English
Related papers

Related papers: Testing inflation on all scales: a case study with…

200 papers

Cosmological $\alpha$-attractors stand out as particularly compelling models to describe inflation in the very early universe, naturally meeting tight observational bounds from cosmic microwave background (CMB) experiments. We investigate…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-22 Laura Iacconi , Hooshyar Assadullahi , Matteo Fasiello , David Wands

We investigate the two-stage inflation regime in the theory of hybrid cosmological $\alpha$-attractors. The spectrum of inflationary perturbations is compatible with the latest Planck/BICEP/Keck results, thanks to the attractor properties…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-11 Matteo Braglia , Andrei Linde , Renata Kallosh , Fabio Finelli

Cosmological perturbations, originating in the quantum fluctuations of the fields that drive inflation, are observed to be nearly scale invariant at the largest scales. At smaller scales, however, perturbations are not severely constrained…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-09 Ioannis Dalianis

[Abridged] The primordial scalar power spectrum is well constrained on large scales, primarily by the observations of the anisotropies in the cosmic microwave background (CMB). Over the last few years, it has been recognized that a sharp…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-21 H. V. Ragavendra , Pankaj Saha , L. Sriramkumar , Joseph Silk

Primordial black hole (PBH) abundance limits constrain the primordial power spectrum, and hence models of inflation, on scales far smaller than those probed by cosmological observations. Single field inflation models which are compatible…

High Energy Physics - Phenomenology · Physics 2014-11-20 Amandeep S. Josan , Anne M. Green

Primordial black holes (PBHs) provide an exciting prospect for accounting for dark matter. In this paper, we consider inflationary models that incorporate realistic features from high-energy physics -- including multiple interacting scalar…

High Energy Physics - Theory · Physics 2022-09-30 Sarah R. Geller , Wenzer Qin , Evan McDonough , David I. Kaiser

We study $\alpha$-attractor models with both E-model and T-model potential in an extended Non-Minimal Derivative (NMD) inflation where a canonical scalar field and its derivatives are non-minimally coupled to gravity. We calculate the…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-19 Raheleh Shojaee , Kourosh Nozari , Farhad Darabi

In light of the latest Planck and Atacama Cosmology Telescope (P-ACT) joint results on the primordial scalar power spectrum, we show that the $R^2$ inflation model extended with a non-minimally coupled scalar field $\chi$--namely the…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-18 Xinpeng Wang , Kazunori Kohri , Tsutomu T. Yanagida

We consider primordial black hole (PBH) production in inflationary $\alpha$-attractors. We discuss two classes of models, namely models with a minimal polynomial superpotential as well as modulated chaotic ones that admit PBHs. We find that…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-11 Ioannis Dalianis , Alex Kehagias , George Tringas

We propose and study the new (generalized) E-type $\alpha$-attractor models of inflation, in order to include formation of primordial black holes (PBHs). The inflaton potential has a near-inflection point where slow-roll conditions are…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-05 Daniel Frolovsky , Sergei V. Ketov , Sultan Saburov

We investigate the observational viability of a class of $\alpha$-attractors inflationary models in light of the most recent Cosmic Microwave Background (CMB) and Large-Scale Structure (LSS) data. By considering a double-well potential we…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-04 J. G. Rodrigues , S. Santos da Costa , J. S. Alcaniz

We discuss two-stage dilaton-axion inflation models [1] and describe $\alpha$-attractor models with either exponential or polynomial approach to the plateau. We implement one of the models of primordial black hole production proposed in [2]…

High Energy Physics - Theory · Physics 2022-08-31 Renata Kallosh , Andrei Linde

The discovery of gravitational waves from merging binary black holes has generated considerable interest in examining whether these black holes could have a primordial origin. If a significant number of black holes have to be produced in…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-07 H. V. Ragavendra , L. Sriramkumar

Recently multi-field inflation models that can produce large scalar fluctuations on small scales have drawn a lot of attention, primarily because they could lead to primordial black hole production and generation of large second-order…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-21 Laura Iacconi , David J. Mulryne

Here, generation of Primordial Black Holes (PBHs) from quartic potential in the presence of a tiny bump in non-canonical inflationary model has been inquired. It is demonstrated that, a viable inflationary era can be driven through the…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-05 Soma Heydari , Kayoomars Karami

All single-field inflationary models invoke varying degrees of tuning in order to account for cosmological observations. Mechanisms that generate primordial black holes (PBHs) from enhancement of primordial power at small scales posit…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-17 Philippa S. Cole , Andrew D. Gow , Christian T. Byrnes , Subodh P. Patil

We study a model of inflation with multiple pseudo-scalar fields coupled to a $U(1)$ gauge field through Chern-Simons interactions. Because of parity violating interactions, one polarization of the gauge field is amplified yielding to…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-12 Alireza Talebian , Seyed Ali Hosseini Mansoori , Hassan Firouzjahi

We study inflation in a recently proposed gravitational effective field theory describing the trace anomaly. The theory requires an additional scalar which is massless in the early universe. This scalar -- referenced as an anomalyon --…

High Energy Physics - Theory · Physics 2025-03-17 Gregory Gabadadze , David N. Spergel , Giorgi Tukhashvili

Primordial black holes (PBHs) generated by gravitational collapse of large primordial overdensities can be a fraction of the observed dark matter. In this paper, we introduce a mechanism to produce a large peak in the primordial power…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-11 Matteo Braglia , Dhiraj Kumar Hazra , Fabio Finelli , George F. Smoot , L. Sriramkumar , Alexei A. Starobinsky

We discuss new consistency relations for single field models of inflation capable of generating primordial black holes (PBH), and their observational implications for CMB $\mu$-space distortions. These inflationary models include a short…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 Ogan Özsoy , Gianmassimo Tasinato
‹ Prev 1 2 3 10 Next ›