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If exact location of an electron is known, can we predict future?

1 points by Haddit ↗ HN
If the exact location of an electron is somehow known(with advent of technology ) , We can also predicts its location after nth time. That implies we can know the state of all electrons which constitute the matter. So can we predict future through that ? Is there any relevant work on it

7 comments

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bcbrown
No. Read up on the Heisenberg Uncertainty Principle. Knowing the exact location actually means we have precisely zero knowledge of its future location, because position and momentum are complementary variables.
MichaelCrawford
The only way to find the location of any particle - including an electron - is to scatter another particle off of it. But by doing so, we disturb the electron. We'll know where it was when it scattered, but not where it goes.
Haddit
So if we find the location, (if). future becomes predictable?
MichaelCrawford
No.

It's hard to explain without drawing diagrams. However it is possible to understand it in a purely conceptual way, without math.

Consider that if you pass some photons through a pair of parallel slits onto photographic film or a digital camera sensor, a pattern of light and dark fringes will result.

That has to do with not being able to tell which slit any one photon went through.

If you have some moderate understanding of Calculus, read all three volumes of The Feynman Lectures on Physics, by Feynman, Leighton and Sands. The third volume covers quantum mechanics, but it is helpful to read the first two as well.

MichaelCrawford
Quantum tunneling is a good, specific example. It is not predicted by classical mechanics.

If I have a particle which is bound inside a potential well, say an electron which is part of an atom, by virtue of being electrically attracted to the atom's nucleus, from time to time it can escape the potential well.

Say for example I have a hydrogen atom, with an electron and a proton, and a positively-ionized hydrogen atom - that's actually just a bare proton.

From time to time the electron will bind to the other proton, without appearing to cross the space in-between.

[dead] vonsydov
I know I can predict the path of a ball when I throw it in the air. And I can repeatedly test this to prove I can predict it.
arisAlexis
this is a famous topic for having arguments. you either believe in determinism so that if you know all the variables and the laws (I am not talking about specific variables such as location etc but ALL of them and ALL the rules that govern them) then you can predict ALL of the future. Quantum mechanics add a random variable so that makes it impossible. Einstein was deeply troubled by this and his initial reaction to quantum mechanics was " I don't believe god plays dice) " but then changed his mind.