Internal motion of atoms and collisions

AI Thread Summary
The discussion centers on the nature of atomic collisions, suggesting that if only internal atomic motion is considered, all collisions could be viewed as elastic. However, it acknowledges that in quantum mechanics, inelastic scattering, such as the Raman process, can occur. At a macro level, collisions may appear inelastic due to mass merging, but the atomic interactions could still be elastic if particles do not penetrate each other's boundaries. The conversation also touches on the concept of reversible mechanical laws leading to irreversible thermodynamics, highlighting that while collisions may be theoretically reversible, practical outcomes can lead to irreversible changes. Ultimately, the exploration reveals complexities in understanding atomic interactions and their implications for thermodynamics.
Dr.Brain
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I was thinking , if we take into account oly the internal motion of atoms , all collisions will turn out to be elastic. Wont they be?
 
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In quantum mechanics, photons can scatter off atoms inelastically in what is called a Raman process. Also, the technique known as deep inelastic scattering is a powerful tool for studying the structure of nuclei. So inelastic scattering can happen even at the quantum level.
 
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I am talking at macro-level . The collisions which look to be inelastic viewed form outside due to merging of masses ( in the case of inelastic collisions in which the the two rigid bodies don't mix up after collision but retain their boundary even though they may change their shapes ), but their particles were not allowed to enter each other's boundaries , which would imply they retorted back after collision . At micro-level thsi would mean everything happened elastically even though from outside it appears to be inelastic.

(This thread I posted because I looked at collision from a different point of view..I am in no mood to change any laws...)

BJ
 
It looks like you are trying to address the question how reversible mechanical laws produce irreversible thermodynamics...
 
Dr.Brain said:
I was thinking , if we take into account oly the internal motion of atoms , all collisions will turn out to be elastic. Wont they be?

Yes, but some of the collisions may make essentially irreverible changes
even though they are elastic. For example, if a collision is energetic enough
you could split an atom. While this is reversible in principle, it would be very
unlikely that you could put the atoms back the way they were. So in
practice there is effective irreverability even though each individual
transformation is reversible.
 
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