Allahverdi, Rouzbeh Amin, Mustafa A. Berlin, Asher Bernal, Nicolás Byrnes, Christian T. Sten Delos, M. Erickcek, Adrienne L. Escudero, Miguel Figueroa, Daniel G. Freese, Katherine
...

It is commonly assumed that the energy density of the Universe was dominated by radiation between reheating after inflation and the onset of matter domination 54,000 years later. While the abundance of light elements indicates that the Universe was radiation dominated during Big Bang Nucleosynthesis (BBN), there is scant evidence that the Universe ...

Ghiglieri, J. Jackson, G. Laine, M. Zhu, Y.
Published in
Journal of High Energy Physics

We compute the production rate of the energy density carried by gravitational waves emitted by a Standard Model plasma in thermal equilibrium, consistently to leading order in coupling constants for momenta k ∼ πT. Summing up the contributions from the full history of the universe, the highest temperature of the radiation epoch can be constrained b...

Sirunyan, A. M. Tumasyan, A. Adam, W. Ambrogi, F. Bergauer, T. Brandstetter, J. Dragicevic, M. Erö, J. Escalante Del Valle, A. Flechl, M.
...
Published in
The European Physical Journal C

Anisotropies in the initial energy density distribution of the quark-gluon plasma created in high energy heavy ion collisions lead to anisotropies in the azimuthal distributions of the final-state particles known as collective anisotropic flow. Fourier harmonic decomposition is used to quantify these anisotropies. The higher-order harmonics can be ...

Zumalacarregui, Miguel

Discrepant measurements of the Universe's expansion rate ($H_0$) may signal physics beyond the standard cosmological model. Here I describe two early modified gravity mechanisms that reconcile the value of $H_0$ by increasing the expansion rate in the era of matter-radiation equality. These mechanisms, based on viable Horndeski theories, require si...

Yousaf, Z. Khlopov, Maxim Yu. Bhatti, M.Z. Naseer, T.

The aim of this paper is to generalize the definition of complexity for the static self-gravitating structure in $f(R,T,Q)$ gravitational theory, where $R$ is the Ricci scalar, $T$ is the trace part of energy momentum tensor and $Q\equiv R_{\alpha\beta}T^{\alpha\beta}$. In this context, we have considered locally anisotropic spherical matter distri...

Grain, Julien Vennin, Vincent

Contracting cosmologies are known to be flawed with a shear instability, where the contribution from the anisotropic stress to the overall energy density grows as $a^{-6}$, with $a$ the scale factor. Classically, whether or not this contribution becomes important before the bounce depends on its initial value, which can always be sufficiently fine ...

Martin, Jérôme Papanikolaou, Theodoros Pinol, Lucas Vennin, Vincent

At the end of inflation, the inflaton oscillates at the bottom of its potential and these oscillations trigger a parametric instability for scalar fluctuations with wavelength $\lambda$ comprised in the instability band $(3H m)^{-1/2}

Bertacca, Daniele Ricciardone, Angelo Bellomo, Nicola Jenkins, Alexander C. Matarrese, Sabino Raccanelli, Alvise Regimbau, Tania Sakellariadou, Mairi

The detection and characterization of the Stochastic Gravitational Wave Background (SGWB) is one of the main goals of Gravitational Wave (GW) experiments. The observed SGWB will be the combination of GWs from cosmological (as predicted by many models describing the physics of the early Universe) and astrophysical origins, which will arise from the ...

Hanımeli, Ekim Taylan Lamine, Brahim Blanchard, Alain Tutusaus, Isaac

In this work, we investigate cosmologies where the gravitational constant varies in time, with the aim of explaining the accelerated expansion without a cosmological constant. We achieve this by considering a phenomenological extension to general relativity, modifying Einstein's field equations such that $G$ is a function of time, $G(t)$, and we pr...

Song, Taesoo Moreau, Pierre Aichelin, Joerg Bratkovskaya, Elena

In this article we investigate how the drag coefficient $A$ and $\hat{q}$, the transverse momentum transfer by unit length, of charm quarks are modified if the QGP is not in complete thermal equilibrium using the dynamical quasi-particle model (DQPM) which reproduces both, the equation-of-state of the QGP and the spatial diffusion coefficient of he...