Momentum-space entanglement in scalar field theory on fuzzy spheres
arXiv:2107.08907 · doi:10.1007/JHEP12(2021)101
Abstract
Quantum field theory defined on a noncommutative space is a useful toy model of quantum gravity and is known to have several intriguing properties, such as nonlocality and UV/IR mixing. They suggest novel types of correlation among the degrees of freedom of different energy scales. In this paper, we investigate such correlations by the use of entanglement entropy in the momentum space. We explicitly evaluate the entanglement entropy of scalar field theory on a fuzzy sphere and find that it exhibits different behaviors from that on the usual continuous sphere. We argue that these differences would originate in different characteristics; non-planar contributions and matrix regularization. It is also found that the mutual information between the low and the high momentum modes shows different scaling behaviors when the effect of a cutoff becomes important.
1+35 pages, 35 figures; Ver.2, minor changes; Ver. 3, added some explanation in Section 4, some paragraphs in Section 5, and some references. Version to appear in JHEP