-1
$\begingroup$

I have the impression that some literature say that Galilean invariance is broken by a uniform lattice. That is, although a uniform lattice like a tight binding model is translationally invariant, it is not Galilean invariant.

Could anyone expound this point?

As far as I can see, a discrete translation symmetry is quite similar to a continuum translation symmetry.

ps. Here we have a paper suggesting that a lattice system is not Galilean invariant.

enter image description here

$\endgroup$
2
  • 2
    $\begingroup$ Which literature? Which page? $\endgroup$
    – Qmechanic
    Commented Jun 11 at 14:02
  • $\begingroup$ By "Galilean invariance" do you mean continuous translational invariance and by "translational invariance" do you mean discrete translational invariance? Please define these two terms. $\endgroup$
    – QPhysl
    Commented Jun 11 at 14:18

1 Answer 1

1
$\begingroup$

A lattice isn't translationally invariant because if you translate by a vector that does not point from the origin to a lattice site then you do not end up with the same lattice. Therefore, it is not Galilean invariant.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.