-
Hitoshi Murayama (University of California Berkeley (US))12/07/2021, 14:00
I discuss how the origin of neutrino mass and baryon asymmetry may lead to gravitational wave signal from cosmic strings. In some cases of symmetry breaking patterns from GUT, cosmic strings may come with magnetic monopoles or domain walls, making the gravitational wave spectrum richer. We may learn how the GUT is broken if the gravitational wave signal can be mapped out for a wide range of...
Go to contribution page -
Kai Schmitz (CERN)12/07/2021, 14:40
Cosmic strings, which form during cosmological U(1)-symmetry-breaking phase transitions, represent an intriguing potential source of stochastic gravitational waves from the early Universe. While most studies thus far have focused on stable cosmic strings whose stability is guaranteed by the topology of the underlying vacuum structure, many Grand Unified Theories (GUTs) actually predict the...
Go to contribution page -
Lara Sousa (IA/CAUP)12/07/2021, 15:05
We discuss the stochastic gravitational wave background generated by cosmic superstring networks and show that heavier string types may leave distinct signatures on this spectrum. We show that these signatures may be within the reach of present and upcoming gravitational wave detector (particularly of pulsar timing arrays). This demonstrates that approximating the gravitational wave spectrum...
Go to contribution page -
Jose Juan Blanco-Pillado (IKERBASQUE & UPV/EHU)12/07/2021, 15:30
In this talk we will review the different ingredients that go into the
Go to contribution page
calculation of the stochastic gravitational wave background from cosmic strings and explain how one can extract the relevant information by performing large scale cosmological simulations of Nambu-Goto strings. Finally, we will also discuss
how current efforts to take into account gravitational backreaction can impact on... -
Daniele Steer12/07/2021, 16:10
In this talk we will first review the LIGO-Virgo O3 constraints on cosmic strings, both from the stochastic GW background (SGWB) and from a burst search. We will then go beyond the standard cosmic string scenario, and discuss (i) the effects of possible particle emission from cusps and kinks, both on the loop distribution as well as on different observables (the stochastic GW background as...
Go to contribution page -
Mr Alexander Jenkins (King's College London)12/07/2021, 16:50
The nonlinear memory effect is a fascinating prediction of general relativity (GR), in which oscillatory gravitational-wave (GW) signals are generically accompanied by a monotonically-increasing strain which persists in the detector long after the signal has passed. This effect is directly accessible to GW observatories, and presents a unique opportunity to test GR in the dynamical and...
Go to contribution page -
Sachiko Kuroyanagi12/07/2021, 17:15
Cosmic strings are one of the gravitational wave (GW) sources that can be probed by pulsar timing arrays (PTAs). In this work, we develop a detection algorithm for the GW burst from a cusp on a cosmic string and apply it to a Parkes PTA data release. We find four events with a false alarm probability of less than 1\%. However further investigation shows that all of these are likely to be...
Go to contribution page -
Prof. Yanou Cui (University of California, Riverside)12/07/2021, 17:40
In this talk I will discuss two important aspects of cosmology and particle physics that can be probed with GW signals from cosmic strings: probing the pre-BBN primordial dark age and axion physics. Gravitational waves (GWs) originating from the dynamics of a cosmic string network have the ability to probe many otherwise inaccessible properties of the early universe. In particular, I will...
Go to contribution page -
Dr Chiara Caprini (APC Paris)13/07/2021, 14:00
We present new results on the gravitational wave signal from kinetic turbulence in the aftermath of a first order phase transition in the early universe
Go to contribution page -
Jessica Turner (Durham University)13/07/2021, 14:40
In this talk, I discuss work where we calculate the velocity of the Higgs condensate bubble wall during a first-order electroweak phase transition in the early Universe. The interaction of particles with the bubble wall can be accompanied by the emission of multiple soft gauge bosons. When computed at fixed order in perturbation theory, this process exhibits large logarithmic enhancements...
Go to contribution page -
Carlos Tamarit (Technische Universität München)13/07/2021, 15:05
In first-order cosmological phase transitions, the asymptotic velocity of expanding bubbles is of crucial relevance for predicting observables like the spectrum of stochastic gravitational waves, or for establishing the viability of mechanisms explaining fundamental properties of the universe such as the observed baryon asymmetry. In these dynamic phase transitions, it is generally accepted...
Go to contribution page -
Dr Oliver Gould (University of Nottingham)13/07/2021, 15:30
A first-order phase transition in the early universe would have given rise to a stochastic gravitational wave background which may be observable today. In this talk, I will focus on the crucial problem of making reliable predictions in the face of infrared Bose enhancements at high temperature. Such enhancements break the alignment between the loop and coupling expansions, and typically lead...
Go to contribution page -
David Weir (University of Helsinki)13/07/2021, 16:10
In many extensions of the Standard Model, the electroweak transition is first order - in some cases, strongly so. The ensuing phase transition would result in collisions of bubbles of the new Higgs phase. These collisions, and the associated interactions of sound waves in the plasma, are substantial sources of gravitational waves. For a phase transition at or around the electroweak scale,...
Go to contribution page -
Marek Lewicki (University of Warsaw)13/07/2021, 16:50
We will discuss energy budget of first order phase transitions and identify models capable of supporting extreme supercooling necessary to feature bubble collisions as the main source of gravitational waves. We will also review new semi-analytical calculation of the spectrum appropriate in such strong transitions.
Go to contribution page -
Jorinde van de Vis (Deutsches Elektronen-Synchrotron DESY)13/07/2021, 17:15
Cosmological first-order phase transitions are predicted by many new physics models and could have facilitated the generation of the baryon asymmetry. Gravitational waves are a promising tool to study phase transitions in the early universe. In this talk, I focus on the energy budget of such phase transitions, which is an important factor in the prediction of the gravitational wave spectrum....
Go to contribution page -
Alberto Roper Pol13/07/2021, 17:40
The generation of primordial magnetic fields and its interaction with the primordial plasma during cosmological phase transitions is turbulent in nature. I will describe and discuss results of direct numerical simulations of magnetohydrodynamic (MHD) turbulence in the early universe and the resulting stochastic gravitational wave background (SGWB). In addition to the SGWB, the primordial...
Go to contribution page -
Jerome Martin (Institut d'Astrophysique de Paris)14/07/2021, 14:00
I will review the current status of inflation and discuss how
Go to contribution page
one can improve it using new observational probes. -
Rishi Khatri (Tata Institute of Fundamental Research)14/07/2021, 14:40
New interactions of neutrinos with a subdominant component of dark matter can prevent them from free streaming. As a result, the inflationary gravitational waves escape the damping by neutrinos and, with respect to the standard LCDM cosmology, there is enhancement of primordial gravitational wave amplitude and CMB B-modes on small scales. The effect on the CMB scalar acoustic oscillations is...
Go to contribution page -
Pedro Klaus Schwaller14/07/2021, 15:05
The dynamics of axions after inflation can give rise to an observable stochastic gravitational wave background. I will present new results for the GW spectrum from a lattice simulation of an axion-dark photon system in a radiation dominated universe, and furthermore show that this signal could explain the recently observed excess in the NANOGrav data.
Go to contribution page -
Anupam Mazumdar (Groningen University)14/07/2021, 15:30
Gravity and matter are universally coupled, and this unique universality provides us with an intriguing way to quantifying quantum aspects of space-time in terms of the number of gravitons. In particular, I will provide a limit on the number of gravitons if we trace out the matter degrees of freedom. I will obtain the universal bound on the number of gravitons. Since the number of gravitons...
Go to contribution page -
Emanuela Dimastrogiovanni (The University of New South Wales)14/07/2021, 16:10
Inflation is an epoch in the very early universe, characterised by a nearly exponential expansion. It provides an explanation for the origin of cosmic structure and it is in excellent agreement with current observations. The particle physics description of inflation is, however, still largely unknown. Primordial gravitational waves have the potential to shed new light on this epoch. In this...
Go to contribution page -
Zhong-Zhi Xianyu (Harvard University)14/07/2021, 16:50
Heavy particles can be produced on shell during inflation and leave distinct signals in the correlations of density fluctuations. These signals can be searched for in the future CMB/LSS/21cm observations. In this talk I will introduce the basics of this cosmological collider program. I will then describe some recent works along this direction with fun physics and visibly large signals,...
Go to contribution page -
Marc Kamionkowski (Johns Hopkins University)14/07/2021, 17:15
I will begin by reviewing the possibility that primordial black holes may make up the dark matter. I will then describe an array of analyses that can be done with CMB data and galaxy surveys to look for the effects of Hubble-scale gravitational waves and also to seek chirality in the gravitational-wave background.
Go to contribution page -
Gianluca Calcagni14/07/2021, 17:40
We will review recent results about the search for a cosmological imprint of quantum gravity in gravitational-wave physics.Tight constraints and a chance of detection for some models may come from modified dispersion relations, the luminosity distance of standard sirens and the stochastic gravitational-wave background.
Go to contribution page -
Misao Sasaki15/07/2021, 14:00
-
Ranjan Laha (Indian Institute of science (IN))15/07/2021, 14:40
My talk will be composed of two parts. During the first part, I will be talking about formation of transmuted black holes via particle dark matter accumulation in compact stars. Stellar objects catastrophically accrete non-annihilating dark matter, and the small dark core subsequently collapses, eating up the host star and transmuting it into a black hole. The wide range of allowed dark...
Go to contribution page -
Constantinos Skordis (CEICO, Institute of Physics, Czech Academy of Sciences)15/07/2021, 15:05
Many gravitational theories beyond general relativity have been proposed over the years as a physical explanation of the dark sector. All such theories affect the emission, propagation and detection of gravitational waves. In this talk, I will discuss some proposed scenarios and how the GW170817/GRB170817A simultaneous detection of gravitational and electromagnetic waves from the same source...
Go to contribution page -
Michael Fedderke (Johns Hopkins University)15/07/2021, 15:30
The science case for a broad program of gravitational wave (GW) detection across all frequency bands is exceptionally strong. At present, there is a dearth of coverage by existing and proposed searches in the GW frequency band lying between the peak sensitivities of PTAs and LISA, roughly 0.1-100 microhertz. In this talk, I will outline a conceptual mission proposal to access this band. I will...
Go to contribution page -
Dr Ville Vaskonen15/07/2021, 16:10
Since the dawn of gravitational wave (GW) astronomy, there has been increasing interest towards primordial black holes (PBHs). PBHs form binaries very efficiently at the time they decouple from the Hubble flow, and their present merger rate is high, assuming that they comprise a non-negligible fraction of dark matter. In this talk I will review the recent progress regarding the implications of...
Go to contribution page -
Cecilia Lunardini (Arizona State University)15/07/2021, 16:50
When a burst of neutrinos from a core collapse supernova passes by the Earth, it causes a permanent change in the local space-time metric, called the gravitational memory. Long considered unobservable, this effect will be detectable in the future, for a galactic supernova, at upcoming deci-Hertz gravitational wave interferometers. I present a new phenomenological description of the memory and...
Go to contribution page -
Dr Djuna Croon (TRIUMF)15/07/2021, 17:15
Gravitational waves from binary mergers encode not only the properties of individual non-luminous objects, but also of their astrophysical populations. With the growing dataset we can study for the first time how black hole properties are distributed. In this talk I will demonstrate how such studies can be used to learn about particle and nuclear physics in giant stars. The key insight is that...
Go to contribution page -
Tania Regimbau (Centre National de la Recherche Scientifique (FR))16/07/2021, 14:00
-
Naoki Seto16/07/2021, 14:40
The band 0.1-10Hz is just between the frequency regimes probed by the
Go to contribution page
ground-based detectors (LIGO, Virgo, KAGRA,..) and the proposed space
detectors (LISA, TianQin, Taiji). I briefly introduce the Japanese
plan DECIGO targeting this band and then discuss its targets,
including primordial stochastic background and compact
binaries. -
Francesco Muia16/07/2021, 15:05
The first direct detections of gravitational waves by the LIGO and VIRGO collaborations have opened up new avenues to explore the Universe. Currently operating and planned gravitational wave detectors mostly focus on the frequency range below 10 kHz, where signatures from known astrophysical sources are expected to be discovered. However, based on what happens with the electromagnetic...
Go to contribution page -
MICHAEL KRAMER (Max-Planck-Institut fuer Radioastronomie)16/07/2021, 15:30
Low-frequency gravitational waves cannot be detected with ground-based detectors.
Go to contribution page
While GW observations at frequencies in the micro- to mHz regime are planned with
spaced-based detectors, even lower frequencies, such as at nHz frequencies, can be
detected with pulsar timing arrays (PTAs). The talk summarises the PTA experiments,
describes the current status and prospects, and also... -
Antoine Petiteau (Universite Paris-Diderot - CNRS)16/07/2021, 16:10
-
Salvatore Vitale (Massachusetts Institute of Technology)16/07/2021, 16:50
Advanced LIGO and Virgo have detected dozens of gravitational waves, emitted from binary neutron stars and binary black holes. Third-generation observatories - such as Cosmic Explorer and the Einstein Telescope - will provide a significant boost in sensitivity and detect thousands of binary mergers per month, both from the local universe and from cosmological distances. In this talk I will...
Go to contribution page -
Raphael Flauger (The University of Texas at Austin)16/07/2021, 17:15
Observations of the temperature anisotropies of the cosmic microwave background radiation have been key to our understanding of the early universe. The cosmic microwave background also contains invaluable information about the early universe that can be revealed through precision observations of the polarization anisotropies. Perhaps most strikingly, measurements of the polarization...
Go to contribution page -
Oliver Buchmuller (Imperial College (GB))16/07/2021, 17:40
-
Barry Barish (Caltech)16/07/2021, 19:30
-
Lara Sousa (IA/CAUP)
-
Chiara Caprini (APC Paris)
-
Djuna Croon (TRIUMF)
Choose timezone
Your profile timezone: