Invited Speakers

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TALK: Lattice gravity: overview and recent progress

ABSTRACT: The talk will describe how it in principle is possible to obtain a continuum, diffeomorphism invariant theory, starting from a lattice theory. It will describe how the Wilsonian view on quantum field theories also makes sense for lattice theories which are intended to be regularized versions of diffeomorphism invariant theories. Finally, this philosophy will be applied to lattice gravity model denoted Causal Dynamical Triangulations (CDT). The CDT results obtained so far will be summarized and the relation to both the renormalization group approach, i.e. to the asymptotic safety scenario, and to Horava-Lifshitz gravity will be outlined.

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TALK: Stellar Turbulence, and why we should care

ABSTRACT: As a preparation for the generation of a new set of core collapse progenitor models, a new investigation of the physics of such stars has begun. Supercomputers allow the simulation of three dimensional highly turbulent flow. Treating these numerical "experiments" as valid representations of the behavior of high energy density (HED) plasma, a view supported by laboratory experiments with inertial confinement fusion (ICF) devices, we are beginning to develop a theory of this behavior appropriate to stellar interiors. Unlike conventional astrophysical convection theory, the Richardson-Kolmogorov turbulent cascade and the Lorenz strange attractor make an appearance, as well as a rich set of boundary-region physics. The process of developing physical insight from numerical simulations will be illustrated, and implications for stellar evolution, from the Sun to gamma-ray bursts and supernovae, will be discussed.

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ABSTRACT: The Wilkinson Microwave Anisotropy Probe (WMAP) produced the first full sky maps of cosmic microwave background (CMB) temperature and polarization fluctuations extending from full sky to sub-horizon scales. The measurements significantly constrain the physics of the very early universe and directly support the inflation prediction that primordial fluctuations were primarily adiabatic and nearly scale-invariant. The measurements also constitute core support for the standard model of cosmology, with accurate and precise cosmological parameters. WMAP data have reduced the cosmological parameter uncertainty volume by a factor of more than 30,000 compared with pre-WMAP CMB results. The standard model specifies the age of the universe and the curvature of the universe to high accuracy. It also specifies the composition of the universe, including the overall matter density, the baryon density, and the cold dark matter density. When combined with other astronomical measurements, the WMAP measurements constrain the properties of the dark energy and the mass of the neutrino. Future CMB observations (from Planck, balloon-borne, and ground-based experiments) and a host of other cosmological observations should be able to further test, constrain, and extend the standard cosmological model.

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TALK: Perturbative Quantum Gravity as a Double Copy of Gauge Theory and Implication for UV Properties

ABSTRACT: The talk will show that in a precise sense gravity scattering amplitudes are double copies of corresponding gauge theory ones used, for example, to describe the strong subnuclear interactions. Underlying this is a correspondence between the color charges of gauge theory and kinematic numerators in gauge and gravity theories. An application of these ideas will be given, demonstrating that within perturbation theory standard supergravity theories are much tamer in the ultraviolet (and perhaps even finite) than had been believed possible.

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TALK: Cosmology with the thermal and kinetic Sunyaev-Zel'dovich effects

ABSTRACT: The Sunyaev-Zel'dovich (SZ) effects are proving to be powerful probes of cosmology. The thermal SZ effect is caused by the scattering of cosmic microwave background (CMB) photons by the hot intracluster gas of galaxy clusters. It is being used to constrain cosmological parameters including the nature of dark energy through its impact of the evolution in the number density of galaxy clusters in the universe. The kinetic SZ effect is caused by the scattering of the CMB photons by bulk motions of the ionized intergalactic medium. It offers a unique probe of the reionization history of the universe. This talk will review the SZ effects, focusing on new results from the 10 meter South Pole Telescope (SPT). The SPT recently completed a 2500 square degree survey of the CMB at unprecedented sensitivity and resolution. The SPT results include the first discovery of galaxy clusters with 100's now discovered and used to constrain cosmology, the detection of the diffuse SZ background and its constraints on the normalization of the matter power spectrum and the reionization of the universe, and high confidence measurements of the gravitational lensing of the CMB. Lastly, we will give and an overview of the SPTpol polarization-sensitive measurements that began in March 2012.

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Thibault DAMOUR

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Frederik DENEF

TALK: String glasses

ABSTRACT: I will review recent work on various complex systems that naturally appear in the context of string theory, black hole physics and inflationary cosmology. It brings together techniques, ideas and concepts from theories of glasses and theories of quantum gravity, including holographic dualities.

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Carlos FRENK

TALK: Everything from nothing: how our universe was made

ABSTRACT: Cosmology confronts some of the most fundamental questions in the whole of science. How and when did our universe begin? What is it made of? How did galaxies and other structures form? There has been enormous progress in the past few decades towards answering these questions. For example, recent observations have established that our universe contains an unexpected mix of components: ordinary atoms, exotic dark matter and a new form of energy called dark energy. Gigantic surveys of galaxies reveal how the universe is structured. Large supercomputer simulations recreate the evolution of the universe and provide the means to relate processes occuring near the beginning with observations of the universe today. A coherent picture of cosmic evolution, going back to a tiny fraction of a second after the Big Bang, is beginning to emerge. However, fundamental issues, like the nature of the dark energy, remain unresolved.

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TALK: Supernova cosmology: past and future

ABSTRACT: During the last two decades, Type Ia supernovae became the main tool to study the expansion history of the Universe and provided the first solid evidence for the accelerated expansion rate in the late 1990's. Since then, the focus for observational cosmology shifted towards trying to establish if the "dark energy" driving the accelerated expansion is constant in time and space, i.e., consistent with Einstein's cosmological constant, Lambda. The current observational constraints on deviations from Lambda will be presented, as well as ongoing efforts aiming at reducing key systematic uncertainties, limiting the precision of Type Ia supernovae as distance indicators.

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TALK: Gravity with Anisotropic Scaling and the Multicritical Universe

ABSTRACT: I provide a review of the recent progress in quantum gravity with Lifshitz-like anisotropic scaling, and its applications in areas ranging from particle phenomenology beyond the standard model, to holographic renormalization in non-relativistic versions of AdS/CFT correspondence.

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TALK: The Accelerating Universe: a Nobel surprise

ABSTRACT: Observations of thermonuclear supernovae halfway across the visible universe provide clear evidence for cosmic acceleration. Now the task is to use those observations to constrain the properties of dark energy. Systematic errors, not sample size, now poses the limit. One of the most promising paths to better knowledge of dark energy is to use supernovae, but to make the observations in the rest frame infrared. I will describe what is known about the infrared emission from supernovae and outline how to make progress on learning the properties of dark energy.

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TALK: Recent developments in mathematical GR

ABSTRACT: The last four years have seen spectacular progress in mathematical GR. Here are some of the most important developments:

  1. Resolution of the Bounded $L^2$ curvature conjecture
  2. Formation of trapped surfaces in vacuum
  3. Rigidity of the Kerr solution among smooth stationary vacuum solutions
  4. Boundedness and decay of general solutions to the linear wave equation in the exterior region of Kerr

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Michael KRAMER

TALK: Precision tests of theories of gravity using pulsars

ABSTRACT: In the quest of understanding gravity, binary pulsars provide indispensable laboratories for precision tests of gravity. Effects that can be studied in great detail include the emission of gravitational waves, Shapiro delay, orbital precession and more. But also fundamental differences between general relativity and alternative theories of gravity can be probed, such as possible violations of the strong equivalence principle, preferred frame effects or the existence of gravitational dipole radiation or scalar fields. Also the effects of spin precession in strongly self-gravitating bodies can be studied by observing effects of geodetic precession. This review talk will present the latest results with some new exciting results.

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TALK: The greatest scientific achievements of the Hubble space telescope

ABSTRACT: I will briefly present the most important scientific topics to which the Hubble Space Telescope has made crucial contributions. The subjects will range from the solar system, and extrasolar planets, to the formation and evolution of galaxies, the age of the universe, and dark energy. Along the way I will show some of the most stunning images taken by Hubble, and discuss the impact that the telescope has had on cosmology and astrophysics.

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TALK: Connecting the Dark and Light Side of Galaxy Formation

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Luciano MAIANI

TALK: LHC High-lights

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TALK: Planck and fundamental physics

ABSTRACT: The Planck Low Frequency Instrument will be described together with its performances and the up to date status of the Planck satellite. An outline of early astrophysical results from the Planck Collaboration will be provided. The expected Planck results in the Fundamental Physics will also be presented. Furthermore an outline of the Planck product and papers release will be given.

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TALK: Recent searches of the Standard Model Higgs within CMS

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TALK: Hidden symmetries: from BKL to Kac-Moody

ABSTRACT: The seminal work of Belinski, Khalatnikov and Lifshitz on spacelike singularities in cosmological solutions of Einstein's equations has not only generated a new paradigm in General Relativity, but may also provide important hints as to the underlying symmetries of a future unified theory of the fundamental interactions and of quantum gravity. In this talk I will briefly retrace the steps from their early work to more recent developments.

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TALK: Search for the Standard Model Higgs with the ATLAS detector

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TALK: Electromagnetic Signals from Neutron Star Mergers

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Jean-Loup PUGET

TALK: High Energy Planck Mission

ABSTRACT: The achieved Planck High Frequency Instrument survey performances will be described. The very high sensitivity provided by the 100mK bolometers will allow to test early universe cosmology models (especially inflationary models).Other expected results directly related to fundamental physics questions will also be described. Astrophysical cosmology results from the early Planck Collaboration papers will also be presented.

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Harvey REALL

TALK: Black holes in higher dimensions

ABSTRACT: I shall review what is known about black holes in higher dimensions. I shall discuss the known explicit solutions, results concerning the classification of stationary black holes, and instabilities of rotating black holes in higher dimensions.

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TALK: Ground-based Gravitational-wave Astronomy Using Interferometers: Past and Future

ABSTRACT: The first generation of large-scale gravitational-wave interferometers � LIGO (USA), Virgo and GEO600 (Europe) -- has completed their first searches for gravitational waves and gone offline. Alas, gravitational waves remain elusive, however there is good reason for optimism that detections will come with the next generation of instruments currently being built -- Advanced LIGO (USA), Advanced Virgo and GEO600 (Europe), and KAGRA (Japan). In this talk, I'll review the latest scientific results from searches for gravitational waves -- from compact binary mergers and GRBs, from galactic pulsars, and from the primordial universe. I�ll also present the status of the coming global network of gravitational-wave network with an emphasis on Advanced LIGO.

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TALK: QEG: Towards an Asymptotically Safe Quantum Theory of Gravity

ABSTRACT: This talk will give a brief introduction to the basic ideas and methods of the Asymptotic Safety program which is aiming at the construction of a non-perturbatively renormalized and background independent quantum field theory of gravity. Recent results on the viability of this program, as well as on the physical mechanism underlying Asymptotic Safety will also be discussed.

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TALK: Using numerical relativity to explore fundamental physics and astrophysics

ABSTRACT: Recent years have seen a major progress in numerical relativity and the solution of the simplest and yet among the most challenging problems in classical general relativity: that of the evolution of two objects interacting only gravitationally. I will review the results obtained so far when modelling binaries of black holes or of neutron stars and also discuss the impact these studies have in detection of gravitational-waves, in astrophysics, and in our understanding of general relativity.

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TALK: Strong, Weak, Electromagnetic and Gravitational Interactions in Neutron Stars

ABSTRACT: The observations of the most energetic astrophysical objects, the Gamma-Ray Bursts (GRBs), unveil crucial information on the process of gravitational collapse to a black hole (BH). They are powerful progenitor machines able to emit energy up to a solar mass of electromagnetic radiation in a few seconds. Short GRBs are believed to be the outcome of the gravitational collapse to a BH of overcritical Neutron Star (NS) due to NSs binary mergers. The traditional Tolman-Oppenheimer-Volkoff (TOV) equations of NSs assume local charge neutrality and electromagnetic structure is not accounted for. We show that such an assumption is inconsistent when all known interactions in NS equilibrium equations are present, including electromagnetism. We present the new Einstein-Maxwell-Thomas-Fermi (EMTF) set of equations, which must be solved under the constraint of global, but not local, charge neutrality. The numerical solution of these equations shows that the crust mass and thickness are smaller compared to the values obntained within a TOV-like approach, leading to a new neutron star mass-radius relation. The existence of neutron stars without the presence of inner crusts is shown. In the transition region between the core and the crust globally neutral NSs possess internal electric fields that reach values much larger than the critical Euler-Schwinger-Heisenberg field. This field is stable due to Pauli Blocking of degenerate electrons. We finally show how the observations of the genuinely short GRB, GRB 090227B, are consistent with the new NS mass-radius relation obtained in this theory.

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TALK: GRBs and the Supernova-Neutron-Star-Black-Hole Sequence

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TALK: The Cosmic Microwave Background and the Hidden Universe

ABSTRACT: Large-scale CMB observations have played an important role in measuring the physical conditions at z=1100 and in establishing a standard cosmological model. In the coming decade, small-scale CMB observations will help us explore the "hidden universe": the dark matter, the dark energy and the "missing" baryons in the intergalactic medium through observations of the thermal Sunyaev-Zel'dovich effect, the kinematic Sunyaev-Zel'dovich (kSZ) effect and through gravitational lensing of the CMB. I will describe results from the Atacama Cosmology Telescope including the first detections of the kSZ effect and the first measurement of CMB lensing. I will also look forward to upcoming data from ACTPOL, which should begin observing in summer 2012, and from a large survey that will be conducted with HyperSuprime Camera, a 1.5 x 1.5 degree camera on the Subaru telescope that will map the same region of the sky.

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TALK: Unavoidable CMB spectral features and Black Body Photosphere of our Universe

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TALK: Spacetime singularities: Recent developments

ABSTRACT: This talk reviews and gives a historical background to recent developments concerning spacelike singularities in general relativity. The talk consists of two parts. The first part presents mathematically rigorous results about generic singularities in spatially homogeneous cosmology, most notably Bianchi types VIII and IX. The second part describes recent analytical and numerical results concerning generic behavior and so-called recurring spike formation toward a generic spacelike singularity in inhomogeneous cosmology. Both parts of the talk involve connections between asymptotic behavior, hierarchical structures, and solution generating techniques, which provide new hints for the existence of hidden asymptotic symmetries.

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TALK: Open Questions in GRB Physics

ABSTRACT: I will review some open questions in GRB physics, including origins of prompt emission and afterglow, the composition of the ejecta, energy dissipation and emission mechanisms of the jet, central engine, progenitor, and classification.