Gravitational waves: a new messenger to explore the universe

Liste des contributions

50. Presentation of the Centre Emile Borel of IHP

01/03/2021 09:30

17. Lecture: Methods of post-Newtonian expansion

Luc Blanchet

01/03/2021 10:00

45. Lecture: Relativistic hydrodynamics

Luciano Rezzolla

01/03/2021 16:00

18. Lecture: Gravitational theories

Shinji Mukohyama

02/03/2021 10:00

19. Lecture: Gravitational waveforms

Alessandra Buonanno

02/03/2021 16:00

20. Lecture: Gravitational theories

Shinji Mukohyama

03/03/2021 10:00

21. Lecture: Gravitational-wave detectors

David Shoemaker

03/03/2021 16:00

44. Lecture: Gravitational waveforms

Alessandra Buonanno

04/03/2021 10:00

22. Lecture: Gravitational-wave detectors

David Shoemaker

04/03/2021 16:00

23. Interdisciplinary seminar: Introduction to astrophysical observations

Susanna Vergani

05/03/2021 10:00

46. Gather town interaction

05/03/2021 11:00

47. Interdisciplinary seminar: Machine learning for detectors and data analysis

Gabriele Vajente

05/03/2021 16:00

24. Gather town interaction

05/03/2021 17:00

36. Lecture: (Massive) black hole binaries

Monica Colpi

08/03/2021 10:00

43. Lecture: (Massive) black hole binaries

Monica Colpi

08/03/2021 16:00

37. Lecture: Gravitational waves and cosmology

Danièle Steer

09/03/2021 10:00

39. Lecture: Gravitational-wave data analysis

Neil Cornish

09/03/2021 16:00

38. Lecture: Multi-messenger astrophysics

Giancarlo Ghirlanda

10/03/2021 10:00

48. Lecture: Gravitational-wave data analysis

Neil Cornish

10/03/2021 16:00

41. Lecture: Multi-messenger astrophysics

Giancarlo Ghirlanda

11/03/2021 10:00

42. Lecture: Gravitational waves and cosmology

Danièle Steer

11/03/2021 16:00

40. Interdisciplinary seminar: Stochastic gravitational wave background -- the need of a multifaceted

Germano Nardini

12/03/2021 10:00

49. Gather town interaction

12/03/2021 11:00

56. Constraining the Hubble constant and modified GW propagation with LIGO-Virgo dark sirens

Poster

The recent detections and data releases from LIGO-Virgo enable the first applications of statistical methods for constraining the Hubble parameter with Gravitational Waves (GWs).
Moreover, they open up the possibility of new tests of General Relativity, since modified gravity models predict a non-standard GW luminosity distance, which is measured directly from the GW signal. By adding...

72. Cosmology with low-redshift observations: No signal for new physics

Poster

We analyse various low-redshift cosmological data from Type-Ia Supernova, Baryon Acoustic Oscillations, Time-Delay measurements using Strong-Lensing, $H(z)$ measurements using Cosmic Chronometers and growth measurements from large scale structure observations for $\Lambda$CDM and some different dark energy models. By calculating the Bayesian Evidence for different dark energy models, we find...

68. Eccentric binary black hole surrogate models for the gravitational waveform andremnant properties: comparable mass, nonspinning case

Poster

We develop new strategies to build numerical relativity surrogate models for
eccentric binary black hole systems, which are expected to play an increasingly
important role in current and future gravitational-wave detectors. We
introduce a new surrogate waveform model, NRSur2dq1Ecc, using 47
nonspinning, equal-mass waveforms with eccentricities up to $0.2$ when measured
at a reference...

73. GPE: GPU-accelerated parameter estimation for gravitational waves with x360 acceleration

Poster

We present GPE, a GPU-accelerated parameter estimation package for gravitational waves from compact binary coalescence sources. This stand-alone program is adapted from the nested sampling flavor of LALInference. Two main parallelization methods are implemented: (1) the frequency-domain waveform and likelihood calculations, (2) and the prior sampling portion in the nested sampling algorithm....

52. Gravitational waves from tidal disruption events

If a star gets too close from a black hole (BH), the former can be disrupted by the tidal forces of the latter, resulting in a luminous event known as a tidal disruption event (TDE). Furthermore, the extreme nature of the system also results in the emission of gravitational waves, which carry additional informations about the properties of the BH and the star. As such, TDEs potentially allow...

65. Gravitational-wave polarimetry with quaternions and application to precessing binaries

Poster

In this poster we introduce a new model free polarimetric analysis method based on quaternion Fourier transform and we also present a method to reconstruct both gravitational-wave polarizations from the full network data. Interestingly, this formalism allows to formulate generic priors on the polarization that can guide the problem inversion. As an illustration we perform the polarimetric...

64. Higher-curvature variations of R^2-inflation

Poster

We sketch the inflationary predictions from a class of higher-curvature corrections to Starobinsky inflation and propose constraints on these theories, inspired by holography.

53. Impact of dark matter on compact stars and their merger dynamics

Poster

We study an impact of asymmetric dark matter on properties of the neutron stars and their ability to reach the two solar masses limit, which allows us to present a new range of masses of dark matter particles and their fractions inside the star. Our analysis is based on the observational fact of the existence of two pulsars reaching this limit and on the theoretically predicted reduction of...

6. Interdisciplinary seminar

31. Interdisciplinary seminar

66. It takes two (spins) to tango: Interpreting gravitational-wave data with a generalized effective precession parameter

Poster

Current gravitational-wave data analysis of merging binary black holes accounts for two precessing spins, allowing inference of the six spin degrees of freedom. Nonetheless, it is convenient to use effective parameters to interpret detections; the effective aligned spin $\chi_{\rm{eff}}$ and the effective precessing spin $\chi_{\rm{p}}$ measure components parallel and perpendicular to the...

1. Lecture: (Massive) black hole binaries

Monica Colpi

8. Lecture: (Massive) black hole binaries

Monica Colpi

7. Lecture: Gravitational waves and cosmology

Danièle Steer

10. Lecture: Gravitational waves and cosmology

Danièle Steer

25. Lecture: Gravitational-wave data analysis

Prof. Neil Cornish (Montana State Univ.)

29. Lecture: Gravitational-wave data analysis

Prof. Neil Cornish (Montana State Univ.)

30. Lecture: Gravitational-wave data analysis

Prof. Neil Cornish (Montana State Univ.)

26. Lecture: Gravitational-wave detectors

David Shoemaker (MIT)

27. Lecture: Gravitational-wave detectors

David Shoemaker (MIT)

28. Lecture: Gravitational-wave detectors

David Shoemaker (MIT)

4. Lecture: Multi-messenger astrophysics

Giancarlo Ghirlanda

9. Lecture: Multi-messenger astrophysics

Giancarlo Ghirlanda

74. Mapping the inhomogeneous Universe with Standard Sirens: Degeneracy between inhomogeneity and modified gravity theories

Poster

The detection of gravitational waves (GWs) and an accompanying electromagnetic (E/M) counterpart have been suggested as a future probe for cosmology and theories of gravity. In this paper, we present calculations of the luminosity distance of sources taking into account inhomogeneities in the matter distribution that are predicted in numerical simulations of structure formation. In addition,...

54. Metric reconstruction with gravitational waves and shadows

Poster

In this poster I present two recent works [1,2] that aim to enhance our understanding of reconstructing black hole space-times from different type of observations. While gravitational wave detectors like LIGO/Virgo allow to perform black hole spectroscopy of stellar mass black holes, images such as those produced by the Event Horizon Telescope provide information of the shadow from super...

14. Mini-conference

35. Mini-conference

63. Multi-messenger probes of extreme gravity around black holes

Poster

For nearly a century, Einstein’s theory of gravity has been the standard theory for describing gravitational phenomena in our universe. Along with its successes, there are some questions for which it does not provide a satisfactory answer. This has led to proposals that modify or supersede Einstein’s theory, and testing these theories against data, especially in the strong-field regime, has...

70. Predictions for LISA and PTA based on SHARK galaxy simulations

Poster

Massive black holes, with masses ranging from tens of thousands to billions of solar masses are undeniably intertwined with their galactic hosts. There are a number of empirical relations linking central black holes with their galactic environment on both large and small scales, including bulge luminosities, stellar velocity dispersion or halo mass just to mention a few. Unfortunately, we are...

58. Probing Supermassive blackholes with LISA

Poster

We study hydrodynamical simulations of galaxy formation, based on the GADGET-3 code, and investigate supermassive black hole binaries coalescence at $5.5

55. Revisiting a family of wormholes: geometry, matter, scalar quasi-normal modes and echoes

Poster

In our work ‘Revisiting a family of wormholes: geometry, matter, scalar quasi-normal modes and echoes (P.D.Roy, S. Aneesh, S. Kar, Eur. Phys. J. C (2020) 80: 850)’ we study the behavior of a family of ultrastatic, Lorentzian wormholes having two parameters, namely ‘n’ that controls the geometry of each member wormhole and throat radius ‘b_0’, under scalar perturbations. For n=2 ...

2. Seminar

3. Seminar

5. Seminar

11. Seminar

12. Seminar

13. Seminar

32. Seminar

33. Seminar

34. Seminar

62. Simulation-efficient marginal posterior estimation with swyft

Poster

We present algorithms (a) for nested neural likelihood-to-evidence ratio estimation, and (b) for simulation reuse via an inhomogeneous Poisson point process cache of parameters and corresponding simulations. Together, these algorithms enable automatic and extremely simulator efficient estimation of marginal and joint posteriors. The algorithms are applicable to a wide range of physics and...

59. Stacked Search for Gravitatinal Waves

Poster

In the last few years, progressively more frequent and precise direct detections of gravitational waves have facilitated sensitive tests of general relativity. Among the most intriguing possibilities is the existence of horizonless objects more compact than the photon ring. If such objects exist, it is inevitable that in addition to a standard ringdown, there will be late-time echoes of...

61. The cosmic merger rate density of compact binaries

Poster

With the recent publication of the second gravitational wave transient catalog by the LIGO-Virgo collaboration (LVC), the number of binary compact object mergers has risen dramatically, from a dozen to ~ 50 events. From these detections, the LVC inferred the merger rate density both in the local Universe and as a function of redshift. It is then of foremost importance to compare the merger...

60. The impact of common envelope development criteria on the formation of LIGO/Virgo sources

Poster

The treatment and criteria for development of unstable Roche lobe overflow (RLOF) that leads to the common envelope (CE) phase have hindered the evolutionary predictions for decades. In particular, the formation of black hole–black hole (BH-BH), black hole–neutron star (BH-NS), and neutron star–neutron star (NS-NS) merging binaries depends sensitively on the CE phase in classical isolated...

71. The Probability Distribution of Astrophysical Gravitational-Wave Background Fluctuations

Poster

The coalescence of compact binary stars is expected to produce a stochastic background of gravitational waves (GW) observable with future GW detectors. Such backgrounds are usually characterized by their power spectrum as a function of frequency. Here, we present a method to calculate the full 1-point distribution of strain fluctuations. We focus on time series data, but our approach...

69. Workshop_MPETHA_Charlie

Poster

With planned future gravitational wave observatories such as LISA and Einstein Telescope, coupled with powerful telescopes such as Euclid, it is vital we explore how these two windows into the content and dynamics of the Universe can complement one another. The weak lensing of gravitational waves found using luminosity distances obtained from compact binary coalescences, and redshifts from...

67. “How does antimatter fall?”: focus on GBAR experiment (CERN)

Poster

One of the main questions of fundamental physics is the action of gravity on antimatter. We present here the simulation of the last part of the experiment GBAR at CERN, i.e. the measurement of the free fall acceleration 𝑔̅ of antihydrogen atoms in the gravitational field of Earth. A precision of the measurement beyond the % level is confirmed by taking into account the experimental design.