nLab reflection positivity

Idea

In quantum field theory reflection positivity is the incarnation of unitarity under Wick rotation.

References

• Arthur Jaffe, Reflection Positivity Then and Now (arXiv:1802.07880)

Discussion with tools from extended TQFT and stable homotopy theory (aimed at invertible TQFTs):

• Daniel Freed, Michael Hopkins, Reflection positivity and invertible topological phases, Geometry & Topology 25 (2021) 1165–1330 [arXiv:1604.06527, doi:10.2140/gt.2021.25.1165]

In relation to the conformal bootstrap:

• Leandro Lanosa, Mauricio Leston, Mario Passaglia, Interplay between reflection positivity and crossing symmetry in the bootstrap approach to CFT (arXiv:2112.00232)

See also:

• Gohin Shaikh Samad, W.N.Polyzou: Reflection positivity in Euclidean formulations of relativistic quantum mechanics of particles [arXiv:2506.20526]