2011年7月5日 · We present new theoretical estimates of the relative contributions of unresolved blazars and star-forming galaxies to the extragalactic gamma-ray background (EGB) and discuss constraints on the contributions from alternative mechanisms such as dark matter annihilation and truly diffuse gamma-ray production.

为了得到一个自洽的4D-EGB引力理论，人们已经提出了几种「正规化」的方式，比如：引入counter-term，Kaluza-Klein reduction和破缺时间微分同胚等正规化方式； 自由度：4D-EGB引力另一个有趣的性质是其具有和GR相同的自由度数目，即两个张量自由度。

2013年4月12日 · In the paper, we continually use the method of image stacking to study the origin of the extragalactic gamma-ray background (EGB) at GeV bands, and find that the Faint Images of the Radio Sky at Twenty centimeters (FIRST) sources undetected by the Large Area Telescope on the Fermi Gamma-ray Space Telescope can contribute about (56 {plus minus}6 ...

2024年9月10日 · A general covariant Einstein-Gauss-Bonnet Gravity in Four-Dimensional (4D EGB) spacetime is shown to bypass Lovelock's theorem and is free from Ostrogradsky instability. Meanwhile, the bumblebee theory is a vector-tensor theory.

2024年12月1日 · The 4D regularized EGB gravity theories allow for spherically symmetric black holes characterized by two horizons depending on their critical mass. In contrast, the bumblebee gravity model extends the Einstein-Maxwell theory that permits spontaneous symmetry breaking, resulting in the field acquiring a vacuum expectation value, thereby ...

2022年4月1日 · Fermi satellite released fairly accurate measurement of extragalactic gamma-ray background (EGB) from 100 MeV to 820 GeV, which dramatically improves our understanding of the high energy gamma-ray background.

2025年2月28日 · Again, by allowing a Gauss-Bonnet (GB) term in Lovelock’s action in higher dimensional spacetime, a new modified gravity called Einstein-Gauss-Bonnet (EGB) gravity has been introduced (Lanczos 1938). The GB term is a topological invariant term and does not contribute to the gravitational dynamics in typical 4D space-time.

In the present work, we are motivated to find non-exotic wormholes in 4D EGB gravity, i.e. wormhole solutions that satisfy NECs throughout the space–time. This paper is structured as follows: In § 2, we show a brief review of 4D EGB gravity. In § 3 we discuss the wormhole metric and solution of field equations in 4D EGB gravity.

2023年8月1日 · In this paper, we study thermodynamics of charged and uncharged 4-Dimension Einstein–Gauss–Bonnet (4D-EGB) black holes. The context of this study is the Visser’s holographic thermodynamics with a fixed anti-de Sitter radius and a variable Newton constant known as restricted phase space thermodynamics (RPST).

2023年2月28日 · In this paper, we study thermodynamics of charged and uncharged 4-Dimension Einstein-Gauss-Bonnet (4D-EGB) black holes. The context of this study is the Visser's holographic thermodynamics with a fixed anti-de Sitter radius and a variable Newton constant known as restricted phase space thermodynamics (RPST).