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Name:  Wentao J.
Status:  student
Age:  20s
Location: N/A
Country: N/A
Date: 2000-2001


Question:
Dear sir, What is a k-space? Is it a real space or only a geometrical presentation of the discrete eingenvalues of the schrodinger equation or an inner property of a plane wave? Another question related to this is that, is the wave function capable of fully describing an electron's behavoir? Do you think it is possible that quantumn mechanics may be replaced by some fine theory which is totally different in the future?


Replies:
Wentao,

K-space is a model that makes working with quantum mechanics easier. Whether it is real depends on what you choose to call real. It corresponds to real properties, but it is not a space that something can move around in. It is not based on distances.

A wave function describes the STATE of an electron, not its behavior. A wave funtion can tell you what an electron is capable of doing, but it will not predict the electron's behavior. In terms of predicting things, the best a wave function can do is give an EXPECTATION VALUE. Measure the same quantity for millions of electrons in the same state. The expectation value corresponds to the average value among all the electrons, not the behavior of an individual electron.

We do not actually know whether any of physics is exactly correct. We know what seems to work, and under what conditions. Quantum mechanics may or may not be correct. Nobody has as of yet come up with anything that works better than quantum mechanics when working with individual particles.

Dr. Ken Mellendorf



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