English
Related papers

Related papers: Bootstrapping the Cosmological Collider with Reson…

200 papers

We study how inflationary observables associated with primordial tensor modes are affected by coupling the minimal field content with an extra spin-2 particle during inflation. We work with a model that is ghost-free at the fully non-linear…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-22 Emanuela Dimastrogiovanni , Matteo Fasiello , Gianmassimo Tasinato

We explore whether multifield inflationary models make unambiguous predictions for fundamental cosmological observables. Focusing on $N$-quadratic inflation, we numerically evaluate the full perturbation equations for models with 2, 3, and…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-29 Richard Easther , Jonathan Frazer , Hiranya V. Peiris , Layne C. Price

Nonminimal coupling between the inflaton and the Ricci scalar plays a crucial role in shaping the predictions of single-field inflationary models. While a quartic potential with such coupling represents one of the simplest realizations…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-24 Waqas Ahmed , Mansoor Ur Rehman

We analyse the efficiency of future large scale structure surveys to unveil the presence of scale dependent features in the primordial spectrum --resulting from cosmic inflation-- imprinted in the distribution of galaxies. Features may…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-04 Gonzalo A. Palma , Domenico Sapone , Spyros Sypsas

We introduce a frame-covariant formalism for inflation of scalar-curvature theories by adopting a differential geometric approach which treats the scalar fields as coordinates living on a field-space manifold. This ensures that our…

High Energy Physics - Phenomenology · Physics 2018-01-09 Sotirios Karamitsos , Apostolos Pilaftsis

Oscillating massive fields in the primordial universe can be used as Standard Clocks. The ticks of these oscillations induce features in the density perturbations, which directly record the time evolution of the scale factor of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Xingang Chen , Mohammad Hossein Namjoo , Yi Wang

If cosmic inflation suffered tiny time-dependent deviations from the slow-roll regime, these would induce the existence of small scale-dependent features imprinted in the primordial spectra, with their shapes and sizes revealing information…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 Sander Mooij , Gonzalo A. Palma , Grigoris Panotopoulos , Alex Soto

We study primordial perturbations from hyperinflation, proposed recently and based on a hyperbolic field-space. In the previous work, it was shown that the field-space angular momentum supported by the negative curvature modifies the…

High Energy Physics - Theory · Physics 2017-12-08 Shuntaro Mizuno , Shinji Mukohyama

Ghost inflation is a well-known framework in which cosmological fluctuations can generate enhanced primordial non-Gaussianity, typically of the equilateral type. In its original form, however, it is in tension with current observational…

High Energy Physics - Theory · Physics 2026-01-22 Matheus Curado Ferreira , F. T. Falciano , Guilherme L. Pimentel

We explore how inflationary features shape the early stages of cosmic structure formation. Using the transfer function formalism, we trace the evolution of primordial perturbations, showing how causal physics and oscillatory signatures from…

General Relativity and Quantum Cosmology · Physics 2026-02-17 K. El Bourakadi , M. Yu. Khlopov , M. Krasnov , H. Chakir , M. Bennai

We study a cosmological scenario in which inflation is preceded by a bounce. In this scenario, the primordial singularity, one of the major shortcomings of inflation, is replaced by a non-singular bounce, prior to which the universe…

General Relativity and Quantum Cosmology · Physics 2015-05-27 Marc Lilley , Larissa Lorenz , Sebastien Clesse

If during inflation the inflaton couples to a "fossil" field, some new scalar, vector, or tensor field, it typically induces a scalar-scalar-fossil bispectrum. Even if the fossil field leaves no direct physical trace after inflation, it…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-14 Liang Dai , Donghui Jeong , Marc Kamionkowski

The decay of massive particles during inflation generates characteristic signals in the squeezed limit of the primordial bispectrum. These signals are in particular distinctive in the regime of the quasi-single field inflation, where…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-08 Yi Wang , Yi-Peng Wu , Jun'ichi Yokoyama , Siyi Zhou

The apparent alignment of the cosmic microwave background multipoles on large scales challenges the standard cosmological model. Scalar field inflation is isotropic and cannot account for the observed alignment. We explore the imprints, a…

Astrophysics · Physics 2010-04-14 Christian G. Boehmer , David F. Mota

We initiate a systematic study of precision calculation of the inflation correlators at the 1-loop level, starting in this paper with bosonic 1-loop bispectrum with chemical-potential enhancement. Such 1-loop processes could lead to…

High Energy Physics - Phenomenology · Physics 2022-03-02 Lian-Tao Wang , Zhong-Zhi Xianyu , Yi-Ming Zhong

In this paper we study the generation of primordial perturbations in a cosmological setting of bigravity during inflation. We consider a model of bigravity which can reproduce the $\Lambda$CDM background and large scale structure and a…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-02 Giulia Cusin , Ruth Durrer , Pietro Guarato , Mariele Motta

In inflationary cosmological models driven by an inflaton field the origin of the primordial inhomogeneities which are responsible for large scale structure formation are the quantum fluctuations of the inflaton field. These are usually…

General Relativity and Quantum Cosmology · Physics 2009-02-20 Albert Roura , Enric Verdaguer

Primordial oscillatory features in the power spectrum of curvature perturbations are sensitive probes of the dynamics of the early Universe and can provide insights beyond the standard inflationary scenario. While these features have been…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-09 Mario Ballardini , Nicola Barbieri

We analyze the signatures of inflationary models that are coupled to strongly interacting field theories, a basic class of multifield models also motivated by their role in providing dynamically small scales. Near the squeezed limit of the…

High Energy Physics - Theory · Physics 2015-06-12 Daniel Green , Matthew Lewandowski , Leonardo Senatore , Eva Silverstein , Matias Zaldarriaga

The generation of large-scale magnetic fields in inflationary cosmology is explored, in particular, in a kind of moduli inflation motivated by racetrack inflation in the context of the Type IIB string theory. In this model, the conformal…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Kazuharu Bamba
‹ Prev 1 3 4 5 6 7 10 Next ›