English

Newton's identities and positivity of trace class integral operators

Quantum Physics 2023-03-23 v4 Mathematical Physics math.MP

Abstract

We provide a countable set of conditions based on elementary symmetric polynomials that are necessary and sufficient for a trace class integral operator to be positive semidefinite, which is an important cornerstone for quantum theory in phase-space representation. We also present a new, efficiently computable algorithm based on Newton's identities. Our test of positivity is much more sensitive than the ones given by the linear entropy and Robertson-Schr\"odinger's uncertainty relations; our first condition is equivalent to the non-negativity of the linear entropy.

Keywords

Cite

@article{arxiv.2207.06119,
  title  = {Newton's identities and positivity of trace class integral operators},
  author = {G. Homa and R. Balka and J. Z. Bernád and M. Károly and A. Csordás},
  journal= {arXiv preprint arXiv:2207.06119},
  year   = {2023}
}

Comments

Improved introduction and small corrections, coloured figures added. 15 pages, 6 figures