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Q & A: can things touch?

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Most recent answer: 04/15/2017
Q:
hi there, came across various videos of 'how you can't touch anything based on the premise that atoms don't touch, and everything is made up of atoms --> molecules, etc.However, how is it that you can throw a ball, clap, walk, despite the concept that atoms don't touch ?here is the video being referenced:https://www.youtube.com/watch?v=yE8rkG9Dw4s
- jack (age 14)
vancouver, bc, canada
A:

Although the guy in the video has heard all the fancy physics words, he doesn't really get the ideas. He sounds like some show-off kids I remember from junior high school.

The alleged "electrostatic repulsion" doesn't keep two ordinary uncharged objects apart. The net electrical force is a weak vanderWaals attraction.  Repulsion does come from the Pauli exclusion principle, as the video says. But that repulsion is zero until the wave functions from the electrons on the two objects start to overlap. So in fact the objects do "touch" in the only physical sense possible, having overlapping wave functions.

The core of the error of the video is to switch back and forth between quantum physics and classical cartoon pictures in an inconsistent way.

Mike W.


(published on 04/15/2017)

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