Astrophysicists Try to Resolve the Wave-Particle Duality

The smarter you get, the funkier your shirt must become lol. Loved this episode !

I must say, Dr. Charles Liu is one of my favorite guests on startalk. I love the way he is so calm and polite and can explain complex scientific concepts in very simple to understand ways that normal people can relate to.

If our brains evolved to understand the macroscopic world, can we ever truly grasp how something can be both a wave and a particle, or are we limited to describing it mathematically?

It’s so comforting to know Neil is also feeling troubled about the duality, and at the same time feeling nice that Charles is providing the perspective that thinking it makes sense

I'm an old guy (70+) and I struggled with grasping the p-w duality just like Dr. Tyson. But I finally understood that the problem is not with what the particle is, it's with our attempt to construct a model of it. It is what it is, but to understand and manipulate it in our minds we try to conform it to familiar phenomena from the macroscopic world—waves and particles being the most common ones—and when we do that, we are looking at it through a filter. It is simultaneously a wave and a particle because it is equally *neither* of those things, it's something that is so far beyond our macroscopic experience that we don't have any way to model it in our minds. The only way we can accurately understand and manipulate it is with math. But math is hard and ordinary folks can't communicate with it well, so we fall back on our models which don't work in all circumstances and we swap between them to communicate (imprecisely) about what we're observing. Think of an armadillo. If you've never seen one and don't know anything about it, I might describe it as like a turtle or like a mole, and you would call it a particle with turtle-mole duality.

Star talk is better than anything on TV

Contrary to Neil deGrasse Tyson’s claim that electrons gather in two places during the double-slit experiment, it has been demonstrated—most notably by Hitachi in the early 1980s—that an interference pattern still emerges even when electrons are sent through the slits one at a time.

I hope Neil deGrasse Tyson reads these comments. When Neil started to say at 7:25 about "but if I send electrons on purpose...", what he didn't say is how he managed to send the electrons "one at a time". If they were randomly sent at the slits, they would produce a wave pattern as each electron's wave function appears to interfere with itself. In order to send the electrons "on purpose" at each slit he has to first interact with the electron and therefore collapsed the wave function of that electron. If he sends them randomly at the slits, but has a detector at each slit to detect when an electron passes, he again has interfered with the electron and collapsed its wave function. As he states elesewhere in this video, the act of measurement changes the properties of the electron. The act of aiming the electrons, in the same way, changes the properties of the electron. As strange as it seems, even if you measure the electron after it has passed through a slit, it still collapses the wave function of that electron as though it had passed through one slit or the other. Also, counterintuitive to classical physics, the electron is a wave of pure probability. Its not a physical thing per se, but rather a number, a probabilistic value, at every point in space, all at once. In a sense, it comes into existence as a physical thing only when you interact with it, or when it collides with the back screen. The back screen itself is just another detector.

Dr Charles has this gift of sounding so patient that i feel like i can go back to his explanation without feeling a bit embarrassed for not understanding everything the first time i hear it lol

This conversation is a wonderful example of how important the quality of childhood teachers are and have become. The right teacher can help you understand ideas with their ability to artfully communicate.