Zobrazeno 1 - 10
of 170
pro vyhledávání: '"Tsamis, N. C."'
The continual production of long wavelength gravitons during primordial inflation endows graviton loop corrections with secular growth factors. During a prolonged period of inflation these factors eventually overwhelm the small loop-counting paramete
Externí odkaz:
http://arxiv.org/abs/2409.12003
We re-consider the graviton self-energy induced by a loop of massless, minimally coupled scalars on de Sitter background. On flat space background it can be represented as a sum of two tensor differential operators acting on scalar structure function
Externí odkaz:
http://arxiv.org/abs/2407.07864
Publikováno v:
Class. Quant. Grav. 41 (2024) 215007
We develop a procedure for re-summing the large logarithms induced in gravity by loops of inflationary scalars. We first show how the scalar can be integrated out of the field equations in the presence of constant graviton field. We then extend this
Externí odkaz:
http://arxiv.org/abs/2405.01024
We present a new computation of the renormalized graviton self-energy induced by a loop of massless, minimally coupled scalars on de Sitter background. Our result takes account of the need to include a finite renormalization of the cosmological const
Externí odkaz:
http://arxiv.org/abs/2405.00116
We consider the massless, minimally coupled scalar on de Sitter background. Although the 1-loop divergences of the graviton 1PI 2-point function are canceled by the usual Weyl ($C^2$) and Eddington ($R^2$) counterterms, there is still a finite, nonze
Externí odkaz:
http://arxiv.org/abs/2312.15913
Publikováno v:
Universe 8 (2022) 376
We employ an unregulated computation the graviton self-energy from gravitons on de Sitter background to infer the renormalized result. This is used to quantum-correct the linearized Einstein equation. We solve this equation for the potentials which r
Externí odkaz:
http://arxiv.org/abs/2206.11467
Publikováno v:
JHEP 03 (2022) 069
We consider two nonlinear sigma models on de Sitter background which involve the same derivative interactions as quantum gravity but without the gauge issue. The first model contains only a single field, which can be reduced to a free theory by a loc
Externí odkaz:
http://arxiv.org/abs/2110.08715
Publikováno v:
Phil. Trans. R. Soc. A 380 (2021) 0187
We include the single graviton loop contribution to the linearized Einstein equation. Explicit results are obtained for one loop corrections to the propagation of gravitational radiation. Although suppressed by a minuscule loop-counting parameter, th
Externí odkaz:
http://arxiv.org/abs/2107.13905
Publikováno v:
Class. Quant. Grav. 38 (2021) 145024
Although matter contributions to the graviton self-energy $-i[\mbox{}^{\mu\nu} \Sigma^{\rho\sigma}](x;x')$ must be separately conserved on $x^{\mu}$ and ${x'}^{\mu}$, graviton contributions obey the weaker constraint of the Ward identity, which invol
Externí odkaz:
http://arxiv.org/abs/2103.08547
Publikováno v:
Phys. Rev. D 102, 025024 (2020)
We develop an analytic approximation for the coincidence limit of a massive scalar propagator in an arbitrary spatially flat, homogeneous and isotropic geometry. We employ this to compute the one loop corrections to the inflaton effective potential f
Externí odkaz:
http://arxiv.org/abs/1908.03814