Speaker 1: Welcome to text Stuff, a production from I Heart Radio.
Speaker 1: Hey there, and welcome to tech Stuff. I'm your host,
Speaker 1: Jonathan Strickland. I'm an executive producer with I Heart Radio
Speaker 1: and I love all things tech. And if you guys
Speaker 1: have listened to tech Stuff or any real length of time,
Speaker 1: you know that I talk a lot about how miniaturization
Speaker 1: really changed everything. You could argue it fueled a new
Speaker 1: industrial revolution. So in the early twentieth century, technology like radios, televisions,
Speaker 1: and computers were all bigger because they had to be,
Speaker 1: because the internal components inside these technologies, the things that
Speaker 1: made these technologies work, were themselves much larger. That's why
Speaker 1: you would buy a television that had a tiny ten
Speaker 1: inch screen housed inside a cabinet large enough to be
Speaker 1: a full piece of furniture. The invention of the transistor
Speaker 1: would lead to manturization, and in less than one years
Speaker 1: we would find ourselves holding a device in our hands
Speaker 1: that was vastly more powerful than the massive computers that
Speaker 1: took up entire floors of buildings back in the day.
Speaker 1: But what if we keep going down that path. What
Speaker 1: if we were to mantorize things even more? What if
Speaker 1: we could get technology down to a scale so small
Speaker 1: that it would be too tiny for us to see.
Speaker 1: What have we conquered the nano scale? So in today's episode,
Speaker 1: I'm going to explain what nanotechnology is all about and
Speaker 1: how the idea evolved, and a bit about where we
Speaker 1: are now. We'll also talk about how stuff gets really
Speaker 1: weird when you get really small, which I think any
Speaker 1: toddler would attest to, but I mean, it gets really
Speaker 1: weird when you get really small. In fact, if you
Speaker 1: want to get super lucy goosey with the term nanotechnology,
Speaker 1: it gives us a chance to talk about those weird
Speaker 1: things right now. But first a definition. Technically speaking, nanotechnology
Speaker 1: encompasses tech that is on a size scale of one
Speaker 1: d nanometers or smaller down to one nanometer. A nanometer
Speaker 1: is one billionth of a meter. A strand of human
Speaker 1: hair ranges between eighty thousand and one hundred thousand nanometers
Speaker 1: in width. So if you take one of your hairs
Speaker 1: because you can't take mine I'm bald, and you were
Speaker 1: to hold your hair and look at how wide that
Speaker 1: strand of hair is, not how long? How wide? That's
Speaker 1: eight thousand to ten thousand times wider than what we're
Speaker 1: talking about here. In addition, we often think of nanotechnology
Speaker 1: today as being a branch of science and tech that
Speaker 1: is exploring the possibility of manipulating matter on the molecular
Speaker 1: or even atomic scale. The classic example of this in
Speaker 1: science fiction is the universal Assembler, a device that can
Speaker 1: construct macro sized objects atom by atom or molecule by molecule.
Speaker 1: And we'll cover those in more detail a little bit later,
Speaker 1: but this is sort of how the replicators are on
Speaker 1: Star Trek are supposed to work. Right, You say t
Speaker 1: earl gray hot, and then the device takes all the
Speaker 1: atoms that are necessary to make that, puts them together
Speaker 1: right there when you're waiting, and boom, you have t
Speaker 1: on demand. But we don't have to wait until the
Speaker 1: twenty second century to talk about our work in nanotechnology.
Speaker 1: In fact, we can go back more than three thousand
Speaker 1: years ago in China and talk about lamp black. Now,
Speaker 1: this material is a byproduct of burning oil, typically a
Speaker 1: coal based oil, and burning oil in a shallow and
Speaker 1: where you produce really heavy smoke was the typical production
Speaker 1: method for lamp black. You would use a collection pan
Speaker 1: that you would put near the flame, and the collection
Speaker 1: pan begins to accumulate very small particles of carbon they
Speaker 1: are deposited on that pan. Some of those particles are
Speaker 1: around twenty nanometers in diameter. So the lamp black has
Speaker 1: a pretty phenomenal surface area to volume ratio, right, because
Speaker 1: the particles are very small, So there's more of the
Speaker 1: surface of the particle exposed to the air than there
Speaker 1: is under the surface. One way to think about this
Speaker 1: is if you have a gold brick that has a
Speaker 1: certain amount of surface that's exposed to the air. Right,
Speaker 1: But if you were to make that gold brick into
Speaker 1: gold foil, right, if you were to flatten it out
Speaker 1: so that it's much much, much much wider, much much longer,
Speaker 1: but very e than well, now, way more of the
Speaker 1: surface of that gold is exposed to the outside world
Speaker 1: as a much larger amount of surface area compared to
Speaker 1: its volume. Well, that's kind of how things are on
Speaker 1: the nano scale. Nanoparticles have way more surface area exposed
Speaker 1: to the world compared to their volume than stuff that's
Speaker 1: on the macro scale. All right, let's get back to
Speaker 1: lamp black. So because of this amazing amount of surface area,
Speaker 1: it became a very popular black pigment for inks. And paints.
Speaker 1: You didn't need a lot of it in order to
Speaker 1: be able to cover a surface. Well, if it's black,
Speaker 1: then you could use that to be an ink. Right
Speaker 1: centuries later, this same sort of stuff, which we typically
Speaker 1: now call carbon black, is used in all kinds of applications,
Speaker 1: including printer toner. So even to this day we're using
Speaker 1: the same sort of stuff, these tiny, tiny particles of carbon.
Speaker 1: Way back in the three as in the four century
Speaker 1: Common era, some Roman artisan crafted a cup made out
Speaker 1: of glass. Now that in itself isn't incredibly special, but
Speaker 1: this particular cup had a really cool quality to it.
Speaker 1: So let's say you had the glass sitting on a
Speaker 1: table and you placed an oil lamp in front of
Speaker 1: the glass, so it's between you and the glass. Then
Speaker 1: to you, the glass would appear to be green. But
Speaker 1: let's say you position the glass so that the light
Speaker 1: from the oil lamp was actually going into the glass
Speaker 1: rather than onto it. Well, now the glass would appear
Speaker 1: to be red. The color of the glass changes depending
Speaker 1: upon how light hits it. Now today we call the
Speaker 1: glass by the name the Lakergus cup, and you can
Speaker 1: see the Lakergus cup if you ever go into the
Speaker 1: British Museum. Maybe not right now, but you know, things
Speaker 1: being what they are, but when things get better, you
Speaker 1: could see it there. That's where the cup is. It's
Speaker 1: called the Lakergus cup because the figure on the cup
Speaker 1: is that of King like Urgus. He's being dragged into
Speaker 1: the underworld by the nymph ambrosia. So that's fun. So
Speaker 1: why does the glass change color and what does it
Speaker 1: have to do with nanotechnology? The answers had to wait
Speaker 1: more than fifteen hundred years before we really sussed it out.
Speaker 1: In n scientists used an atomic force microscope more on
Speaker 1: those later to examine the like Hurgis cup, and they
Speaker 1: found that this glass contained extremely tiny particles of copper, gold,
Speaker 1: and silver. The particles were in the nanoscale range, and
Speaker 1: they were mixed in with the glass itself. The red
Speaker 1: light came from gold's absorption of light. The glass was
Speaker 1: a type of nanocomposite material. In the following centuries, glassmakers
Speaker 1: would experiment by adding different types of metals to glass
Speaker 1: mixtures to produce various colors of glass a k A
Speaker 1: stained glass. But while we were are able to grind
Speaker 1: stuff down to such a fine powder as to have
Speaker 1: individual particles on the nano scale suspended in glass. It
Speaker 1: wasn't like we were building machines at that same scale.
Speaker 1: That would have been unthinkable. In fact, I would argue
Speaker 1: that before the transistor, most folks weren't really thinking about
Speaker 1: going small with technology. Before the electronic era, we were
Speaker 1: building mechanical systems, and generally the power of machines scaled
Speaker 1: with their size. You could do stuff with gear ratios
Speaker 1: to help boost output without making an entire piece of
Speaker 1: technology bigger, but that only worked down to a certain point.
Speaker 1: In the early era of computers, even as we moved
Speaker 1: from the electro mechanical systems to pure electronic ones, the
Speaker 1: general thought was that the more powerful machines of tomorrow
Speaker 1: would be at least the same size, if not larger,
Speaker 1: than the behemoths of that era. Mantorization was something that
Speaker 1: most people just didn't really anticipate. That, by the way,
Speaker 1: is something that we should keep in mind whenever we
Speaker 1: make any predictions about the future, is that frequently things
Speaker 1: we don't anticipate will end up being a much larger
Speaker 1: influence on the way technology develops than what is currently
Speaker 1: going on. So in the nineteen twenties, if you were
Speaker 1: predicting what the future of technology was going to be,
Speaker 1: You probably weren't thinking in terms of electronics. That was unanticipated.
Speaker 1: And just like if we project out now, we say
Speaker 1: was it going to be like fifty years from now?
Speaker 1: If we're basing it on the technologies we're using right
Speaker 1: at this moment, chances are we're going to miss something
Speaker 1: because it's something we haven't early anticipated that's going to
Speaker 1: change everything between now and then. Okay, anyway, in our
Speaker 1: history we get up to nineteen forty seven when William Shockley,
Speaker 1: Walter Britain, and John Bardine, among others, developed the first
Speaker 1: transistor in a T and T S research and development
Speaker 1: division that would be Bell Labs. The transistor could step
Speaker 1: in and do the job that was previously performed by
Speaker 1: larger components like vacuum tubes. Vacuum tubes are still in
Speaker 1: use today, but the transistors largely replaced them in many technologies.
Speaker 1: So early transistors were large and impractical for any real application.
Speaker 1: They were, you know, a demonstration of a scientific principle,
Speaker 1: but you wouldn't actually use them for something like a radio. However,
Speaker 1: it did prove that the science underlying the transistors was sound,
Speaker 1: and it was only a matter of time before companies
Speaker 1: began to refine the technology and built smaller transistors and
Speaker 1: develop new manufacturing processes to do so at a scale
Speaker 1: large enough for them to be actually be useful. We'll
Speaker 1: get to a famous observation that Gordon Moore made because
Speaker 1: of this particular trend in a little bit, but there's
Speaker 1: another person that I need to talk about first. In
Speaker 1: nineteen fifty nine, physicist Richard Feynman gave a presentation at
Speaker 1: the American Physical Society at the California Institute of Technology
Speaker 1: also known as cal Tech. He called the presentation There's
Speaker 1: plenty of room at the bottom. It would retroactively become
Speaker 1: one of the foundational arguments in support of nanotechnology, the
Speaker 1: discipline and the pursuit of it. Now, it helps if
Speaker 1: we understand how things had developed by the time Feinman
Speaker 1: gave this talk. It took centuries for humans to develop
Speaker 1: technologies that allowed us to observe the world of the
Speaker 1: very small. From magnifying glasses to microscopes, we gradually peeled
Speaker 1: back the unknown, and we kept finding, to our amazement
Speaker 1: that things could get even smaller. But light based or
Speaker 1: optical microscopes have fundamental limitations that are dictated by physics.
Speaker 1: It's not because the limitations of the materials we used.
Speaker 1: It's not that we couldn't find clearer lenses or anything.
Speaker 1: It's rather due to the fact that light waves themselves
Speaker 1: have limitations. Now, we can see stuff because light bounces
Speaker 1: off of it, and light waves are very short. They
Speaker 1: are tiny, but they're not as tiny as say, individual atoms.
Speaker 1: Light waves are too big to reflect off of stuff
Speaker 1: as small as atoms and most molecules, and so no
Speaker 1: matter how good your optical microscope is, you're not going
Speaker 1: to be able to resolve images at that smallest scale
Speaker 1: just because you're using light. Typically you'd be relying on
Speaker 1: light with wavelengths of between four hundred and seven hundred nanometers.
Speaker 1: But that's way larger than stuff like proteins or some viruses,
Speaker 1: and and way way larger than atoms. If you want
Speaker 1: to observe these smaller things, you got to shed your
Speaker 1: dependence on light. Back in nineteen twenty six, a German
Speaker 1: scientist named Hans Bush developed the first electromagnetic lens. This
Speaker 1: isn't the same sort of lens you would find in
Speaker 1: eyeglasses or a telescope or a microscope. Instead, it was
Speaker 1: a couple of electro magnets which could generate a magnetic
Speaker 1: field sufficient to direct a beam of magnetically charged particles.
Speaker 1: This is the same sort of idea used in particle accelerators.
Speaker 1: In a particle accelerator, you've got these big, powerful magnets
Speaker 1: that create an extremely narrow channel through which charged particles
Speaker 1: can travel. They can't go outside of it because of
Speaker 1: these magnetic forces, and it guides the particles around a
Speaker 1: pathway so that they can collide with something else, such
Speaker 1: as a beam of charged particles that are traveling in
Speaker 1: the opposite direction. Now, Bush proposed using the lens to
Speaker 1: make a microscope that would use electrons rather than light,
Speaker 1: and electromagnetic coils rather than a glass lens. He even
Speaker 1: patented a design, but he never constructed the electron micro scope.
Speaker 1: Max Knell, an electrical engineer, and Ernst risk a physicist,
Speaker 1: did build one in ninety one, though this early version
Speaker 1: wasn't able to produce an image that was at a
Speaker 1: higher resolution than what you could achieve with an optical microscope.
Speaker 1: Those would come not that much longer down the road. However,
Speaker 1: the sample that you're looking at has to be inside
Speaker 1: a vacuum chamber, because air molecules would be like giant
Speaker 1: obstacles to an electron beam, and you wouldn't look at
Speaker 1: it through an eyepiece, you know, it's not like that
Speaker 1: type of microscope. Instead, you would capture the interactions of
Speaker 1: the electron beam with the sample you're examining on either
Speaker 1: special photographic film or later on a monitor. So typically
Speaker 1: you would have a sensor and then the sensor would
Speaker 1: send data that you would then interpret visually through a monitor.
Speaker 1: By the time Feynman gave his presentation in the late
Speaker 1: nineteen fifties, electron microscopes could produce images at a much
Speaker 1: smaller scale than optical microscopes. What scientists had learned from
Speaker 1: mathematics was actually beginning to bear out through observation. So
Speaker 1: sometimes we discover stuff because mathematically we understand that it
Speaker 1: has to be a certain way, even if we can't
Speaker 1: directly observe that way. That was kind of what was
Speaker 1: going on. We had sort of sussed out how the
Speaker 1: world had to be at that scale, and now we
Speaker 1: could actually directly observe it and learn even more. We
Speaker 1: appeared to be on the cusp of another major breakthrough.
Speaker 1: The crux of Fineman's presentation was all about the manipulation
Speaker 1: and controlling of the world on the small scale. He
Speaker 1: started off by talking about the possibility of printing something
Speaker 1: like a full encyclopedia onto the head of a pen.
Speaker 1: Then he elaborated from there. He talked about the possibility
Speaker 1: of printing twenty four million books, which he estimated to
Speaker 1: be about the number of notable books ever written, and
Speaker 1: printing them onto the equivalent of thirty five sheets of
Speaker 1: paper by making the print that tiny. His point was
Speaker 1: all about scale, that the scale of things we deal
Speaker 1: with in our everyday lives is gargantuan compared to what
Speaker 1: we could study with the help of powerful technologies like
Speaker 1: electron microscopes. He went on to hypothesize that if we
Speaker 1: were to develop a means of manipulating single atoms, you
Speaker 1: could encode information using some form of simple system. He
Speaker 1: likened it to the dots and dashes in Morse code,
Speaker 1: and you could use it in a three dimensional space
Speaker 1: for each character, and it would measure five by five
Speaker 1: by five atoms to a bit of information, and even
Speaker 1: while using additional atoms for separation, you could print the
Speaker 1: equivalent of those twenty four million volumes on a particle
Speaker 1: the size of a moat of dust. Feynman then goes
Speaker 1: on to suggest even more radical ideas, including using evaporation
Speaker 1: to reduce materials down to their smallest components, before then
Speaker 1: depositing those materials onto a substrate to build out wires
Speaker 1: and insulation and entire circuits. This way. Now, this is
Speaker 1: pretty similar to how we would make stuff like computer
Speaker 1: chips in the future, once we got all those technologies
Speaker 1: down to work on the nano scale. Fineman goes on
Speaker 1: in his presentation to propose the possibility that we could
Speaker 1: build mechanical systems at the nano scale, using the example
Speaker 1: of an automobile, saying how would it be possible to
Speaker 1: build that on this very tiny scale? He argued that
Speaker 1: such a thing might be hypothetically possible, but it would
Speaker 1: require some big changes in automobile design, and a tiny
Speaker 1: scale heat would dissipate much faster than at the macro scale. Again,
Speaker 1: you've got an incredible amount of surface area compared to volume,
Speaker 1: so an internal combustion engine wouldn't work. You wouldn't be
Speaker 1: able to get combustion. You would need some other sort
Speaker 1: of reaction to provide the energy needed to do work. Ultimately,
Speaker 1: Feynman suggested we might find a way to build such
Speaker 1: small devices as to be able to assemble matter atom
Speaker 1: by atom, building with precision on an atomic level, and
Speaker 1: that could create countless possible applications, including being able to
Speaker 1: synthesize chemicals, which previously we had to do through chemical synthesis,
Speaker 1: which is not necessarily as precise and fascinating idea. I'll
Speaker 1: talk a bit more about it, but first let's take
Speaker 1: a quick break. Fineman imagined a macro sized tool that
Speaker 1: could make essentially the parts to replicate itself, but on
Speaker 1: a much smaller scale. So imagine using a tool like
Speaker 1: a lathe to cut out all the parts for a
Speaker 1: smaller version of the lathe. Then you use this smaller
Speaker 1: lathe to cut out even smaller parts for an even
Speaker 1: smaller lathe, and so on, and then using these tiny
Speaker 1: tools to produce what Fineman called tiny hands to a symbol,
Speaker 1: very small components. But then he said, we'd start to
Speaker 1: encounter some challenges that don't exist in any appreciable way
Speaker 1: on the macro scale. For example, once you get down
Speaker 1: to the molecular level, you begin to encounter forces that
Speaker 1: you just don't notice at larger scales, forces like the
Speaker 1: Vanderwall's forces. These are electric forces that attract neutral molecules
Speaker 1: to one another. They are pretty weak forces, but when
Speaker 1: you get down to the molecular level, the forces are
Speaker 1: strong enough to cause issues. So he said, if you
Speaker 1: were to create the equivalent of a nut and bolt
Speaker 1: at the nano scale, you would find the Vanderwall's force
Speaker 1: strong enough that you would have trouble turning the nut
Speaker 1: like it would be difficult to tighten or loosen it
Speaker 1: because it would be clinging to the bolt due to
Speaker 1: the Vanderwall's force between the two. Now that's just the beginning.
Speaker 1: Of course. When you get down to the nano scale,
Speaker 1: you start to enter into a world governed more by
Speaker 1: quantum mechanics then the classical physics that you and I
Speaker 1: encounter in our day to day lives. Weird stuff starts
Speaker 1: to happen. At least it's weird to us because we
Speaker 1: don't observe the world working in that way on our scale. So,
Speaker 1: for example, there's the truly weird phenomena of quantum tunneling.
Speaker 1: I'll try to explain this as best I can. So
Speaker 1: let's start with the classical world, because we generally have
Speaker 1: a pretty good handle on that. Imagine you have a
Speaker 1: toy car, like a little matchbox car, and you've set
Speaker 1: up a ramp, and you probably understand that unless you
Speaker 1: push the toy car hard enough, it's not gonna make
Speaker 1: it up that ramp. It's not going to spontaneously go
Speaker 1: forward and climb that ramp. If you push too soft,
Speaker 1: then it's going to start going up the ramp and
Speaker 1: then roll back down. So the potential energy of the
Speaker 1: ramp is a certain level. You have to give enough
Speaker 1: kinetic energy to the toy car so it can overcome
Speaker 1: the potential energy g represented by the height and the
Speaker 1: and the slope of the ramp. Now let's say we're
Speaker 1: doing something similar, except instead of a little toy car
Speaker 1: and a ramp, we've got an electron and an electrical field.
Speaker 1: If the energy of the electron is higher than the
Speaker 1: energy level of the electric field, the electron can pass
Speaker 1: through it. But if the electric fields energy is higher,
Speaker 1: the electron will be repelled, just as the toy car
Speaker 1: would roll backward down the ramp if you didn't give
Speaker 1: it a hard enough push. But there's a tiny little problem.
Speaker 1: You see, at the quantum level, we're not talking in absolutes,
Speaker 1: we're actually talking in probabilities. Heisenberg's uncertainty principle explained that
Speaker 1: we'll never know the precise position and momentum of a
Speaker 1: particle like an electron. We can only know a little
Speaker 1: bit about each and then we can work out the
Speaker 1: probability that a given sub atomic particle is in a
Speaker 1: certain position at any given time. So you can actually
Speaker 1: plot this out in a wave function. The peak of
Speaker 1: the wave corresponds with the most likely outcomes, the places
Speaker 1: where the electron is most probably going to be located
Speaker 1: at a given time, but there will be a small
Speaker 1: chance that the electron will appear somewhere else. And if
Speaker 1: the wave function can actually overlap the entirety of the
Speaker 1: electric field, that means that there's a tiny little amount
Speaker 1: of that probability wave on the opposite side of the
Speaker 1: electric field where the electron could exist. The probability is
Speaker 1: very small, but it is there, which means it is
Speaker 1: possible the electron is on the other side of the
Speaker 1: electric field. And if something is possible, then if you
Speaker 1: do that something enough times it means it will happen.
Speaker 1: It probably doesn't happen frequently. The probability tells us it won't,
Speaker 1: but if there is a chance it will happen sooner
Speaker 1: or later, it will. Now, there's a lot more to
Speaker 1: this stuff, like the discussion of evanescent waves, but while
Speaker 1: those make me wake up inside, they are also super
Speaker 1: tricky to explain without visual aids. The important thing for
Speaker 1: us to remember is that if there is a probability
Speaker 1: that something will happen, if you have enough instances, you
Speaker 1: will eventually encounter that. And if that something means an
Speaker 1: electron suddenly appears on the opposite side of a barrier
Speaker 1: where it's not supposed to be, you gotta deal with that.
Speaker 1: So what this means for us in practical terms is
Speaker 1: that if we build stuff down at the nanoscale, we
Speaker 1: have to worry about things like quantum tunneling. So imagine
Speaker 1: you've got an electric circuit with all the components small
Speaker 1: enough that the wave function of the electron means that
Speaker 1: sometimes the electron can be on the other side of
Speaker 1: gates or even in a totally different wire. Well that
Speaker 1: those gates and those wires are meant to control the
Speaker 1: flow of electrons. That's what circuits are. Circuits really are
Speaker 1: controlled pathways for electrical signals, and the important part there
Speaker 1: is the control. If it's uncontrolled, you might as well
Speaker 1: not even have a circuit. So if electrons can just
Speaker 1: appear on the other side of gates as if those
Speaker 1: gates were open, or jump from one wire to the next,
Speaker 1: you've got a problem. You can't actually control electricity in
Speaker 1: a reliable way, you'll start to get errors. Now this
Speaker 1: is something microchip manufacturers actually have to deal with today
Speaker 1: because they keep scaling down. The components on their chips
Speaker 1: were happidly in the five nanometer range at this point,
Speaker 1: which is smaller than I ever thought we would ever
Speaker 1: be able to go, and their talks about possibly getting
Speaker 1: as low as three nanometers or beyond. But we really
Speaker 1: have to answer some big questions about fundamental quantum mechanics
Speaker 1: problems in order to get there. So what the heck
Speaker 1: does this mean if we were to blow it out
Speaker 1: to macro scale. Well, in our example with the toy car,
Speaker 1: it would mean that sometimes, let's just say you give
Speaker 1: the toy car a gentle push, most of the time
Speaker 1: it would just go a little bit up the ramp
Speaker 1: and then roll right back down. However, once in a
Speaker 1: blue moon, you would give it that tiny little tap
Speaker 1: and it would launch itself over the ramp. Other times
Speaker 1: you might give it a tiny little tap and it
Speaker 1: might actually move backward. Most of the time you would
Speaker 1: just see it hit the ramp and roll back. That
Speaker 1: is a challenge. If you're building out a system that
Speaker 1: relies on predictability, and it turns out that your results
Speaker 1: are not always predictable, you've got an issue. Feineman's talk
Speaker 1: did not actually spark some sort of explosive interest in nanotechnology.
Speaker 1: It would take several decades before people would really go
Speaker 1: back to it as a sort of touchstone for the
Speaker 1: whole discipline. But other developments would play a part as well.
Speaker 1: For example, in Gordon Moore's paper about quote cramming more
Speaker 1: components onto integrated circuits in the quote would serve as
Speaker 1: the basis for what we now call Moore's law. Gordy
Speaker 1: saw that the general trend was that a combination of
Speaker 1: factors can tribute to the doubling of components onto a
Speaker 1: square inch of silicon wafer every two years. So if
Speaker 1: you could fit five thousand components on a square inch
Speaker 1: of silicon in nineteen sixty five, for example, by nineteen
Speaker 1: sixty seven, you could fit ten thousand components on that
Speaker 1: same square inch. His observations take into account not just
Speaker 1: technological advancements, but also the economic drivers. And if you've
Speaker 1: never gone through the paper, I highly recommend you check
Speaker 1: it out. The article is worth a read. You can
Speaker 1: find it online for free. We typically dumb it all
Speaker 1: down these days to say that computers double in processing
Speaker 1: power every two years or so. But that's only a
Speaker 1: slice of what Moore was talking about. But how do
Speaker 1: we do this in the first place? How do we
Speaker 1: make machines twice as powerful so regularly? Well, a lot
Speaker 1: of stuff goes into it, But two really big factors
Speaker 1: are circuit architecture, that is, how designers lay out the
Speaker 1: components of a circuit, and the size of the components themselves. Intel,
Speaker 1: which More co founded, has a design philosophy called tick
Speaker 1: talk that lays us out fairly well. In the tike phase,
Speaker 1: engineers figure out how to make smaller components from the
Speaker 1: predecessor generation microchip, but using the same architecture of that predecessor.
Speaker 1: So let's say you join Intel, They're just now going
Speaker 1: into the tick phase of a processor. The previous processor
Speaker 1: was processor number twelve, So your job is to make
Speaker 1: processor number thirteen, and you're taking the architecture of twelve
Speaker 1: and you're essentially copying it, but you're making everything smaller,
Speaker 1: so you're able to fit more components on the same chip,
Speaker 1: but it's following the same general layout as Chip number twelve.
Speaker 1: In the talk phase, designers optimize the architecture for these
Speaker 1: new smaller components so that they work as efficiently as possible.
Speaker 1: So with chip number fourteen, you take the size of
Speaker 1: the components you made for thirteen, but you lay them
Speaker 1: out in a new way so that they work as
Speaker 1: best as possible. When it comes to the next tick phase,
Speaker 1: it all starts over again. So Chip number fifteen is
Speaker 1: going to have the exact same architecture as fourteen, but
Speaker 1: with even smaller components. Tick talk, tick talk. It's all
Speaker 1: about maniaturize, optimized, over and over until you hit some
Speaker 1: sort of fundamental barrier in physics that you are unable
Speaker 1: to work around. And we are headed towards that, but
Speaker 1: we keep on predicting the end of Moore's law and
Speaker 1: we haven't quite hit it. Yet, although you could argue
Speaker 1: that the length of time required has expanded over the years.
Speaker 1: But yeah, so far we have not hit that fundamental
Speaker 1: limit in physics, and we now have microchips that have
Speaker 1: nodes or components that measure in the single digits of nanometers.
Speaker 1: But eventually we will hit that limit, and we'll have
Speaker 1: to come up with other ways to keep up with
Speaker 1: Moore's law or the spirit of Moore's law, or we'll
Speaker 1: finally have to admit that we've reached the limits of
Speaker 1: keeping up with that pace and we'll have to settle
Speaker 1: for a less impressive rate of progress. No matter what,
Speaker 1: we're going to be looking at a different approach to computing,
Speaker 1: or things are really gonna plateau. Now we're going to
Speaker 1: skip ahead to the nineteen eighties because that's when we
Speaker 1: got the development of a technology that really let us
Speaker 1: get a look at stuff that was down on the
Speaker 1: atomic level. The electron microscopes had allowed us to resolve
Speaker 1: samples down to the nanoscale, but we couldn't quite do
Speaker 1: that on the atomic scale. Now atoms are less than
Speaker 1: one nanometer in size. But our abilities got a big
Speaker 1: boost in one when Gerd Binnig and Heinrich Roarer developed
Speaker 1: what is called a scanning tunneling microscope. This microscope uses
Speaker 1: a metal wire that comes to an insanely sharp point
Speaker 1: and it scans above the surface of a sample. The
Speaker 1: microscope applies an electric voltage to either the tip or
Speaker 1: the sample depends on the microscope, and what follows is
Speaker 1: a really complicated process, involving quantum mechanics, primarily the tunneling
Speaker 1: effect I mentioned earlier, and the piece of electric effect
Speaker 1: as well, and it gets way more complicated than I
Speaker 1: can adequately explain or even understand. So rather than stumble
Speaker 1: through an explanation and likely getting a lot of stuff
Speaker 1: wrong along the way, I think it's just important that
Speaker 1: we understand. Using this process made it possible to image
Speaker 1: individual atoms for the first time. This was a monumental achievement,
Speaker 1: so much so that Bennig and Roarer would get a
Speaker 1: Nobel Prize for their work in the field just a
Speaker 1: few years later. Imaging atoms brought us a step closer
Speaker 1: to being able to manipulate individual atoms, but to do
Speaker 1: that it would take nearly a decade. It was a
Speaker 1: night nine when Reese searchers at IBM found that if
Speaker 1: they worked in very low temperatures, and they used a
Speaker 1: scanning tunneling microscope. They cannot just image the surface of
Speaker 1: a sample. They could actually maneuver single atoms into a
Speaker 1: specific place. The researchers used atoms of the element zenon,
Speaker 1: and they use the incredibly precise controls of this microscope
Speaker 1: to move the atoms so that they spelled out the
Speaker 1: letters I, B, M. Cute. Huh. They use thirty five
Speaker 1: atoms to do it. And think about this for a second.
Speaker 1: So let's let's imagine just a speck of dust, which
Speaker 1: is really tiny, right. That might measure just five microns across,
Speaker 1: and a micron is one millionth of a meter. But
Speaker 1: that tiny piece of dust is itself composed of hundreds
Speaker 1: of quadrillions of atoms. I remember it. Atom is smaller
Speaker 1: than a nanometer, and a nanometer is one billionth of
Speaker 1: a me er. So when we talk about moving individual
Speaker 1: atoms around without disturbing the other atoms, it's at a
Speaker 1: level of precision that is impossible for me to imagine.
Speaker 1: I just can't work out how small that is. Between
Speaker 1: the invention of the scanning tunneling microscope and IBM S
Speaker 1: novel use of the technology to spell out its own name.
Speaker 1: We get another innovation smack dab between the two. In
Speaker 1: nineteen eighties six, Christoph Gerber and Calvin Quait invented the
Speaker 1: atomic force microscope. I mentioned that earlier in the episode.
Speaker 1: This thing can image atomic sized particles in three dimensions,
Speaker 1: and it involves reflecting a laser off the end of
Speaker 1: a cantilever with a sharp point at the end of it.
Speaker 1: As this moves across the surface of a sample, the
Speaker 1: attractive and repulsive forces acting on the cantilever change its
Speaker 1: position and angle relative to the laser, so that the
Speaker 1: laser reflecting off of it hits different parts of a sensor,
Speaker 1: and by interpreting that data, we can construct a three
Speaker 1: dimensional image of the sample. This might be hard for
Speaker 1: you to imagine. So let's say it's nighttime and you're
Speaker 1: holding a flashlight so that from your perspective, it's pointed
Speaker 1: straight up into the sky. You're making a vertical line
Speaker 1: of light straight up, and you're walking and as you're
Speaker 1: walking along, you hit the gentle slope of a hill,
Speaker 1: so you start climbing. Your feet are still flat on
Speaker 1: the ground with respect to your position. A person standing
Speaker 1: far away can't see you, it's too dark, but they
Speaker 1: can see the beam of your flashlight, and they'll see
Speaker 1: as this beam of vertical light starts to tilt slightly
Speaker 1: as you hit that slope of the hill, they'll see
Speaker 1: that it's it's turning a little bits, changing orientation. The
Speaker 1: steeper the slope you're walking on, assuming you can maintain
Speaker 1: flat feet on the ground, the greater deviation the person
Speaker 1: will see in that vertical line. Atomic force microscopes are
Speaker 1: kind of doing the same thing, but down on the
Speaker 1: atomic level. They're measuring how this reflected light is changing
Speaker 1: orientation based upon this very very sharp point moving across
Speaker 1: this tiny sample. Now, when we come back, i'll talk
Speaker 1: about some of the disciplines involved with nanotechnology. Today. I
Speaker 1: left off talking about the atomic force microscope that was
Speaker 1: developed back in nine six. That same year, Eric Drexler's
Speaker 1: book Engines of Creation The Coming Era of Nanotechnology published. Now,
Speaker 1: this was the book that really brought Feynman's nineteen fifty
Speaker 1: nine presentation out of obscurity and then built upon it.
Speaker 1: This is the reason why nanotechnology has sort of the
Speaker 1: narrative around it. It's largely due to Drexler's work. So
Speaker 1: in this book, Drexler expanded upon Feineman's ideas, going so
Speaker 1: far as to suggest we would be able to create
Speaker 1: universal assembler. And now we finally can explain what that's
Speaker 1: all about. So a universal assembler would be a device
Speaker 1: capable of building stuff out of individual atoms or molecules,
Speaker 1: and you could use these things to synthesize specific molecules
Speaker 1: through physics instead of chemistry. Moreover, with enough assemblers, you
Speaker 1: could build macro sized objects, stuff that we could actually
Speaker 1: interact with in our own worlds. But then you think,
Speaker 1: if a speck of dust has a few hundred quadrillion
Speaker 1: atoms in it, how long would it take a universal
Speaker 1: assembler to make anything we would even be able to see. Well,
Speaker 1: one thing that could speed up this process would be
Speaker 1: to have universal assemblers that could build more universal assemblers
Speaker 1: out of basic atoms. So the assemblers just start replicating
Speaker 1: themselves over and over. So you start off with two,
Speaker 1: and you get four, and then you have eight and
Speaker 1: sixteen and thirty two, et cetera. That exponential growth means
Speaker 1: that pretty soon you've got an enormous number of assemblers
Speaker 1: all over the place, and collectively, you would think they'd
Speaker 1: be able to construct stuff much more quickly. If they
Speaker 1: had a collective and coordinated a way of building stuff,
Speaker 1: then you could produce things very fast. It's like having
Speaker 1: a three D printer that can make anything out of
Speaker 1: pretty much anything. Drexler also proposed a potential doomsday scenario
Speaker 1: based on this idea, and it's the so called gray
Speaker 1: Goose scenario. The idea is that universal assemblers would malfunction
Speaker 1: in some way so that they just keep making replicas
Speaker 1: of themselves. They're making more universal assemblers, which then make
Speaker 1: more universal assemblers, and it starts to break down all
Speaker 1: other matter just to get the raw materials needed to
Speaker 1: make more universal assemblers, and the process gets faster as
Speaker 1: it goes on because you've got more of them. These
Speaker 1: tiny machines would disassemble anything that wasn't a universal assembler itself,
Speaker 1: and the creation we made would devour us all. For
Speaker 1: the time being, this is purely a thought experiment. We
Speaker 1: are nowhere close to actually making something like this, so
Speaker 1: don't lose any sleep over it. And certain aspects of
Speaker 1: nanotechnology are older than others. For example, we've been making
Speaker 1: mixtures from nanoparticles of certain metals for a really long while.
Speaker 1: As I mentioned earlier in this episode, colloidal silver is
Speaker 1: a really great example. The word colloid comes from chemistry.
Speaker 1: It's a mixture that has very very tiny particles of
Speaker 1: something suspended throughout some other substance. This isn't that different
Speaker 1: from the glass I talked about at the beginning of
Speaker 1: the episode. So silver has antibacterial properties. This is just
Speaker 1: true of that material. Even before humans really knew what
Speaker 1: bacteria were or that they were a thing, they developed
Speaker 1: a general understanding that silver could help ward off stuff
Speaker 1: like infection. Maybe that's why silver also plays a part
Speaker 1: in certain mythologies, such as the idea that you can
Speaker 1: kill a werewolf with silver or some vampire. Our legends
Speaker 1: involved using silver to kill vampires might be the idea
Speaker 1: that silver wards off impurities as it were. Today, companies
Speaker 1: manufacture bandages and wound dressings with silver nano particles woven
Speaker 1: into them to help with healing and to prevent infection.
Speaker 1: Of course, people can take the antibacterial properties of silver
Speaker 1: to extremes. There are folks who have taken courses of
Speaker 1: colloidal silver to treat all sorts of ailments, and this
Speaker 1: can have a particularly noticeable side effect because it can
Speaker 1: turn the skin a sort of bluish color. Silver compounds
Speaker 1: will build up in human cells and this is what
Speaker 1: causes that change in color. There's even a term for
Speaker 1: this condition, argeria. Take a look online for colloidal silver
Speaker 1: and blue skin and you're gonna see some interesting images.
Speaker 1: And I think that's one thing we have to take
Speaker 1: away from the young discipline of nanotechnology. We're still learning
Speaker 1: how stuff works at this scale. If you listen to
Speaker 1: the smart Talks episode I did in which I spoke
Speaker 1: with Dave Turrek of IBM, you heard him talk about
Speaker 1: using high performance computing systems to simulate molecular interactions, all
Speaker 1: with the goal of figuring out treatments for COVID nineteen. Now,
Speaker 1: there are processes that we don't fully understand happening, and
Speaker 1: not just small scales in terms of physical size, but
Speaker 1: also at small time scales. So we humans we measure
Speaker 1: time in seconds, minutes, and hours, but when you're talking
Speaker 1: about atomic and molecular interactions, you might need to look
Speaker 1: at changes that happen over the course of a few
Speaker 1: fempto seconds, and a fempto second is one quadrillionth of
Speaker 1: a second. We've got a lot to learn when it
Speaker 1: comes to the nano scale. Some materials have radically different
Speaker 1: properties when you look at them on the nano scale,
Speaker 1: properties like electrical conductivity, or the materials melting point, or
Speaker 1: it's reactivity, it's chemical react ativity, it's fluorescence, uh, it's
Speaker 1: magnetic permeability. All of those can be very different. It's
Speaker 1: almost like a substance changes identities once you get it
Speaker 1: down to that size. Another one is toxicity. Toxicity is
Speaker 1: another quality we have to take into consideration. It may
Speaker 1: be that something is completely harmless on the macro scale,
Speaker 1: like we would never have any problems if we came
Speaker 1: into contact with it classically, but if we encounter nanoparticles,
Speaker 1: those might interact with ourselves in such a way as
Speaker 1: to be toxic. So we have to really research this
Speaker 1: before we start making practical applications of nanotechnology, particularly in
Speaker 1: the medical field. We're still years, if not decades, or
Speaker 1: maybe centuries away from building nanoscale assemblers, but we're taking
Speaker 1: advantage of stuff on the nanoscale all the time. For example,
Speaker 1: you've probably heard about carbon nanotubes, a truly interesting material
Speaker 1: that we have in fact made without knowing it for centuries.
Speaker 1: This stuff helps illustrate how different things can be on
Speaker 1: the nanoscale, though I guess again we shouldn't be surprised.
Speaker 1: So carbon is plentiful stuff, and it can take lots
Speaker 1: of different forms. The two examples that you always hear
Speaker 1: about are it's the stuff that's in pencil lead, and
Speaker 1: it's also the stuff that's inside diamonds. The arrangement of
Speaker 1: carbon atoms determines the properties of the stuff at macro scale.
Speaker 1: But it sure does seem wild to think that the
Speaker 1: same thing that's soft enough to serve as a way
Speaker 1: to write stuff down on paper can also be an
Speaker 1: incredibly hard substance capable of cutting through lots of other
Speaker 1: stuff just by rearranging the way the atoms bind with
Speaker 1: each other. So what's the carbon nanotube. Well, you can
Speaker 1: start off with a sheet of carbon atoms just one
Speaker 1: atom thick, So think of it as a very thin
Speaker 1: blanket made up of carbon atoms that are linked together
Speaker 1: in a hexagonal pattern. We call this graphene. Now you
Speaker 1: roll up this graphing into a tube and you get
Speaker 1: yourself a carbon nanotube. But here's a really cool part.
Speaker 1: The direction in which you roll this material determines the
Speaker 1: properties of the tube. So again, think of it like
Speaker 1: a blanket. If you were to roll it from top
Speaker 1: to bottom, you would get one set of properties, but
Speaker 1: if you were to roll it on the diagonal, it
Speaker 1: would be a different set of properties. So carbon nanotubes
Speaker 1: can be really strong but extremely light weight, So a
Speaker 1: lot of folks hope that it could be the secret
Speaker 1: to some really phenomenal technology in the future. For example,
Speaker 1: in the space industry, getting a really high strength, low
Speaker 1: weight material is incredibly helpful. You needed to be strong
Speaker 1: enough to withstand, you know, the rigors of launching stuff
Speaker 1: into space, and you also have to remember this space
Speaker 1: is always, always, always trying to kill you. But you
Speaker 1: also want the material to be really light weight because
Speaker 1: that reduces the amount of energy you need to get
Speaker 1: the darn stuff off Earth in the first place. Carbon
Speaker 1: nanotubes have been suggested as a possible material for a
Speaker 1: tether for a space elevator. The space elevator concept is
Speaker 1: kind of trippy. Essentially, you've got a weight or technically
Speaker 1: a counterweight, like maybe a space station, and it's out
Speaker 1: in space and it's tethered to the Earth that has
Speaker 1: anchored somewhere along the equator of the Earth, and this
Speaker 1: counterweight the space station would be way out beyond geo
Speaker 1: stationary orbit. That is, way the heck out there. Geo
Speaker 1: stationary orbit is around thirty six thousand kilometers the the
Speaker 1: International Space Station is just at four hundred eight kilometers,
Speaker 1: so we're really talking deep out there. But the idea
Speaker 1: is that the centrifugal force on the tether would be
Speaker 1: equaled by the gravitational pull on the tether, and you
Speaker 1: would end up with a taught cable that could go
Speaker 1: up to the stars or at least out into a
Speaker 1: far orbit, and an elevator would be able to climb
Speaker 1: that cable, delivering payloads out into space without ever having
Speaker 1: to load it onto a rocket and blast the stuff
Speaker 1: up there. Now, there are a lot of engineering challenges
Speaker 1: in the way of ever realizing this technology here on Earth,
Speaker 1: among them finding material strong enough to with stay and
Speaker 1: the crazy amount of force it would be under. Some
Speaker 1: folks hope that carbon nanotubes could be the answer to that.
Speaker 1: That's just one tiny example pun intended of a possible
Speaker 1: application for nanotechnology, but one that's really still far off
Speaker 1: in the future. If it's a you know, at all
Speaker 1: a possibility, but In the meantime, countless scientists are learning
Speaker 1: more about what happens on the very small scale, which
Speaker 1: is great because it extends our knowledge about how the
Speaker 1: universe works, and it also gives us the opportunity to
Speaker 1: leverage that knowledge and fields like chemistry, medicine, material science,
Speaker 1: and robotics. Nanotechnology plays an important role, just not one
Speaker 1: in which we have very teeny tiny robots building stuff
Speaker 1: atom by atom. We have done some molecular manipulation on
Speaker 1: that scale, but it's been far more meticulous and human
Speaker 1: controlled than the sci Fi scenario. Now, all of this
Speaker 1: is to say that a lot of the technologies that
Speaker 1: are marketed as nanotech are at best mis leading. I've
Speaker 1: seen robots that have been called nano robots, and they're
Speaker 1: pretty small, but they're not even crossing the micron threshold,
Speaker 1: let alone the nano scale, so I think that's not
Speaker 1: really terribly accurate. There have been some interesting sensors and
Speaker 1: switches and things that are on the nano scale that
Speaker 1: you could argue fit into nano robotics, although it doesn't
Speaker 1: necessarily match what we classically think of as a robot,
Speaker 1: but it's still closer at least than these small but
Speaker 1: not you know, microscopic robots that I see marketed as
Speaker 1: nanobots all the time. I'm sure I'm gonna do a
Speaker 1: lot more episodes about nanotechnology, including specific implementations. I mean,
Speaker 1: I didn't even get into Bucky balls in this episode,
Speaker 1: so you know, I've got to come back to it
Speaker 1: in the meantime. If you have suggestions for future episodes
Speaker 1: of tech Stuff, whether it's a specific technology, a company,
Speaker 1: a person in tech, maybe just a trend, let me know.
Speaker 1: Reach out to me on Twitter or Facebook the handle
Speaker 1: for both of those as text Stuff H s W
Speaker 1: and I'll talk to you again really soon. Y. Text
Speaker 1: Stuff is an I Heart Radio production. For more podcasts
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