Negative T00 is indeed a characteristic of any plane wave whose phase velocity vector casts a negative projection on its time-averaged Poynting vector, but that quantity does not appear to be necessarily meaningful in the context of energy densities of electromagnetic signals which are necessarily of finite spatiotemporal extent. The astrophysical literature contains several negative-energy scenarios.
All Science Journal Classification (ASJC) codes
- Statistical and Nonlinear Physics
- Mathematical Physics
- Physics and Astronomy(all)