TechStuff Classic: Say My Name

But seriously, we wanted to talk about Heisenberg. Heisenberg's work in theoretical physics and how that made a huge impact and continues to make a huge impact in technology. So sit back, relax, and enjoy this classic episode of tech Stuff. I'm just not sure about this topic. Heisenberg, right, okay, wall I think I have some notes on him too, are you? This is he was born on December five, nineteen o one. Yes, that one, the physicist. Yes, the

famous theoretical physicist. All right, well, all right, maybe I won't get a geek out about breaking bad, but that's fine. We can talk about Vernon Heisenberg. I like that your German pronunciation is better than the lady with the last name vocal bomb. That's pretty that's pretty great. Um. So born on December five, nineteen o one, in Verzberg. Uh and yeah, Heisenberg has played an incredibly important role in the establishment that that's the foundations of what is quantum mechanics. Right.

If you've heard of something something called the uncertainty principle, that is a k A. Heisenberg's n certain new principle, that that is, he is the operative Heisenberg. In this we will explain what that uncertainty principle is in certain terms, but that'll be towards the second half of the podcast. First we wanted to kind of talk about who he was, sort of his background. His father was an expert in Middle and modern Greek languages. That's a Dr. August Heisenberg.

His mother was any Winklin. Winklin Winklin was w. Yes, there's no W sound in German. It's um. Yeah, so vs, r F S and w s or vs. That's easy to remember, simple, all right, Yeah, so yeah, he he um. It's funny because I understand that his his own background

in Greek, his father was an expert in Greek. His own background in Greek meant that when they got to the point where physicists were starting to name theoretical and he would correct people's use of Greek, saying things like, you cannot spell it this way because that's not how it would be actually spelled if such a thing existed in the Greek language. So so he was, um, you know, helping us stay on the rails as far as the

use of Greek, right while he was growing up. When he was twelve, that is when Neil's Bore present did his general theory of of quantum existence. Yes, so Bore would be incredibly important during Heisenberg's education. But Niels Bore also known for making the Bore model of the atom. So that was the model the atom that suggested that you had a central nucleus and then electrons that were

orbiting nucleus. Yeah, so that's you know, anyone who's taken any any class in chemistry or physics has seen the Boor model. It's still one of those things that um usually is. It's part of the history of the development of particle physics and quantum mechanics. Right, we we know now that it's a little bit um simplified. Yeah. In fact, Heisenberg would go on, would be the one who right exactly right. Uh, he was. While he was in high school, there was a major event that played out across the

entire world and particularly in Europe. World War One. Yeah, World War One happened between nineteen fourteen and nineteen eighteen. Some of Heisenberg's academic contemporaries, or not even contemporaries, some of his mentors had actually served in World War One as various officers in the military, right right. Um, Heisenberg himself had to leave school, leave high school to go

help harvest crops in Bavaria at the time. And um, by by the time he got back after the war, he was deeply involved in youth groups like the New Boy Scouts that we're trying to rebuild the science and artistic culture in Germany. Right, So keep in mind, like

at this time in Germany, things are really tumultuous. I mean, World War One was already one of those events that that played upon certain sentiments in Germany, and after the war was concluded, that got even more messy because you had the rest of the world, uh, you know, trying to deal with this situation and make sure that it

could not happen again. I mean, this was one of those wars that no one really expected whatever happened, because the idea was that everyone would be building up their armies to a point that anyone would be crazy to attack anyone else. And as it turns out, humans are crazy, y'all. So um, yeah, we it was. It was one of those things where where as in an attempt to prevent this from happening again, there were a lot of reparations

demanded against Germany. This in turn ended up fueling a lot of resentment in Germany and would eventually give the Nazi movement sort of the kind of foothold. Yeah, exactly, it gave them that that that place to build some support, because you had all these Germans who felt that uh, that their lives had been ruined as a result of the actions that followed World War One. Now that plays a big role in Heisenberg's life because this is also

a time when physicists are making incredible discoveries. We are learning more about the quantum world, that that atomic scale world than ever before. The instruments that were being made were becoming precise enough for us to look at things on a level that we never could have seen before. So there is a figurative explosion in physics at this time, and a lot of and sometimes literal explosions. But a lot of the physicists that were active at this time,

particularly in Germany, were of Jewish descent. Now, of course that would cause play another important role once we talk about the rise of the Nazi movement and the entry into World War two. Obviously that's going to to really shake things up. But before we get to that point, we talk more a little about about Heisenberg's educational background. Once World War One had concluded, he attended the Maximilian School at Munich and then eventually the University of Munich.

He originally went to study math, but according to reports, a professor wouldn't let him into an advanced seminar, and that's when he switched to physics. And just imagine what the world would be like without the I mean, quantum physics, for example, might have a very different approach, particularly when you start talking about people like Schrodinger, and we will and maybe we'll even mention his cat so uh. He at the university, he studied physics with professors like Arnold

Johannes Wilhelm Sommerfeld, who was a theoretical physicist. Uh he was a physicist who would stay on teaching even during World War Two, so he stayed in Germany and continued to teach. He did get a little upset that the more than a little upset that his departments were being completely yet purged of anyone who had any sort of Jewish background, whether they self identified as Jewish or if they had maybe an ancestor the three generations back who

was Jewish. Sure. Also, according to some reports, the Nazis considered the theoretical physics as a field to be Jewish. Yes, yes, because there were there were so many Jewish thinkers who were the leaders of theoretical physics that the Nazis looked down upon the entire discipline as being something that was

impure and should be completely purged. And in fact, instead they wanted to have Deutsche physique that's German physics as a study as opposed to theoretical physics, so that would also disrupt the advances that could have happened during that time. Another professor was Wilhelm Karl Ferner Otto, Fritz Franvien. You're just enjoying saying these names, aren't you. Wil Helm veen Is usually how we we say that, but yes, you're The answer to that question is yes, I love I

love saying German names. Uh. He was a physicist and he focused on black body radiation and electromagnetics magnetism rather and he passed away in so he died before World War two began. He died before the Nazis had really taken control of Germany. Um there was Alfred Pringsheim who was a professor of mathematics and had Jewish roots. During the Nazi regime, he would see his entire fortune taken from him. Everything he had inherited a huge fortune and

everything he owned was taken by the Nazis. He was eventually forced to change his name to Alfred Israel Prinsheim because of his Jewish ancestry. One wonderfully racist, you know, the Nazis were not known for being subtle with the way that they treated any one of Jewish heritage. And then a fourth professor was Arthur Rosenthal, who had a focus on geometry as well as dynamical systems, also had

Jewish roots. He would be forced from his position in nineteen thirty six by the Nazis and would eventually immigrate to the United States and nineteen nine and taught at the University of Michigan, which has come up a lot in our conversations recently because that's where Sid went to. But he taught the University of Michigan, then eventually taught at the University of New Mexico and then later at

Purdue University. So these were the four professors who really kind of sparked Heisenberg's fascination with physics and mathematics, and this is founding in in those subjects exactly, So Somerfeld, Veen, Pringsheim,

and Rosenthal Uh. Then in nineteen two Heisenberg went to Goodingen Goodingen as a University of Goodingen to study physics under some more famous physicists, including Max Bourne, whose focus was on quantum mechanics, particularly in statistical interpretation of the wave functioned, which we will talk about again and a little bit because Schrodinger was definitely a wave functioned guy. As it turns out, Heisenberg was different. He did not

really look at the wave function of quantum physics. He was looking at something else. And now I'll explain that when we get there, because that's fun for me. Um. The born Max Boorne was also the director of theoretical physics at the university and was Jewish, so he immigrated to the United Kingdom when the Nazis came into power in Germany and continued to research particle physics, well well not quite particle physics, quantum physics, and theoretical physics, as

well as teaching in the UK. Then you had James Frank, who was a physicistant, studied atomic and subatomic collisions, particularly electrons colliding with adams, and also was of Jewish heritage. So he would leave Germany in nineteen thirty three for the United States and would later participate in what was known as the Manhattan Project. We could do a full episode on the Manhattan Project that in fact. Yeah, it's an amazing story. Um. And here's another great story with

James Frank. So he won the Nobel Prize in n for physics. He left the gold medal, the Nobel Prize medal back in Germany when he left to essentially flee to the United States. Um. There was another physicist named George de Heavasy. And I know I'm saying that name wrong,

so I greatly apologize. But for once, we're talking about someone who's not German, so I can't say his name, but he he in order to protect this gold medal from being taken by the Nazis and melted down, he dissolved the metal and acid and then put the solution on a shelf, so it's a solution with dissolved gold on the shelf. World War two is over, he goes back,

the solution is still on the shelf. He then precipitates that solution, precipitating the gold out of the acid, and he used the gold to melt it back into the metal and meant a new and meant a new metal so that they can give it uh back to James Frank.

So that I thought was a really cool story. Then there's another professor he studied under was David Hilbert was a mathematician who focused on geometry and functional analysis who retired in n so he lived to see the Nazis purge Germany of Jewish mathematicians and physicists, and was later asked at a state dinner. He was actually asked a question about what was the state of mathematics after it had been quote unquote free of Jewish influence, and his

response was, there's no study of mathematics anymore. He was essentially saying that the actions of the Nazis had effectively into the entire field because they had they had removed or or had caused to flee all of the leading thinkers and instead, including like Einstein. So they were turning mathematics and science into a political thing, and by doing that, they were saying that these other things that did not

fit that political regime as invalid. And that's not the way science works, not the way mathematics works, but that's how we're demanding it. It can be a very effective means of controlling a population by controlling their education. Sure, but also it also ends up meaning that you really you, you just throw a huge monkey wrench into any kind

of advancement in those fields. So before World War two, this is this is all happening before World War two, and Heisenberg is studying under these different professors, so during these years he has the ability to really pursue his interests in theoretical physics and mathematics. So, uh, this was on the in the nineteen twenties, and so it was before even the Third Wreck was coming into power at all, right, Right, So that these are in the years between World War

One and the Nazis rise to power. So during those years,

that's when Heisenberg was studying. And while many of his professors would end up having to flee or would be removed from their jobs, at this time none of that was necessarily evident that that was going to happen, So he spent his time really talking with some of the leading thinkers of the day when it comes to theoretical physics and mathematics, right um so Ine he earned his PhD from the University of Munich and um went to become an assistant to his old professor Maxi Born at

the University of getting In and so in four he would go to the University of Copenhagen and begin work with Niels Henrik David Bore, who was Danish, not German, but a Danish physicist and uh and of course he was really interested in atomic radiation and atomic structure, and we talked about the Boor model of the atom earlier in the podcast um so. In nineteen six Heisenberg would go to the University of Copenhagen for about a year

and then leave. But in ninety six there was a position opening opening up at the University of Copenhagen for a lecturer in theoretical physics. So Boor recommended Heisenberg, thinking that Heisenberg was an up and coming leader in this space, and so Heisenberg became the lecturer and theoretical physics at the University of Copenhagen. Bore himself would be at Copenhagen for quite some time until nineteen forty three, where he would eventually flee to Sweden to escape the Nazis. Nineteen five,

that's when Heisenberg publishes his theory of quantum mechanics. So he was of the ripe old age of twin d three years old, twenty three years old, and he is uh, he is he is presenting a completely um well, he's presenting his own, his own perspective on what quantum mechanics actually is. As we'll see, that ends up getting kind of assimilated into a unified view by looking at some some other theories that Heisenberg did not necessarily agree with

at the time. Nope, not so much at all. As it turns out, physicists, like any other type of human being, can occasionally get very married to specific ideas and maybe a little bit snarky. Yeah, there's some there's some great

quotes that will be reading. Yeah, but yeah, it turns out that not everybody agreed on the behavior of particles at that level because they were first of all, there was no way to really directly observe them, so it's all hypothetical, and it was mostly things like your equations are are not as easy to understand my equations, therefore my equations are better. That kind of thing. In fact, that really is one of the arguments. So in n seven, at the age of twenty six, you know, he's he's

definitely hitting that that middle age there for physicists. Twenty six years old, he becomes the professor of theoretical physics at the University of Leipsig and this made him the youngest full professor in Germany at the time. Yeah, so he was certainly making a name for himself in the

in the academic world. In nineteen nine he goes on a lecture tour of the United States and Japan and India, uh and in nineteen thirty two he received the Nobel Prize in Physics for his discovery of the allotropic forms of hydrogen. It was is for from that paper that he had published about quantum mechanics. Out of that, one of the applications was this discovery. Right. So, in case you're wondering what the heck is an allotrope, it's a

different structural modification of an element. So let's take carbon. Carbon is a great example. When you have a certain structure of carbon, it forms graphite. Different structure of carbon forms diamond too, slightly different substances. Yeah, these these different these different manifestations of the same element. I mean, it's it's the exact same element, it's just the way that it's been or the way that it arranges itself determines its qualities. And graphite and diamond are like nine day

they're incredibly different. So that's what an allotrope is is these different manifestations of an element that have very different qualities. With the case of hydrogen, we're talking about ortho hydrogen and parahydrogen. Don't ask me what that actually means, because I'm not a physicist or a chemist, so I am incapable of answering me neither. I am. I'm at a loss there, but I do know that In ninety seven, Heisenberg married Elizabeth Schumacher, who he would go on to

have seven children with over the course of their marriage. Wow. Now this is also the time when we're starting to see the Nazis come into power in World War Two is beginning, uh, and this was this becomes a pretty muddy area of Heisenberg's life because it's hard to know

which historical records are the most accurate. Right, There's there's a lot of contention within the historical community about um what exactly Heisenberg's personal views and u and roles were in In all of this, he had become the target of of Johannes Stark. Na, I'm just er apologize our English. Our English pronunciation in German pronunciation are different and and and to be fair, the vocal downside of my family

is is really more like Polish Russian. So Johannes Stark was also a physicist, but he was and he was a physicist in fact, who in his UH in the twenties had published a paper by Einstein. He had act um Uh solicited Einstein to write a paper for the publication that he was editing, and it was a publication that would eventually lead Einstein to ruminate upon the general

theory of relativity. It was sort of a kind of a precursor to his general theory, which meant that in a way, Johannes Stark was very much part of what made Einstein a worldwide phenomenon. Now, the reason why I say that's really interesting, or perhaps he might even say ironic, is that Johannes Stark would align himself with the Nazi regime. He wanted essentially to be the fewer of physics, which is that's I mean, that's exactly the way I saw it worded when I was reading the biography, which is

kind of terrifying. But he he also aligned himself with the Deutsche Physics movement, the the German physics movement, and he said that because Heisenberg continued to teach Einstein's theories and the classroom in Einstein's theories, of course we're not part of this Deutsche physics, uh movement, that he was what what Stark would call a white Jew or an arian Jew, someone who is not Jewish by heritage, but is by association, because he continues to teach these thoughts

that Jewish mathematicians and physicists had come up with, so that somehow that meant that he was a traitor. Yes, so, um So Stark was very much opposed to Heisenberg and didn't feel that Heisenberg should should have any sort of position of authority. That did not stop Heisenberg from having that position. He was obviously very important to the university

and was one of the few protected. Of course, part of it was that he did not actually have any Jewish ancestry that anyone could determine, so that kept him somewhat safe, right sure, um you know, there's part of the debate about Heisenberg is whether or not he um he stayed in order to uh to help preserve Germany's scientific and cultural communities, or whether he was actually working

for the Nazi Party. Um he he was made the director of the German Adam bomb project and spent about five years working on that, supposedly, during which another portion of the debate is whether he was working towards a nuclear reactor or nuclear weapons, and no one is really

entirely sure. Supposedly he gave a report to Nazi official Albert spear Um that as of one or so, it would take three or four years for them to build a nuclear weapon and that that is part of why the Nazi Party said, I'll forget this nuclear weapon thing, let's go with nuclear reactors to help drive Sure, um and uh so, but but you know, that's that's There's

been other research. Um. For for example, one Paul Lawrence Rose wrote an entire book called Heisenberg and the Nazi Stomic Bomb Project that stated that, uh, Heisenberg wasn't being evasive to the Nazi Party, that rather, he was being truthful due to a basic misunderstanding of the way that nuclear fission worked, and that by the time he figured it out, it was when the war was already winding down and he started to hear about the atrocities that

the Nazi Party had committed and kind of reactively recreated this image of himself as as having been an anti Nazi the entire time. And that's the thing is that it's it's impossible for us to say one way or the other because there are conflicting reports and and really it's you know, it's just it's a it's a difficult thing. Again. Once again, we take our our our podcasting hats off to our sister podcast Stuff you missed in history class that deals with this kind of stuff all the time.

Oh sure, and and especially you know, everything surrounding the Nazi Party is incredibly sticky. Um. You know, some some of my favorite favorite stories about that time or stuff like like like like Lenie Reefinstahl, who was one of the who was the propagandist or a documentary filmmaker for the Nazi Party, And I mean she she took tea with Hitler frequently and has claimed forever that she never knew about the atrocities that were going on. And so it's it's it's one of those things like who do

you believe? Yeah, and uh yeah, getting back into into the what Heisenberg was going through at this time. So there is there's an argument to be made that he was trying to preserve the scientific community in Germany as best he could, because there were others who were also trying to do that. Max Planck, for example, was also

trying to um to do that. Although Plank had hoped that the the rise of the Nazis was just a temporary kind of kerfuffle and that it wasn't going to balloon into this incredible conflict that would span the entire globe, he just had no he had no concept of that actually happening, so he had I had to stay and to try and keep the German departments of mathematics and physics as intact as possible. So it could be that

that's the case, We honestly don't know. In ninety one, Heisenberg becomes the professor of physics at the University of Berlin and the director of the kaiserville Helm Institute for Physics, and in nineteen forty five Heisenberg is taken prisoner by

American troops and is sent to England. UH. He's freed in nineteen forty six and returns to Germany and helps rebuild the Institute for Physics at Guttingen and then UH that eventually becomes the Max Planck Institute for Physics, which would eventually relocate, and I believe I believe Heisenberg personally renamed the institute them on Max Plunk. And he would continue to travel and give lectures about his work, in fact doing so almost right up to when he died.

He died in on February one, nineteen seventy six, after developing cancer, so he was very much active in the world of lectures and academia. Well after the end of World War Two. Yeah, towards the end of his life he became interested in plasma physics and a thermonuclear processes. So see, it's uh, you know, it's certainly one of

those interesting timelines. And in a moment, we're going to really dive into what his contributions were in the field of quantum mechanics and give a full explanation or as as full as we possibly can make it of what the uncertainty principle is all about, as well as why it's important in technology, because yes, this does have to do with tech. It's just going to take us a while to get there. But before we jump into that, let's take a quick break to thank our sponsor. Alright,

So now it's time to dive into quantum mechanics. I gotta tell you, I'm not really certain about this. I'm just gonna keep making that joke excellent until it's funny. Um. So, yeah, he was. Heisenberg had worked in theoretical physics and quantum mechanics during the early early days of the discipline, and he was particularly interested in studying the radiation from an atom.

But here's the thing that he was also interested in seeing what was actually observable, you know, really look at the atom and see what you could actually see it because we had all these hypothetical particles in these theoretical particles, things that that should exist based upon the math involved.

But but but the science at the time was based on on bombarding these these tiny, tiny, tiny sub atomic particles with um with things like gamma radiation and then observing what we could observe, right, And so he began to differentiate between what you could observe and what you could not, and then he started to notice things. He said that, you know, we can't really always assign a position in space to a specific electron at any given time,

and we can't follow electrons around their orbits. It's it's not like a planetary orbit that we can watch continuously, right, It's more like there's an area that an electron could be in, as opposed to we can specifically point out that this is where the electron is at any given moment, or this is the direction it is traveling at any given moment. And this would start to plant the seed

in his mind for the uncertainty principle. So first he said that, you know, bores postulation that the the the orbits of electrons are around the nucleus was more or less correct. You couldn't actually be certain of what those orbits were because the unobservable nature of these. Yeah, there's just no way to assign a figure to this. You can't say the electron is in uh, this particular quadrant around the nucleus um and you couldn't talk about really

the electron's velocity either. Velocity, by the way, is speed plus direction, right, And so he started to say that instead of using UM classic numbers, the kinds of numbers that we would use to describe human scale physics, that that we needed to use UM matrices. Yeah, and a matrix is essentially an abstract mathematical structure. So this was almost like talking about probabilities. It's it's kind of fuzzy,

it's not specific, it's not precise. And in fact, that was Heisenberg's argument, was that precision is something that you could strive for, but you were never ever going to get. Uh. He kind of arrived at this gradually. So in nine he was involved in a bit of a spat, a debate, if you will, about a theoretical spat actually was real spat about theory. Uh, but it was on. So you

had two sides to this debate. You had Heisenberg and his his fellow physicists who thought of quantum mechanics in the term of these matrix these these this abstract mathematic way of describing the position or motion of an electron, because again he was arguing that you could not define it in a way that was like it's at x, y and z coordinates. You could not do that, right,

I was using the matrix. And there was another set of scientists who were trying to describe some atomic particles as as waves the way that we would electromagnetic radiation. Uli r own Trodinger, Yeah, Schrodinger Singer and is kitty cat? Actually Schrodinger and the cat story is kind of interesting,

just a little side notes. So you've probably heard of Schrodinger's cat, where Schrodinger was, uh, kind of giving a thought experiment kind of thing to explain how how this this other form, the matrix form of quantum mechanics is a little weird. The idea that you have a cat inside a box, and inside that box you also have a little canister with poisonous gas in it. And there's some explosive that has a that that will go off at some point and I am giving a variation classic.

So so within half an hour, there's a fifty chance that the explosive inside that canstor has gone off and released the poisonous gas and little killed the cat. Yes, Kitty is no more. One life down, eight to go. There's also a fifty percent chance that the that the explosion has not yet happened, and that Kitty is fine but possibly very bored inside this box. And so the thing is that because of uh, this this weird quantum effect, and keep in mind this is really something that only

happens at the quantum level. When you get up to the macro level that we see this is not actually

the case. But the idea is that the cat is both alive and dead at the same time, and superposition that has both states and superposition, and it's only when you open up the box and observe the cat that one of those two possibilities becomes true is true, and the other one just becomes yeah, it goes away, and that then you have either the live cat or the dead cat, so that the cat is said to be alive and debt at the same time until you observe it,

and that's when reality snaps into place and you suddenly get one of the two results. And it was kind of a way of saying, like this is just, you know, kind of crazy to be one of those things we always refer to anyway. So Schroinger's cat and Heisenberg's and certainty principle both are trying to explain various weird things

about the quantum level. There's another one that we can touch on also that gets confused with Heisenberg's and certainty principle, which is the idea that by observing something you actually

affect the outcome. So, in other words, when we're looking at sub atomic particles, simply shining light onto them affects their movement because we're talking about photons impacting subatomic particles, which changes the pathway, which means just by taking an observation in a measurement, you have changed what as what was going to happen. So it makes it even more impossible to predict things based upon the behaviors of stuff, because just by observing it, you change what that outcome

actually is. Now that's not heisenberg'sun certainty principle either, but it often gets confused. So we've got this debate. We've got the wave mechanics debate, and that's Schrodinger's side, and we've got the matrices debate, and that's heisenberg side. And the debate was not always civil. Uh, there was there. There was a quote that Heisenberg made to another physicist, Wolfgang Ernst Pauli, which was, the more I think about the physical portion of Schrodinger's theory, the more repulsive I

find it what Schrodinger writes about the visualizability. Visualizability, Boy, that's a hard word. Of his theory is probably not quite right. In other words, it's crap thick burn. Yeah, that was a little that was a little rough. So here's what the difference was between these two. Schroedinger's approach required less complicated math to explain the relationship of a subotomic particles movement and and and uh, it's it's position around a nucleus, for example, an electron around the nucleus

as an example. But it furthermore explained some of the things that Heisenberg's theory couldn't really fully explain. It's sort of it's sort of pushed them under the rug in a way, because Heisenberg's approach showed that there were these little quantum jumps quantum leaps as if, yes, exactly, there's quantum leaps when you cannot quite solve the problem, or you solve the problem and then you have to leap into the next body and hopefully your next leap is

the one that takes you home. No, in this case, the quantum jumps were the fact that you would see electrons behave in a weird way, like suddenly an electron would behave as if it had a higher amount of energy than it normally would, and that was, you know, Heisenberg's approach showed these jumps well with Schroedinger's approach, because we're talking a continuous wave a wave function. It smooths everything out, so you don't have these jagged, you know jumps,

you have just a smooth transition um. So the Schrodinger's argument was that, hey, you know, I've looked at the way you are calculating this, and I look at the way I'm calculating this, and it turns out the outcomes are the same. We're getting the same results, but mine requires less complicated math and not all this mathematic abstraction that you are insisting upon. So therefore I'm right and

you're wrong, or at least mine is more eloquent. So you've got these two parties of physicists getting a little caddy schroedanjer caddy. Perhaps, um, there are alive cats and dead cats. But then, uh, it's interesting because you started getting into other physicists getting into the game, including Ernst Pascual Jordan's or Jordans I suppose, who was a German physicist who would actually later joined the Nazi Party become part of that movement, in fact enlisted in the Luftwaffe Um.

And then you had Paul de Rak who was an English physicist who both created unified equations that took the wave function approach and the matrices approach and combine them into what was called a transformation theory, which is the very basis of quantum mechanics. So again this is all theoretical.

It's essentially trying physicists trying to figure out how to to apply the same sort of observation that they had in classical interpretation of physics on the macro scale to the quantum level, which is the incredibly tiny scale, the atomic or subatomic scale at which the rules do not apply. Right. So, but the transformation theory ended up showing that there was a combination of both Schroedinger's approach and Heisenberg's approach the sort of wave particle duality that we know about with

quantum mechanics. That's kind of what was coming out of this discussion. So instead of them both saying no, I'm right, no, I'm right, these guys are like, well, actually you're both right.

Nic Yeah, light is a particle and a wave, and it gets boy, toy doesn't get even more crazy, Like it seems magical to those of us who are used to classical physics on that macro scale, because if things on the macro scale behave the same way that things in the quantum scale behaved, it would be like we were living in Harry Potter World or something right right there.

There would be a lot of a lot of you know, people suddenly jumping to the left right, yeah, because you know, or you could never really be sure where someone was or how quickly they were moving and and emitting light. When they did it, they'd be half dead and half alive until you looked at them. Yeah, there's a whole bunch of things that would be pretty bizarre in our world. Lauren and I have a bit more to say about Heisenberg in this classic episode, but before we get to that,

let's take a quick break and thank our sponsor. So, Heisenberg studied Jordan and DeRos papers and found that there were problems when ever each right to measure the basic physical variables appearing in the equations. And by physical variables, I mean an electrons position and its momentum. So that led Heisenberg to create the famous principle of uncertainty, which you did in ven. We usually call that Heisenberg's uncertainty principle.

So here's here's how it breaks down. The more precisely you determine the position of a sub atomic particle, for example, an electron around the nucleus. So the more precisely you determine its position, the less precisely you can know about the momentum at that moment, and vice versa. So if you more precisely determine the subotomic particle's momentum, the less

precisely you can know its actual position. Right, Um, So Specifically, he was saying that um that running the calculation for this, for this determination of the position and the momentum um necessarily contains errors, the product of which physically cannot be less than the quantum constant h plucks constant, which is that the smallest unit the quantum of action in an atom. Right, And so what he's saying here is that it doesn't

matter how advanced your measurement apparatus is. In fact, there was one point where More criticized Heisenberg's approach because he said that he was using essentially microscopes that were not precise enough, and in fact I made an error. And then Heisenberg got really upset a Bore, and the two of them had a falling out that lasted about a year, and then Heisenberg eventually wrote a paper and acknowledge He said, you know, Bore has criticized this because of such and such.

An acknowledged that in fact, there was an error, but said that ultimately that error was beside the point because it would not matter how precise that was, the fact remained that the more you would learn about one thing, the less you could know about the other. That's the uncertainty or complimentarianism is another way that some people have said that there's this complementary relationship between the momentum and

the position. So in case you want to know what momentum is, that's mass times velocity, velossities that speed and direction. So that's important to know. So on the human scale, this uncertainty is completely negligible. There's you might as well just throw it out the window because on our scale it just doesn't that it doesn't factor into it. It's such a tiny thing. But when you look at the smaller scales, this tiny tiny thing becomes huge because you're

looking at things on an incredibly small scale. And because we can't know but with precision both a subatomics particles a position and its momentum, we cannot really make predictions about what's going to happen in the future. And in fact, uh this is where Heisenberg says causality becomes a problem because if you cannot determine that subatomic particles position and momentum,

you cannot actually know what's going to happen next. So if you were to expand this out, now this is this is to the absurd, But if you were to expand this out, you could say that you cannot for certain know that by doing a certain action, a particular effect is going to follow. That's not really the case with classical physics again because we're talking up the macro scale,

but on the qualm scale, that's the case. We cannot really know what will happen from one moment to the next because we can't know enough about all the factors to make that determination, which is which is kind of wonderful and kind of terrifying right simultaneously, and though it's a cat in a box yep. And and then this also ties into that observation problem, right because if we even if we observe the phenomenon, then we're affecting, we're

changing the phenomens. We're making it even more impossible to determine what the effect is going to be. The cause and effect at the scale is something that becomes purely theoretical because as soon as you try and apply practical approaches to it, it all breaks down. And we promise this really does relate directly to technology. Yep, we're getting there. So we then show that light can be interpreted as

both wave functions and as a particle. That's with Boor and Heisenberg together working they were able to kind of come to this conclusion. And as soon as you decide how to observe a particular experiment, that interpretation becomes true and the their interpretation collapses. So in other words, if you're looking at light as a wave, you see it as a wave. If you look at light as a particle, you see it as a particle, and the other half

of that interpretation goes away, which is insane. They were talking about it about how how you observe the experiment, we disturb untouched nature and we become limited and learning about nature as it really is. In other words, we have a very narrow view into what reality is, and once we focus that view on something, we cannot know

everything else that's outside of that view. So imagine that you have a telescope and you are using that telescope to look at something that's on the distant horizon, and you can see that, you can see the thing that's on the horizon, but everything else has faded away. It's like all of that's just gone. That's kind of what the sort of an analogy as to what he was saying here, which is disturbing to think about in a way. But that's how reality works, so you've got to kind

of deal with it um. So Heisenberg's uncertainty principle in Shringer's wave functions become the basis of the Copenhagen interpretation

of quantum mechanics. And uh, the reason why we even did this podcast besides the fact that I think someone actually asked us to and Lauren's going to look that up, but the reason why we're doing this is because Heisenberg's uncertainty principle plays into the way that we use electronics today, because now we're working with electronics that have components that are on this tiny, tiny skin at least the nano scale, which is one one factor up from atomic but far away.

The flow of electrons is critical for modern artronics absolutely, and while we're making these tiny transistors or transistor elements that are part of these integrated circuits, you know that the whole purpose of transistors is to guide the flow of electrons to allow them to pass or to not

allow them to pass through a circuit. Well, if you make the gates really thin, then Heisenberg's and certainty principle tells us that there is a kind of a zone in which you might find an electron, and because of the uncertainty about the electron's momentum or energy, sometimes that electron can jump up an energy level because of our uncertainty.

We we you know, it just will pop up an energy level and then pop back down, which means that can be found in a slightly larger zone than you would not necessarily expect based upon its actual energy level, which can be problematic when when you've got these incredibly thin gates that are supposed to be keeping an electrons on one side, right that that zone might extend beyond

the far side of that gate. And if the zone extends beyond the far side of the gate, that means that it's possible for an electron to appear on the other side of the gate without having actually passed through

that circuit, which means called electron tunneling. And since it's possible, it happens, which which means that, yeah, unless we figure out ways of getting around these you know, these these fundamental quantum phenomena that we you know, there's a point where you cannot make the components any smaller because the electrons just won't play ball you're just gonna go every way that the fundamental quantum traffic laws, as you put

it in our exactly. Yeah, yeah, it means that that you're you're gonna get errors in your various chips because they will not be allowing the or or preventing the electrons from flowing the way they're supposed to, because the electrons are just gonna be able to tunnel right through when when those uh those energy levels bump up uncertainly.

It's bizarre, it's so weird to think about um. But engineers have found ways of working around that, using different materials that uh that that minimize this so that they can continue to make things smaller and smaller. But we will reach a point when that is just not going to be the way that chips will be designed anymore.

Either will will plateau and we won't be able to make chips with smaller components, or will find a different means of using suba comic particles to process information, and we'll move away from electron based chips, which is hard to consider. It's really weird to think about. Yeah, that's not that that that is beyond my entire brain right now. Yeah, No, I'm actually starting to feel a nosebleed coming on because

I'm a I'm an English literature major. Al Right, well, let's let's let's bring this back to something, to something a little bit more peaceful and serene. I have I have a quote from Heisenberg via via pbs um. He once said, natural science does not simply describe and explain nature. It's part of the interplay between nature and ourselves. It describes nature as exposed to our method of questioning. That's

pretty cool, which I thought was nice. I thought that that was a much less nosebleedy way of saying that that we mess stuff up scientifically. And also it also is less uh nasty than his note to U or note about Schrodinger. Right. So um oh, I found the name of the person who requested this via Facebook. This was from listener Peter. So Peter asked us about this, and I hope that we were able to answer your

questions to uh your satisfaction. It was certainly to the best of our ability, keeping in mind that neither of us are theoretical physicists or mathematicians for that matter. Uh. Fascinating subject and there are a lot of books out there that are really really good about explaining Heisenberg's role and also the contributions of his contemporaries, everyone from Einstein to Somerville to Schrodinger to Toll, all the great physicists of the nineteen twenties and thirties who have really made

modern technology possible through their discoveries. Well, guys, I hope you enjoyed this classic episode of tech Stuff. It was fun to go back and look at this episode from the archives. I hope you guys enjoyed it. If you have any suggestions for future episodes of tech Stuff, whether it is a technology, a person who is instrumental in tech, maybe a company, Maybe there's someone you want me to interview, let me know. Send me a message. The email address

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