacuums. So

0:44:33.840 --> 0:44:36.480
<v Speaker 1>you're saying that maybe what we can talk about is

0:44:36.600 --> 0:44:39.480
<v Speaker 1>maximum vacuum of the universe, which is when these fields

0:44:39.520 --> 0:44:42.680
<v Speaker 1>relax down to the lowest level. And you're saying that

0:44:42.719 --> 0:44:45.760
<v Speaker 1>there's kind of different ways for these fields to relax,

0:44:46.320 --> 0:44:50.280
<v Speaker 1>Like there's meditation, there's drinking chamma meal.

0:44:50.120 --> 0:44:54.799
<v Speaker 2>Tea, meditation and medication exactly. Well, you know, this sort

0:44:54.800 --> 0:44:58.880
<v Speaker 2>of story of the universe is relaxation. The universe is expanding,

0:44:58.960 --> 0:45:01.359
<v Speaker 2>which means it's getting more elude, which means it's getting

0:45:01.560 --> 0:45:06.080
<v Speaker 2>lower temperature. Right, it's cooling down. As the universe expands,

0:45:06.120 --> 0:45:08.840
<v Speaker 2>the matter gets more and more sparse, and so the

0:45:08.960 --> 0:45:11.399
<v Speaker 2>energy in those fields is going down, down, down, down down.

0:45:11.680 --> 0:45:14.080
<v Speaker 2>So we think about the whole universe as relaxing. All

0:45:14.120 --> 0:45:16.640
<v Speaker 2>the common fields are sort of chill and out heading

0:45:16.680 --> 0:45:17.640
<v Speaker 2>towards zero.

0:45:17.840 --> 0:45:19.480
<v Speaker 1>Wait, what does that mean? Does that mean like a

0:45:19.800 --> 0:45:21.719
<v Speaker 1>field can have a lot of energy and it can

0:45:21.840 --> 0:45:22.840
<v Speaker 1>have a little bit of energy.

0:45:23.040 --> 0:45:25.120
<v Speaker 2>Yeah, fields in the center of the sun have a

0:45:25.160 --> 0:45:28.520
<v Speaker 2>lot of energy. Fields out in intergalactic space have much

0:45:28.560 --> 0:45:29.280
<v Speaker 2>less energy.

0:45:29.600 --> 0:45:32.520
<v Speaker 1>No, But I mean, like as a concept of a field, right, like.

0:45:32.840 --> 0:45:36.120
<v Speaker 2>Well, having multiple particles just means that field is wiggling

0:45:36.200 --> 0:45:39.239
<v Speaker 2>more like the field wiggles, that's one particle. The field

0:45:39.239 --> 0:45:42.160
<v Speaker 2>wiggles more, that's two particles. Field wiggles even more, that's

0:45:42.160 --> 0:45:43.200
<v Speaker 2>a billion particles.

0:45:43.440 --> 0:45:45.439
<v Speaker 1>I guess I was referring to this idea that maybe

0:45:45.520 --> 0:45:47.719
<v Speaker 1>there's a chunk in space out there with nothing in

0:45:47.760 --> 0:45:50.640
<v Speaker 1>it that has fields in it that are vibrating and

0:45:50.680 --> 0:45:53.680
<v Speaker 1>have energy to it. Can that energy be different values?

0:45:54.120 --> 0:45:56.399
<v Speaker 2>So it depends on how space cools, right, It's sort

0:45:56.400 --> 0:45:58.200
<v Speaker 2>of like making a sou fle. You've got to get

0:45:58.239 --> 0:46:01.440
<v Speaker 2>it to that special configuration. So the universe is cooling,

0:46:01.520 --> 0:46:04.440
<v Speaker 2>time is going on, space is relaxing, And then I

0:46:04.440 --> 0:46:06.560
<v Speaker 2>think the question you're asking is like, could it relax

0:46:06.600 --> 0:46:09.239
<v Speaker 2>into different values? Could you have like one state of

0:46:09.360 --> 0:46:12.160
<v Speaker 2>energy over here, another state of lower energy over there?

0:46:12.360 --> 0:46:14.839
<v Speaker 1>Yeah, Like can the electron feel when it relaxes down

0:46:14.880 --> 0:46:18.160
<v Speaker 1>to its minimum? Can it relax down to point one

0:46:18.400 --> 0:46:21.560
<v Speaker 1>or point three or point four or when it relaxes

0:46:21.600 --> 0:46:23.760
<v Speaker 1>there's just one possible relaxation met.

0:46:23.920 --> 0:46:27.200
<v Speaker 2>So almost all the fields relax in a very simple way,

0:46:27.239 --> 0:46:30.120
<v Speaker 2>which is heading towards zero and hitting that minimum, so

0:46:30.160 --> 0:46:32.440
<v Speaker 2>that their average value is zero and they have the

0:46:32.520 --> 0:46:35.360
<v Speaker 2>minimum energy, and that should be the same everywhere in

0:46:35.360 --> 0:46:38.799
<v Speaker 2>the universe. But one field, the Higgs field, has some

0:46:38.840 --> 0:46:42.000
<v Speaker 2>weird wiggles in it and it gets stuck as it cools.

0:46:42.040 --> 0:46:45.080
<v Speaker 2>So the whole universe is cooling down. Everything is settling down,

0:46:45.120 --> 0:46:47.920
<v Speaker 2>sort of rolling towards the bottom of a valley, but

0:46:47.920 --> 0:46:50.560
<v Speaker 2>the Higgs field gets stuck in this false vacuum. Is

0:46:50.600 --> 0:46:53.280
<v Speaker 2>a large amount of energy stuck in it high potential

0:46:53.360 --> 0:46:56.800
<v Speaker 2>energy configuration. While everything else like rolled to the bottom

0:46:56.800 --> 0:46:58.600
<v Speaker 2>of a canyon. It got stuck sort of like on

0:46:58.640 --> 0:47:01.799
<v Speaker 2>a shelf on the canyon wall. So the Higgs field

0:47:01.920 --> 0:47:04.040
<v Speaker 2>is different from all the other fields. It's harder for

0:47:04.080 --> 0:47:06.800
<v Speaker 2>it to relax because the shape of its potential energy.

0:47:07.160 --> 0:47:09.200
<v Speaker 1>I think what you mean is like like if each

0:47:09.320 --> 0:47:12.719
<v Speaker 1>field is like the string and a guitar. All of

0:47:12.760 --> 0:47:16.160
<v Speaker 1>the fields kind of settled down to kind of a

0:47:16.200 --> 0:47:19.200
<v Speaker 1>minimum vibration, but the Higgs field is kind of stuck

0:47:19.200 --> 0:47:22.840
<v Speaker 1>in this kind of high vibration state.

0:47:23.000 --> 0:47:25.760
<v Speaker 2>It's not actually vibrating, and it has high potential energy.

0:47:26.120 --> 0:47:29.200
<v Speaker 2>So while everything else settled down to like the lowest

0:47:29.200 --> 0:47:33.000
<v Speaker 2>possible vibration, it got like stuck in this configuration where

0:47:33.000 --> 0:47:35.960
<v Speaker 2>somebody's pulling it really hard, and it's taught, it's not vibrating,

0:47:36.000 --> 0:47:37.960
<v Speaker 2>there's not a lot of kinetic energy, has a lot

0:47:38.000 --> 0:47:40.160
<v Speaker 2>of potential energy. So the Higgs field sort of like

0:47:40.200 --> 0:47:42.239
<v Speaker 2>got stuck on a bump on the side of your

0:47:42.280 --> 0:47:45.760
<v Speaker 2>guitar and it's pulled sideways and taught and stuck there.

0:47:46.960 --> 0:47:49.160
<v Speaker 1>Like there's a certain curve to the string. Maybe I

0:47:49.200 --> 0:47:50.040
<v Speaker 1>don't know, And so.

0:47:50.040 --> 0:47:52.960
<v Speaker 2>One question is like, is that the true vacuum or

0:47:53.000 --> 0:47:54.880
<v Speaker 2>is that a false vacuum. Is it possible for the

0:47:54.920 --> 0:47:57.640
<v Speaker 2>Higgs field to relax to a lower state, And we've

0:47:57.640 --> 0:47:59.640
<v Speaker 2>talked about that several times, like if the Higgs field

0:47:59.640 --> 0:48:02.399
<v Speaker 2>would collac to a lower potential energy configuration, that would

0:48:02.480 --> 0:48:05.400
<v Speaker 2>change the nature of physics in our universe, and you know,

0:48:05.480 --> 0:48:07.360
<v Speaker 2>all of our atoms would explode at the speed of

0:48:07.440 --> 0:48:09.719
<v Speaker 2>light and all sorts of crazy stuff. But we think

0:48:09.800 --> 0:48:13.680
<v Speaker 2>that probably there are multiple possible vacuum states, and the

0:48:13.760 --> 0:48:16.239
<v Speaker 2>Higgs field is stuck in sort of a false vacuum,

0:48:16.360 --> 0:48:19.279
<v Speaker 2>and the true vacuum is a lower energy configuration that

0:48:19.360 --> 0:48:21.600
<v Speaker 2>it can't quite get to. It's sort of stuck in this.

0:48:21.640 --> 0:48:25.680
<v Speaker 1>Vacuum m like the Higgs field can relax to maybe lower,

0:48:25.719 --> 0:48:27.040
<v Speaker 1>but for some reason it's not.

0:48:27.360 --> 0:48:29.280
<v Speaker 2>Yeah, somebody's holding on to that string.

0:48:29.560 --> 0:48:33.160
<v Speaker 1>It's the finger of God or the God's pick.

0:48:35.960 --> 0:48:39.040
<v Speaker 2>Maybe God's just in a dad band and that defines

0:48:39.040 --> 0:48:39.920
<v Speaker 2>the nature of the universe.

0:48:39.960 --> 0:48:42.799
<v Speaker 1>Yeah, there you go. That's right. And his dad is.

0:48:42.760 --> 0:48:44.960
<v Speaker 2>Called maximum vacuum.

0:48:45.600 --> 0:48:51.000
<v Speaker 1>Maximum vacuum. That's right. Now, does God play all the

0:48:51.080 --> 0:48:54.839
<v Speaker 1>instruments or is he like a one man dad. It's

0:48:54.880 --> 0:48:57.160
<v Speaker 1>like the Holy Quick quintet, you know.

0:48:57.640 --> 0:48:59.719
<v Speaker 2>But then all members are actually part of the one.

0:49:00.360 --> 0:49:03.160
<v Speaker 2>I don't have enough theological background to comment on that

0:49:03.480 --> 0:49:04.640
<v Speaker 2>without offending.

0:49:04.239 --> 0:49:08.520
<v Speaker 1>People anyways, So you were saying that maybe like we're

0:49:08.520 --> 0:49:12.120
<v Speaker 1>not in the most vacuumus of vacuums that the universe

0:49:12.160 --> 0:49:13.880
<v Speaker 1>can be in, and thankfully.

0:49:13.520 --> 0:49:16.000
<v Speaker 2>All space out there probably has some particles in it.

0:49:16.440 --> 0:49:19.040
<v Speaker 2>Even if you were able to remove particles from space,

0:49:19.560 --> 0:49:21.640
<v Speaker 2>you would have space in this sort of Higgs field

0:49:21.640 --> 0:49:24.600
<v Speaker 2>that's stuck at a high potential energy. And so yeah,

0:49:24.640 --> 0:49:28.120
<v Speaker 2>probably nothing out there currently is even capable of getting

0:49:28.120 --> 0:49:31.080
<v Speaker 2>to the maximum vacuum state that our kind of space

0:49:31.280 --> 0:49:33.719
<v Speaker 2>is technically capable of achieving.

0:49:35.280 --> 0:49:38.000
<v Speaker 1>And thankfully right, because if we ever flip to that

0:49:38.400 --> 0:49:41.520
<v Speaker 1>lower or more vacuum e vacuum, then we're all toast

0:49:41.680 --> 0:49:45.080
<v Speaker 1>like our universe would kind of get upturned and really suck.

0:49:45.719 --> 0:49:48.200
<v Speaker 2>Absolutely. We have a whole episode about what would happen

0:49:48.280 --> 0:49:50.759
<v Speaker 2>if the Higgs field did go to zero, and yeah,

0:49:50.800 --> 0:49:51.840
<v Speaker 2>it would ruin your life.

0:49:51.880 --> 0:49:53.440
<v Speaker 1>On the plus that you wouldn't have to vacuum your

0:49:53.480 --> 0:49:54.040
<v Speaker 1>house anymore.

0:49:54.840 --> 0:49:56.520
<v Speaker 2>It would be automatically vacuumed.

0:49:57.040 --> 0:49:59.800
<v Speaker 1>Just room ba our way to a more blissful existence.

0:50:00.520 --> 0:50:03.160
<v Speaker 1>All right, Well, I think the answer to our question

0:50:03.320 --> 0:50:05.600
<v Speaker 1>of the episode is that a vacuum, it would be

0:50:05.680 --> 0:50:08.759
<v Speaker 1>a spot with nothing in it, not even energy. And

0:50:08.880 --> 0:50:11.040
<v Speaker 1>as far as we know, our universe kind of has

0:50:11.160 --> 0:50:14.080
<v Speaker 1>something in it everywhere, and so a perfect vacuum it's

0:50:14.120 --> 0:50:16.880
<v Speaker 1>not possible, and we have to settle for the eighties

0:50:16.920 --> 0:50:20.160
<v Speaker 1>Coverman maximum vacuum.

0:50:20.280 --> 0:50:23.080
<v Speaker 2>And when physicists talk about vacuums, that's what they mean.

0:50:23.120 --> 0:50:25.320
<v Speaker 2>They mean a chunk of space with no particles in it,

0:50:25.360 --> 0:50:29.400
<v Speaker 2>relaxed to its maximum possible state, which is not zero energy.

0:50:29.840 --> 0:50:32.880
<v Speaker 1>I feel like physicists are settling then, though. Can't they

0:50:32.920 --> 0:50:34.120
<v Speaker 1>be striving for perfection?

0:50:34.400 --> 0:50:36.960
<v Speaker 2>No, we're just defining our achievements as success.

0:50:37.280 --> 0:50:38.800
<v Speaker 1>I see, you're lowering your standards.

0:50:40.600 --> 0:50:46.840
<v Speaker 2>We're redefining success. Everyone gets a trophy exactly, participation vacuum.

0:50:46.920 --> 0:50:48.719
<v Speaker 1>All right, well, I guess the next time you look

0:50:48.719 --> 0:50:52.480
<v Speaker 1>at into the that's of space, think about the idea

0:50:52.520 --> 0:50:55.440
<v Speaker 1>that there is nothing out there that is truly nothing.

0:50:56.040 --> 0:50:59.520
<v Speaker 1>There's always something out there in the universe.

0:51:00.120 --> 0:51:02.200
<v Speaker 2>Nothingness has a lot of something to think.

0:51:02.080 --> 0:51:05.080
<v Speaker 1>About that's not nothing. Well, we hope you enjoyed that.

0:51:05.239 --> 0:51:07.879
<v Speaker 1>Thanks for joining us, see you next time.

0:51:15.800 --> 0:51:18.600
<v Speaker 2>Thanks for listening, and remember that Daniel and Jorge explain

0:51:18.680 --> 0:51:22.680
<v Speaker 2>the Universe is a production of iHeartRadio. For more podcasts

0:51:22.680 --> 0:51:27.320
<v Speaker 2>from iHeartRadio, visit the iHeartRadio app, Apple Podcasts, or wherever

0:51:27.400 --> 0:51:29.120
<v Speaker 2>you listen to your favorite shows.