From the 1 of 6 linked papers with an AI index.
6 papers
Is there ghost and tachyon free bounce in UV complete gravity theory?
Hao Hu, Alexey S. Koshelev, Abhishek Naskar
The paper investigates whether analytic infinite‑derivative gravity can produce a non‑singular bouncing universe without ghost or tachyon instabilities, finding that a negative cos…
Cancellation of UV divergences in ghost-free infinite derivative gravity
Alexey S. Koshelev, Oleg Melichev, Leslaw Rachwal
We consider the most general covariant gravity action up to terms that are quadratic in curvature. These can be endowed with generic form factors, which are functions of the d'Alem…
Convergent sum of EFT corrections to Schwarzschild metric requires UV locality
Yang Liu, Alexey S. Koshelev, Anna Tokareva +1
Corrections to vacuum black hole solutions of general relativity (GR) are considered in an effective field theory (EFT) framework, perturbatively in EFT coefficients, focusing on t…
Energy conditions for regular black holes in EFT of gravity
Ziyue Zhu, Alexey S. Koshelev, Yang Liu +1
As Einstein's gravity is a non-renormalizable theory, it can be a good description of physics only at the scales of energy or spacetime curvature below the Planck mass. Moreover, i…
Cosmic inflation in non-perturbative quantum gravity
Alexey S. Koshelev, Abhishek Naskar
String field theory motivated infinite-derivative models lead to non-local gravity modifications which form a promising class of quantum gravity candidates. In this paper we invest…
Quasi-normal modes in non-perturbative quantum gravity
Alexey S. Koshelev, Chenxuan Li, Anna Tokareva
Non-pertrubative quantum gravity formulated as a unitary four-dimensional theory suggests that certain amount of non-locality, such as infinite-derivative operators, can be present…