Cubic lattice, masses and springs, fire little mass at it.

AI Thread Summary
A cubic lattice of masses connected by springs can theoretically be subjected to a single mass fired at it, resulting in translational motion with minimal vibrational energy. The discussion explores whether it's possible to achieve this outcome without imparting significant vibrations to the lattice. A comparison is made to a one-dimensional lattice, where a gentle shove produces mostly translational movement, while a hard shove leads to both translational and vibrational energy. The inquiry draws parallels to the Mössbauer effect, seeking a classical system that allows for gamma emission without producing crystal phonons. Understanding these dynamics could provide insights into energy transfer in lattice systems.
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Suppose I have a cubic lattice of N^3 masses, M, each connected to six nearest neighbors with springs of constant k free to move but at rest. Now fire a single mass, m, with velocity v at surface of the lattice such that no rotation can be imparted to the cubic lattice. Let the fired mass bounce off a single lattice mass so that both masses move in the opposite direction.

Can we fire a mass at a lattice at rest and only produce translation of lattice with no or little vibration of the lattice?

I wanted to understand if there was a classical system similar to the crystal in the Mössbauer effect where we can have gamma emission with no crystal phonons produced.

Thanks for any help!
 
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I think what I'm asking can be simplified with the following classical setup. Let there be a one dimensional lattice of N masses M, connected by springs with the whole system constrained to move on a line. Suppose we give the first mass of this system a slow gentle shove. I think the math would show that the lattice would move as a whole with very little vibrational energy being produced. But now suppose we give the first mass of the lattice a hard fast shove then it seems the math would also show that now the lattice would gain both translational and vibrational energy?
 
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