In Simple Terms: The Heisenberg Uncertainty Principle

Nature, Physics
[caption id="attachment_26306" align="alignright" width="480"] L to R: Niels Bohr, Werner Heisenberg, Wolfgang Pauli[/caption]Werner Heisenberg (1901-1976) was yet another bright German physicist. He was a "founder" of quantum mechanics, the physics of the subatomic. As with astrophysics, behavior at this level appears to vary from the physics of the everyday world. A Brief Description The velocity of an auto of mass m can be measured accurately. If its velocity remains constant, its location over time is predictable. This is the norm according to ordinary human experience. Yet, at submicroscopic levels, physicists experienced something different. For certain measurements, various pairs of variables could not both be accurately known simultaneously. Simultaneous measurement is only precise to a point. These pairs of variables are termed conjugate variables. The Standard Example The simplest example is…
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What Happens at Absolute Zero?

[caption id="attachment_7397" align="alignright" width="440"] Bose-Einstein condensate at billionths of a degree. Image by NIST[/caption] Classical physics suggests that at absolute zero, particles cease all motion. But what about quantum mechanics, the science of the very small? Ah, therein lies the rest of the story. From Gas to Frigid Solid It is well established fact that heated gas atoms or molecules move with great vigor. In fact, gas expands as energy increases, due to increased particle momentum. The reverse is also true. Cool a gas and it shrinks. Particle motion decreases. Particle momentum decreases. The atoms or molecules come closer together. At some point a liquid forms. Cool the liquid further and the result is a solid. Keep cooling the solid, and in theory it is possible to reach the coldest…
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