1-5 July 2019
The University of Manchester
Europe/London timezone
- pascos2019@manchester.ac.uk
- +44 (0)161 275 4171
The Local Organising Committee
Parallel: Cosmological Probes
Place
Location: Schuster
Room: Rutherford Lecture Theatre
Date:
from 1 Jul 14:30 to 4 Jul 15:50
Conveners
-
1 Jul 14:30 - 16:10
- Dr. Bezrukov, Fedor (The University of Manchester)
-
1 Jul 16:40 - 18:20
Parallel 4
- Dr. Patil, Subodh (Niels Bohr Institute)
-
2 Jul 14:30 - 16:10
Parallel 4
- Mr. Teresi, Daniele (Università di Pisa)
-
2 Jul 16:40 - 18:20
Parallel 4
- Dr. Javier, Rubio (Helsinki Institute of Physics)
-
4 Jul 14:30 - 15:50
Parallel 4
- Prof. van de Bruck, Carsten (University of Sheffield)
Timetable | Contribution List
Displaying 25
contributions
out of
25
Bouncing cosmological solutions are found in a simple model of Einstein gravity coupled non-minimally to a self-interacting real scalar field. The characteristics of the solutions are presented and analyzed with an effective potential as a central tool. Bouncing solutions exist for the Higgs-like self interaction which is bounded from below, contrary to previous claims in favor of unbounded potent
... More
Presented by Prof. Yosef VERBIN
on
01/07/2019
at
15:50
We find a class of solutions for a homogeneous and isotropic universe in which the initially expanding universe stops expanding, experiences contraction, and then expands again (the "bounce"), in the framework of Einstein gravity with a real scalar field without violating the null energy condition nor encountering any singularities. Two essential ingredients for the bouncing universe are the posi
... More
Presented by Dr. Takahiro TERADA
on
01/07/2019
at
16:20
Deviations of the CMB spectrum from a black-body are a powerful probe of the three-point function of curvature perturbations. Dissipation of acoustic waves in the photon-electron-baryon fluid heats the plasma: the heating is not balanced by an appropriate change in photon number, and a Bose-Einstein spectrum is formed. A non-zero three-point function of curvature perturbations makes the heating ra
... More
Presented by Mr. Giovanni CABASS
on
01/07/2019
at
15:40
I will introduce our recent proposal that the state of the universe does *not* spontaneously violate CPT. Instead, the universe after the big bang is the CPT image of the universe before it, both classically and quantum mechanically. The pre- and post-bang epochs comprise a universe/anti-universe pair, emerging from nothing directly into a hot, radiation-dominated era. CPT symmetry selects the
... More
Presented by Latham BOYLE
on
01/07/2019
at
14:30
Several modern theories hypothesize that dark matter condenses to a superfluid phase around galaxies. If true, one key distinction from particle dark matter is dynamical friction, a process by which a massive perturber moving through a cloud of matter is slowed by the gravitational attraction to its own wake. I will describe the steady-state dynamical friction of a perturber moving through a sup
... More
Presented by Dr. Benjamin ELDER
on
02/07/2019
at
16:40
We revisit the effects of an early matter dominated era on gravitational waves induced by scalar perturbations. An early matter dominated era is a period during which the energy density of a massive field dominates the Universe before the reheating. We carefully take into account the evolution of the gravitational potential, source of the gravitational waves, around the transition from an early ma
... More
Presented by Mr. Keisuke INOMATA
on
02/07/2019
at
14:50
We discuss the question of frame equivalence of scalar-tensor theories in the path integral approach. We find that due to diffeomorphism invariance of the background geometry, the path integral measure must depend non-trivially on the metric. Under a change of frames, this induces new finite pieces in the Quantum Effective Action that must be taken into account to preserve frame equivalence at the
... More
Presented by Dr. Mario HERRERO-VALEA
on
02/07/2019
at
17:00
Several recent proposals to embed inflation into high-energy physics rely on inflationary dynamics characterized by a strongly non-geodesic motion. This in turn relaxes the conditions of slow-roll to allow for potentials that are steep in Planck units, a welcome feature in view of the eta problem and the recently much discussed swampland conjectures.
In this talk I will present a general fram
... More
Presented by Dr. Jacopo FUMAGALLI
on
01/07/2019
at
14:50
Could gravitational waves open the door to observe quantum gravity? In this talk I provide an initial answer, and show that results are quite promising. Recent developments in the effective field theory of quantum gravity uncovered the low-energy structure of the effective action in curved space. The long-distance portion of quantum loops manifests in a set of parameter-free non-local operators, w
... More
Presented by Dr. Basem ELMENOUFI
on
02/07/2019
at
15:50
In this talk I will discuss how different inflationary models are sensitive to inhomogeneities in the initial scalar field profile. In particular I will demonstrate that convex potentials always support large inhomogeneities and are more robust than concave ones. We developed a prescription to predict when a concave inflationary potential fails and I will show how it can be used to infer the initi
... More
Presented by Josu C. AURREKOETXEA
on
01/07/2019
at
15:30
Observations have offered strong support for the theory of inflation, but many details of the physics of the early Universe are still unknown. An observation of primordial isocurvature modes would change our view of the early Universe and point towards multi-field inflation. In this talk, I will describe some recent work towards the calculation of second-order effects from isocurvature modes,focus
... More
Presented by Pedro CARRILHO
on
01/07/2019
at
17:00
Based on numerical lattice simulations, I discuss the impact of the geometrical destabilization of inflation on the inflationary trajectory and show, that it can significantly change the inflationary predictions. Geometrical destabilization is a phenomenon in which the non-inflationary degrees of freedom are destabilized due to negative curvature of the fields space manifold affecting the evolutio
... More
Presented by Michal WIECZOREK
on
01/07/2019
at
16:00
The next generation detectors will verify, or at least constraint high energy phenomena, predicted by the vast variety of inflationary scenarios [1]. If a circularly polarized gravitational wave signal is detected, would point to the existence of parity breaking physics [2]. Here we consider, possible realizations of the effective field theory (EFT) of scalar-tensor gravity [3], which could offer
... More
Presented by Maria MYLOVA
on
02/07/2019
at
15:10
Primordial Black Holes (PBHs) are appealing candidates for dark matter in the universe but are severely constrained by theoretical and observational constraints. I will focus on the Hawking evaporation limits extended to Kerr Black Holes. These results have been obtained with a new code entitled BlackHawk that I will briefly present. In particular, I will review the isotropic extragalactic gamma r
... More
Presented by Dr. Alexandre ARBEY
on
04/07/2019
at
15:10
Primordial black holes have had a recent surge in popularity due to the LIGO/VIRGO detections and the possibility that they could make up all or part of the dark matter. However, even if you only want to produce one primordial black hole, there are tough requirements for the inflationary potential which can be translated into constraints on the primordial power spectrum. I will show that there is
... More
Presented by Philippa COLE
on
04/07/2019
at
14:50
We study the formation of primordial black holes (PBH) in a single field inflection point model of inflation wherein the effective potential is expanded up to the sextic order and the inversion symmetry is imposed such that only even power terms are retained in the potential. By working with a near inflection point in the potential, we find that PBHs can be produced in our scenario in a very relev
... More
Presented by Dr. Rajeev Kumar JAIN
I summarise constraints on new forces in the dark sector, originating from interactions with a dark energy scalar field. For standard constant couplings, cosmological observations constrain any new forces between dark matter particles to be very small, which is a challenge for quintessence model building in string theory. Instead, I propose to consider coupling functions with possess a minimum at
... More
Presented by Prof. Carsten VAN DE BRUCK
on
02/07/2019
at
16:20
Inflation and dark energy share many essential properties. I will show that these two eras can be easily unified into a common framework based on scale invariance. I will present the associated cosmological history and discuss how the inclusion of non-minimally coupled spectator fields may lead to the spontaneous symmetry breaking of internal symmetries and its eventual restoration at the onset of
... More
Presented by Dr. Rubio JAVIER
on
01/07/2019
at
16:40
I will introduce the innovative HI intensity mapping technique, which can turn the SKA and its MeerkAT precursor into precision cosmology machines. My talk will then focus on synergies between radio intensity mapping and optical galaxy surveys (e.g. GBT and SDSS, Euclid and SKA).
Presented by Dr. Alkistis POURTSIDOU
on
02/07/2019
at
15:40
Geometry has long been an important tool in physics, finding it's place in everything from Einstein's theory of General Relativity to the structure of Lie groups in Quantum Field Theory. In this talk I will extend the reach of geometry even further by presenting the Eisenhart lift. This formalism allows the classical dynamics of any scalar field theory to be re-expressed as a consequence of the ge
... More
Presented by Mr. Kieran FINN
on
01/07/2019
at
15:10
We consider a scalar field with a bottom-less linear potential, finding that cosmologies unavoidably end up with a crunch, even in scenarios compatible with the observed positive cosmological constant. Assuming that rebounces avoid singularities, this generates a new kind of multiverse: the universe undergoes cycles with different cosmological constants, all with finite lifetime regardless of the
... More
Presented by Mr. Daniele TERESI
on
02/07/2019
at
16:00
In the standard picture of cosmology, the Universe began at the Big Bang; the Big Bang itself is a singularity where the laws of physics break down. A quantum theory of gravity should resolve this singularity and help in understanding the initial state of the Universe needed to account for present observations. I will present some progress towards this goal in the group field theory approach to qu
... More
Presented by Dr. Steffen GIELEN
on
02/07/2019
at
14:30
TBA
Presented by Dr. Florian KUHNEL
on
04/07/2019
at
14:30
In the Standard Model, electroweak symmetry breaking is a crossover. In many extensions, the phase transition can be of first order – even strongly so. The resulting phase transition can then be a substantial source of gravitational waves. For a phase transition at or around the electroweak scale, these gravitational waves may be detectable by future or planned missions, such as LISA. This can i
... More
Presented by David WEIR
on
02/07/2019
at
15:30
Type: oral presentation
Session:
Parallel: Cosmological Probes
Track: Neutrinos and Non-Accelerator Probes of New Physics
We present a first overview of aSuperIso_DM, a platform based on Mathematica and C++ that is dedicated to the computation of various dark matter observables in the framework of a quantum field theory that can be cast under a Lagrangian form and that features a dark matter particle. aSuperIso_DM generalizes the supersymmetry-specific program SuperIso Relic by relying on an interface to FeynRules to
... More
Presented by Dr. Glenn ROBBINS
on
04/07/2019
at
15:30