English

An inside view of the tensor product

Mathematical Physics 2023-03-28 v1 General Relativity and Quantum Cosmology High Energy Physics - Theory Category Theory math.MP Quantum Physics

Abstract

Given a vector-space  V ~V~ which is the tensor product of vector-spaces AA and BB, we reconstruct AA and BB from the family of simple tensors aba{\otimes}b within VV. In an application to quantum mechanics, one would be reconstructing the component subsystems of a composite system from its unentangled pure states. Our constructions can be viewed as instances of the category-theoretic concepts of functor and natural isomorphism, and we use this to bring out the intuition behind these concepts, and also to critique them. Also presented are some suggestions for further work, including a hoped-for application to entanglement entropy in quantum field theory.

Keywords

Cite

@article{arxiv.2303.14596,
  title  = {An inside view of the tensor product},
  author = {Rafael D. Sorkin},
  journal= {arXiv preprint arXiv:2303.14596},
  year   = {2023}
}

Comments

plainTeX, 29 pages. To appear in: Particles, Fields and Topology, Celebrating A.P. Balachandran, edited by T.R. Govindrajan, et al (World Scientific, Singapore). Most current version will be available at http://www.perimeterinstitute.ca/personal/rsorkin/some.papers/ (or wherever my home-page may be)

R2 v1 2026-06-28T09:33:50.821Z