How Do Atoms Move at Absolute Zero?

Zero-point motion for an electron an atom seems just not really to involve motion, because an eigenstate does not have any dynamics or reflect higher excited states of the system.

 

In a compound with multiple particles (such as a crystal that has zero point motion of all the sound modes coexisting) there can be entanglement (like the correlations between the electrons in the Einstein-Podolsky-Rosen paradox) in the ground state.  This entanglement reflects zero-point motion of all the different excitations in the system moving through one another.

 

I will talk about how to define the "normal modes" for this dynamics, and explain how they are distributed in space and how to measure them. In a relativistic system, this dynamics is related to the virtual processes (such as particles and antiparticles appearing from the vacuum and then annihilating) and it is possible to reconstruct the dynamics of all the particles if one just knows how the ground state is formed by superimposing different configurations.