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So how is it possible that electrons act differently when we observe them?

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The matter such as the double slit experiment of Heisenberg's uncertainty principle shows us that matter is far removed from the known physical reality.

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Can you elaborate on this?

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I think one of the things that makes it hard to think about electrons and atoms is that at such tiny scales we're always thinking by analogy of something that's like something else that we have in our normal experience.

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And we normally think of little billiard balls, little balls flying through space.

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That's often times the way we think of electrons and so on.

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But actually in the last hundred years the way that we think about microscopic quantum mechanics probably gives another analogy a lot better footing.

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Which is to think of it as really something more like a wave in the air.

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So right now I'm talking to you through the air and there are sound waves coming at you.

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And if you know anything about music you know in music there are resonances.

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So if I'm playing on an instrument I get different notes at different points of frequency and those are different what do we call resonances.

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And so when we think about the electron around an atom and so on.

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In a lot of ways what we know now from modern field theory is that we should sort of think of it fundamentally as more like a wave filling space.

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And then the particles the electrons are things that sometimes are coming out from that wave picture as resonances but not always.

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So in some ways a lot of our intuition about these things comes from thinking of little billiard balls flying around and asking where is that billiard ball at all different points and so on.

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And actually that's often times not the right question to ask.

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One of the things I think is kind of an important aspect of modern physics that doesn't really get talked about a lot is there are two types of particles.

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Two broad classes.

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One of them is what we call fermions and the other is bosons.

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And fermions are electrons, protons, all the sort of things that you think of as going into atoms.

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And they have a special property that they cannot be doing the same thing at the same time.

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So you cannot have two electrons doing exactly the same thing.

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So one thing that that leads to is that they push away from each other.

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And so all of the sort of solid things that we feel around us are that property comes from the fact that they're fermions pushing away from each other.

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On the other hand things like light and sound are energy waves.

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And those particles can pass through each other and they often times they don't repel in the same way.

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And so we normally think of photons and light as easily as a wave where the waves pass through each other.

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And the electrons we think of as very solid.

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But quantum mechanics tells us well sometimes it's not so cleanly different from each other.

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Sometimes the electrons have wave properties and sometimes the photons have particle, the light has particle properties.

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So I think in some ways when we can get into trouble when we try to think of the atomic things as sort of too much like a billiard ball.

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Too much as a little object flying around when in fact the wave picture is a much better picture a lot of times.

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Thank you.

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Thank you.

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Thank you.