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Elena Pierpaoli22/08/2022, 09:10Plenary/Parallel talk
Since its discovery, the study of the cosmic microwave background anisotropies has been pursued from space, balloons and the ground with great success. The results have helped in shaping the current standard cosmological model, and forged the new questions we are now trying to answer. I will review the main legacy of past experiments, and discuss the scientific goals and expectations for the...
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Rogério Rosenfeld22/08/2022, 09:50
The Vera C. Rubin Observatory under construction in Chile will conduct the 10-year Legacy Survey of Space and Time (LSST) that will produce an unprecedented astronomical data set. This data set will be used to explore several different aspects of the universe, such as: the nature of dark energy and dark matter, objects in the solar system, mapping the Milky Way and transient phenomena in the...
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Chiara Moretti22/08/2022, 11:00Plenary/Parallel talk
ESA's Euclid satellite, designed to map the geometry of the Universe and scheduled for launch in 2023, will observe billions of galaxies with the ultimate goal of unveiling the nature of dark matter and dark energy. I will give an overview of the instrument and the current status of the Euclid mission. I will then focus on one of its main probes, galaxy clustering, and describe the...
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Francesc Ferrer Escursell22/08/2022, 11:40
Axions and axion-like particles are a leading candidate for composing the dark matter in the universe. After reviewing how they emerge in the context of particle physics, we will discuss their production in the early Universe and the prospects for their detection. Interestingly, the distribution of axions is generically expected to be non-homogeneous, and we will discuss how this may lead to...
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Martine Lokken22/08/2022, 14:00
The distribution of baryons in the cosmic web contains a wealth of cosmological and astrophysical information. In particular, measurements of the hot gas in anisotropic structures—such as filaments and superclusters—are important for the census of cosmic baryons. Such localized anisotropic measures can also provide cosmological information beyond two-point statistics and help to constrain...
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Yeinzon Rodríguez García22/08/2022, 14:00
This talk will be divided into two pieces. In the first part of the talk, I will present the generalized SU(2) Proca theory (GSU2P for short). As a modified gravity theory that introduces new gravitational degrees of freedom, the GSU2P is the non-Abelian version of the well known generalized Proca theory where the action is invariant under global transformations of the SU(2) group. New...
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Luis Enrique Padilla Albores22/08/2022, 14:20
In this talk, we explore the possibility of primordial black holes (PBHs) forming from the gravitational collapse of either the structures virialized during reheating (referred as inflaton halos or inflaton clusters), or from the collapse of the central core of these configurations (referred as inflaton stars). We compute the threshold amplitude for the density contrast to undergo this...
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Armando Bernui (Observatorio Nacional)22/08/2022, 14:20
Precise measurements at small angles of the cosmic microwave background (CMB) angular power spectrum (APS), done by the Planck collaboration, have stimulated accurate analyses of the lensing amplitude parameter $A_L$ to confirm if it satisfies the value expected by the flat $\Lambda$CDM concordance model, i.e. $A_L = 1$.
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We discuss a possible excess in the Planck APS not accounted by the... -
Dr Drew Jamieson (Max Planck Institute for Astrophysics)22/08/2022, 14:40
We present a fully differential, field level emulator for large-scale structure formation that is accurate in the deeply nonlinear regime. Our emulator consists of two convolutional neural networks trained to output the nonlinear displacements and velocities of N-body simulation particles based on their linear inputs. Cosmology dependence is encoded in the form of style parameters at each...
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Dr Ippei Obata (Max-Planck-Institute for Astrophysics)22/08/2022, 14:40
Antisymmetric tensor field (two-form field) is a ubiquitous component in string theory and generally couples to the scalar sector through its kinetic term. In this paper, we propose a cosmological scenario that the particle production of two-form field, which is triggered by the background motion of the coupled inflaton field, occurs at the intermediate stage of inflation and generates the...
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Maria Mylova (Ewha Womans University)22/08/2022, 15:00
We examine the validity of the classical approximation of the waterfall phase transition in hybrid inflation from an effective field theory (EFT) point of view. The EFT is constructed by integrating out the waterfall field fluctuations, up to one-loop order in the perturbative expansion. Assuming slow-roll conditions are obeyed, right after the onset of the waterfall phase, we find the...
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Camila Novaes (Instituto Nacional de Pesquisas Espaciais)22/08/2022, 15:00
A new and promising technique for observing the Universe and study the dark sector is the intensity mapping of the redshifted 21-cm line of neutral hydrogen (HI). The Baryon Acoustic Oscillations [BAO] from Integrated Neutral Gas Observations (BINGO) radio telescope will use the 21-cm line to map the Universe in the redshift range $0.127 \le z \le 0.449$, in a tomographic approach, with the...
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Francisco Maion (Donostia International Physics Center)22/08/2022, 15:20Statistical Methods and Tensions in CosmologyPlenary/Parallel talk
Covariance matrices are a fundamental component in the process of constraining physical models from observations, determining the sensibility of the dataset to modifications in the model parameters. However, estimating them correctly presents many challenges; in particular, when computing this quantity using simulations, one must assume a galaxy formation model and a set of fiducial...
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Sébastien Renaux-Petel22/08/2022, 15:20
Identifying the particle content of inflation is one of the most important targets of primordial cosmology. In this respect, how the masses and spins of new particles active during inflation can be read off from the statistical properties of primordial density fluctuations is well understood. However, not when the propagation speeds of the new degrees of freedom and of the...
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Sergio Jorás22/08/2022, 16:10
We investigate the structure of quark stars in the framework of $f(R)=R+\alpha R^2$ gravity using an equation of state for cold quark matter obtained from perturbative QCD, parametrized only by the renormalization scale. We show that a considerably large range of the free parameter $\alpha$, within and even beyond the constraints previously reported in the literature, yield non-negligible...
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Osamu Seto22/08/2022, 16:10Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
We re-examine sterile neutrino dark matter in gauged $U(1)_{B-L}$ model. Improvements have been made by proper inclusion of all relevant processes and tracing the evolution of the number densities of sterile neutrino and extra neutral gauge boson $Z'$. The energy density of $Z'$ turns out to to be much greater than in earlier studies. We revise the space of the viable parameters .
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Mr Tomoya Tachinami (Hirosaki University)22/08/2022, 16:30
We study the polarizations of gravitational waves (GWs) in generic higher-curvature gravity (HCG) whose Lagrangian is an arbitrary polynomial of the Riemann tensor. On a flat background, the linear dynamical degrees of freedom in this theory are identified as massless spin-2, massive spin-2, and massive spin-0 fields. Employing a fully gauge-invariant formalism, we demonstrate that (i) the...
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Alex Soto (Newcastle University)22/08/2022, 16:30Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
We present a finite temperature model for dark matter. In this work, we show coupled equations for self-interacting scalar dark matter which can include both a condensed, low momentum fuzzy component and one with higher momenta that may be described as a collection of classical particles. We do this from first principles, using two distinct but equivalent approaches: firstly via the...
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JOHN BAYRON ORJUELA-QUINTANA (UNIVERSIDAD DEL VALLE)22/08/2022, 16:50
In general, modified gravity theories can be seen as dark energy theories using the effective fluid approach. In this work, we apply this formalism to the most general second-order scalar-vector-tensor (SVT) theory of gravity. This will allow us to encompass all the free functions of the theory in terms of the equation of state, speed of sound, velocity, and anisotropic stress of a very...
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Chee Sheng Fong22/08/2022, 16:50Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
Gravitational production of massive particles due to cosmic expansion can be significant during the inflationary and reheating period of the Universe. In this work, we focus on the gravitational production of light vector bosons that couple feebly to the Standard Model (SM) particles. Due to the very feeble coupling, the light vector bosons never reach thermal equilibrium and if the Hubble...
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Prof. Bivudutta Mishra (BITS-Pilani, Hyderabad Campus)22/08/2022, 17:10
In this paper, we have emphasized the stability analysis of the accelerating cosmological models obtained in $f(T)$ gravity theory. The behaviour of the models based on the evolution of the equation of state parameter shows phantom-like behaviour at the present epoch. The scalar perturbation technique is used to create the perturbed evolution equations, and the stability of the models has been...
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Dr Miguel A. Sánchez-Conde (IFT UAM/CSIC)22/08/2022, 17:10Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
A prediction of the standard LCDM cosmological model is that dark matter (DM) halos are teeming with numerous self-bound substructure, or subhalos. The most massive ones host the observed dwarf satellite galaxies, while smaller subhalos may host no stars/gas at all and thus may have no visible astrophysical counterparts and would remain completely dark. Yet, some of these ‘dark satellites’ are...
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Archisman Ghosh23/08/2022, 09:10Plenary/Parallel talk
The first three observing runs of the LIGO-Virgo-KAGRA detector network have led to 90 detections of compact binary coalescences and have ushered in a wealth of results in fundamental physics, astrophysics and cosmology. In this talk we give a brief overview of the observations and focus on standard-siren cosmology, namely the use of compact binaries as standard distance indicators to measure...
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Bernhard Meirose (Stockholm University (SE))23/08/2022, 09:50Plenary/Parallel talk
The HIBEAM/NNBAR experiment is a two stage experiment for the European Spallation
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Source (ESS) to search for baryon number violation. The experiment would make high sensitivity searches for baryon number violating processes: n → nbar and n → n′(neutron to sterile neutron), corresponding to the selection rules in baryon number ΔB = 2, 1 , respectively. The experiment addresses topical open... -
Jessie Muir23/08/2022, 11:00Plenary/Parallel talk
The Dark Energy Survey (DES) is a 5000 square degree galaxy imaging survey which completed six years of observations in 2019. By measuring the shapes and colors of more than 200 million galaxies in addition to conducting a supernova survey, DES is a multi-purpose experiment that is able to study the large-scale properties of the Universe using measurements of weak gravitational lensing, galaxy...
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Stefano Borgani23/08/2022, 11:40Plenary/Parallel talk
I will review the role that galaxy clusters have as tracers of growth of cosmic structures and to constrain the Dark Sector of the Universe. After overviewing the current state of cluster cosmology, I will show one example of cosmic tension arising when comparing cosmological posteriors derived from galaxy clusters and Lyman-alpha forest. Within this context, I will critically discuss the...
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Dr Felipe Oliveira Franco (University of Oxford)23/08/2022, 14:10
Phase correlations have been proposed as an efficient higher-order statistic able to extract cosmological and astrophysical information that is largely independent from the two-point function or power spectrum. In this talk, we develop an estimator for the line correlation function of projected fields, corresponding to the correlation between the harmonic-space phases of the field at three...
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Clecio R. Bom (Centro Brasileiro de Pesquisas Físicas)23/08/2022, 14:10
The detection of gravitational waves (GW) has opened a new window for cosmology. The current tension between the measurement of the Hubble constant H0 from Cosmic Microwave Background and Supernova analyses makes an independent, standard siren measurement of H0 from gravitational waves particularly interesting.
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However, up to date, the astronomical community has confidently identified only... -
Pedro Carrilho (Queen Mary University of London)23/08/2022, 14:30
I will describe recent developments on the nonlinear modelling of LSS, in the context of momentum-exchange interacting dark energy. I will review the Dark Scattering model and show how it can alleviate the current $S_8$ tension between early and late-Universe data. I will present new constraints on this interaction from a likelihood analysis of the BOSS DR12 power spectrum multipoles, while...
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Josiel Mendonça (Universidade Federal do Rio Grande do Norte)23/08/2022, 14:30
Since the first gravitational wave detection from a merging binary black hole system by the large interferometers LIGO, a new window of the Universe was opened leading us to use these waves to probe the expansion of the Universe. Gravitational wave sources with electromagnetic counterparts, called bright standard sirens, are very useful to cosmology as their luminosity distances can be...
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Matheus Medeiros (Università di Pisa, INFN Pisa)23/08/2022, 14:50
In this talk, I will present a method to extract the Scalar Vector Tensor (SVT) first order perturbations from the Cosmological Perturbations Theory developed in a homogeneous and isotropic Geodesic Light Cone (GLC) background. Due to its adapted light-cone decomposition, the GLC-SVT relation becomes involved, notwithstanding, I will present two different strategies to easy this relation. In...
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Riccardo Sturani (IFT-UNESP/ICTP-SAIFR)23/08/2022, 14:50
We investigate a recently proposed method for measuring the Hubble constant from gravitational wave detections of binary black hole coalescences without electromagnetic counterparts. In the absence of a direct redshift measurement, the missing information on the left-hand side of the Hubble-Lemaître law is provided by the statistical knowledge on the redshift distribution of sources. We assume...
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George Zahariade23/08/2022, 15:10
We study kink-antikink scattering in the sine-Gordon model in the presence of interactions with an additional scalar field, ψ, that is in its quantum vacuum. In contrast to the classical scattering, now there is quantum radiation of ψ quanta and the kink-antikink may form bound states that resemble breathers of the sine-Gordon model. We quantify the rate of radiation and map the parameters for...
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David Marsh23/08/2022, 16:25Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
Axionlike particles (ALPs) are among the most well-motivated extensions of the Standard Model of particle physics, and are increasingly popular dark matter candidates. Extreme astrophysical environments, such as dense and hot supernovae, or vast and magnetised galaxy clusters, provide unique opportunities to test the theory. In this talk, I will discuss recent progress in searching for ALPs...
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Ricardo Zambujal Ferreira23/08/2022, 16:45Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
Axions are often accompanied by discrete symmetries that are
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spontaneously broken in the early universe and lead to the formation of
a network of cosmic domain walls (DW).
In this talk, I will discuss the stochastic gravitational wave (GW)
background produced by such networks. I will show that in some heavy QCD
axion models, the GW signal is within reach of current and future
detectors... -
Moira Venegas23/08/2022, 17:05Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
We study axion dark matter production from a misalignment mechanism in scenarios featuring a general nonstandard cosmology. Before the onset of Big Bang nucleosynthesis, the energy density of the universe is dominated by a particle field $\phi$ described by a general equation of state $\omega$. The ensuing enhancement of the Hubble expansion rate decreases the temperature at which axions start...
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Paul De Jong (Nikhef National institute for subatomic physics (NL))24/08/2022, 09:10Plenary/Parallel talk
We report on the status and latest results of the KM3NeT neutrino telescope in the Mediterranean Sea. KM3NeT has two detectors, KM3NeT/ORCA in France, optimized for the measurement of atmospheric neutrinos, and KM3NeT/ARCA in Italy, focussed on the detection of cosmic neutrinos. Although the detector is still under construction, first results with data using configurations of six lines in ORCA...
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Kate Scholberg24/08/2022, 09:50Plenary/Parallel talk
This talk will provide an overview of neutrinos in physics, astrophysics and cosmology. I will broadly cover detection of neutrinos over a wide range of energies, highlighting several ongoing and future projects.
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Carlos Wuensche24/08/2022, 11:25
The BINGO instrument is being constructed with the goal to be the first radio telescope to detect Baryonic Acoustic Oscillations (BAO) in the radio frequency band (~ 1 GHz) using the 21 cm hyperfine transition of the neutral hydrogen using an observation technique known as intensity mapping (IM). However, the 21 cm signal is a few orders of magnitude weaker than the emission from other...
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Joshua Ziegler24/08/2022, 11:25
Stars whose initial mass is between approximately 150 and 240 M$_\odot$ face a fate of complete explosion in a pair instability supernova (PISN). However, by injecting energy into the star, it may be possible in some cases to avoid this fate. We outline conditions on this energy injection which can lead to the survival or incomplete explosion of the star, and we discuss how dark matter...
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Larissa Santos24/08/2022, 11:45
The 21 cm hydrogen line is arguably one of the most powerful probes to explore the Universe, from recombination to the present times. To recover it, it is essential to separate the cosmological signal from the much stronger foreground contributions at radio frequencies. The Baryon Acoustic Oscillations from Integrated Neutral Gas Observations (BINGO) radio telescope is designed to measure the...
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Andrew Miller (UCLouvain)24/08/2022, 11:45
Gravitational-wave interferometers can be used to probe the existence of dark matter. Different types of dark matter, such as primordial black holes, ultralight boson clouds around spinning black holes, axions and dark photons, could leave different imprints on gravitational-wave detectors. While arising from physically different sources, such gravitational-wave and dark-matter signals share...
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Joao Alberto de Moraes Barretos24/08/2022, 12:05
With the recent development of projects for the gathering of cosmological data through radioastronomy, mainly using the redshifted 21 cm signal line, various systematic effects have been analysed to improve sensibility and precision. This includes instrumental features such as beam analysis, which involves studying the how the reflectors modify the data through optical aberrations, and how it...
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Isabel Lopes25/08/2022, 09:10Plenary/Parallel talk
The nature of dark matter is one of the outstanding open questions in physics. Although the observational evidence for the existence of a non-baryonic, non-luminous and non-relativistic component of the universe has been strengthen in recent years, its nature still remains unknown. A class of theoretically-motivated non-relativistic particles with masses approximately in the GeV to TeV range,...
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Gonzalo Palma25/08/2022, 09:50Plenary/Parallel talk
I will review recent progress to address the generation of primordial non-Gaussianity during cosmic inflation. I will focus my attention on the origin of non-Gaussian signals that are poorly parametrized by the bispectrum (the three-point function). Such non-Gaussian deformations of the statistics may be crucial to understand the generation of primordial black holes, and necessarily require...
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Ki Young Choi25/08/2022, 11:00
I will review the status of the dark matter theory and phenomenology.
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Gabriele Franciolini25/08/2022, 11:40
Primordial Black Holes might comprise a significant fraction of dark matter in the Universe and can give rise to observable signatures at current and future gravitational wave experiments. First, we review the PBH model and discuss how accretion and clustering may affect the properties of PBH binaries. Second, we confront the PBH model with LIGO/Virgo/KAGRA data showing its upsides and...
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Chiara Moretti (University of Edinburgh)25/08/2022, 14:00Plenary/Parallel talk
Future generations of galaxy redshift surveys will sample the large-scale structure of the Universe over unprecedented volumes with high-density tracers, allowing for precise measurements of the clustering statistics. In order to properly exploit the full potential of such data, a robust likelihood pipeline is required, starting with an accurate theoretical prediction of cosmological...
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Spyros Sypsas25/08/2022, 14:00
New degrees of freedom active during inflation lead to nontrivial signatures across scalar and tensor primordial spectra. We will discuss how such deviations from single-field, slow-roll inflation, manifested as particle excitations, lead to distinct signals in the stochastic gravitational wave background generated during inflation and how its characteristics are related to sharp features of...
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Juan Calderon Bustillo (University of Santiago de Compostela)25/08/2022, 14:20
Boson-stars are self-gravitating Bose-Einstein condensates of ultra-light boson fields, which are widely considered as strong candidates to account for at least part of Dark Matter. Boson-star mergers can produce gravitational-wave signals observable by current detectors such as Advanced LIGO and Virgo. I will present a systematic comparison of existing (high-mass) gravitational-wave signals...
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Prof. Ronaldo C Batista (Federal University of Rio Grande do Norte)25/08/2022, 14:20
We study the spherical collapse of non-top-hat matter fluctuations in the presence of dark energy with arbitrary sound speed ($c_s$). The model is described by a system of partial differential equations solved using a pseudo-spectral method with collocation points. This method can reproduce the known analytical solutions in the linear regime with an accuracy better than $10^{-6}$ % and better...
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Carlos Melo (IF/UFRGS)25/08/2022, 14:40
General Relativity (GR) has been successfully tested mainly at Solar system scales; however, in the last few decades, galaxy-scale tests have become popular. In particular, some recent works dedicate close attention to the $\eta_{\text{PPN}}$ parameter, which is commonly associated with the spatial curvature generated per unit mass. Under the assumption of GR, and a vanish anisotropic stress...
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Hajime Sotani25/08/2022, 14:40
The supernova, which is the event at the last moment of the massive star's life, is the next promising candidate as the gravitational wave source. Up to now, gravitational waves from supernova explosions have been mainly discussed via numerical simulation. These results tell us the existence of the gravitational waves whose frequencies increase from a few hundred hertz up to kHz within a...
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Kunihito Uzawa (Kwansei Gakuin University)25/08/2022, 15:00
The Gibbons-Maeda-Garfinkle-Horowitz-Strominger (GMGHS)
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black hole is an influential solution of the low energy heterotic
string theory. As it is well known, it presents a singular extremal
limit. We construct a regular extension of the GMGHS extremal black
hole in a model with $\mathcal{O}(\alpha')$ corrections in the action,
by solving the fully non-linear equations of motion.... -
Dr Vicharit Yingcharoenrat (Kavli IPMU, Tokyo)25/08/2022, 15:00
In this talk I will present the formulation of the Effective Field Theory (EFT) of black hole perturbations within scalar-tensor theories on an inhomogeneous background. In particular, the EFT is constructed while keeping a background of a scalar field to be timelike, which spontaneously breaks the time diffeomorphism. I will then discuss a set of consistency relations that are imposed by the...
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Davi Rodrigues (Universidade Federal do Espirito Santo)25/08/2022, 15:20
I will introduce a fast and complementary approach to study galaxy rotation curves directly from the sample data, instead of first performing individual rotation curve fits. The method is based on a dimensionless difference between the observational rotation curve and the expected one from the baryonic matter ($\delta V^2$). It is named as Normalized Additional Velocity (NAV). Using 153...
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Benjamin Lehmann (UC Santa Cruz)25/08/2022, 16:10Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
Superconducting nanowires, a mature technology originally developed for quantum sensing, can be used as a target and sensor with which to search for dark matter interactions with electrons. We leverage recent developments in the theory of dark matter interactions in dielectrics to robustly predict the event rate in a nanowire device, fully accounting for the many-body physics of the detector....
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Carza Bengaly (Observatório Nacional)25/08/2022, 16:10
The standard cosmological model, namely the flat LCDM model, has been tremendously successful in describing cosmological observations for over two decades. Still, it suffers from theoretical caveats, in addition to recent problems like the SH0ES tension between H0 measurements from the early- and late-time Universe. In light of these issues, I will show results of some null tests of...
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Dr Rodrigo von Marttens25/08/2022, 16:30
We perform a general test of the ΛCDM and wCDM cosmological models by comparing constraints on the geometry of the expansion history to those on the growth of structure. Specifically, we split the total matter energy density, Ωm , and (for wCDM) dark energy equation of state, w, into two parameters each: one that captures the geometry, and another that captures the growth. We constrain our...
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Antonino Troja25/08/2022, 16:30Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
The Euclid space-based survey will observe and map the distribution of galaxies with unprecedented accuracy, allowing us to improve the knowledge of the Universe and its dynamics as well as the nature of the so-called dark matter that contributes up to a quarter of the total energy density of the Universe. Furthermore, key research will involve the measurements of the subtle features produced...
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Joran Angevaare25/08/2022, 16:50Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
The evidence for dark matter is overwhelming, yet there has not been an unambiguous detection of a dark matter particle. The XENON collaboration has operated successively larger experiments in the hunt for WIMP-dark matter using dual phase time projection chambers with xenon as the target material. The XENON collaboration is one of the leading collaborations in constraining the WIMP-nucleon...
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Pedro da Silveira Ferreira (UFRJ)25/08/2022, 16:50
We test the usual hypothesis that the Cosmic Microwave Background (CMB) dipole, its largest anisotropy, is due to our peculiar velocity with respect to the Hubble flow by measuring independently the Doppler and aberration effects on the CMB using Planck 2018 data. We remove the spurious contributions from the conversion of intensity into temperature and arrive at measurements which are...
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Jinn-Ouk Gong25/08/2022, 17:10Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
A kinetic coupling between the photon and a dark photon, a massless U(1)-gauge boson in the dark sector, transfers dark photon’s birefringence to observed cosmic birefringence. Regardless of the origin of the dark birefringence, the amplitude and unique frequency-dependence of the cosmic birefringence depend on the kinetic-coupling constant and the dark-photon temperature. To explain the...
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Frank Qu (University of Cambridge)25/08/2022, 17:10
Dark matter not only provides the invisible scaffolding from which the birth of galaxies takes place, but by studying its distribution in our Universe we can infer a great deal of information regarding the growth of structure and cosmic expansion. Measuring the gravitational lensing of the CMB allows the mapping of all the matter distribution (for which the majority is dark matter) to very...
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Júlio Fabris (UFES)25/08/2022, 19:00Plenary/Parallel talk
Em 1922 o matemático russo Alexander Friedmann publicou o artigo em que pela primeira vez na história se evocava a possibilidade que o universo fosse dinâmico e pudesse estar em expansão. A expansão do universo seria pouco depois confirmada pelas observações. Desse momento em diante, o moderno modelo cosmológico foi sendo paulatinamente construído. Hoje ele se alicerça sobre vários sólidos...
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Domenico Sapone26/08/2022, 09:10Plenary/Parallel talk
The Euclid survey will map the large scale structure with the aim of measuring the parameters of the standard cosmological model with unprecedented precision.
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However, the great sensitivity of Euclid can also be exploited to test the most fundamental assumptions at the basis of the standard cosmological model. Here we present two works of the Euclid Consortium where, forecasts from Euclid... -
Elena Sellentin26/08/2022, 09:50Plenary/Parallel talk
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Carlos Hernandez-Monteagudo26/08/2022, 11:00Plenary/Parallel talk
The J-PAS (Javalambre Physics of the Accelerating Universe Astrophysical Survey) scans the sky through 56 narrow band (~140 Å) + 3 broad band optical filters that render a R~50 spectra of every object detected in the footprint. The first square degree covered by the miniJPAS survey has produced \sigma_{NMAD}<0.005 x (1+z) for most galaxies with r<22.5, thus enabling an accurate reconstruction...
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Tiago Castro (INAF-OATS)26/08/2022, 11:40
The next galaxy cluster survey has the potential of being a very competitive cosmological probe. The main cosmological inference done with clusters is the so-called number counts, within which the halo mass function (HMF) is a vital theoretical quantity. This talk revises the calibration of the HMF, focusing on the numeric and theoretical systematic effects from the simulation’s purely...
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Perseas Christodoulidis26/08/2022, 14:00
We explore observational signatures from multi-field inflationary models with more than two fields. We first revisit the two-field case where the attractor solution with either small or large turn rate can be found analytically and investigate under what conditions the same procedure can be generalised for more fields. For three fields in the slow-roll, slow-twist and extreme turning regime we...
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Sarah Geller (MIT)26/08/2022, 14:00Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
Primordial Black Holes (PBHs), first postulated more than half a century ago, remain an active and fascinating area of research and provide an exciting prospect for accounting for Dark Matter. In this talk I will discuss the possibilities for production of PBHs near to Dark Matter mass scales from realistic multi-field inflation models that arise naturally from supergravity. These models fit...
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Nelson Pinto-Neto26/08/2022, 14:20
The problem of finding a vacuum definition for a single quantum field in curved spaces is discussed under a new geometrical perspective. The minimum complex structure in phase space necessary to define a vacuum state is mapped to a 2-dimensional hyperbolic space in which distances can be defined. It is shown that well known vacuum prescriptions in the literature correspond to points in this...
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Dr M. Sten Delos (Max Planck Institute for Astrophysics)26/08/2022, 14:20Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
Through their observable properties, the first and smallest dark matter halos represent a rare probe of subkiloparsec-scale variations in the density of the early Universe. These density variations could hold clues to the nature of inflation, the postinflationary cosmic history, and the identity of dark matter. The first halos are understood to possess a uniquely compact central mass...
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Prof. Marcos A. Garcia Garcia (Instituto de Fisica, UNAM)26/08/2022, 14:40Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
The production of dark relics from the decay of the primordial inflaton condensate must always be considered when building models of the very early Universe. Even in the absence of direct couplings, dark matter and radiation can be produced from the gravitational interaction between the dark and inflaton sectors. In this talk I will discuss the non-equilibrated production of scalar dark matter...
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Dr César Peralta (Universidad Antonio Nariño)26/08/2022, 14:40
In this work we analyze the stability criteria in $f(R)$ theories of gravity in the metric formalism under the approach of a thermodynamics analogy proposed in [C.D. Peralta and S.E. Jorás JCAP06(2020)053] for $\phi^4$ and double well inflationary potentials. We starting from the mentioned potentials in the Einstein frame, and obtain a parametric form of $f(R)$ in the corresponding Jordan...
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João Paulo França (CBPF)26/08/2022, 15:00
Gravitational arcs are strongly magnified images of distant galaxies (known as sources) caused by the deflection of light produced by a foreground galaxy or galaxy cluster (the lens). This strong lensing phenomenon has been used to study high-redshift sources, to assess the mass distribution in the lens, to constrain cosmological parameters and to set limits on modified gravity. In addition,...
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Leszek Roszkowski26/08/2022, 16:05
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Eduardo Fraga (Instituto de Física, UFRJ)26/08/2022, 16:35Dark matter, neutrinos & astroparticle physicsPlenary/Parallel talk
We discuss compact stars consisting of cold quark matter and fermionic dark matter treated as two admixed fluids. After the computation of the stellar structure and fundamental radial oscillation frequencies for different masses of the dark fermion in the cases of weak and strong self-interacting dark matter, we show that the fundamental frequency can be dramatically modified and, in some...
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Aritra Kumar Gon (Tata Institute of Fundamental Research)26/08/2022, 16:35
We study the E and B mode polarisation of the cosmic microwave background (CMB) originating from the transverse peculiar velocity of free electrons during reionisation and post reionisation era. Interestingly, apart from having a blackbody part, the spectrum also contains a Sunyaev Zel'dovich (SZ) type (y-type) distortion, which makes it distinguishable from primordial polarisation as well as...
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Simón Riquelme (Universidad de Chile)26/08/2022, 16:55
We address the issue of black hole scalarization and its compatibility with cosmic inflation and big bang cosmology from an effective field theory (EFT) point of view. In practice, using a well-defined and healthy toy model which (in part) has been broadly considered in the literature, we consider how higher-order theories of gravity, up to cubic operators in Riemann curvature, fit within this...
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Louis Legrand26/08/2022, 16:55
In this talk I will introduce a new CMB lensing power spectrum estimator for deep polarisation surveys. Thanks to the B modes of polarisation produced by gravitational lensing, upcoming surveys will optimally reconstruct the lensing field by iteratively delensing the observed polarisation maps. I will show that despite the increased complexity of the reconstructed lensing map, its power...
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Jibran Haider (University of Toronto, Canadian Institute for Theoretical Astrophysics (CITA))Statistical Methods and Tensions in CosmologyPlenary/Parallel talk
The detection of non-Gaussianity in primordial perturbations offers monumental new information about the early Universe. All models of inflation predict at least some level of primordial non-Gaussianity, and many models result in potentially observable non-Gaussian signatures. While detection efforts thus far have not found any significant primordial non-Gaussianity, they are not sensitive to...
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Anoma Ganguly (TIFR Mumbai)Plenary/Parallel talk
We propose a new solution to explain the anomalous absorption feature detected by the EDGES collaboration in the 50-100 MHz range, using a new millicharged dark matter model, taking into account the existing cosmological and astrophysical constraints. We predict new unique signals to test our dark matter model with future cosmological surveys.
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Thomas Morrison (University of Toronto, Canadian Institute for Theoretical Astrophysics)
The generation of non-Gaussianity during inflation is often viewed in the context of perturbative processes producing small amounts of non-Gaussianity correlated with an underlying Gaussian field. However, there exist physical mechanisms by which non-Gaussianity can be produced non-perturbatively and in novel forms which are poorly modeled by the data templates used in current analysis. We...
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Victor David Bosca Navarro (Institute for Theorerical Physics (IFT) UAM-CSIC)Plenary/Parallel talk
Microlensing of extragalactic sources, in particular the probability of significant amplifications, is a potentially powerful probe of the abundance of compact objects outside the halo of the Milky Way. Accurate experimental constraints require an equally accurate theoretical model for the amplification statistics produced by such a population. In this article, we argue that the simplest...
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Javier Silva Lafaurie (Leiden)
I present a fully Bayesian MCMC-based signal extraction technique, which also solves the E/B-leakage problem for Stage-IV Surveys caused by their partial sky coverage. For cosmic shear, classical analyses lose information cutting off small scales because the noise dominates its signal, and additionally large scales as a result of the leakage between E and B modes. Our code Almanac allows us to...
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Franciele M. da Silva (Universidade Federal do Espírito Santo)Poster
The big open questions we still have currently in the fields of gravitation and cosmology, such as the dark matter and dark energy problems, among other reasons, have led to the development of many modified theories of gravity. These theories need to be tested in various scenarios to see whether they solve the problems they try to solve. Neutron stars are one of the best astrophysical...
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19. Baryogenesis and Cosmological Consequences of Hořava-Lifshitz Gravity with Starobinsky PotentialGargee Chakraborty (Amity University, Kolkata)Plenary/Parallel talk
In the late 90’s, Reiss et al. [1] and Perlmutter at al. [2] by taking the Supernovae 1a independently proved that the universe is passing through an accelerated expansion. Many observations have supported this accelerated expansion of the late time universe [1,2,3,4,5]. The biggest mystery in the early universe is the production of excess of matter over antimatter [6,7,8. The present study...
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Ms Tiago MourãoPlenary/Parallel talk
We present results regarding the applicability of Gravitational Baryogenesis for bouncing cosmologies generated by quantum effects represented by a Wheeler-DeWitt equation, interpreted according to the de Broglie-Bohm theory. In the context of minisuperspace models, we show that it is possible to obtain the correct baryon asymmetry observed in the Universe, for large regions in the parameter...
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Ranier SilvaPoster
In an age of large astronomical datesets and severe cosmological tensions, the case
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for model independent analyses is compelling. We present a set of 14 baryon acoustic oscillations measurements in thin redshift shells with 3% precision that were obtained by analyzing BOSS DR12 and eBOSS DR16 galaxies in the redshift range 0.32 < z < 0.66. Thanks to the use of thin shells, the analysis is... -
Mrs Daniela Grandón (University of Chile)Poster
Neural nets have become popular to accelerate parameter inferences, especially for the upcoming generation of galaxy surveys in cosmology. As neural nets are approximative by nature, a recurrent question has been how to propagate the neural net’s approximation error, in order to avoid biases in the parameter inference. We present a Bayesian solution to propagating a neural net’s approximation...
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Piero Molinari (Centro Brasileiro de Pesquisas Físicas (CBPF))Poster
In the framework of the Brans-Dicke scalar-tensor theory of gravitation, we investigate the role of a self-interacting fermionic field in an FLRW universe filled with dust and radiation constituents. This model is shown to present a variety of qualitative behaviors, depending on the numerical parameters chosen. In particular, we find that the fermionic field is capable of promoting a...
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Silvan Fischbacher (ETH Zurich)Plenary/Parallel talk
Intrinsic alignment (IA) modelling and photometric redshift estimation are two of the main sources of systematic uncertainty in weak lensing surveys. We investigate the impact of redshift errors when using different IA models. We show that both errors on the mean of the redshift bin $\delta_z$ and errors of the width of the redshift bin $\sigma_z$ can lead to biases in cosmological...
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Andreas Nygaard (Aarhus University)Plenary/Parallel talk
As numerical complexities of cosmological models are increasing in recent years, so too are the demands for resources when computing solutions to the Einstein-Boltzmann equations with codes like \textsc{class} and \textsc{camb}. A solution to this demand is, of course, more computational power through increasingly better and faster hardware, but perhaps another and more sustainable approach is...
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Isabela Santiago de Matos
It has been shown in the literature that detections of gravitational waves (GWs) emitted by binary sources can provide measurements of luminosity distance. The events followed by electromagnetic counterparts are, then, suitable for probing the distance-redshift relation and doing cosmological parameter estimation, as well as investigating modified gravity models. In the context of the...
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Pablo MottaPoster
A recent project which aims to understand dark energy properties is the BINGO Telescope: an Intensity Mapping instrument designed to measure BAO in the radio band, through the measurement of the 21cm line of emission. In this work we present cosmological forecasts for BINGO by the nested sampling Monte Carlo method. This method is more robust and reliable, although more computationally...
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Nameeqa Firdous (GIFT University Gujranwala Pakistan)Poster
We studied the four models implemented in PYTHIA8 for the production of dark matter or associated particles at the LHC based on the simplest extensions of the Standard Model. The first model includes dark matter production via s-channel mediators. This includes production in association with a jet for a vector boson or scalar mediator. Aside from the standard simplified models where the dark...
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Emil Brinch HolmPlenary/Parallel talk
During the recent years, decaying dark matter models have received renewed interest as proposed solutions to the current cosmological tensions, mainly due to their flexible expansion histories and clustering properties. While much focus has been on decaying cold dark matter, in this talk, I will present our recent work on decaying warm dark matter based on our recent preprint arXiv:2205.13628....
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Nilanjandev Bhaumik (Indian Institute of Science, Bengaluru)Plenary/Parallel talk
Primordial black hole (PBH) has come up as a very promising cold dark matter candidate in recent years. The signature of PBHs in the gravitational wave background is expected as PBH formation requires a large amplfication in inflationary scalar curvature perturbation, which sources the tensor perturbation in second-order and leads to a detectable amplification in the gravitational wave (GW)...
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Prof. Umpei Miyamoto (Akita Prefectural University)
It is interesting to know whether or not we can determine black-hole's parameters such as the mass, spin, inclination angle, and distance only from the information of black-hole's shadow. In this work, assuming a non-spinning black hole, i.e., a Schwarzschild black hole, with an infinitely thin accretion disc for simplicity, we show that the system's parameters such as the angular...
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Jose Tomas Galvez Ghersi (Canadian Institute for Theoretical Astrophysics)
Oscillons are localized field configurations oscillating in time with lifetimes orders of magnitude longer than their oscillation period. This talk shows the deformation of one-dimensional breather solutions of the sine-Gordon (SG) equation into oscillons. SG equation is deformed by a radial damping term present in the d-dimensional Laplacian. Oscillons are evaluated (a) in a regime of...
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Phearun Rithy (Royal University of Phnom Penh)Plenary/Parallel talk
We consider an extension of the novel 4D Einstein-Gauss-Bonnet (EGB) gravity by proposing a coupling between the scalar field and the Gauss-Bonnet term, which is otherwise absent in the novel 4D EGB theory, and demonstrate that the additional contributions to the equations of motion come from both the scaling of a coupling constant and the non-minimal coupling between the scalar field and...
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Alexsandre Leite Ferreira Junior (UFES)Plenary/Parallel talk
Several physical systems of interest in cosmology, such as the Lovelock extension of general relativity in higher dimensions, k-essence fields, Horndeski theories, and nonlinear electrodynamics, have apparent ill-defined sympletic structures, due to the fact that their Hamiltonians are multivalued functions of the momenta. In this talk, based on the paper [PRD 105, 084064 (2022)], the...
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Nitin Joshi (IIT Ropar)Plenary/Parallel talk
We consider a minimally massless coupled quantum scalar field with an asymmetric (quartic plus cubic) self interaction, V (φ) = λφ^4/4!+βφ^3/3! in the (3 + 1)-dimensional inflationary de Sitter background. This potential is bounded from below regardless the sign of β. The motivation of this study comes from the fact that such a potential may generate negative vacuum expectation value of V(φ)...
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SANTIAGO GARCIA SERNAPlenary/Parallel talk
We studied a dark energy (DE) model with tachyonic fields coupled to a vector field in a Bianchi-I anisotropic background. Then, the dynamical analysis of the differential equations was made using a Monte Carlo approach in the parameters space, in order to restrict the physically allowed regions having anisotropic DE as an attractor. Next, the boundary of the region was fitted, that was how we...
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Alexander Reeves (ETH Zurich)Plenary/Parallel talk
Early dark energy (EDE) alleviates the H_0 tension at the cost of increasing the clustering amplitude and worsening the $S_8$ discrepancy. Motivated by massive neutrinos' ability to suppress structure, we study their impact on EDE combining Planck and BOSS full-shape clustering data. A Bayesian analysis returns no evidence for a non-zero neutrino mass sum $M_{\nu}$ ($<0.15,{\rm eV}$ at...
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Luiz Garcia (uerj)Plenary/Parallel talk
Einstein-Cartan magnetogenesis are investigated in two cases: i) First in the case of torsion suppression in Brans-Dicke inflation. ii) in the second, Einstein-Cartan-Holst magnetogenesis is investigated. In the first case axion dark matter is investigated with axion-torsion transmutation.
references: 1. L C Garcia de Andrade, Topoçogical defects in Einstein-Cartan magnetogenesis and dynamo...
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Miguel Peñafiel RamirezPlenary/Parallel talk
Demanding the validity of the Generalized Second Law implies the existence of entropy bounds. By considering the absorption of matter from arbitrarily close to the horizon, Bekenstein and collaborators derived a universal entropy bound valid for any charged, rotating distribution of matter (including the Kerr-Newman black hole); and, based on the no-hair conjecture, argued that this bound...
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Vicente Albendea, Juan Francisco Not SuppliedPlenary/Parallel talk
In this talk I will show how the Expansion Lensing relationship d_L=d_A(1+z) is derived from the Friedmann-Lemaître-Robertson-Walker (FLRW) metric. The expression also follows from the fact that the angular distance of a galaxy (d_A=S/theta), i.e. the distance at emission, is defined identically for both static and expanding universes, and hence both images subtend the same angle theta....
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Matteo Esposito (Max Planck Institute for Extraterrestrial Physics)Plenary/Parallel talk
By choosing a suitable set of cosmological parameters, one can classify them into two groups with respect to their impact on the linear matter power spectrum $P_\mathrm{L}(k)$ when it is expressed in Mpc units: the evolution parameters, $\Theta_\mathrm{e}$, which determine its amplitude at a given redshift and the shape parameters, $\Theta_\mathrm{s}$, which only affect its shape. This...
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Gabriel Hoerning (University of São Paulo)Plenary/Parallel talk
Fast Radio Bursts (FRBs) are a relatively recent discovered object in cosmology and astrophysics, whose origin is still an open problem. They are a class of brief ($\sim$ ms) and bright ($\sim$ Jy) radio transients that have been detected by a number of radio telescopes around the globe. There is a new generation of radio telescopes coming online, such as the BINGO, CHIME, SKA and others,...
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François LANUSSEStatistical Methods and Tensions in CosmologyPlenary/Parallel talk
In order to prepare for the upcoming wide-field cosmological surveys, large simulations of the
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Universe with realistic galaxy populations are required. In particular, the tendency of galaxies
to naturally align towards overdensities, an effect called intrinsic alignments (IA), can be a
major source of systematics in the weak lensing analysis. As the details of galaxy formation
and... -
Mr Elismar Lösch (IAG-USP), Dr Laerte Sodré (IAG-USP)Poster
At scales of dozens of Mpcs, the galaxy distribution forms the cosmic web. Galaxy clusters occupy its nodes and are connected to other nodes by vast filamentary chains of galaxies and groups of galaxies. In this work we are investigating some nearby superclusters and filaments in the southern skies. We use the high-precision photometric redshifts obtained in the 12 band S-PLUS photometric...
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João Cavedagne Lobato (Universidade Federal do Rio de Janeiro)Plenary/Parallel talk
In this work, we generalize to a viable Horndeski theory of gravity, the most general scalar-tensor theory that has second-order field equations in four dimensions, the expression of a statistically homogeneous and unpolarized stochastic gravitational wave background signal measured as the correlation between the individual signals detected by two not coincident and not coaligned GW...
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Dr Philipp Mauritz Klose (Bern University)
If a pseudoscalar inflaton couples to the topological charge density of a non-Abelian gauge field, it can decay into gauge bosons that may thermalize quickly due to their self-interactions. In the resulting medium, non-Abelian ``strong sphaleron'' interactions increase the thermal friction felt by the inflation field, which can in turn lead to a self-amplifing and efficient reheating after...
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Dr Igor Chernykh (Siberian Supercomputer Center ICMMG SB RAS)Poster
Astrochemistry plays an important role in the most of astrophysical processes on all stages of the universe life. Unfortunately, the most of the chemical processes can't be simulated in labs because of the physical conditions. We will show our latest high-performance computing code for numerical simulation of astrochemical problems. This code can be used as standalone application for...
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Victor Robles (Yale University)Plenary/Parallel talk
The well-known small-scale discrepancies between the observed satellite abundance in the Local Group and predictions from Cosmological simulations in CDM seems to point to missing physics in our models. This new physics may be a different dark matter nature beyond the standard WIMP candidate. In my talk I will discuss how the internal structure and increasing discoveries of fainter galaxies...
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George Fanaras
We study quantum cosmology of the 2D Jackiw-Teitelboim (JT) gravity with Λ > 0 and calculate
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the Hartle-Hawking (HH) wave function for this model in the minisuperspace framework. Our
approach is guided by the observation that the JT dynamics can be mapped exactly onto that of
the Kantowski-Sachs (KS) model describing a homogeneous universe with spatial sections of S1×S2
topology. This... -
Mr Ayodeji Ibitoye (University of KwaZulu Natal)Poster
We present a joint analysis of the power spectra of the Planck Compton y-parameter map and the projected galaxy density field using the WISE all-sky survey. We detect the statistical correlation between WISE and Planck data (gy) with a significance of 21.8σ. We also measure the auto-correlation spectrum for the tSZ (yy) and the galaxy density field maps (gg) with a significance of 150σ and...
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Pedro BessaPlenary/Parallel talk
Horndeski Gravity is the most general 2nd order scalar-tensor theory in 4 dimensions. This theory contains well known
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modified Gravity Theories such as k-essence, f(R) and Galileon Gravity.
In this work we aim to derive the lens map and related quantities such as the time delay in the framework of Horndeski gravity in general spacetimes, and more specifically in the case of a point lens in a... -
Juan Manuel Gonzalez (Instituto Balseiro-CONICET)Poster
Magnetic fields present in the Universe and interactions with the cosmic radiation backgrounds play an important role shaping the flux of the ultrahigh energy cosmic rays. To account for both processes we include in the SimProp cosmic ray propagation code a routine to follow the direction of propagation of the particles in a turbulent magnetic field. We compute thus the modification of the...
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Rodrigo Lipparelli FernandezPlenary/Parallel talk
We study the tunneling probability of a massive ($m_w$) uncharged scalar packet out from a near-extremal, static charged black hole (with mass $M$ and charge $Q \to M^+$). We show that there is indeed a \textit{net} probability that a massive uncharged particle tunnels out from the black hole so that the final state (with new mass $M'\equiv M-m_w < Q$) does violate the cosmic censorship...
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Fabio van Dissel (IFAE)Plenary/Parallel talk
Oscillons are oscillating, localized configurations in real scalar field theories. They appear in potentials that are shallower than quadratic away from the minimum and can be extremely long-lived.
Since plateau models are of great relevance for inflation, oscillons have been shown to form efficiently during preheating in a wide range of such models. Their formation and decay are...
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Isidro Gómez Vargas (Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México)Plenary/Parallel talk
Artificial neural networks can model nonlinear relationships in datasets. In observational cosmology there are many situations involving complex datasets, therefore in this talk we present some applications of neural networks in the framework of cosmological data analysis. We use observational data and numerical simulations; the tasks we have tackled with neural networks have been...
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Saikat Chakraborty (North-West University)Plenary/Parallel talk
Dynamical system formulation is an important qualitative tool now widely used in
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cosmology to understand the cosmological solution space of a theory. A number of
dynamical system formulations have been proposed over the last few years to analyse
cosmological solutions in f(R) gravity. I will try to give a brief introduction to the
di↵erent approaches, presenting them in a chronological... -
Prof. Abdel Nasser Tawfik (ECTP)Plenary/Parallel talk
When generalized noncommutative Heisenberg algebra accommodating gravitational field as specified by string theory, for instance, is thoughtfully applied on Finsler manifold, the quantized metric tensor could be defined. By constructing the affine connections on pseudo--Riemannian manifold, quantization of Riemann curvature tensor and its unique contractions, Ricci curvature tensor and scalar,...
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Arthur Camara Mesquita
In the geometric optics regime gravitational lensing is an achromatic phenomenon. However, certain physical situations require wave optics to be taken into account, such that the deflection angle becomes wavelength dependent and the interference between multiple images must be taken into account. These effects are particularly relevant in the case of lensing by low mass compact objects, such...
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Dan Vagie
Phase Transitions as Cosmological Witnesses
4 May 2020, 15:15
15m
Parallel Talk Cosmology Cosmology I
Speaker
Dan Vagie
DescriptionWe study the gravitational wave background from a first order phase transition generated during standard and nonstandard cosmological histories. We analyze the hydrodynamic properties of the plasma to define a self-similar invariant velocity profile to be...
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Prof. Alessandro Spallicci (Université d'Orléans - CNRS)Plenary/Parallel talk
Astrophysical observations are largely based on electromagnetic signals still read with the Maxwellian massless and linear theory, possibly an approximation of a larger theory, as Newtonian gravity is for Einsteinian gravity in weak fields. Photons are the sole free massless particles in the Standard-Model (SM). Apart from massive formalisms (de Broglie-Proca, Bopp, Stueckelberg and others),...
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LUCAS Fontana Formigari (Universidade de São Paulo)Poster
Black Holes with masses of the order of $10^{14}$g would be evaporating today, which could have been formed in the beginning of the universe. On the other hand, Fast Radio Bursts are thought to be associated to compact objects with extreme magnetic fields. Starting from V. Manko's solution of the Einstein Equations for a Rotating Black Hole with a magnetic field, it's emission properties are...
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Marcelo Rebouças (CBPF)Poster
Orientability is an important topological property of spacetime manifolds. It is widely believed that spatial orientability can only be tested by global journeys around the Universe to check for orientation-reversing closed paths. Since such global journeys are not feasible, theoretical arguments that combine universality of physical experiments with local arrow of time, CP violation and CPT...
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Louis LegrandPlenary/Parallel talk
In the context of next generation galaxy surveys, new statistics of the distribution of matter are being developed. Among these, I will present the Angular Redshift Fluctuations (ARF), which keep some of the information contained in the density fluctuations of galaxies along the line of sight into an angular summary statistics. I will show how the ARF are sensitive to the peculiar velocities...
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George ZahariadePlenary/Parallel talk
In a series of papers with Maulik Parikh and Frank Wilczek we study the effect of a quantized gravitational wave on a LIGO-type gravitational wave detector. We find that the arm-length is subject to a stochastic tidal force whose properties depend on the exact quantum state of the gravitational field, if the gravitational field is quantized. The quantum nature of gravity may thus be detectable...
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Sina HooshangiPlenary/Parallel talk
In recent years, it has been noted that perturbative treatment of large fluctuations fails to make correct predictions, e.g., for the formation of primordial black holes. Some non-perturbative methods like stochastic formalism were introduced to explore the tail of distributions, resulting in exponential tails for probability distributions in some models when quantum kicks dominate the...
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Mr Luis Escamilla (ICF, UNAM)Plenary/Parallel talk
The problems with the stantard model of cosmology $\Lambda$CDM are well-known, such as the origin and behaviour of Dark Matter and Dark Energy or some tensions with the inferred value of some parameters when using distinct data sets, and several solutions have been proposed. One approach to try and elucidate the nature of the Dark Energy and relieve the parameter tensions is through...
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Amanda Santos (University of Sao Paulo)Poster
Spectroscopic redshifts ($z$) are obtained through the spectra of astronomical objects, this process is time-consuming, expensive, and frequently impossible for large numbers of galaxies due to telescope time limitations. Thus, in order to find this parameter $z$, in this work, we use the photometry of galaxies to determine this same quantity. Photometric redshifts can be evaluated through the...
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Dr Marcos A. Garcia Garcia (Instituto de Fisica Teorica UAM)Plenary/Parallel talk
In the first stages of inflationary reheating, the mean energy of the radiation produced by inflaton decay is higher than the commonly defined reheating temperature. In thermal equilibrium, particle production can then be significantly enhanced relative to the subsequent radiation dominated era. Furthermore, in the earliest stages of reheating, before thermalization takes place, scattering of...
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Miguel EnriquezPlenary/Parallel talk
We implement relativistic corrections to the evolutions of dark matter structures in Newtonian simulations of a LCDM universe via the initial conditions. We show how fNL and gNL contributions can be introduced consistently in the same fashion. We implement such corrections to the L-PICOLA code and compute the power spectrum and bispectrum of the evolved matter field. Our results confirm that...
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Eunice OmwoyoPlenary/Parallel talk
This work is geared towards analysis of shadows cast by Kerr-de Sitter (kds) and Revisited Kerr-de Sitter (RKdS) black holes. Considering observers in the vicinity of the static radius, we derive the impact parameters defining the apparent positions of the shadows. Such observers are of interest to our work because embedding diagrams have shown that de Sitter space-time is analogous to an...
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Kenza ZEGHARI (Aix-Marseille University)
I will talk about Bianchi cosmologies coupled to a matter source that has the field theoretical description of a solid. Models of solid inflation are known for not being very efficient in diluting away anisotropy. While confirming this fact, our study finds another potential feature of solid inflation, namely a ``rotation” of the principal axes of the expansion. Such a rotation is not just a...
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Nathan J. Carlson (CITA/University of Toronto)
All models of inflation predict some non-Gaussian signatures in the cosmological distribution of energy, the search for which is a subject of great importance to our understanding of the early universe. In this work, we present simulated sky maps for a novel extended stochastic inflation model that is motivated by an ambitious suite of high-accuracy lattice simulations of early-universe field...
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Keir Rogers
The fundamental nature of dark matter so far eludes direct detection experiments, but it has left its imprint in the large-scale structure (LSS) of the Universe. Extracting this information requires accurate modelling of structure formation and careful handling of astrophysical uncertainties. I will present new bounds using the LSS on two compelling dark matter scenarios that are otherwise...
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Spyros Sypsas (Chulalongkorn University)Poster
The inflationary origin of primordial black holes (PBHs) relies on a large enhancement of the power spectrum of the curvature fluctuation ζ at wavelengths much shorter than those of the CMB anisotropies. Quantum gravity inspired models are characterized by moduli spaces with highly curved geometries and a large number of scalar fields that could vigorously interact with ζ (as in the...
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Eduardo Valadão
Since the late 1980s, when the first gravitational arcs were observed, the strong effect of gravitational lensing has been a key observable in both Cosmology and Extragalactic Astrophysics. This phenomenon predicted by General Relativity, whose effect is the distortion and magnification of the image of a distant cosmic object (source) due to the deflection of the light’s trajectory caused by...
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Rahima MokeddemPlenary/Parallel talk
In this work we extend the remapping method proposed by Mead and Peacock (MNRAS 440, 1233–1247 (2014)). This method allow us to remmap N-body simulations catalogues from one cosmology into another different cosmology directly without necessity of running an N-body simulations for each cosmology. On the other hand, it is well known that 21 cm mocks are constructed from, for example, halo or...
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Pedro Riba MelloPoster
In this talk I'll explore how we can use Shannon entropy and the Surprise to
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quantify discordances between datasets. The Surprise is a tool based on the
Kullback-Leibler divergence and offers a way to quantify discordance between
datasets in multiple dimensions in parameter space. I’ll analyze Supernovae, time
delay gravitational lensing, BAO and CMB data for LambdaCDM model... -
Rodrigo Voivodic
In this talk, I will present the hybrid lagrangian bias expansion and how we can use it to make predictions for the auto and cross bispectra up to non-linear scales. I will show that the third-order bias expansion is enough to describe all triangular configurations of the bispectrum up to scales $\sim 0.6$ Mpc$/h$. We used N-body simulations and a subhalo abundance matching model to test the...
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Daniel LópezPlenary/Parallel talk
The concentrations of dark matter haloes provide crucial information about their internal structure and how it depends on mass and redshift -- the so-called $c(M,z)$ relation. I will present an extensive study of the cosmology-dependence of halo concentrations based on a suite of 72 dark matter-only simulations in which the following cosmological parameters are varied: $\sigma_{8}$,...
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Jullianna Denes Couto (Johns Hopkins University)Poster
The Cosmology Large Angular Scale Surveyor (CLASS) is a set of four ground-based telescopes designed to measure and characterize the polarization signal of the cosmic microwave background (CMB) on the largest angular scales in order to probe the epochs of inflation and reionization. Located in a high-altitude site in the Atacama Desert, CLASS covers 70% of the sky in frequency bands centered...
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Rajesh Kumar DubeyPlenary/Parallel talk
The Hubble's Constant (H0)is one of the most fundamental and essential cosmological parameters which gives the expansion of Local Universe. Hubble’s Constant is measured by different methods and one of them is by using electromagnetic sources called distance ladder. With the detections of gravitational waves and using Gravitational Wave (GW) analysis this value can be measured; making GW...
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AMANDA FARIAS SANTOS (IFUSP), Prof. FILIPE BATONI ABDALLA (IFUSP), GABRIEL HOERNING (IFUSP), Dr KARIN SILVIA FRANZONI FORNAZIER (IFUSP), Prof. RENATA Z. FUNCHAL (IFUSP)Poster
The observation of neutrino flavor oscillations by various experiments involving both natural (solar and atmospheric) and man-made (accelerators and reactors) neutrino sources firmly indicates that neutrinos are massive particles.
In fact, all these experiments can be well understood if we assume the so-called {\it Standard Paradigm} that is, that the three known neutrino interaction...
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Ms Matheus Maia de Araújo Paixão (Brazilian Center for Research in Physics (CBPF))Poster
The particle concept in curved space-time is, in general, observer de-
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pendent, as is well-known from the Unruh effect. This, in particular, is
really important to understand the particle emission from black holes. In
this work, we study the Unruh effect under the perspective of De Broglie-
Bohm interpretation of quantum mechanics, where from the wave func-
tional we obtain the associated...
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