# Exact spacetimes in higher order gravity theories

**Advisor:** Robert Švarc (ITP MFF CUNI)

**Funding:** base scholarship supplemented from a national grant for the first year. Extension of the supplement beyond the first year depends on availability of funds.

**Website:** http://utf.mff.cuni.cz/~svarc/

**Contact:** robert.svarc@mff.cuni.cz

Although the Einstein general relativity is the most successful description of gravity so far, passing many sophisticated experimental tests, there are various reasons to analyse its extensions. The most natural way how to introduce the additional corrections into the field equations is via modification of the classic Einstein-Hilbert action allowing the higher order curvature terms. This typically leads to a significantly more complicated system of the equations for a spacetime metric.

In our project we will focus on finding exact solutions in the case of particular extended theories (generic quadratic gravity, Gauss-Bonnet theory, Einstein-Weyl theory), their mathematical analysis, and physical interpretation, see e.g. [1-4]. Our main aim will be to study geometries admitting black holes or exact models of gravitational waves. These goals should be supplemented by generalisations of mathematical concepts advantageously employed in standard general relativity [5].

References:

[1] Podolský, Švarc, Pravda, Pravdová, Phys.
Rev. D 98, 021502(R) (2018)

[2] Švarc, Podolský, Pravda, Pravdová, Phys.
Rev. Lett. 121, 231104 (2018)

[3] Podolský, Švarc, Pravda, Pravdová, Phys.
Rev. D 101, 024027 (2020)

[4] Švarc, Podolský, Hruška, Phys. Rev. D 102,
084012 (2020)

[5] Pravda, Pravdová, Podolský, Švarc, Phys. Rev. D 95,
084025 (2017)