List of participants to the 2nd edition, 5-7 October 2011.

  • G. Batrouni (INLN, Nice, France)
  • E. Bianchi (CPT Marseille, France)
  • C. Bender (Washington University, USA)
  • B. Candelpergher (LJAD, Nice, FRANCE)
  • H. Culetu (Romania)
  • H. M. Fried (Brown, USA)
  • M. Gattobigio (INLN, Nice, France)
  • T. Grandou (INLN, Nice, France)
  • A. Grossmann
  • R. Hofmann (Universitaet Heidelberg, Germany)
  • M. Le Bellac (INLN, Nice, France)
  • P. Martinetti (Università di Roma, Italy)
  • B. Mueller (Duke University, USA)
  • F. Patras (CNRS, Nice, France)
  • B. Raffaelli (INLN, Nice, France)
  • J. Rubin (INLN, Nice, France)
  • P. Tsang (Brown, USA)
  • J. Vitting Andersen (INLN, Nice, France)

Final program and talks of the 2nd edition

Wednesday, 5 October

10:30-11:30 E. Bianchi Loop Quantum Gravity and Spin Foams
11:30-12:30 B. Raffaelli Towards a reggeization of Black Holes Physics? From fascination to observation.
12:30-14:00 LUNCH
14:00-15:00 B. Muller Equilibration and Thermalization of Strongly Coupled Field Theories
15:00-16:00 J. Vitting Andersen Finance applied to Physics - Physics applied to Finance
16:00-16:30 Coffee Break
16:30-17:30 H. M. Fried Construction of a Nucleon-Nucleon Potential from an Analytic, Non-Perturbative, Gauge-invariant QCD
17:30-18:30 B. Muller Physics with Two Time-like Dimensions


Thursday, 6 October

10:30-11:00 M. Le Bellac Why is quantum mechanics so special?
11:00-12:00 P. Martinetti Non-commutative geometry with applications to quantum physics
12:00-14:00 LUNCH
14:00-14:30 A. Grossmann Fat-tailed wavefunctions in elementary quantum mechanics
14:30-15:15 C. Bender Latest results on PT quantum theory
15:15-15:45 Coffee Break
15:45-16:30 C. Bender TBA
16:30-17:30 G. Batrouni TBA

Friday, 7 October

11:15-12:00 R. Hofmann Thermal ground state in deconfining SU(2) Yang-Mills thermodynamics
12:00-14:00 LUNCH
14:00-14:45 R. Hofmann Nonperturbative beta function and effective radiative corrections
14:45-15:45 H. Culetu Anisotropic fluid inside a relativistic star
15:45-16:15 Coffee Break
16:15-17:15 F. Patras Multiplicative renormalization revisited

List of Talks

George Batrouni TBA TBA
Eugenio Bianchi Loop Quantum Gravity and Spin Foams Loop Quantum Gravity is a candidate theory for the quantum degrees of freedom of the gravitational field. Recently, a simple covariant description of its dynamics has been identified (Spin Foams) and contact with classical General Relativity is now available. I will review the present status of this research program, highlighting the developments of the last 3 years, the current open problems, and the possible phenomenological implications for early cosmology.
Carl Bender Latest results on PT quantum theory TBA
Hristu Culetu Anisotropic fluid inside a relativistic star An anisotropic fluid with variable energy density and negative pressure is proposed, both outside and inside stars, on the basis of a recent paper by Grumiller. The gravitational field is constant everywhere in free space (if we neglect the local contributions) and its value is of the order of $g = 10^{~-8} cm/s^{2}$, in accordance with MOND model. With $\rho,~ p \propto 1/r$, the acceleration is also constant inside stars but the value is different from one star to another and depends on their mass $M$ and radius $R$. In spite of the fact that the spacetime is of Rindler type and curved even far from a local mass, the active gravitational energy on the horizon is $-1/4g$, as for the flat Rindler space, excepting the negative sign.
Herbert Fried Construction of a Nucleon-Nucleon Potential from an Analytic, Non-Perturbative, Gauge-invariant QCD As the second application of this new approach to QCD, a gluon "bundle" ( containing an infinite number of gluons, including cubic and quartic gluon interactions) is exchanged between the bound gluons of one nucleon and one point on a closed quark loop; and between another point on that closed quark loop and the bound quarks of the second nucleon. The potential resulting from this process strongly resembles, in form and magnitude, the phenomenological potential long used to describe the deuteron bound state. Here, analytically, is probably the first example of Nuclear Physics from basic QCD.
Alex Grossmann Fat-tailed wavefunctions in elementary quantum mechanics Let us say that a square integrable \psi(x) is fat-tailed if x\psi(x) is not square integrable. A class of examples is given by momentum-shifted Levy distributions. By space shifts and rescalings they produce a counterpart to the well known coherent state representation. This seems promising for the description of time evolution of wave packets.
Ralf Hofmann Thermal ground state in deconfining SU(2) Yang-Mills thermodynamics We demonstrate how an inert, adjoint scalar field emerges upon spatial coarse graining over noninteracting calorons of unit topological charge. The modulus of this field arises due to Euler-Lagrange and BPS consistency which determine its potential uniquely. Perturbative renormalizability and the scalar field's inertness uniquely fix the effective action after coarse-graining, and we solve its equations of motion for a nonperturbative thermal ground-state estimate. The adjoint Higgs mechanism generates a thermodynamically consistent mass for two out of three directions in su(2) provided that a first-order evolution equation for the effective gauge coupling is obeyed. Almost everywhere in temperature the value of the effective coupling turns out to be such that the action of an individual (unresolved) caloron takes the value $\hbar$.
Nonperturbative beta function and effective radiative corrections Appealing to the trace anomaly for the energy-momentum tensor, we compute the nonperturbative beta function for the fundamental coupling from the results of the effective theory for deconfining SU(2) Yang-Mills thermodynamics. Except for nonperturbative screening effects close to the Landau pole the nonperturbative behavior is similar to the perturbative evolution. We also sketch the computation of effective radiative corrections which are organized into a rapidly convergent loop expansion. Some implications for the physics of low-temperature and low-frequency photon propagation are pointed out.
Michel Le Bellac Why is quantum mechanics so special? Bell's inequalities are by now well-known: Bell wrote down a quantity S which is bounded by 3 (S<=3) whatever the classical communication strategy, and which may be larger than 3 in quantum mechanics, however while obeying the Tsirelson bound S<2+\sqrt{2}. The fact that S>3 allows us to claim that quantum mechanics is, in some sense, "non-local". The violation of Bell's inequalities is attributed to entanglement, and it is often claimed that entanglement is the most specific feature of quantum mechanics. However, there are still some questions left unanswered. Superficially, the upper bound on S is not Tsirelson's but S<4. It is possible to write models where 2+\sqrt{2} <= S <= 4 without violating the no-signalling principle, the impossibility of transmitting information at a speed larger than the speed of light. What prevents quantum mechanics of not being more non-local by violating Tsirelson's bound? There is another fundamental theorem by Kochen and Specker which excludes non contextual hidden variables. Is it possible to formulate this theorem in the form of inequalities, anolog to Bell's inequalities, which are violated by quantum mechanics, without using entanglement? Thus, is entanglement the fundamental feature of quantum mechanics? I'll review recent progress made on these two questions.
Pierre Martinetti Non-commutative geometry with applications to quantum physics We shall give an overview of non-commutative geometry, emphasizing various approaches, like Connes spectral triple theory or deformation of Minkowski spacetime. We will illustrate the applications to physics by examples in quantum field theory, including the standard model of elementary particles and quantum gravity. In particular, we will describe the picture of "quantum spacetime" that emerges from the metric aspect of noncommutative geometry
Berndt Muller Equilibration and Thermalization of Strongly Coupled Field Theories After giving an overview of approaches to the problem of equilibration of isolated quantum systems, I will discuss some recent results on holographic thermalization. Using the AdS/CFT correspondence, we probe the scale-dependence of thermalization in strongly coupled field theories following a quench, via calculations of 2-point functions, Wilson loops and entanglement entropy in 2, 3, and 4 dimensions. In the saddlepoint approximation these probes are computed in AdS space in terms of invariant geometric objects -- geodesics, minimal surfaces and minimal volumes. Our calculations for two dimensional field theories are analytical. In our strongly coupled setting, all probes in all dimensions share certain universal features in their thermalization: (1) a slight delay in the onset of thermalization, (2) an apparent non-analyticity at the endpoint of thermalization, (3) top-down thermalization where the UV thermalizes first. For homogeneous initial conditions the entanglement entropy thermalizes slowest, and sets a time scale for equilibration that saturates a causality bound over the range of scales studied. The growth rate of entanglement entropy density is nearly volume-independent for small volumes, but slows for larger volumes.
Physics with Two Time-like Dimensions This talk will explore the properties of physical theories in space-times with two time dimensions. I show that the common arguments used to rule such theories out do not apply if the dynamics associated with the additional time dimension is thermal or chaotic and does not permit long-lived time-like excitations. I discuss several possible realizations of such theories, including holographic representations and the possibility that quantum dynamics emerges as a consequence of a second time dimension.
Frederic Patras Multiplicative renormalization revisited Multiplicative renormalization addresses the question of how to change the coupling constants of a theory in order to perform, for example, renormalization (cancellation of divergences) or finite renormalization (changing the normalization conditions). The talk will focus on the underlying combinatorial structures, in relation to Rota-Baxter, Faa di Bruno and other algebraic identities. Based on joint works with K. Ebrahimi-Fard.
Bernard Raffaelli Towards a reggeization of Black Holes Physics? From fascination to observation. Beyond the purely mathematical definition of a black hole as a solution of Einstein equations in vacuum, there are some observational clues, as pointed out by Kip Thorne, from the first observation of the binary system Cygnus X1 to recent assumptions related to the presence of hypothetical supermassive black holes in the center of various galaxies, concerning their existence in our Universe and, consequently, encouraging their study. But, what is a black hole? In physics, it is well-known that in order to obtain information on interactions between fundamental particles, atoms, molecules, etc..., and on the structure of composite objects, we have to make collision experiments or, more precisely, scattering experiments. This is exactly the aim of this talk. Indeed, after defining roughly what a black hole is (and is not), studying how it can interact with its environment should allow us to obtain fundamental information about those invisible weird objects. It should be noted that this study is also useful to understand the kind of signals one could detect by the future gravitational waves astronomy devices and, so to speak, to finally have a way to observe directly the presence of a black hole in a given region of our Universe. We will mainly focus on resonance and absorption phenomena of a scalar field by (the quite simple example of) the Schwarzschild black hole. The originality of this study is about the use of an old semiclassical method known as the complex angular momentum theory which brings concepts like S matrix, Regge poles techniques, into high energy black holes physics, as suggested implicitly by Chandrasekhar in the middle of the seventies, in order to understand related properties as the so-called quasinormal modes and the behavior of the absorption cross section. This approach allows us to have simple and quite intuitive physical interpretations of resonance and absorption phenomena, supported by very accurately novel analytical expressions within the framework of a field theory.
Jorgen Vitting Andersen Finance applied to Physics - Physics applied to Finance In the first part of the talk ideas from Finance (rational expectations theory) will be applied to solve a problem in Physics: optimal prediction of failure time of a material. In the second part of the talk ideas from Physics will be applied to understand formation of speculative financial bubbles and systemic risks.