Slow roll approximation

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August undefined, 2024

Webb1 okt. 2024 · Slow roll inflation requires that the effective inflaton mass should be much smaller than the Hubble parameter during inflation, that is m2 ≪ H2. However, when we try to build an inflation model in the framework of string theory or supergravity, one often encounter an Hubble induced inflaton mass, that is m2 ∼ H2[1], [2]. WebbThe ‘slow-roll approximation’ [3, 4, 5], which neglects the most slowly changing terms in the equations of motion, is the most widely used. Although this approximation works well in …

Formalizing the slow-roll approximation in inflation

WebbSlow roll approximation in quantum cosmology Oliver Janssen Center for Cosmology and Particle Physics, New York University, New York, NY 10003, USA Abstract Webb16 dec. 2024 · When the slow-roll approximation is violated in constant-roll inflation, the scalar and tensor perturbations equations derived in the slow-roll approximation case also require modification. ips berisso

Phys. Rev. D 62, 103520 (2000) - Precision of slow-roll predictions …

Webbapproximation(SRA); this assumes that a term can be neglected in each of the equations of motion to leave the simpler set (41) (42) If we define slow-roll parameters[3] (43) where … Webb23 jan. 2024 · The slow-roll approximation is an analytical approach to study dynamical properties of the inflationary universe. In this article, systematic construction of the slow … Webb4 aug. 1994 · The meaning of the inflationary slow-roll approximation is formalised. Comparisons are made between an approach based on the Hamilton-Jacobi equations, … ips beyond smi

arXiv:2009.06282v1 [gr-qc] 14 Sep 2024 - ResearchGate

Shear viscous effects on the primordial power spectrum from …

Webb3 apr. 2014 · the slow-roll approximation and in ligh t of the data from BICEP2. Along the wa y, w e ﬁnd general consistency relations at which observ ables are sub ject if the … Webbthe slow roll parameter η. τ on the other hand is also used to denote the optical depth to the surface of last scattering... A photon travels a coordinate distance τ during conformal … orc workwear websiteWebb29 juni 2024 · For the slow-roll approximation the scalar field behaves as an effective dark energy. The form of the potential is clearly unknown and many different potentials have been studied and confronted with observations. These two regimes of accelerated expansion are treated independently. ips beneficio

"Webb5 apr. 2024 · We re-express all slow-roll parameters, slow-roll conditions and the acceleration condition in NLS form. The WKB approximation in the NLS formulation is also discussed while simplifying to the linear case. Most of the Schr¨odinger potentials in the NLS formulation are very slowly varying; hence the WKB approximation is valid in some … " - Slow roll approximation

Slow roll approximation

Webb16 juli 2024 · By taking the slow-roll approximation, we generated interesting scenarios where a Klein Gordon potential leads to observationally consistent inflation observables. Our results make it clear-cut that in addition to the Ricci scalar and scalar fields, the trace of energy momentum tensor also plays a major role in driving inflationary scenarios. Webb26 okt. 2000 · Inflationary predictions for the anisotropy of the cosmic microwave background radiation are often based on the slow-roll approximation. We study the …

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Webb11 mars 2024 · This is the slow-roll approximation and has been recognized as a practical way to realize inflation. In this scenario, instead of tunneling out of a false vacuum state, … WebbIn inflationary theory, many papers start off by making the slow-roll approximation, on which many things depend. This approximation is usually presented by requiring that two 'slow-roll parameters' are small: ϵ V ≡ 1 16 π G ( V ′ V) 2 ≪ 1. η V ≡ 1 8 π G ( V ″ V) ≪ 1.

Webbslow-roll approximation in classical cosmology to quantum cosmology, where the instantons are complex functions. Our new ﬁnding is that the equations of motion for … Webb3 apr. 2014 · Testing the slow-roll approximation, Hybrid Natural Inflation and the tensor index with BICEP2 Authors: Mariana Carrillo Gonzalez Imperial College London Gabriel Germán Universidad Nacional...

Webb14 aug. 2024 · In this framework and assuming the slow-roll approximation, a possible methodology for the reconstruction of inflation is the parametrization of these cosmological quantities or parameters in terms of the number of e- folds N.

Webb14 sep. 2024 · Our derivation demonstrates a result anticipated by Hartle, Hawking and Hertog in Phys. Rev. D 77 (2008) 123537 [arXiv:0803.1663], sharpens Vilenkin's result in …

Webbbe neglected in the equation of motion, which then takes the slow-rolling form for homogeneous ﬁelds: 3Hφ˙ = −dV/dφ. (147) In combination with Friedmann’s equation in … orc world championship 2021Webbwithout slow-roll approximation Jinn-Ouk Gong∗ Department of Physics, KAIST, Daejeon, Republic of Korea International Center for Astrophysics, KASI, Daejeon, Republic of Korea† October 16, 2024 Abstract We study an inﬂationary scenario where thermal inﬂation is followed by fast-roll inﬂation. ips bethelWebbSlow-roll inflation and the primordial metric perturbation spectrum . MSc Thesis September 2009 . Author: Trevor Peter Hardcastle . Imperial College London . Abstract . Inflation is … ips beetle preventionWebb23 jan. 2024 · The slow-roll approximation is an analytical approach to study dynamical properties of the inflationary universe. In this article, systematic construction of the slow-roll expansion for effective loop quantum cosmology is presented. ips benqWebbslow-roll approximation, which is expected to be accurate to a few percent or better. From these expressions, we can compute the spectral indices [8]: ns ≃ 1− 6ǫ+ 2η ; nt ≃ −2ǫ. (24.6) Another useful quantity is the ratio of the two spectra, deﬁned by r ... ips besanconWebbapproximate solutions with these types of dynamics for various types of gravity theories. For the case of f(R)-gravity on the basis of the exact solutions and ones obtained in slow-roll approximation it is shown that widely discussed Starobinsky [1,39,40,64–66] and non-minimal Higgs [67–69] inﬂationary orc worldbuildingWebbWe compute the primordial curvature spectrum generated during warm inflation, including shear viscous effects. The primordial spectrum is dominated by the thermal fluctuations of the radiation bath, sourced by the diss… orc world map