My research is focused on modified theories of gravitation, and in particular the extensions of general relativity (GR) with a scalar field (scalar-tensor theories). I am interested in the properties of black holes, stars and cosmology in these theories. It is important to study the solutions for black holes and stars in modified gravity in order to predict new phenomena and/or constrain deviations from GR, especially given the growing precision of experimental tests that probe the nature of these objects.
Recently, my collaborators and I constructed a deformed version of the Kerr metric (which describes a rotating black hole in GR). The construction relies on the disformal map, and the spacetime presents many interesting features. While it is similar to Kerr in some aspects, certain properties (like noncircularity) are very different from those of black holes in GR, and they are worthy of further study. We also obtained experimental signatures of these solutions by examining the post-Newtonian orbit of stars around such objects.
- T. Anson, E. Babichev and C. Charmousis, "Deformed black hole in Sagittarius A", Phys. Rev. D 103 no. 12, (2021) 124035, arXiv:2103.05490.
- T. Anson, E. Babichev, C. Charmousis and M. Hassaine, "Disforming the Kerr metric", JHEP 01 (2021) 018, arXiv:2006.06461.
- T. Anson and E. Babichev, "Vainshtein screening for slowly rotating stars", Phys. Rev. D 102 no. 4, (2020) 044046, arXiv:2005.05990.
- T. Anson, E. Babichev, C. Charmousis, and S. Ramazanov, "Cosmological instability of scalar-Gauss-Bonnet theories exhibiting scalarization", JCAP 06 (2019) 023, arXiv:1903.02399.