Conférences - Astronomie, astrophysique et cosmologie - États-Unis

Institute for Pure and Applied Mathematics (IPAM), UCLA

The aim of this program is to connect efforts of the mathematical and physical sciences communities to address the latest advances and new challenges on the understanding of multi-messenger astronomy. The IPAM program will comprise four workshops, each addressing a different topic: the generation of catalogs of waveform templates; the discussion of the mathematical modeling of the equations governing strong relativistic systems; parameter estimation of astrophysical sources of gravitational waves; and the state of the art of big data and deep learning techniques for GW data analysis.

Physique des hautes énergies, des particules et des champs,    Calcul scientifique

IPAM - Institute for Pure & Applied Mathematics, an NSF Math Institute at UCLA

The program opens with several days of tutorials that will provide an introduction to major themes of the entire program and the four workshops. The goal is to build a foundation for the participants of this program who have diverse scientific backgrounds. For those participating in the long program, please plan to attend Opening Day on September 13, 2021 as well. Others may participate in Opening Day by invitation from the organizing committee.

Part of the Long Program Mathematical and Computational Challenges in the Era of Gravitational Wave Astronomy

Cours et évènements pour étudiants en mathématiques,    Cours et événements pour étudiants en physique

IPAM - Institute for Pure & Applied Mathematics, an NSF Math Institute at UCLA

Computational relativistic astrophysics and numerical relativity face a number of challenges following the first detection of binary black holes and binary neutron stars: high Lorentz factors, strong and dynamical gravitational fields, uncertain equations of state, magnetic fields, radiative and dissipative effects, large dynamical ranges, solutions of constrained hyperbolic systems. The likely gravitational signals produced after the collapse of massive stellar cores offer unique probes of the dynamics of newly-born compact stellar remnants. Predicting source dynamics of future detections of gravitational wave signals is important to understand the physics of these events in the current and next-generation earth-based gravitational-wave detectors and essential to achieve design sensitivity in future space-based detectors. The goal of this workshop is to bring together mathematical modelers in general relativity, astrophysicists, and experts in numerical relativity to discuss open issues to improve current approaches to build increasingly more accurate gravitational wave templates that allow to identify future detections.

Part of the Long Program Mathematical and Computational Challenges in the Era of Gravitational Wave Astronomy

Cours et évènements pour étudiants en mathématiques,    Cours et événements pour étudiants en physique

IPAM - Institute for Pure & Applied Mathematics, an NSF Math Institute at UCLA

Ever since general relativity’s birth in 1915, mathematics has had a profound impact on the way the theory has been understood: Examples over the years include Hilbert’s variational formulation, Noether’s early theorems on conservation laws, Choquet-Bruhat’s foundational well-posedness theorem and the hyperbolicity of the equations, Bondi’s concept of null infinity and gravitational waves, the incompleteness theorems of Penrose and the black hole concept, the positive energy theorem of Schoen and Yau, and the nonlinear stability of Minkowski space proven by Christodoulou and Klainerman. In more recent years, the power of numerics has added additional insights to our mathematical picture, particularly after Pretorius’s 2004 breakthrough allowing for the numerical simulation of binary black hole systems. Today, research on mathematical and numerical aspects of general relativity constitute two vibrant fields which have become very influential in the wider mathematics and physics communities. The two fields have many points of contact: Some common goals shared by both rigorous mathematical analysis and numerics include understanding the formation of black holes in gravitational collapse, their non-linear stability, and their interaction with other black holes in binary systems or other scattering processes. In their practical application to astrophysics, the two fields often play complementary roles: Numerics generates the templates which play an important part in interpreting gravitational wave detections by LIGO and VIRGO, while rigorous mathematical analysis has introduced subtle new concepts, like Christodoulou memory, which may play an important role in the next generation of detectors. Another common goal of both rigorous mathematics and of numerics, of interest to theoretical physics, is to understand generic spacetime singularities, so as to resolve in particular the celebrated weak and strong cosmic censorship conjectures of Penrose. As singularities probe the limits of the theory, a resolution of these conjectures may shed light on various attempts to transcend general relativity. Other recent problems which have brought together mathematics and numerics include work on asymptotically anti-de Sitter spacetimes, and well-posedness for alternative theories of gravity, both of interest in high energy physics. There is also recent activity on inverse problems. This workshop will gather mathematicians, theoretical physicists and numerical analysis developers to discuss these and other issues.

Part of the Long Program Mathematical and Computational Challenges in the Era of Gravitational Wave Astronomy

Cours et évènements pour étudiants en mathématiques,    Cours et événements pour étudiants en physique

UC Santa Barbara, Kavli Institute for Theoretical Physics (KITP)

Many of the largest uncertainties in the physics of stars are related to transport in their interiors, including the transport of heat, chemical elements, and angular momentum. Our current understanding of these processes has been challenged and refined by recent advances in observational data, including TESS and spectroscopic studies, by new work on 1D models, and by the ability to generate more sophisticated 3D simulations. This conference will bring together members of the community working on transport processes from a variety of angles, including observations, theoretical calculations, and stellar models, with an emphasis on how these techniques can be combined to improve our understanding of stellar physics.

Physique des plasmas, fusion nucléaire,    Physique numérique

IPAM - Institute for Pure & Applied Mathematics, an NSF Math Institute at UCLA

Gravitational-wave (GW) observations offer a unique opportunity to study astrophysical and cosmological sources that are difficult to access through electromagnetic observations. Inferring the sources’ properties from their GW signal is one of the key objectives of GW data analysis. The planned improvements in the sensitivity of the ground-based detectors and future space-based observatories, however, bring unique computational and mathematical challenges to the inference problem including long-duration signals, high signal-to-noise ratios, increased parameter dimensionality and overlapping signals. These challenges must be overcome to fully exploit the scientific potential of GW observations. The goal of this workshop is to connect statisticians, computer scientists and GW astrophysicists to discuss the current state-of-the-art approaches to parameter estimation in GW astrophysics, and to identify the open issues to enable fast and reliable inference for different GW sources, including modelled and un-modelled signals, for the current and planned GW observatories.

Part of the Long Program Mathematical and Computational Challenges in the Era of Gravitational Wave Astronomy

Cours et évènements pour étudiants en mathématiques,    Cours et événements pour étudiants en physique

IPAM - Institute for Pure & Applied Mathematics, an NSF Math Institute at UCLA

Detection of gravitational waves requires the operation of very sophisticated detectors producing large amounts of data. The sensitivity of the gravitational-wave detectors to astrophysical signals is limited by the noise associated with the instruments themselves and their environment. Invaluable astrophysical information is buried in data sets that may be too large or complex to be analyzed with traditional data-processing techniques. To make the analysis of gravitational-wave detector data more efficient it becomes increasingly more important to characterize and mitigate the detector noise sources, as well as find more powerful ways to extract information from the detector data. Methods for the analysis of gravitational-wave detector data range from standard signal processing algorithms to novel machine learning algorithms. This workshop will focus on the development of these techniques for a more efficient handling of gravitational-wave data sets, reduction of detector noise, identification of astrophysical signals and increase in detection confidence. It will bring together astrophysicists, mathematicians and statisticians working on the state-of-the-art data analysis.

Part of the Long Program Mathematical and Computational Challenges in the Era of Gravitational Wave Astronomy

Cours et évènements pour étudiants en mathématiques,    Cours et événements pour étudiants en physique

UC Santa Barbara, Kavli Institute for Theoretical Physics (KITP)

Binary systems are ubiquitous in nature, from stars to the supermassive black holes expected to reside in galactic nuclei. In many circumstances, the binary system is enveloped by circumbinary gas. How does circumbinary gas evolve and influence the embedded binary? What observational signatures of this gas are most informative? What novel numerical techniques must we deploy to better model these systems? This conference will bring together two distinct communities: those working on massive black hole binaries with those working on stellar binaries. Because recent years have seen remarkable progress in observations of stellar binaries, and numerical modeling of both stars and black holes, now is the ideal time to bring together these two groups. The conference will highlight the remarkable similarities of problems at such varied astrophysical scales, and shed light on the crucial next steps for pushing the boundaries of our knowledge.

UC Santa Barbara, Kavli Institute for Theoretical Physics (KITP)

The goal of this conference is to survey the interdisciplinary avenues in modern neutrino physics, with a threefold overarching set of aims: (1) to maximize the new physics potential of present and upcoming experimental data, (2) to understand new directions in the quest for high-precision neutrino cross sections, including synergy with lattice QCD; and, (3) to ensure that the impact of neutrinos on astrophysical and cosmological processes is comprehensively addressed. Particular attention will be given to exploring connections between neutrinos and gravitational waves, cosmological data, sources for IceCube’s astrophysical neutrino events, implications of the latest sterile searches for cosmology and astrophysics, and an assessment of the role of the neutrino detectors as astrophysical observatories.

UC Santa Barbara, Kavli Institute for Theoretical Physics (KITP)

The detection of gravitational waves by Advanced LIGO/Virgo has opened a new frontier in physics, with impact on areas ranging from field theory through stellar evolution and cosmology. It has also seeded new connections between theoretical communities, especially between field theorists and classical relativists. An even brighter future lies ahead, with more sensitive ground-based detectors and, eventually, a space-based observatory. Current and future experiments demand precision modelling of gravitational-wave signals in order to interpret the strongest gravitational-wave events and to enable sensitive searches for new physics which may be embedded in these signals. The conference will bring together experts from three communities: classical relativity, effective field theory, and scattering amplitudes. Building on the current state of the art, we will discuss the needs of the next generation of gravitational-wave experiments; identify which challenges theory must overcome; highlight recent advances in gravitational wave modelling for more detailed study; and uncover the most promising emerging tools and techniques from classical and quantum field theory for further development.

One of the central features of the AAS Summer and Winter Meetings is their plenary talks spanning the full breadth of astrophysics. Some plenaries are given by prize winners from the AAS and other organizations, while other speakers are selected by the AAS Vice Presidents. Most plenary talks present science content, but talks on the state of the profession, demographics, and societal issues of relevance to the astronomical community are also regularly scheduled.

The Triennial Earth-Sun Summit is a joint meeting of the AAS Solar Physics Division and the Space Physics and Aeronomy Section of the American Geophysical Union.

TESS welcomes participation by the entire Heliophysics community, including all four traditional sub-disciplines devoted to studies of the Sun, Heliosphere, Magnetosphere, and Ionosphere-Thermosphere-Mesosphere. TESS not only promotes greater interaction and unity within Heliophysics, but also connections to astrophysics and planetary physics.

One of the central features of the AAS Summer and Winter Meetings is their plenary talks spanning the full breadth of astrophysics. Some plenaries are given by prize winners from the AAS and other organizations, while other speakers are selected by the AAS Vice Presidents. Most plenary talks present science content, but talks on the state of the profession, demographics, and societal issues of relevance to the astronomical community are also regularly scheduled.

One of the central features of the AAS Summer and Winter Meetings is their plenary talks spanning the full breadth of astrophysics. Some plenaries are given by prize winners from the AAS and other organizations, while other speakers are selected by the AAS Vice Presidents. Most plenary talks present science content, but talks on the state of the profession, demographics, and societal issues of relevance to the astronomical community are also regularly scheduled.