1 00:00:08,440 --> 00:00:11,200 Speaker 1: Hey, Daniel, did you guys find dark matter yet? Uh? 2 00:00:11,360 --> 00:00:14,640 Speaker 1: Not yet? Still looking It's been what a few decades, 3 00:00:15,160 --> 00:00:17,880 Speaker 1: embarrassingly more than a few. I'm just wondering, you know, 4 00:00:17,960 --> 00:00:20,920 Speaker 1: are you sure you're doing it right? Well, you know, 5 00:00:21,079 --> 00:00:23,239 Speaker 1: I think we're doing our best, but there's always a 6 00:00:23,320 --> 00:00:25,200 Speaker 1: chance were messing it up. Just asking because you know, 7 00:00:25,320 --> 00:00:28,520 Speaker 1: maybe it's time to bring in some engineers to take 8 00:00:28,560 --> 00:00:31,040 Speaker 1: over and help you out. Oh yeah, we could use 9 00:00:31,040 --> 00:00:34,519 Speaker 1: a few cartoonists. Maybe lighten the mood over there. See, 10 00:00:35,000 --> 00:00:54,080 Speaker 1: you need someone to make light of dark matter. H 11 00:00:54,080 --> 00:00:57,560 Speaker 1: I am more handmade cartoonists and the creator of PhD comics. Hi. 12 00:00:57,720 --> 00:01:01,040 Speaker 1: I'm Daniel Whitson. I'm a particle for exist and I'm 13 00:01:01,120 --> 00:01:04,560 Speaker 1: desperately seeking dark matter. Sounds like a movie from the eighties, 14 00:01:05,080 --> 00:01:07,880 Speaker 1: Desperately seeking dark Matter. I hope it is, because in 15 00:01:07,959 --> 00:01:10,000 Speaker 1: the end of those movies, they always find what they're 16 00:01:10,040 --> 00:01:13,000 Speaker 1: looking for. So that means that in about two hours, 17 00:01:13,040 --> 00:01:16,000 Speaker 1: I'll discover dark matter. There'll be some ups and downs, 18 00:01:16,080 --> 00:01:18,440 Speaker 1: but in those movies they don't always find what they 19 00:01:18,440 --> 00:01:21,360 Speaker 1: were expecting. That's true. Sometimes it turns out the friends 20 00:01:21,360 --> 00:01:26,840 Speaker 1: they made along the way are the real dark matter. Anyways, 21 00:01:26,920 --> 00:01:29,959 Speaker 1: Welcome to our podcast, Daniel and Jorge Explain the Universe, 22 00:01:30,120 --> 00:01:32,440 Speaker 1: a production of My Heart Radio, in which we take 23 00:01:32,480 --> 00:01:35,840 Speaker 1: you on a wrong calm journey throughout the entire universe, 24 00:01:36,160 --> 00:01:38,840 Speaker 1: hoping you'll fall in love with the biggest mysteries and 25 00:01:38,880 --> 00:01:41,800 Speaker 1: the smallest mysteries, the craziest things that are out there. 26 00:01:41,959 --> 00:01:45,399 Speaker 1: Because the curiosity of scientists is your curiosity. The things 27 00:01:45,440 --> 00:01:48,240 Speaker 1: you wonder about are the things that scientists today are 28 00:01:48,280 --> 00:01:51,320 Speaker 1: still trying to understand. Yeah, and sometimes we cover not 29 00:01:51,440 --> 00:01:55,120 Speaker 1: just the science itself, but when scientists discover something new 30 00:01:55,240 --> 00:01:57,240 Speaker 1: and how they went about doing it. That's right in. 31 00:01:57,320 --> 00:02:00,360 Speaker 1: My favorite version of these stories is when somebody build 32 00:02:00,440 --> 00:02:03,120 Speaker 1: something new to look for something a and then they 33 00:02:03,120 --> 00:02:07,040 Speaker 1: accidentally stumble across something totally different, which blows their minds 34 00:02:07,240 --> 00:02:10,400 Speaker 1: and changes our understanding of the universe. Those are my 35 00:02:10,440 --> 00:02:12,480 Speaker 1: favorite stories. That happens a lot, like you're looking for 36 00:02:12,520 --> 00:02:15,200 Speaker 1: one thing, but you discover something else. That happens almost 37 00:02:15,280 --> 00:02:18,320 Speaker 1: every time we turn on a new kind of eyeball 38 00:02:18,400 --> 00:02:22,000 Speaker 1: to the universe. Universe is so filled with surprises that 39 00:02:22,040 --> 00:02:24,840 Speaker 1: every time we create a new technology that lets us 40 00:02:25,080 --> 00:02:27,160 Speaker 1: listen to the universe or look at the universe in 41 00:02:27,160 --> 00:02:30,160 Speaker 1: a new way, we see something weird. You know, you've 42 00:02:30,160 --> 00:02:34,800 Speaker 1: got the cosmic microwave background radiation, this small hiss of 43 00:02:34,840 --> 00:02:38,320 Speaker 1: background noise that filled the antenna in New Jersey that 44 00:02:38,400 --> 00:02:41,160 Speaker 1: those guys were definitely not looking for, but ended up 45 00:02:41,200 --> 00:02:44,440 Speaker 1: being pretty good evidence for the Big Bang. You've got 46 00:02:44,480 --> 00:02:47,840 Speaker 1: particles discovered here and there when nobody was expecting them. 47 00:02:47,880 --> 00:02:50,000 Speaker 1: Every time we turn on a new telescope, we see 48 00:02:50,000 --> 00:02:52,600 Speaker 1: some new kind of star or galaxy or black hole 49 00:02:52,720 --> 00:02:54,960 Speaker 1: or weird stuff that we didn't expect. Right, it's a 50 00:02:54,960 --> 00:02:58,040 Speaker 1: wonderful experience. And what's the standard protocol? Do you, like, 51 00:02:58,360 --> 00:03:00,520 Speaker 1: pretend you weren't looking for a and you are looking 52 00:03:00,520 --> 00:03:02,520 Speaker 1: for being out the whole time, or do you pretend 53 00:03:02,560 --> 00:03:05,320 Speaker 1: that it was all part of the you know, master plan. No, 54 00:03:05,480 --> 00:03:09,200 Speaker 1: it's the best kind of discovery, the unanticipated discovery. As 55 00:03:09,240 --> 00:03:12,200 Speaker 1: an experimentalist, you're not interested in going to find what 56 00:03:12,320 --> 00:03:15,520 Speaker 1: somebody else predicted because then hey, they get the Nobel Prize. 57 00:03:15,520 --> 00:03:17,800 Speaker 1: It was really their idea. You're just checking the box. 58 00:03:18,200 --> 00:03:20,639 Speaker 1: You're an experimentalist if you want to be an explorer, 59 00:03:20,720 --> 00:03:22,640 Speaker 1: if you want to go out in the universe and 60 00:03:22,720 --> 00:03:25,600 Speaker 1: discover something new, and so yeah, you're gonna, you know, 61 00:03:25,639 --> 00:03:28,520 Speaker 1: follow the map and get ideas from the theorists. But 62 00:03:28,560 --> 00:03:31,400 Speaker 1: the fantasy is to find something weird, something new, which 63 00:03:31,480 --> 00:03:35,920 Speaker 1: changes are very understanding of the universe, and so frankly, 64 00:03:35,960 --> 00:03:38,680 Speaker 1: there's a bit of sometimes an overreaction like, hey, I 65 00:03:38,680 --> 00:03:42,080 Speaker 1: found something I don't understand. Maybe it's a crazy new discovery. Yeah, 66 00:03:42,080 --> 00:03:44,640 Speaker 1: I'm sure mcgillan and lucent Clark and all those explorers 67 00:03:44,640 --> 00:03:47,920 Speaker 1: would often say, whoops, what's this? Maybe it's dark matter 68 00:03:49,800 --> 00:03:52,320 Speaker 1: in the anachronistic science fiction time travel movie that I'm 69 00:03:52,360 --> 00:03:55,520 Speaker 1: pitching Netflix. That's totally a scene. Is it a romantic 70 00:03:55,520 --> 00:03:58,320 Speaker 1: comedy as well? Of course everything has to be a 71 00:03:58,360 --> 00:04:03,800 Speaker 1: wrong comedy days. That's right, it's a Marvel formula, that's right, 72 00:04:04,000 --> 00:04:06,840 Speaker 1: dark matters of dark matter. But anyway, we're talking today 73 00:04:06,840 --> 00:04:10,680 Speaker 1: about one such experiment that was looking for one thing 74 00:04:10,720 --> 00:04:15,520 Speaker 1: and may have accidentally or inadvertently found something else, maybe 75 00:04:15,880 --> 00:04:19,120 Speaker 1: of more importance. That's right. This is an experiment that 76 00:04:19,200 --> 00:04:21,600 Speaker 1: released their results a few weeks ago, and we got 77 00:04:21,720 --> 00:04:24,800 Speaker 1: questions from listeners about what does this mean? And it's 78 00:04:24,839 --> 00:04:27,880 Speaker 1: also made a real buzz in the particle physics community. 79 00:04:28,080 --> 00:04:32,000 Speaker 1: Here's examples of what some prominent particle physicists said. Neil Weiner, 80 00:04:32,080 --> 00:04:34,360 Speaker 1: a dark matter of physicist at n y U, said, 81 00:04:34,720 --> 00:04:36,920 Speaker 1: I'm trying to be calm here, but it's hard not 82 00:04:36,960 --> 00:04:39,760 Speaker 1: to be hyperbolic. If this is real, calling it a 83 00:04:39,800 --> 00:04:44,000 Speaker 1: game changer would be an understatement. Yeah, so people got 84 00:04:44,000 --> 00:04:46,840 Speaker 1: pretty excited about this, and then that is pretty hyperbolic. 85 00:04:47,920 --> 00:04:51,120 Speaker 1: Mike Turner, famous physicist at U Chicago former head of 86 00:04:51,160 --> 00:04:54,120 Speaker 1: the NSF, said quote, I really want to believe it, 87 00:04:54,160 --> 00:04:57,520 Speaker 1: but I think it will probably break my heart. Just 88 00:04:57,560 --> 00:05:00,719 Speaker 1: like a good romantic comedy. It's X you in it 89 00:05:00,760 --> 00:05:02,880 Speaker 1: makes you fall in love with it, and then it crushes. 90 00:05:04,720 --> 00:05:06,760 Speaker 1: So there's a lot of buzz about this. Huh. People 91 00:05:06,760 --> 00:05:10,599 Speaker 1: are tentatively excited. People are tendively excited. They want this 92 00:05:10,720 --> 00:05:14,279 Speaker 1: to be something new, something fantastic, something fundamental. On the 93 00:05:14,320 --> 00:05:17,040 Speaker 1: other hand, of course, it could just be nothing. It 94 00:05:17,120 --> 00:05:19,960 Speaker 1: could be the experiment list don't quite understand what their 95 00:05:20,000 --> 00:05:23,680 Speaker 1: machine is doing. So all these professional, prominent particle physics 96 00:05:23,680 --> 00:05:29,120 Speaker 1: professors are pausing their expectations. Well, you know, they are 97 00:05:29,160 --> 00:05:33,039 Speaker 1: pretty particular about claiming discovery, so you have to you 98 00:05:33,080 --> 00:05:35,720 Speaker 1: have to really cross the threshold before people believe you've 99 00:05:35,720 --> 00:05:38,320 Speaker 1: found something new. All right, so Tody on the podcast, 100 00:05:38,400 --> 00:05:46,600 Speaker 1: we'll be asking the question, did the Zenon Experiment just 101 00:05:46,800 --> 00:05:50,000 Speaker 1: discover an axion? Now that's a lot of x is 102 00:05:50,040 --> 00:05:52,200 Speaker 1: in for one sentence. There's a lot of xs and 103 00:05:52,200 --> 00:05:56,200 Speaker 1: a lot of non axion. Those are two words which 104 00:05:56,640 --> 00:05:58,919 Speaker 1: sounds sound pretty sign See, you know, the X just 105 00:05:59,000 --> 00:06:01,440 Speaker 1: kind of pushes a over that's right, you know. And 106 00:06:01,480 --> 00:06:04,239 Speaker 1: the Xon experiment is pretty cool. It's actually well named 107 00:06:04,279 --> 00:06:07,680 Speaker 1: because basically it's a huge tub of zenon and it's 108 00:06:07,720 --> 00:06:11,080 Speaker 1: sitting in a mine underground in Italy looking for dark matter, 109 00:06:11,560 --> 00:06:14,359 Speaker 1: and everybody's been waiting to hear what it says, like 110 00:06:14,440 --> 00:06:17,560 Speaker 1: will it find dark matter? And so it was already 111 00:06:17,600 --> 00:06:20,400 Speaker 1: an exciting moment for particle physics when we knew they 112 00:06:20,440 --> 00:06:23,599 Speaker 1: were going to announce their results, and so everybody was 113 00:06:23,600 --> 00:06:26,480 Speaker 1: pretty surprised at what they ended up announcing. But anyways, 114 00:06:26,480 --> 00:06:30,480 Speaker 1: we were wondering, as always, how much of this incredible 115 00:06:30,520 --> 00:06:33,400 Speaker 1: potential discovery had made it out there to the public. 116 00:06:33,760 --> 00:06:37,120 Speaker 1: Aware people are about this question, and so Daniel, as 117 00:06:37,200 --> 00:06:39,359 Speaker 1: usually went out there into the wild with the Internet 118 00:06:39,440 --> 00:06:42,640 Speaker 1: to get people's reactions to the question, did the Zenon 119 00:06:42,760 --> 00:06:46,440 Speaker 1: Experiment just discover an axio? That's right, and if you're 120 00:06:46,520 --> 00:06:49,960 Speaker 1: interested in participating in our virtual person on the street 121 00:06:49,960 --> 00:06:53,840 Speaker 1: interviews and lending your speculation to our podcast, please write 122 00:06:53,839 --> 00:06:56,520 Speaker 1: to us two questions at Daniel and Jorge dot com. 123 00:06:56,800 --> 00:06:59,720 Speaker 1: We're always looking for and welcoming volunteers. Think about it, 124 00:06:59,760 --> 00:07:02,520 Speaker 1: ourse A, Can do the words Zenon and Axion mean 125 00:07:02,560 --> 00:07:06,000 Speaker 1: anything to you? If someone ask you this question, Here's 126 00:07:06,000 --> 00:07:08,320 Speaker 1: what people had to say. I have no idea what 127 00:07:08,680 --> 00:07:12,800 Speaker 1: an actually, honest, but I do know that Xenon experiment 128 00:07:12,880 --> 00:07:15,760 Speaker 1: has to do something with finding dark matter. I have 129 00:07:16,080 --> 00:07:19,320 Speaker 1: no idea what the Zenon experiment is. I have no 130 00:07:19,400 --> 00:07:22,960 Speaker 1: idea what actions are. Just listen to that fascinating episode 131 00:07:22,960 --> 00:07:26,880 Speaker 1: this week. However, I have not heard about this one either. 132 00:07:27,040 --> 00:07:30,600 Speaker 1: I'm not entirely sure, but I don't think so. The 133 00:07:30,640 --> 00:07:33,560 Speaker 1: word Zenon just reminds me of zena warrior princess, so 134 00:07:33,680 --> 00:07:35,960 Speaker 1: I have no idea what that is. Honestly, I thought 135 00:07:36,040 --> 00:07:39,880 Speaker 1: until we're just making computer hardware, not physics experiments. But 136 00:07:40,320 --> 00:07:42,560 Speaker 1: what do I know? Maybe the third new scene on 137 00:07:42,680 --> 00:07:46,240 Speaker 1: CPUs have somehow discovered a deep truth of the universe. 138 00:07:46,480 --> 00:07:48,640 Speaker 1: I have no idea of what either of them is. 139 00:07:49,040 --> 00:07:52,720 Speaker 1: But whenever we hear statements in science with a question 140 00:07:52,760 --> 00:07:56,240 Speaker 1: mark in the end, then the answer is most likely no. 141 00:07:56,480 --> 00:07:58,440 Speaker 1: All right, I'm with the person who said it sounds 142 00:07:58,440 --> 00:08:01,640 Speaker 1: like Zena the Warrior Princess. I bet she made a 143 00:08:01,680 --> 00:08:04,080 Speaker 1: lot of discoveries in her time. You know, she was 144 00:08:04,120 --> 00:08:07,400 Speaker 1: an explorer for sure, and a trailblazer. How to slice 145 00:08:07,400 --> 00:08:10,240 Speaker 1: the person in half in one swoop. I think she 146 00:08:10,400 --> 00:08:12,880 Speaker 1: destroyed the dark crystal at some point in maybe in 147 00:08:12,880 --> 00:08:15,520 Speaker 1: one episode. I think you're crossing your universes. There is 148 00:08:15,520 --> 00:08:18,600 Speaker 1: there a dark crystal, and well, I was a little 149 00:08:18,640 --> 00:08:21,160 Speaker 1: surprised that none of our listeners had heard of this 150 00:08:21,360 --> 00:08:23,680 Speaker 1: result in science, because it was on the New York 151 00:08:23,720 --> 00:08:26,640 Speaker 1: Times and all sorts websites, and definitely a few listeners 152 00:08:26,640 --> 00:08:29,120 Speaker 1: wrote in to ask us. But I guess it hadn't 153 00:08:29,160 --> 00:08:32,280 Speaker 1: penetrated as deeply as I thought. So this maybe the 154 00:08:32,360 --> 00:08:35,440 Speaker 1: first time you're hearing about this fascinating result, in which 155 00:08:35,440 --> 00:08:38,320 Speaker 1: case I'm glad that we get to explain it to you. Yeah, 156 00:08:38,520 --> 00:08:40,480 Speaker 1: was it like front pages of New York Times or 157 00:08:40,840 --> 00:08:42,680 Speaker 1: you know, there's kind of a lot going on these days. 158 00:08:43,320 --> 00:08:45,360 Speaker 1: There is a lot going on these days. I don't 159 00:08:45,400 --> 00:08:47,400 Speaker 1: get the New York Times physical copies, so I can't 160 00:08:47,400 --> 00:08:50,320 Speaker 1: really tell how prominently it is. And I definitely dig 161 00:08:50,400 --> 00:08:53,840 Speaker 1: down to read the science underneath all the crazy politics 162 00:08:53,840 --> 00:08:56,720 Speaker 1: and medical pandemic news, just to sort of escape that 163 00:08:56,760 --> 00:09:00,680 Speaker 1: crazy university, just to kind of sorbe or your pellette 164 00:09:00,720 --> 00:09:04,400 Speaker 1: a little bit. Also, it's your profession, and I'm curious 165 00:09:04,400 --> 00:09:05,840 Speaker 1: and I'm hoping that they will discover it. And I 166 00:09:05,840 --> 00:09:09,400 Speaker 1: heard about it professionally. Also, you know through particle physicists 167 00:09:09,440 --> 00:09:12,280 Speaker 1: that something exciting was coming, and so I was waiting 168 00:09:12,320 --> 00:09:14,240 Speaker 1: to hear about this result. And by that you mean Twitter. 169 00:09:14,800 --> 00:09:16,480 Speaker 1: You heard it on Twitter. I'm not going to give 170 00:09:16,520 --> 00:09:22,400 Speaker 1: away are totally secret mechanisms for communicating important important scientific 171 00:09:22,440 --> 00:09:29,040 Speaker 1: advance scientific it probably is secret because nobody's following you. 172 00:09:30,760 --> 00:09:33,840 Speaker 1: Just kidding, all right, So let's get dig into it. So, Daniel, 173 00:09:34,200 --> 00:09:39,360 Speaker 1: potentially amazing and groundbreaking and world turning result has just 174 00:09:39,400 --> 00:09:42,680 Speaker 1: been found in an experiment in this world recently a 175 00:09:42,679 --> 00:09:45,080 Speaker 1: few weeks ago. So step us through it. What is 176 00:09:45,160 --> 00:09:48,199 Speaker 1: the Zenon experiment? First of all, so the Zenon experiment 177 00:09:48,600 --> 00:09:53,920 Speaker 1: is basically a huge tub of zenon, cooled down, sitting underground. 178 00:09:54,360 --> 00:09:56,200 Speaker 1: And you might wonder, like, why would you want to 179 00:09:56,200 --> 00:09:58,280 Speaker 1: do that. Who would want to chill a bunch of 180 00:09:58,400 --> 00:10:01,840 Speaker 1: zenon down to very cold temperatures? And the reason is 181 00:10:01,880 --> 00:10:05,200 Speaker 1: that it's looking for a very shy particle. It's hoping 182 00:10:05,240 --> 00:10:08,560 Speaker 1: to spot one particle of dark matter flying through the 183 00:10:08,559 --> 00:10:12,280 Speaker 1: Earth and banging into one of these zenon atoms. Interesting, 184 00:10:12,360 --> 00:10:14,760 Speaker 1: so it's a paint a picture for us. How big 185 00:10:14,760 --> 00:10:16,400 Speaker 1: of a tub are we talking about? Is it like 186 00:10:16,440 --> 00:10:18,959 Speaker 1: a pool or is it like a bathtub or is 187 00:10:19,000 --> 00:10:22,120 Speaker 1: it more like a bucket. It's like a really big bucket, 188 00:10:22,600 --> 00:10:24,920 Speaker 1: maybe like a hot tub size. I mean, xenon is 189 00:10:24,960 --> 00:10:28,679 Speaker 1: pretty heavy stuff. Is this is about three metric tons 190 00:10:28,720 --> 00:10:31,679 Speaker 1: of zenon and so you know it's about as tall 191 00:10:31,760 --> 00:10:35,280 Speaker 1: as a person and maybe a meter in diameter, and 192 00:10:35,360 --> 00:10:38,280 Speaker 1: so you know it's enough to like flash freeze Han Solo. 193 00:10:38,400 --> 00:10:42,520 Speaker 1: Probably now we're talking language, I can understand any And 194 00:10:42,600 --> 00:10:44,360 Speaker 1: that was definitely a wrong com. I mean, if Star 195 00:10:44,360 --> 00:10:46,240 Speaker 1: Wars is not a wrong com, I don't know what is. 196 00:10:46,320 --> 00:10:50,719 Speaker 1: I know exactly exactly. Anyway, this Xenion experiment was not 197 00:10:50,840 --> 00:10:54,760 Speaker 1: trying to you know, capture and freeze people who are 198 00:10:54,800 --> 00:10:57,960 Speaker 1: on the run from interstellar bounty hunters. Instead, it was 199 00:10:57,960 --> 00:11:00,920 Speaker 1: trying to capture a signal of dark matter, this stuff 200 00:11:00,960 --> 00:11:04,239 Speaker 1: that fills the universe, but so far has been frustratingly 201 00:11:04,360 --> 00:11:07,559 Speaker 1: invisible to us. Let's see and why zenon. Xenon is 202 00:11:07,600 --> 00:11:10,040 Speaker 1: one of the noble gases, right, that's right, it's one 203 00:11:10,080 --> 00:11:12,600 Speaker 1: of the noble gases. And we use xenon because if 204 00:11:12,720 --> 00:11:14,800 Speaker 1: dark matter bumps into something, it's going to be a 205 00:11:14,880 --> 00:11:17,360 Speaker 1: very small signal. And so what we want is a 206 00:11:17,520 --> 00:11:21,440 Speaker 1: very big pile of very quiet matter that otherwise isn't 207 00:11:21,440 --> 00:11:23,960 Speaker 1: doing anything, so that if we get a little signal 208 00:11:23,960 --> 00:11:26,319 Speaker 1: of dark matter comes in and happens to bump into 209 00:11:26,360 --> 00:11:28,760 Speaker 1: one of these nuclei, we can tell if you just 210 00:11:28,800 --> 00:11:31,520 Speaker 1: got like a huge tub of hydrogen as all sorts 211 00:11:31,520 --> 00:11:33,679 Speaker 1: of crazy stuff going on all the time, and if 212 00:11:33,760 --> 00:11:35,839 Speaker 1: dark matter comes in and bumps the hydrogen atom, you 213 00:11:35,840 --> 00:11:38,439 Speaker 1: wouldn't even notice. But a big pool of xenon and 214 00:11:38,559 --> 00:11:42,160 Speaker 1: just sitting there mostly does nothing. And so something is 215 00:11:42,200 --> 00:11:45,679 Speaker 1: able to penetrate a mile underground and bump into one 216 00:11:45,679 --> 00:11:49,280 Speaker 1: of these xenon atoms, then you might notice it's pretty chill. 217 00:11:49,440 --> 00:11:52,400 Speaker 1: It doesn't, I guess it's it's cold, so it's not moving, 218 00:11:52,440 --> 00:11:54,760 Speaker 1: and it's also not very reactive. I guess that's what 219 00:11:54,800 --> 00:11:57,439 Speaker 1: you're saying exactly, And that's why we use these noble gasses. 220 00:11:57,720 --> 00:12:00,400 Speaker 1: Other teams were thinking about using liquid are Gone, for example, 221 00:12:00,559 --> 00:12:03,559 Speaker 1: But Zeno really has the best combination of being available, 222 00:12:03,760 --> 00:12:06,600 Speaker 1: not being crazy expensive, and giving off the right kind 223 00:12:06,600 --> 00:12:09,320 Speaker 1: of signal when it does get bumped, and it also 224 00:12:09,320 --> 00:12:13,439 Speaker 1: fit the acronym better exactly. And that's how we make 225 00:12:13,440 --> 00:12:15,400 Speaker 1: these choices. Really. In the end, it's it's about the 226 00:12:15,720 --> 00:12:18,520 Speaker 1: r It would have been awkward if the Zenon experiment 227 00:12:18,640 --> 00:12:20,840 Speaker 1: use our gun when it is maybe nobody who had 228 00:12:20,880 --> 00:12:22,560 Speaker 1: to know. It could be a big cover up. You know, 229 00:12:22,600 --> 00:12:26,400 Speaker 1: this is Xenon gait. It's all covered up anyways. Yeah, 230 00:12:26,440 --> 00:12:28,800 Speaker 1: And you know, we build this device because we're looking 231 00:12:28,880 --> 00:12:31,800 Speaker 1: for a particular thing. We know that dark matters out there. 232 00:12:32,200 --> 00:12:34,880 Speaker 1: We know that it has its matter that has gravity, 233 00:12:34,880 --> 00:12:37,400 Speaker 1: that's some kind of stuff, but we don't really know 234 00:12:37,520 --> 00:12:40,760 Speaker 1: very much else about it. We hope that it also 235 00:12:40,840 --> 00:12:42,679 Speaker 1: can do something else, That is, that it can bump 236 00:12:42,679 --> 00:12:45,840 Speaker 1: into normal matter and sometimes interact with it. We're using 237 00:12:45,960 --> 00:12:48,680 Speaker 1: some sort of force that's not grab We know dark 238 00:12:48,720 --> 00:12:51,520 Speaker 1: matter doesn't feel electromagnetism, so it can't be that force. 239 00:12:51,679 --> 00:12:53,960 Speaker 1: We know it doesn't feel the strong force. We know 240 00:12:54,000 --> 00:12:56,160 Speaker 1: it doesn't feel a weak force. If it felt one 241 00:12:56,160 --> 00:12:58,600 Speaker 1: of those forces, we would have seen it already. So 242 00:12:58,800 --> 00:13:01,920 Speaker 1: we're hoping, beyond hope that it also has some new 243 00:13:02,000 --> 00:13:04,320 Speaker 1: kind of dark force and it can use that to 244 00:13:04,360 --> 00:13:07,840 Speaker 1: bump into normal matter. Interesting, and we don't know that 245 00:13:07,880 --> 00:13:09,640 Speaker 1: it does. It's just a guess. It's just a hope. 246 00:13:09,679 --> 00:13:11,560 Speaker 1: It's like, well, if it is this thing and it 247 00:13:11,600 --> 00:13:13,760 Speaker 1: has this new force, then maybe we could see it 248 00:13:13,800 --> 00:13:17,200 Speaker 1: this way. So Zenon, this experiment really is built on 249 00:13:17,440 --> 00:13:19,800 Speaker 1: sort of a lot of assumptions, like let's build the 250 00:13:19,880 --> 00:13:22,320 Speaker 1: kind of thing that could see this very particular kind 251 00:13:22,320 --> 00:13:24,360 Speaker 1: of particle. You could be wrong, like it could be 252 00:13:24,400 --> 00:13:28,360 Speaker 1: that maybe dark matter only interacts through gravity, in which 253 00:13:28,400 --> 00:13:31,720 Speaker 1: case even this giant tub of Xenon wouldn't see it, 254 00:13:31,840 --> 00:13:34,040 Speaker 1: or interact with it or catch it exactly. We have 255 00:13:34,120 --> 00:13:37,280 Speaker 1: only very weak arguments to suggest that dark matter is 256 00:13:37,320 --> 00:13:40,240 Speaker 1: a particle and that it can interact with normal matter 257 00:13:40,280 --> 00:13:42,720 Speaker 1: in any way other than gravity. We've never seen it. 258 00:13:42,840 --> 00:13:46,160 Speaker 1: We've certainly I've never proven that it can interact non gravitationally. 259 00:13:46,280 --> 00:13:48,880 Speaker 1: We're just sort of hoping it does, because if it doesn't, 260 00:13:48,920 --> 00:13:51,839 Speaker 1: we have no chance at ever figuring out what kind 261 00:13:51,840 --> 00:13:54,920 Speaker 1: of particle it is, because gravity is so weak that 262 00:13:55,000 --> 00:13:58,040 Speaker 1: you can only use it to study like enormous galaxy 263 00:13:58,120 --> 00:14:01,120 Speaker 1: sized blobs of dark matter. So we're hoping it's there, 264 00:14:01,600 --> 00:14:03,800 Speaker 1: and you know, in particle physics we often play the 265 00:14:03,840 --> 00:14:06,720 Speaker 1: game of finding a negative result, Like if we build 266 00:14:06,760 --> 00:14:09,319 Speaker 1: this thing and we don't see it, that means, hey, 267 00:14:09,440 --> 00:14:11,440 Speaker 1: if dark matter is a particle it doesn't have this 268 00:14:11,520 --> 00:14:14,000 Speaker 1: kind of interaction, we can still learn something about what 269 00:14:14,080 --> 00:14:17,319 Speaker 1: dark matter doesn't do. It's not nearly as exciting, but 270 00:14:17,520 --> 00:14:20,200 Speaker 1: you know, it's still new territory scientific You're still checking 271 00:14:20,240 --> 00:14:23,360 Speaker 1: a box and hoping to get a clearer picture. Yeah, exactly. 272 00:14:23,640 --> 00:14:25,880 Speaker 1: But you know, sometimes you build this device to look 273 00:14:25,920 --> 00:14:29,280 Speaker 1: for one very particular kind of particle and it spots 274 00:14:29,320 --> 00:14:32,360 Speaker 1: something else. You know, in some sense, it's very specific. 275 00:14:32,400 --> 00:14:34,880 Speaker 1: It's looking for this kind of particle, a whimp, a 276 00:14:34,920 --> 00:14:38,280 Speaker 1: weekly interacting massive particle that we think dark matter might be. 277 00:14:38,760 --> 00:14:41,040 Speaker 1: But on the other hand, it's just a very sensitive, 278 00:14:41,160 --> 00:14:44,920 Speaker 1: very quiet detector that could notice some other weird new 279 00:14:45,000 --> 00:14:46,920 Speaker 1: thing flying through the game. So it's kind of a 280 00:14:47,000 --> 00:14:50,840 Speaker 1: last attempt at trying to feel or touch dark matter. 281 00:14:50,920 --> 00:14:53,200 Speaker 1: Because if it doesn't work, then it tells you that 282 00:14:53,320 --> 00:14:56,080 Speaker 1: maybe we'll never interact with dark matter. Yeah, and this 283 00:14:56,120 --> 00:14:59,320 Speaker 1: is sort of the like seventh step in the succession 284 00:14:59,600 --> 00:15:02,400 Speaker 1: of the detectors. They started with a very small little 285 00:15:02,440 --> 00:15:05,000 Speaker 1: container of zenon just to see if it worked, and 286 00:15:05,080 --> 00:15:07,360 Speaker 1: it did, but the smaller amount of zeno and you have, 287 00:15:07,480 --> 00:15:09,800 Speaker 1: the less sensitive you are. So then they scaled up, 288 00:15:09,920 --> 00:15:11,800 Speaker 1: and they scaled up and they scaled up, and this 289 00:15:11,880 --> 00:15:13,800 Speaker 1: is the first time they've had a detector that's like 290 00:15:14,120 --> 00:15:16,960 Speaker 1: more than a ton of zenon. And as they were 291 00:15:17,040 --> 00:15:20,880 Speaker 1: running this one, their simultaneously building a bigger one. And 292 00:15:20,960 --> 00:15:22,880 Speaker 1: the reason is that you want to run longer and 293 00:15:22,920 --> 00:15:25,720 Speaker 1: you want more zenon because that gives you more chances 294 00:15:25,800 --> 00:15:29,360 Speaker 1: to find it. So this is like xenon x L, 295 00:15:30,280 --> 00:15:33,240 Speaker 1: and now they're thinking about zenon x x L. Yeah, 296 00:15:33,600 --> 00:15:36,480 Speaker 1: this is xenon one ton, and pretty soon they're coming 297 00:15:36,480 --> 00:15:40,320 Speaker 1: with zenon n ton, which means like several tons of zeno. 298 00:15:40,800 --> 00:15:43,160 Speaker 1: And then there's competition. There's one in the US called 299 00:15:43,280 --> 00:15:45,960 Speaker 1: l Z and another one in China called Panda X, 300 00:15:46,200 --> 00:15:49,240 Speaker 1: and everybody's racing to build the biggest amount of zenon 301 00:15:49,640 --> 00:15:53,480 Speaker 1: and who has the coolest name for their device definitely 302 00:15:53,520 --> 00:15:55,800 Speaker 1: panneda x wins that one. All right. So the idea 303 00:15:55,840 --> 00:15:58,000 Speaker 1: is that you have this tub of zenon. It's chill, 304 00:15:58,240 --> 00:16:01,640 Speaker 1: it's not very reactive. And the scenarios and maybe a 305 00:16:01,680 --> 00:16:04,480 Speaker 1: dark matter particle will come in and bump into a 306 00:16:04,600 --> 00:16:08,040 Speaker 1: xenon atom and then what like move it or cause 307 00:16:08,120 --> 00:16:11,720 Speaker 1: it to flash or wiggle? What's the what's the scenario 308 00:16:11,800 --> 00:16:14,240 Speaker 1: under which you might detect dark matter? Yes, so we're 309 00:16:14,280 --> 00:16:16,800 Speaker 1: not terribly sensitive to it. All we can see is 310 00:16:16,960 --> 00:16:20,160 Speaker 1: depositions of energy, Like a particle comes in and bumps 311 00:16:20,160 --> 00:16:22,440 Speaker 1: the xenon. We can't see the particle that came in 312 00:16:22,560 --> 00:16:25,960 Speaker 1: at all. All we can see is that the nucleus recoiled, 313 00:16:25,960 --> 00:16:28,440 Speaker 1: like the xenon got pushed a little bit, and as 314 00:16:28,440 --> 00:16:31,200 Speaker 1: you said, it deposits some energy. And what it makes 315 00:16:31,480 --> 00:16:34,120 Speaker 1: is that the xenon absorbs that energy from the little 316 00:16:34,160 --> 00:16:36,120 Speaker 1: push and then it gives it off again. It doesn't 317 00:16:36,120 --> 00:16:38,280 Speaker 1: like to hold onto it, so it usually gives off 318 00:16:38,320 --> 00:16:40,800 Speaker 1: a little photon, gives off a little flash of light. 319 00:16:41,240 --> 00:16:43,160 Speaker 1: And so this is one reason why we choose zen on. 320 00:16:43,240 --> 00:16:47,160 Speaker 1: It has really nice scintillation profits. Basically, you excite any 321 00:16:47,200 --> 00:16:50,920 Speaker 1: of the zenon atoms and they form a little molecule 322 00:16:51,160 --> 00:16:54,520 Speaker 1: pairs of zenons. Those are excited like wiggling back and forth, 323 00:16:54,680 --> 00:16:57,360 Speaker 1: and then they relax back down to two individual xenon 324 00:16:57,480 --> 00:17:00,000 Speaker 1: atoms and give off a photon, and then you can 325 00:17:00,080 --> 00:17:03,760 Speaker 1: capture those tiny, little dark flashes of light with foot 326 00:17:03,760 --> 00:17:09,480 Speaker 1: a multiplier. Interesting, very scintillating for sure, and tantalizing. I 327 00:17:09,480 --> 00:17:12,280 Speaker 1: mean basically, you have like a bathtub under a mile 328 00:17:12,440 --> 00:17:14,800 Speaker 1: underground in the dark, with a camera attached to it, 329 00:17:14,840 --> 00:17:17,120 Speaker 1: and you're waiting for little flashes of light, which could 330 00:17:17,119 --> 00:17:21,240 Speaker 1: mean ironically dark matter exactly. You could be shedding light 331 00:17:21,280 --> 00:17:23,199 Speaker 1: on dark matter. All right, Well that's what it was 332 00:17:23,320 --> 00:17:26,359 Speaker 1: built for. But recently they announced that they saw something 333 00:17:26,640 --> 00:17:30,639 Speaker 1: else and maybe even more interesting than dark matter. So 334 00:17:30,720 --> 00:17:33,000 Speaker 1: let's get into that. But first let's take a quick break. 335 00:17:45,280 --> 00:17:47,800 Speaker 1: All right. I know we're talking about this Zenon experiment 336 00:17:48,720 --> 00:17:51,600 Speaker 1: that was built to detect dark matter. So it's a 337 00:17:51,640 --> 00:17:55,679 Speaker 1: giant tub of zenon. It's sitting there, chilling, waiting for 338 00:17:55,760 --> 00:17:58,639 Speaker 1: dark matter. But then they saw something that maybe it 339 00:17:58,720 --> 00:18:01,360 Speaker 1: is not dark matter. Yes, So first of all, they've 340 00:18:01,359 --> 00:18:03,480 Speaker 1: been looking for dark matter for a while and not 341 00:18:03,520 --> 00:18:05,720 Speaker 1: seeing it, and other folks have been looking for dark 342 00:18:05,760 --> 00:18:08,440 Speaker 1: matter for a while and not seeing it, and people 343 00:18:08,480 --> 00:18:10,560 Speaker 1: started to get worried, like, well, maybe it's not there, 344 00:18:10,760 --> 00:18:14,560 Speaker 1: or maybe it's different from what we expected, because these 345 00:18:14,600 --> 00:18:17,000 Speaker 1: experiments are really good at seeing dark matter if it 346 00:18:17,040 --> 00:18:20,400 Speaker 1: has a certain amount of mass, something between like ten 347 00:18:20,920 --> 00:18:24,120 Speaker 1: and you know, maybe two hundred giga electron volts, which 348 00:18:24,119 --> 00:18:27,160 Speaker 1: is about the mass of a proton. If dark matter 349 00:18:27,280 --> 00:18:29,639 Speaker 1: was much lighter than that, it might not have enough 350 00:18:29,760 --> 00:18:33,120 Speaker 1: energy to bump into the xenon atoms and excite them. 351 00:18:33,160 --> 00:18:36,240 Speaker 1: It might be there, it might be flying through your detector. 352 00:18:36,280 --> 00:18:38,479 Speaker 1: It might be bumping into the xenon atoms but not 353 00:18:38,520 --> 00:18:40,960 Speaker 1: giving them enough energy to give off that flash of light. 354 00:18:41,440 --> 00:18:43,880 Speaker 1: So people were worried about that scenario. So they pivoted 355 00:18:43,880 --> 00:18:46,280 Speaker 1: and they said, well, let's use the same detector but 356 00:18:46,359 --> 00:18:48,080 Speaker 1: trying to figure out a way to use it to 357 00:18:48,160 --> 00:18:51,560 Speaker 1: look for lighter mass dark matter. And the way they 358 00:18:51,600 --> 00:18:54,280 Speaker 1: do that is instead of looking for the xenon nucleus 359 00:18:54,280 --> 00:18:56,879 Speaker 1: the protons and neutrons, that heavy blob at the center 360 00:18:56,920 --> 00:18:59,400 Speaker 1: of the atom, they said, let's look forward bumping into 361 00:18:59,400 --> 00:19:02,160 Speaker 1: the electron, because the electron is really light, has very 362 00:19:02,240 --> 00:19:05,400 Speaker 1: very little mass. So they developed a technology to look 363 00:19:05,440 --> 00:19:09,639 Speaker 1: for electron recoils instead of nuclear recoils. So those are different. 364 00:19:09,760 --> 00:19:12,320 Speaker 1: Those are different. They give different signatures, Like if you 365 00:19:12,359 --> 00:19:15,280 Speaker 1: bump an electron off of the xenon, all of a sudden, 366 00:19:15,280 --> 00:19:18,560 Speaker 1: you have a charged particle inside this pool of xenon, 367 00:19:18,960 --> 00:19:20,960 Speaker 1: and they have an electric field which will pull that 368 00:19:21,040 --> 00:19:24,119 Speaker 1: electron out of this tub of zenon and measure it. 369 00:19:24,600 --> 00:19:28,080 Speaker 1: So they can tell that signature separately from the nuclear recoil. 370 00:19:28,080 --> 00:19:30,880 Speaker 1: Like a single electron or a single ion you can 371 00:19:30,880 --> 00:19:33,320 Speaker 1: detect that. You can detect that because it triggers a 372 00:19:33,320 --> 00:19:35,800 Speaker 1: little shower. It makes more of itself and that lets 373 00:19:35,840 --> 00:19:38,679 Speaker 1: you detect it. Actually, you know the nuclear recoil and 374 00:19:38,720 --> 00:19:42,000 Speaker 1: an electron recoil will give you scintillation light plus some 375 00:19:42,080 --> 00:19:44,679 Speaker 1: ionization from the electrons, and so it's a game of 376 00:19:44,720 --> 00:19:47,160 Speaker 1: like you know the ratios, you can tell them apart. 377 00:19:47,280 --> 00:19:49,640 Speaker 1: Is a bit technical, but they can tell an electron 378 00:19:49,680 --> 00:19:53,040 Speaker 1: recoil apart from a nuclear recoil, like are you hitting 379 00:19:53,040 --> 00:19:55,199 Speaker 1: the center of the atom or you bouncing off one 380 00:19:55,200 --> 00:19:57,840 Speaker 1: of the electrons on the side of it. Yeah, but 381 00:19:58,080 --> 00:20:01,040 Speaker 1: does that require the dark matter to be like a 382 00:20:01,119 --> 00:20:04,320 Speaker 1: certain energy? Like what if dark matter is also pretty 383 00:20:04,400 --> 00:20:07,720 Speaker 1: chill and just you know, doesn't feel like interacting with zeno. 384 00:20:07,880 --> 00:20:11,120 Speaker 1: But it's there and it could interact, but it's just chill. Yeah, well, 385 00:20:11,160 --> 00:20:13,080 Speaker 1: that's one of the issues that we already know that 386 00:20:13,160 --> 00:20:15,679 Speaker 1: dark matter is chill. We talked about this on a 387 00:20:15,680 --> 00:20:18,800 Speaker 1: podcast pretty recently. Dark matter, we know is cold, meaning 388 00:20:18,800 --> 00:20:22,159 Speaker 1: that's not moving at relativistic speeds, and so it doesn't 389 00:20:22,200 --> 00:20:23,720 Speaker 1: have a whole lot of energy, which is why it 390 00:20:23,760 --> 00:20:26,320 Speaker 1: has to be kind of massive in order to deposit 391 00:20:26,400 --> 00:20:28,640 Speaker 1: some energy. We know that it's not carrying a lot 392 00:20:28,640 --> 00:20:32,000 Speaker 1: of kinetic energy other way. But but I guess, I mean, like, 393 00:20:32,040 --> 00:20:35,040 Speaker 1: what if it's there, it's interacting with the zenon but 394 00:20:35,240 --> 00:20:38,760 Speaker 1: not at a you know, high enough energy or something. 395 00:20:38,880 --> 00:20:41,080 Speaker 1: You know, it's just like gently bumping into the zeni. 396 00:20:41,119 --> 00:20:43,520 Speaker 1: It could be. But remember that the Earth is moving 397 00:20:43,560 --> 00:20:45,960 Speaker 1: around the Sun, and so we expect to have some 398 00:20:46,119 --> 00:20:49,600 Speaker 1: velocity relative to the dark matter. Unless the dark matter 399 00:20:49,640 --> 00:20:51,919 Speaker 1: happens to also be swirling around the Sun at the 400 00:20:51,960 --> 00:20:54,639 Speaker 1: same rate, there should be basically a dark matter wind 401 00:20:54,680 --> 00:20:57,359 Speaker 1: at all times. It's not really possible to have no 402 00:20:57,520 --> 00:21:00,280 Speaker 1: velocity relative to the dark matter not hurt those words 403 00:21:00,320 --> 00:21:02,760 Speaker 1: before dark matter winds. Yeah. In fact, there's a whole 404 00:21:02,760 --> 00:21:05,600 Speaker 1: another generation of dark matter detectors. They're going to try 405 00:21:05,600 --> 00:21:08,399 Speaker 1: to look for directional dark matter, not just like is 406 00:21:08,480 --> 00:21:10,880 Speaker 1: dark matter coming in at all? But is it coming 407 00:21:10,920 --> 00:21:13,280 Speaker 1: in this direction or is it coming in that direction? 408 00:21:13,400 --> 00:21:16,080 Speaker 1: Is coming up from above or below? To try to 409 00:21:16,119 --> 00:21:18,399 Speaker 1: be a little bit more sensitive to it, like catching 410 00:21:18,440 --> 00:21:20,960 Speaker 1: the ether. Yeah, and if you do see dark matter, 411 00:21:21,200 --> 00:21:23,919 Speaker 1: you expect it to have a modulation by season, like 412 00:21:23,960 --> 00:21:25,639 Speaker 1: it should be going this way in the spring and 413 00:21:25,760 --> 00:21:28,120 Speaker 1: that way in the fall. You really are sort of 414 00:21:28,160 --> 00:21:30,760 Speaker 1: moving through a cloud of dark matter. Well, but back 415 00:21:30,800 --> 00:21:34,040 Speaker 1: to this experiment, So they gave up on trying to 416 00:21:34,160 --> 00:21:37,719 Speaker 1: detect it with the nucleus of the xenon atoms, and 417 00:21:37,760 --> 00:21:40,000 Speaker 1: so they switched to detect nague with the electrons of 418 00:21:40,000 --> 00:21:43,160 Speaker 1: the zenon atoms, and then they found something unexpected. Yeah, 419 00:21:43,200 --> 00:21:45,200 Speaker 1: and you know, give up is a bit strong. These 420 00:21:45,200 --> 00:21:47,359 Speaker 1: experiments are big, and they have different teams, so they 421 00:21:47,359 --> 00:21:50,160 Speaker 1: have sort of like a bifurcated strategy. They're still looking 422 00:21:50,200 --> 00:21:53,159 Speaker 1: for the zenon nuclear recoils, but now they added this 423 00:21:53,280 --> 00:21:55,240 Speaker 1: other way to look for a dark matter, to look 424 00:21:55,240 --> 00:21:57,639 Speaker 1: for the electron recoils, And so they look for it, 425 00:21:57,920 --> 00:21:59,840 Speaker 1: and they ran this thing for a couple of years, 426 00:22:00,040 --> 00:22:02,760 Speaker 1: been analyzing the data. And you know, it's not like 427 00:22:02,800 --> 00:22:05,280 Speaker 1: you can just see one electron recoil and be like, oh, 428 00:22:05,560 --> 00:22:08,879 Speaker 1: I found dark matter, because there are other things that 429 00:22:08,920 --> 00:22:12,040 Speaker 1: can also kick an electron. You know, like you're like 430 00:22:12,080 --> 00:22:14,840 Speaker 1: a mile underground and you're surrounded by weird minerals and 431 00:22:14,840 --> 00:22:18,040 Speaker 1: this lead and crypton and stuff down there, and sometimes 432 00:22:18,080 --> 00:22:22,040 Speaker 1: one of those atoms will decay radioactively and it will 433 00:22:22,160 --> 00:22:24,320 Speaker 1: get through your shielding and it will kick one of 434 00:22:24,320 --> 00:22:26,240 Speaker 1: your electron. So what you have to do is a 435 00:22:26,280 --> 00:22:29,000 Speaker 1: careful calculation of like how often do you expect that 436 00:22:29,080 --> 00:22:31,800 Speaker 1: to happen? And so you know, like, well, we expect 437 00:22:31,800 --> 00:22:34,639 Speaker 1: that to happen in this case two hundred and thirty 438 00:22:34,680 --> 00:22:38,199 Speaker 1: two times on average when we run this experiment, and 439 00:22:38,200 --> 00:22:39,960 Speaker 1: then you can compare that to what you see. Do 440 00:22:40,000 --> 00:22:42,359 Speaker 1: you see more than that or not I see? And 441 00:22:42,400 --> 00:22:45,280 Speaker 1: so that's what they did. They you know, I guess 442 00:22:45,320 --> 00:22:48,919 Speaker 1: they had calibrated it. They measured you know, the stuff 443 00:22:48,920 --> 00:22:51,240 Speaker 1: outside of the box and the tub, and then they 444 00:22:51,640 --> 00:22:54,119 Speaker 1: compared to what they saw inside of the tub and 445 00:22:54,160 --> 00:22:56,440 Speaker 1: that was different. Yeah, the way they calibrated is actually 446 00:22:56,480 --> 00:22:59,720 Speaker 1: they shoot radiation, they bring radioactive sources near it to 447 00:23:00,040 --> 00:23:01,600 Speaker 1: verify that they can see them, and then they move 448 00:23:01,640 --> 00:23:05,080 Speaker 1: them away to verify the signal disappears. So they can 449 00:23:05,160 --> 00:23:08,320 Speaker 1: use that to verify like how sensitive they are to 450 00:23:08,480 --> 00:23:11,159 Speaker 1: these radioactive measurements, and then they use other ways to 451 00:23:11,280 --> 00:23:14,760 Speaker 1: measure like how much lead in krypton is surrounding our experiment. 452 00:23:15,000 --> 00:23:17,480 Speaker 1: So they do a lot of work to really calibrate, 453 00:23:17,560 --> 00:23:19,400 Speaker 1: and that's the name of the game. And these experiments 454 00:23:19,400 --> 00:23:22,080 Speaker 1: where you're looking for like very small number of signals 455 00:23:22,160 --> 00:23:25,280 Speaker 1: is beating down the background, suppressing all these other things 456 00:23:25,359 --> 00:23:27,920 Speaker 1: that can look like you're dark matter, and then also 457 00:23:28,359 --> 00:23:33,040 Speaker 1: understanding them very very precisely, calibrating very very carefully, just 458 00:23:33,080 --> 00:23:35,919 Speaker 1: like with Lego and all those other very sensitive experiments. 459 00:23:36,160 --> 00:23:39,520 Speaker 1: It's all about making a very quiet experiment and understanding 460 00:23:39,520 --> 00:23:42,400 Speaker 1: how quiet it is, kind of like eliminating all the 461 00:23:42,440 --> 00:23:45,920 Speaker 1: noise or taken into account all of the noise exactly 462 00:23:45,920 --> 00:23:49,040 Speaker 1: all right. So they got more hits than they expected 463 00:23:49,040 --> 00:23:52,880 Speaker 1: of something. They saw more of these scintillations, these photon 464 00:23:53,200 --> 00:23:56,720 Speaker 1: events than they expected by a good number, that's right. 465 00:23:56,800 --> 00:24:00,000 Speaker 1: So they expected two hundred and thirty two, and they 466 00:24:00,000 --> 00:24:02,879 Speaker 1: analyzed all their data and they've got two D eighty five, 467 00:24:03,320 --> 00:24:06,959 Speaker 1: which is something like fifty more than they expected. And 468 00:24:07,160 --> 00:24:10,120 Speaker 1: they think they understand that number two thirty two pretty well, 469 00:24:10,200 --> 00:24:14,560 Speaker 1: Like they're pretty confident in that number. So it's pretty 470 00:24:14,640 --> 00:24:18,240 Speaker 1: unlikely for you know, lad in crypton to explain all 471 00:24:18,280 --> 00:24:21,199 Speaker 1: these scintillations, like it could just be random chance. I mean, 472 00:24:21,720 --> 00:24:25,040 Speaker 1: everything is quantum mechanical, and there are fluctuations, and they've 473 00:24:25,080 --> 00:24:27,920 Speaker 1: done the calculations, but the probability of this just being 474 00:24:27,960 --> 00:24:31,840 Speaker 1: like a fluctuation is like two and ten thousand. But 475 00:24:32,000 --> 00:24:34,280 Speaker 1: you know, it still seems pretty amazing to me that 476 00:24:34,440 --> 00:24:37,800 Speaker 1: it's a pretty small number. I mean, you know, twot 477 00:24:37,880 --> 00:24:42,200 Speaker 1: two data points on a massive experiment with significance about 478 00:24:42,200 --> 00:24:44,760 Speaker 1: the universe doesn't seem like a lot like I would 479 00:24:44,760 --> 00:24:47,359 Speaker 1: expect thousands or millions of data points, kind of like 480 00:24:47,440 --> 00:24:49,920 Speaker 1: you have in the article Collider. Yeah, it's a whole 481 00:24:49,920 --> 00:24:52,440 Speaker 1: different kind of world, though. Mean, they are doing their 482 00:24:52,440 --> 00:24:54,919 Speaker 1: best to make this really quiet because they expect a 483 00:24:55,040 --> 00:24:58,919 Speaker 1: very rare signal, you know, And so if you're hunting 484 00:24:58,960 --> 00:25:02,320 Speaker 1: for unicorn in the forests of Siberia, you scan a 485 00:25:02,400 --> 00:25:05,080 Speaker 1: huge forest and you try to make your filter really 486 00:25:05,160 --> 00:25:07,600 Speaker 1: really picky. So you find the unicorns. They're not just 487 00:25:07,640 --> 00:25:11,880 Speaker 1: like drowning in ordinary horses when random horns in their 488 00:25:11,920 --> 00:25:16,800 Speaker 1: foreheads exactly. But you're right, yeah, these data points are 489 00:25:16,840 --> 00:25:18,640 Speaker 1: pretty rare. I mean, they ran for a couple of years, 490 00:25:18,680 --> 00:25:21,040 Speaker 1: which means they get like one piece of data every 491 00:25:21,240 --> 00:25:24,920 Speaker 1: day or two. That's crazy. The other side of this experiment, 492 00:25:24,960 --> 00:25:28,080 Speaker 1: the nuclear recoil one, is even quieter because those events 493 00:25:28,080 --> 00:25:30,920 Speaker 1: are even harder to mimic. And I remember times when 494 00:25:30,920 --> 00:25:33,119 Speaker 1: they like they ran for two years and they saw 495 00:25:33,280 --> 00:25:36,960 Speaker 1: two events and they expected one, and they were like, oh, interesting, 496 00:25:37,080 --> 00:25:41,040 Speaker 1: what is the second event? Seriously, you know, and they 497 00:25:41,040 --> 00:25:42,960 Speaker 1: get to know they did, like this is this event 498 00:25:43,000 --> 00:25:45,879 Speaker 1: and that event. They have names and relationships with these events. 499 00:25:45,920 --> 00:25:48,920 Speaker 1: Where were you when we found the second place? Exactly? Exactly? 500 00:25:49,040 --> 00:25:50,919 Speaker 1: So this is actually kind of a big number for 501 00:25:51,000 --> 00:25:53,439 Speaker 1: a dark matter experiment. They used to dealing with events 502 00:25:53,480 --> 00:25:56,440 Speaker 1: like less than ten, but because they went over to 503 00:25:56,480 --> 00:25:59,280 Speaker 1: the electron side of things, they have larger background, so 504 00:25:59,320 --> 00:26:02,720 Speaker 1: they see more events. Okay, So I guess the idea 505 00:26:02,880 --> 00:26:06,800 Speaker 1: is they were looking for dark matter and raining for 506 00:26:06,880 --> 00:26:08,760 Speaker 1: dark matter to interact with the zene on and give 507 00:26:08,800 --> 00:26:12,360 Speaker 1: up these events and they saw more than they expected 508 00:26:12,400 --> 00:26:15,400 Speaker 1: even with dark matter, or more than they expected from 509 00:26:15,440 --> 00:26:18,680 Speaker 1: like a baseline no dark matter scenario. They saw more 510 00:26:18,720 --> 00:26:21,760 Speaker 1: than they expected from the no dark matter scenario, right. 511 00:26:22,040 --> 00:26:24,400 Speaker 1: But the signal they see is kind of weird. It's 512 00:26:24,440 --> 00:26:27,280 Speaker 1: not the signal you would expect to see from dark matter. 513 00:26:27,800 --> 00:26:31,080 Speaker 1: It piques at a very very low electron energy, like 514 00:26:31,320 --> 00:26:34,280 Speaker 1: just above where they're able to measure. That's where all 515 00:26:34,320 --> 00:26:37,360 Speaker 1: these events are piling up. Oh, I see, So that's 516 00:26:37,400 --> 00:26:39,960 Speaker 1: the mystery. That's the weird thing. It's they don't think 517 00:26:39,960 --> 00:26:42,160 Speaker 1: this is dark matter that they're seeing. This doesn't look 518 00:26:42,200 --> 00:26:45,240 Speaker 1: like dark matter. So they built this device to look 519 00:26:45,240 --> 00:26:48,119 Speaker 1: for dark matter. It's very quiet, it's very beautiful, and 520 00:26:48,160 --> 00:26:50,560 Speaker 1: they analyze the data and they see something in there 521 00:26:50,600 --> 00:26:54,439 Speaker 1: which they can't explain using normal standard model physics and 522 00:26:54,560 --> 00:26:58,000 Speaker 1: radioactive decays. But it also can't be described by dark matter. 523 00:26:58,280 --> 00:27:00,359 Speaker 1: But how do you know it's not dark matter because 524 00:27:00,400 --> 00:27:02,679 Speaker 1: we don't know what dark matter is. The signal that 525 00:27:02,760 --> 00:27:05,959 Speaker 1: they see in the Zeni experiment can't be explained by 526 00:27:06,080 --> 00:27:08,720 Speaker 1: dark matter. Whimps that they were looking for. To give 527 00:27:08,760 --> 00:27:11,520 Speaker 1: electrons a kick in the way that they see would 528 00:27:11,520 --> 00:27:15,120 Speaker 1: require a really fast moving particle, and we think dark 529 00:27:15,119 --> 00:27:17,520 Speaker 1: matter is cold. I think it's slow moving. All right, 530 00:27:17,560 --> 00:27:19,560 Speaker 1: So you're saying that they feel pretty sure that it's 531 00:27:19,640 --> 00:27:22,320 Speaker 1: not dark matter, that it just doesn't look like the 532 00:27:22,400 --> 00:27:25,000 Speaker 1: dark batter signal that they expect. I mean, they don't 533 00:27:25,000 --> 00:27:27,520 Speaker 1: have a whole lot of handles on this data. You know. 534 00:27:27,560 --> 00:27:29,399 Speaker 1: What they can do is look at the energy of 535 00:27:29,440 --> 00:27:32,679 Speaker 1: the electrons that are kicked off, and they have a 536 00:27:32,720 --> 00:27:35,480 Speaker 1: prediction for what that looks like if it's dark matter, 537 00:27:35,520 --> 00:27:36,919 Speaker 1: and they have a prediction for what that looks like 538 00:27:36,960 --> 00:27:39,760 Speaker 1: if there's no dark matter. And it doesn't agree with 539 00:27:39,800 --> 00:27:43,120 Speaker 1: either of those scenarios, Like the energy distribution they see 540 00:27:43,640 --> 00:27:46,000 Speaker 1: can't be explained by a dark matter party. Has to 541 00:27:46,000 --> 00:27:48,399 Speaker 1: be like a third scenario, something else, that's right, it 542 00:27:48,440 --> 00:27:51,120 Speaker 1: has to be something else. And so they came up 543 00:27:51,119 --> 00:27:54,920 Speaker 1: with a few crazy ideas which, if they're real, could 544 00:27:54,920 --> 00:27:58,240 Speaker 1: explain the signal and would like totally blow up physics. 545 00:27:58,400 --> 00:28:02,840 Speaker 1: What they're like, it's unicorn, essentially, they went for physics unicorn. 546 00:28:04,640 --> 00:28:06,800 Speaker 1: All right, let's get into what it could be. What 547 00:28:07,000 --> 00:28:12,200 Speaker 1: kind of new and unexpected or groundbreaking types of physics 548 00:28:12,280 --> 00:28:15,400 Speaker 1: could explain these results. But first let's take another quick break. 549 00:28:27,680 --> 00:28:31,919 Speaker 1: All right, Daniel, So the Zenon experiment did not find 550 00:28:32,119 --> 00:28:34,480 Speaker 1: dark matter as they built it, but they it found 551 00:28:34,480 --> 00:28:39,360 Speaker 1: something else. It found electron signatures at an energy level 552 00:28:39,520 --> 00:28:42,640 Speaker 1: that doesn't match with the predictions of dark matter. So 553 00:28:42,680 --> 00:28:45,160 Speaker 1: it could be something else, that's right, And so they 554 00:28:45,160 --> 00:28:48,400 Speaker 1: played around. They said, well, what is this, like, you know, 555 00:28:48,520 --> 00:28:51,120 Speaker 1: what could this be? Could it be something else? Are 556 00:28:51,120 --> 00:28:54,360 Speaker 1: there any other ideas out there, anything we weren't looking 557 00:28:54,440 --> 00:28:57,720 Speaker 1: for but might be able to explain this weird signature 558 00:28:57,840 --> 00:29:00,360 Speaker 1: that we do see. And they suggest in their paper 559 00:29:00,560 --> 00:29:03,600 Speaker 1: a few possible explanations. They have several ideas for what 560 00:29:03,640 --> 00:29:05,960 Speaker 1: this could be. They do. They have several ideas which 561 00:29:06,080 --> 00:29:12,160 Speaker 1: range from like totally crazy to super boring. I see, 562 00:29:12,200 --> 00:29:16,040 Speaker 1: from like pink unicorns to like, you know, nor walls 563 00:29:16,080 --> 00:29:18,880 Speaker 1: that's just somehow migrated to the forest. Now it's like 564 00:29:18,920 --> 00:29:22,920 Speaker 1: pink unicorns, to actually, maybe we didn't tighten the knobs 565 00:29:22,960 --> 00:29:27,240 Speaker 1: well enough. Really. Uh well, let's start with the most 566 00:29:27,240 --> 00:29:30,320 Speaker 1: boring one. The most boring is that it's not just 567 00:29:30,600 --> 00:29:33,680 Speaker 1: Zenon in the tank, like they try to make it 568 00:29:33,720 --> 00:29:36,560 Speaker 1: pure Zenon. They really work hard. There's a lot of 569 00:29:36,600 --> 00:29:40,640 Speaker 1: really smart people doing this experiment. But if if instead 570 00:29:40,680 --> 00:29:43,200 Speaker 1: of being pure zenon, it has just like a few 571 00:29:43,440 --> 00:29:47,120 Speaker 1: atoms of tritium. Treatium is an isotope of hydrogen, and 572 00:29:47,160 --> 00:29:51,080 Speaker 1: it's unstable. If you have like three atoms of tritium 573 00:29:51,080 --> 00:29:55,080 Speaker 1: per kilogram of zenon, then it can decay to helium three, 574 00:29:55,200 --> 00:29:58,960 Speaker 1: giving off an electron which looks exactly like this signature. Oh, 575 00:29:59,320 --> 00:30:02,960 Speaker 1: I see, And they not only could it be a contamination, 576 00:30:03,000 --> 00:30:06,760 Speaker 1: but they can pinpoint what kind of contamination it could be. Yes, 577 00:30:06,840 --> 00:30:09,280 Speaker 1: And it's very hard to measure the amount of tritium 578 00:30:09,280 --> 00:30:11,240 Speaker 1: in zenon. It's very hard to get it pure, and 579 00:30:11,320 --> 00:30:14,280 Speaker 1: it's very hard to isolate the tritium, and so they're 580 00:30:14,320 --> 00:30:16,960 Speaker 1: working on that. They're using all sorts of clever techniques 581 00:30:16,960 --> 00:30:20,480 Speaker 1: to try to isolate the treatium and measure its separately, etcetera, etcetera. 582 00:30:20,560 --> 00:30:23,400 Speaker 1: But this all could just be a bunch of puffery 583 00:30:23,480 --> 00:30:26,720 Speaker 1: around a little bit of contamination in their zenon, Okay, 584 00:30:26,720 --> 00:30:29,640 Speaker 1: because that's is that common to have tritium accidentally in 585 00:30:29,680 --> 00:30:32,600 Speaker 1: your xenon. I mean, I don't have any first hand experience. 586 00:30:33,960 --> 00:30:36,640 Speaker 1: I don't have any xenon in my house that I've purchased, 587 00:30:36,880 --> 00:30:39,800 Speaker 1: But yeah, I mean xenon is naturally occurring and it's 588 00:30:39,840 --> 00:30:42,800 Speaker 1: filtered out of the air, and in the process of 589 00:30:42,880 --> 00:30:46,720 Speaker 1: gathering xenon sometimes impurities come in and so it's pretty 590 00:30:46,720 --> 00:30:50,000 Speaker 1: hard to get like really really pure xenon. So it's 591 00:30:50,000 --> 00:30:52,600 Speaker 1: something they were aware of, obviously, something they were worried about, 592 00:30:52,920 --> 00:30:55,320 Speaker 1: and it is something that they can use to explain 593 00:30:55,760 --> 00:31:00,120 Speaker 1: this signature without invoking crazy new pink unicorn particles. So 594 00:31:00,120 --> 00:31:03,320 Speaker 1: they're working on nicely. But wouldn't that over time decrease, 595 00:31:03,360 --> 00:31:07,360 Speaker 1: like as all the tritium decays, that would go down eventually. 596 00:31:07,400 --> 00:31:09,160 Speaker 1: I suppose it would, but you know, this would be 597 00:31:09,280 --> 00:31:13,200 Speaker 1: enough tritium in there to provide this signal. I mean, 598 00:31:13,200 --> 00:31:16,200 Speaker 1: the tredium does have a pretty long half life, all right. 599 00:31:16,280 --> 00:31:19,480 Speaker 1: So that's the most boring, sorry, at least exciting, most 600 00:31:19,520 --> 00:31:23,600 Speaker 1: boring explanation for this result. And so what's the next 601 00:31:23,760 --> 00:31:26,400 Speaker 1: most exciting. The next most exciting is that maybe they 602 00:31:26,440 --> 00:31:29,760 Speaker 1: saw a weird kind of neutrino. Like we know the 603 00:31:29,800 --> 00:31:32,640 Speaker 1: new trinos are out there. We've ruled out new trinos 604 00:31:32,720 --> 00:31:35,320 Speaker 1: as dark matter because we know dark matter, if it's 605 00:31:35,360 --> 00:31:38,280 Speaker 1: a particle, has to be pretty heavy. It's men move 606 00:31:38,400 --> 00:31:41,440 Speaker 1: pretty slow. We know that because the way it's shaped 607 00:31:41,440 --> 00:31:43,760 Speaker 1: the whole structure of the universe. So we know the 608 00:31:43,800 --> 00:31:45,760 Speaker 1: neutrinos are out there, but there's not enough of them 609 00:31:45,760 --> 00:31:48,680 Speaker 1: to explain the dark matter and they have too much energy. 610 00:31:49,200 --> 00:31:52,280 Speaker 1: But people thought, you know, this huge device that we've 611 00:31:52,280 --> 00:31:55,400 Speaker 1: built is also a good way to see neutrinos. Like 612 00:31:55,440 --> 00:31:58,080 Speaker 1: if the neutrino flies through here and bounces into one 613 00:31:58,080 --> 00:32:01,200 Speaker 1: of these electrons, then we see that. That's how they 614 00:32:01,200 --> 00:32:02,960 Speaker 1: find the trinos in the first place, right, like a 615 00:32:02,960 --> 00:32:05,360 Speaker 1: big tub of something chill, Yeah, exactly, big tub of 616 00:32:05,400 --> 00:32:07,800 Speaker 1: something chill is a good way to find shy particle, 617 00:32:07,920 --> 00:32:11,200 Speaker 1: especially you put it underground so you don't get bombarded 618 00:32:11,280 --> 00:32:14,280 Speaker 1: by muans and all sorts of other stuff from cosmic rays. 619 00:32:14,720 --> 00:32:18,080 Speaker 1: And so it's very similar technology to all the neutrino experiments, 620 00:32:18,080 --> 00:32:20,480 Speaker 1: like we talked about the Doune experiment, which is, you know, 621 00:32:20,560 --> 00:32:24,840 Speaker 1: fundamentally very similar to this experiment. Equally cool acronym, equally 622 00:32:24,880 --> 00:32:27,760 Speaker 1: cool acronym. But to make this signature this sort of 623 00:32:27,800 --> 00:32:30,640 Speaker 1: like weird spike in their electron spectrum, they need a 624 00:32:30,680 --> 00:32:33,760 Speaker 1: particular kind of neutrino that we've never seen, which is 625 00:32:33,960 --> 00:32:37,920 Speaker 1: a neutrino with a little magnetic field, like a non 626 00:32:37,920 --> 00:32:41,960 Speaker 1: neutral neutrino. Yeah, neutrinos don't have electric charge, and we 627 00:32:42,080 --> 00:32:44,760 Speaker 1: think that the reason that particles have a magnetic field 628 00:32:44,840 --> 00:32:47,640 Speaker 1: is because they have both electric charge and this weird 629 00:32:47,760 --> 00:32:50,880 Speaker 1: quantum spin. So it's not that they're actually spinning with 630 00:32:50,920 --> 00:32:55,240 Speaker 1: there's some like weird particle analogy to spinning with charge. 631 00:32:55,280 --> 00:32:57,480 Speaker 1: It gives you a little magnetic field. And we talked 632 00:32:57,760 --> 00:33:00,280 Speaker 1: last week on the podcast about how a muan has 633 00:33:00,320 --> 00:33:03,040 Speaker 1: a little magnetic dipole in north and the south and 634 00:33:03,080 --> 00:33:07,440 Speaker 1: you can measure really precisely to learn secrets of the universe. Well, neutrinos, 635 00:33:07,560 --> 00:33:10,640 Speaker 1: we don't think they have them, but if there was 636 00:33:10,680 --> 00:33:14,160 Speaker 1: a kind of neutrino which did have a magnetic field, 637 00:33:14,440 --> 00:33:18,160 Speaker 1: it would give you this kind of signature a new neutrina, 638 00:33:18,320 --> 00:33:20,640 Speaker 1: a new kind of neutrino. Yeah, a neutrino that has 639 00:33:20,640 --> 00:33:23,200 Speaker 1: a little magnetic field. I see. And is that even 640 00:33:23,240 --> 00:33:26,200 Speaker 1: allowable in the sort of laws of physics or would 641 00:33:26,200 --> 00:33:28,960 Speaker 1: this totally be new and break that down. This would 642 00:33:29,000 --> 00:33:31,240 Speaker 1: be totally new, It would be crazy. You would have 643 00:33:31,320 --> 00:33:34,240 Speaker 1: to really rework the whole standard model to allow for 644 00:33:34,280 --> 00:33:37,720 Speaker 1: a neutrino that had any sort of like electromagnetic interactions, 645 00:33:38,080 --> 00:33:40,600 Speaker 1: it would break a lot of stuff. But that's exciting, right, 646 00:33:40,680 --> 00:33:42,600 Speaker 1: That's like, Hey, that's what we're doing this for. We're 647 00:33:42,600 --> 00:33:45,479 Speaker 1: doing this to break our understanding so we can rebuild it. Right, 648 00:33:45,560 --> 00:33:48,160 Speaker 1: That's that's what experimentalists are hoping to do, is to 649 00:33:48,200 --> 00:33:51,280 Speaker 1: find something new and crazy. You're like, break it, break 650 00:33:51,280 --> 00:33:54,760 Speaker 1: it exactly, but you know it's got to be real. 651 00:33:54,880 --> 00:33:57,200 Speaker 1: And when you think about this got a new idea, 652 00:33:57,280 --> 00:33:59,840 Speaker 1: you have to think like, well, if that existed, would 653 00:33:59,840 --> 00:34:01,840 Speaker 1: we see it somewhere else? Is there another way we 654 00:34:01,880 --> 00:34:04,440 Speaker 1: could have or should have spotted this? You know, are 655 00:34:04,480 --> 00:34:07,440 Speaker 1: you just trying to explain the fact that you didn't 656 00:34:07,440 --> 00:34:11,120 Speaker 1: really get pure zenon and make it sound dramatic. If 657 00:34:11,160 --> 00:34:14,600 Speaker 1: these new kinds of neutrinos existed, they would interact with 658 00:34:14,640 --> 00:34:17,680 Speaker 1: the zenon in a way that could maybe explain this 659 00:34:17,880 --> 00:34:20,880 Speaker 1: weird data. Yes, okay, so that that sounds pretty i 660 00:34:20,920 --> 00:34:23,560 Speaker 1: don't know, interesting in groundbreaking. But you're saying that there's 661 00:34:23,600 --> 00:34:26,520 Speaker 1: a third possibility, which is even crazier. That's right. And 662 00:34:26,560 --> 00:34:29,399 Speaker 1: so there's another idea, which is maybe they didn't see 663 00:34:29,480 --> 00:34:32,799 Speaker 1: dark matter, maybe they didn't see neutrinos. Maybe what they 664 00:34:32,800 --> 00:34:37,280 Speaker 1: saw where this weird particle called axions. We talked about 665 00:34:37,280 --> 00:34:40,640 Speaker 1: axons a couple of episodes ago. Right, they're detergent particles, right, 666 00:34:40,719 --> 00:34:45,440 Speaker 1: they clean up the other and Adams right there you go, 667 00:34:46,680 --> 00:34:49,239 Speaker 1: they do all the dirty work of the universe. Yeah, 668 00:34:49,280 --> 00:34:52,520 Speaker 1: They're a crazy particle invented to solve a problem in 669 00:34:52,600 --> 00:34:56,240 Speaker 1: theoretical physics. You know why two things seemed to balance 670 00:34:56,320 --> 00:34:58,400 Speaker 1: and we don't know why, and they invented this axion 671 00:34:58,600 --> 00:35:01,320 Speaker 1: to give those things balance. And then as a bonus, 672 00:35:01,320 --> 00:35:04,480 Speaker 1: people realized, hey, wait a second, maybe axons could be 673 00:35:04,520 --> 00:35:06,560 Speaker 1: the dark matter. And we talked about it on the 674 00:35:06,560 --> 00:35:09,359 Speaker 1: podcast a few weeks ago. And axions, if they exist, 675 00:35:09,440 --> 00:35:11,000 Speaker 1: there's sort of like a photon, but they have a 676 00:35:11,000 --> 00:35:13,799 Speaker 1: little bit of mass, but they're really really not very heavy. 677 00:35:13,840 --> 00:35:17,120 Speaker 1: They're like a tiny little bit of mass like one 678 00:35:17,200 --> 00:35:20,760 Speaker 1: one thousands of an electron bolt, which is very small 679 00:35:20,840 --> 00:35:23,560 Speaker 1: given that like an electron is like half a million 680 00:35:23,600 --> 00:35:26,759 Speaker 1: electron bolts. So these things, if they exist, would be like, 681 00:35:26,880 --> 00:35:30,839 Speaker 1: you know, a billion times less mass than the electron, right, 682 00:35:30,840 --> 00:35:32,319 Speaker 1: but you still sort of think of them as a 683 00:35:32,320 --> 00:35:36,480 Speaker 1: heavy photon like photon with mass. That's right, And if 684 00:35:36,520 --> 00:35:39,040 Speaker 1: axons are out there, then in order to be the 685 00:35:39,120 --> 00:35:42,080 Speaker 1: dark matter, they need to not be moving very fast. Right, 686 00:35:42,200 --> 00:35:45,400 Speaker 1: dark matter is cold and axons are very very low mass, 687 00:35:45,440 --> 00:35:49,840 Speaker 1: and so this experiment couldn't see dark matter axios. But 688 00:35:50,520 --> 00:35:52,960 Speaker 1: they said, all right, well we can't see dark matter axions. 689 00:35:53,120 --> 00:35:56,080 Speaker 1: What if there's a new weird kind of axion, like 690 00:35:56,400 --> 00:35:59,440 Speaker 1: one that's made in the sun and shot out with 691 00:35:59,480 --> 00:36:02,720 Speaker 1: a lot of energy, so like a hot axion. Wow, 692 00:36:02,800 --> 00:36:05,960 Speaker 1: it sounds like a reach. It's a bit of a reach. Yeah, 693 00:36:06,200 --> 00:36:09,759 Speaker 1: it's a bit of reach. Like, let's let's put on 694 00:36:09,800 --> 00:36:12,920 Speaker 1: all of our idea hats everyone, because we're gonna lose 695 00:36:12,960 --> 00:36:15,160 Speaker 1: funding if we don't come up with some cool idea. Yeah, 696 00:36:15,160 --> 00:36:17,239 Speaker 1: I thought you'd be impressed. It's sort of like you know, 697 00:36:17,600 --> 00:36:19,759 Speaker 1: physics engineering. They're like, all right, what if we take 698 00:36:19,800 --> 00:36:22,160 Speaker 1: a piece of this idea and we staple it to 699 00:36:22,239 --> 00:36:24,040 Speaker 1: that idea and then we hang the whole thing on 700 00:36:24,080 --> 00:36:26,920 Speaker 1: this third idea and it's sort of you know, we 701 00:36:26,960 --> 00:36:30,879 Speaker 1: need to do. Is that why you think of engineering? Yeah? 702 00:36:30,880 --> 00:36:33,480 Speaker 1: If you of engineering, like um, that's seen from a 703 00:36:33,520 --> 00:36:36,120 Speaker 1: Pollar thirteen where they're like, what if he's duct tape 704 00:36:36,320 --> 00:36:39,359 Speaker 1: to glue this tube over here. Exactly? Is that not? 705 00:36:39,840 --> 00:36:42,120 Speaker 1: Is that not the high water mark for engineering? I mean, 706 00:36:43,440 --> 00:36:45,200 Speaker 1: I'll let that pass. But then so you're saying, this 707 00:36:45,280 --> 00:36:50,240 Speaker 1: is like a creative physics here, creative you know problems, Yes, yes, exactly, 708 00:36:50,520 --> 00:36:52,719 Speaker 1: they're coming up. They're like, what can we do to 709 00:36:52,840 --> 00:36:55,920 Speaker 1: explain this weird signal in an exciting way? Because who 710 00:36:55,920 --> 00:36:58,120 Speaker 1: wants to write a boring paper about treatium. We want 711 00:36:58,120 --> 00:37:00,560 Speaker 1: to write a paper saying, maybe we discover this crazy 712 00:37:00,600 --> 00:37:03,080 Speaker 1: new thing that nobody ever thought could exist, but we 713 00:37:03,160 --> 00:37:05,960 Speaker 1: might have broken open the universe, meaning because because if 714 00:37:06,000 --> 00:37:09,520 Speaker 1: you do find this axon, this new kind of potential 715 00:37:09,600 --> 00:37:13,239 Speaker 1: hypothetical particle. So it's like a hypothesis and a hypothesis, right, 716 00:37:13,560 --> 00:37:15,399 Speaker 1: So I do you do find it? That would break 717 00:37:15,440 --> 00:37:17,480 Speaker 1: the loss of physics? Well, it would be hard to 718 00:37:17,520 --> 00:37:20,960 Speaker 1: explain because nobody knows why axons would be produced in 719 00:37:21,000 --> 00:37:24,120 Speaker 1: the sun. And if they were produced in the sun 720 00:37:24,239 --> 00:37:27,040 Speaker 1: in order to have enough speed to be seen by 721 00:37:27,120 --> 00:37:30,959 Speaker 1: the Xenon experiment, then it would be cooled down the Sun. 722 00:37:31,200 --> 00:37:33,879 Speaker 1: I could be pumping out a lot of energy, and 723 00:37:33,960 --> 00:37:36,879 Speaker 1: we would expect stars in the sky to fade out 724 00:37:37,080 --> 00:37:40,880 Speaker 1: much faster than we see So the solar axon is 725 00:37:40,880 --> 00:37:44,640 Speaker 1: sort of already disfavored by lots of things in physics. 726 00:37:44,680 --> 00:37:49,080 Speaker 1: It's sort of like contradicted by astrophysical measurements already. So 727 00:37:49,960 --> 00:37:52,160 Speaker 1: if it does exist, it would be Yeah, if it 728 00:37:52,200 --> 00:37:54,439 Speaker 1: does exist, it means we need to re understand how 729 00:37:54,520 --> 00:37:57,600 Speaker 1: stars work, which is hey, that's exciting, and we need 730 00:37:57,640 --> 00:37:59,840 Speaker 1: to understand like why stars are making this axon and 731 00:38:00,120 --> 00:38:02,319 Speaker 1: this actually exists in this way, so that it would 732 00:38:02,360 --> 00:38:05,879 Speaker 1: be a pretty big discovery. If solar axons were real. 733 00:38:05,920 --> 00:38:08,319 Speaker 1: It would make us rethink a lot of stice. You 734 00:38:08,360 --> 00:38:10,800 Speaker 1: have to rethink not just the standard model, but also 735 00:38:10,880 --> 00:38:13,440 Speaker 1: like how stars work. Yeah, and we've gotten pretty good 736 00:38:13,440 --> 00:38:15,640 Speaker 1: at understanding how stars work. You know, we have a 737 00:38:15,640 --> 00:38:17,680 Speaker 1: good model for how they burn and how they die 738 00:38:18,080 --> 00:38:20,319 Speaker 1: and the various kinds of stars that are out there, 739 00:38:20,640 --> 00:38:22,319 Speaker 1: and so this would throw a wrench in like a 740 00:38:22,360 --> 00:38:25,480 Speaker 1: pretty well established field. Right. So that's pretty exciting to 741 00:38:25,520 --> 00:38:28,200 Speaker 1: be at a time when you know, an experiment like 742 00:38:28,239 --> 00:38:31,520 Speaker 1: this that's high profile, find something unexpected, and it could 743 00:38:31,520 --> 00:38:33,880 Speaker 1: be some pretty amazing things. Yeah, it could be. But 744 00:38:34,000 --> 00:38:36,359 Speaker 1: you know, my personal opinion is that this is a 745 00:38:36,360 --> 00:38:39,240 Speaker 1: big reach. You know, they see something weird in their data. 746 00:38:39,600 --> 00:38:41,400 Speaker 1: It's cool, but you know, we see weird stuff in 747 00:38:41,440 --> 00:38:44,120 Speaker 1: our data all the time, and usually it's because we 748 00:38:44,160 --> 00:38:47,600 Speaker 1: didn't really understand the backgrounds. We didn't really understand the 749 00:38:47,640 --> 00:38:50,560 Speaker 1: performance of our instrument. There was something weird going on, 750 00:38:50,680 --> 00:38:54,480 Speaker 1: it was miscalibrated or some other source of these events 751 00:38:54,480 --> 00:38:56,960 Speaker 1: that we didn't anticipate. And so you've got to be 752 00:38:57,000 --> 00:38:59,800 Speaker 1: really skeptical. And that's why we have a really high 753 00:38:59,800 --> 00:39:03,000 Speaker 1: threshold for believing that something there is new, Like, first 754 00:39:03,000 --> 00:39:04,960 Speaker 1: of all, you have to see it in another experiment. 755 00:39:04,960 --> 00:39:07,560 Speaker 1: An independent experiment would have to see the same thing, 756 00:39:07,800 --> 00:39:12,040 Speaker 1: hopefully using slightly different technologies or you know, being differently 757 00:39:12,080 --> 00:39:15,120 Speaker 1: sensitive to sources of bias. And the other thing that 758 00:39:15,160 --> 00:39:17,080 Speaker 1: makes me wonder about this is if you have a 759 00:39:17,160 --> 00:39:18,959 Speaker 1: chance to google it and to look at the data, 760 00:39:19,000 --> 00:39:21,120 Speaker 1: you see that it all sort of piles up right 761 00:39:21,160 --> 00:39:23,520 Speaker 1: on the edge of where they can see. You know, 762 00:39:23,560 --> 00:39:26,640 Speaker 1: they can see electrons down to a certain energy, and 763 00:39:26,640 --> 00:39:28,920 Speaker 1: then below that they just can't detect them, and all 764 00:39:29,000 --> 00:39:31,319 Speaker 1: these things pile up right on the edge of where 765 00:39:31,360 --> 00:39:33,759 Speaker 1: they're able to see, which always makes me suspicious, like 766 00:39:34,000 --> 00:39:36,080 Speaker 1: do you really know what's going on at the very 767 00:39:36,120 --> 00:39:39,560 Speaker 1: extreme ends of your detector. So it just makes me 768 00:39:39,640 --> 00:39:41,799 Speaker 1: wonder if really, in the end, this this is an 769 00:39:41,840 --> 00:39:44,960 Speaker 1: issue of understanding your detector response, I see, because I 770 00:39:44,960 --> 00:39:47,719 Speaker 1: guess there's a secret option D, which is that it's 771 00:39:47,719 --> 00:39:50,160 Speaker 1: just nothing. Yeah, that's just nothing, which is just like 772 00:39:50,200 --> 00:39:53,399 Speaker 1: they just didn't calibrate it well, or you know, it's 773 00:39:53,440 --> 00:39:56,239 Speaker 1: different than they were expecting because what they were expecting 774 00:39:56,560 --> 00:39:58,560 Speaker 1: was wrong. Yeah. And I don't mean that they didn't 775 00:39:58,560 --> 00:40:00,719 Speaker 1: do their jobs well or that they're not smart. This 776 00:40:00,800 --> 00:40:03,719 Speaker 1: is super duper hard. They're doing something nobody else has 777 00:40:03,760 --> 00:40:06,560 Speaker 1: ever done before. They're not just like ordering something from 778 00:40:06,560 --> 00:40:09,960 Speaker 1: Amazon and turning it on right. They're pushing the which 779 00:40:10,000 --> 00:40:13,759 Speaker 1: is basically engineering. It sounds like you said, you think 780 00:40:13,840 --> 00:40:18,359 Speaker 1: that no engineering would be ordering six different weird things 781 00:40:18,360 --> 00:40:20,879 Speaker 1: from Amazon and making them do something else That would 782 00:40:20,920 --> 00:40:24,480 Speaker 1: be awesome engineering. But now these folks are pushing the 783 00:40:24,480 --> 00:40:27,439 Speaker 1: boundaries of what can be done. They've won the race 784 00:40:27,520 --> 00:40:30,240 Speaker 1: to get like the one Ton experiment up and running 785 00:40:30,320 --> 00:40:33,799 Speaker 1: and working and with this new clever technique. And so 786 00:40:34,120 --> 00:40:36,759 Speaker 1: I'm not criticizing them at all, But often when you're 787 00:40:36,800 --> 00:40:39,759 Speaker 1: on the bleeding edge, you don't understand the data that 788 00:40:39,800 --> 00:40:41,480 Speaker 1: comes in at first and it takes a wild to 789 00:40:41,520 --> 00:40:43,799 Speaker 1: figure it out and to really damp it down. So 790 00:40:44,080 --> 00:40:45,839 Speaker 1: that's where they are, and they don't know if this 791 00:40:46,040 --> 00:40:49,080 Speaker 1: signature means, hey, the universe is telling you a deep 792 00:40:49,120 --> 00:40:52,320 Speaker 1: secret that it's been waiting to reveal for fourteen billion years, 793 00:40:52,680 --> 00:40:54,600 Speaker 1: or you know, you got to twist that novel a 794 00:40:54,640 --> 00:40:58,000 Speaker 1: little harder because the experiment is not quite tightened up, 795 00:40:58,280 --> 00:41:00,520 Speaker 1: and you're gotta chill that zeno in a little bit more. Yeah, 796 00:41:00,560 --> 00:41:03,839 Speaker 1: it could be, but fortunately we do have more experiments coming. 797 00:41:04,120 --> 00:41:06,520 Speaker 1: There's an experiment in the US that's coming up. It's 798 00:41:06,520 --> 00:41:10,040 Speaker 1: called l Z and it's got basically the same strategy, 799 00:41:10,080 --> 00:41:13,200 Speaker 1: a big tub of liquid zinn. And there's one in 800 00:41:13,320 --> 00:41:17,680 Speaker 1: China called Panda X that's underground. That's huge. And so 801 00:41:17,840 --> 00:41:20,319 Speaker 1: if this is real, they should also see it and 802 00:41:20,360 --> 00:41:22,520 Speaker 1: we'll hear more from them soon. Right, Is it a 803 00:41:22,520 --> 00:41:24,360 Speaker 1: requirement that they need to use some of the letters 804 00:41:24,360 --> 00:41:28,959 Speaker 1: from the end of the alphabet, like Z X Why, well, 805 00:41:29,000 --> 00:41:31,239 Speaker 1: you know it's xenon and so they've got to have 806 00:41:31,280 --> 00:41:34,440 Speaker 1: an X in there somewhere, right, because x is are awesome. 807 00:41:36,080 --> 00:41:39,759 Speaker 1: They marked the spot out here exactly. They're exciting, all right, Well, 808 00:41:39,760 --> 00:41:43,240 Speaker 1: it sounds like stay tuned is the answer to this question. 809 00:41:43,560 --> 00:41:46,720 Speaker 1: But it's got physicists excited, and it could mean that 810 00:41:47,320 --> 00:41:50,800 Speaker 1: we need to rethink our signs that we have about 811 00:41:50,840 --> 00:41:53,400 Speaker 1: the universe, you know, part of either the standard model 812 00:41:53,520 --> 00:41:57,200 Speaker 1: or how stars work, or what kinds of netrinas there 813 00:41:57,200 --> 00:42:00,359 Speaker 1: could be. So that's pretty exciting. Or it could be 814 00:42:00,440 --> 00:42:02,919 Speaker 1: just that we need more data. Yeah, I hope it's 815 00:42:02,920 --> 00:42:06,120 Speaker 1: something new. I hope that it's a it breaks physics 816 00:42:06,160 --> 00:42:09,200 Speaker 1: and teaches us something about the universe. I'm pretty skeptical 817 00:42:09,360 --> 00:42:12,560 Speaker 1: frankly then it's anything real. So but stay tuned and 818 00:42:12,760 --> 00:42:15,759 Speaker 1: keep an open mind and an open heart, because that's 819 00:42:15,760 --> 00:42:18,600 Speaker 1: why we do this stuff. We're asking the universe questions 820 00:42:18,680 --> 00:42:20,480 Speaker 1: and we have to listen to what it tells us. 821 00:42:20,680 --> 00:42:23,799 Speaker 1: All right, Well, we hope that answered the question, and 822 00:42:23,840 --> 00:42:25,799 Speaker 1: we hope it provide it's some interesting things. Who think 823 00:42:25,800 --> 00:42:27,400 Speaker 1: about for those of you who had not heard of 824 00:42:27,400 --> 00:42:30,839 Speaker 1: this experiment, so stay tuned for more exciting us. That's right, 825 00:42:30,880 --> 00:42:34,759 Speaker 1: because this dark tub liquid underground might be shedding light 826 00:42:34,880 --> 00:42:37,319 Speaker 1: on dark matter. There might be a unicorn bathing in it. 827 00:42:39,160 --> 00:42:44,240 Speaker 1: That is a very strange mental image, A big unicorn 828 00:42:44,280 --> 00:42:46,399 Speaker 1: with an ex painting on its chest. I don't think 829 00:42:46,440 --> 00:42:48,800 Speaker 1: that's ethical treatment of unicorns. To put them in a 830 00:42:48,880 --> 00:42:51,720 Speaker 1: dark bathtub of mile underground, that's what they like, Daniel, 831 00:42:51,920 --> 00:42:56,560 Speaker 1: Maybe we have to rethink our understanding of unicorns. I 832 00:42:56,600 --> 00:42:59,520 Speaker 1: think the Society for the Ethical Protection of Unicorns is 833 00:42:59,520 --> 00:43:06,000 Speaker 1: going to be what's the acronym for that society? UM, 834 00:43:06,040 --> 00:43:09,320 Speaker 1: I'll pass that one on to my creative partner. All right, Well, 835 00:43:09,320 --> 00:43:11,680 Speaker 1: we hope you enjoyed that. Thanks for joining us, see 836 00:43:11,680 --> 00:43:22,080 Speaker 1: you next time. Thanks for listening, and remember that Daniel 837 00:43:22,120 --> 00:43:24,640 Speaker 1: and Jorge explained. The Universe is a production of I 838 00:43:24,880 --> 00:43:28,319 Speaker 1: Heart Radio. For more podcast For my heart Radio, visit 839 00:43:28,320 --> 00:43:31,840 Speaker 1: the I Heart Radio Apple Apple Podcasts, or wherever you 840 00:43:31,920 --> 00:43:39,040 Speaker 1: listen to your favorite shows. Ye