## 2012 Workshop Details## WORKSHOPS - SUMMER 2012## * denotes the organizer responsible for participant diversity in the workshop
Over the last 30 years cosmological inflation has emerged as the most popular scenario that explains the origin of the primordial seed fluctuations. While current measurements from the cosmic microwave background (CMB) and large-scale structure (LSS) confirm that the spectrum of primordial fluctuations is Gaussian to a remarkable one part in a thousand, that bound is still several orders of magnitude away from testing primordial non-Gaussianity at the level predicted by slow–roll inflation, and about one order of magnitude above the level expected from non-linear post–inflationary processing of the fluctuations. The contraints on deviations from Gaussianity will improve dramatically in the near future, driven both by CMB and LSS data. A detection of primordial non-Gaussianity would open a new and extremely informative window on the physics of inflation and the very early Universe. Maximizing the potential of discovery for large new data sets, and interpreting their results, are challenging tasks that require the development of new analysis techniques as well as theoretical modeling. This will necessitate close contact between inflationary model builders, phenomenologists and observers. This workshop aims at fostering and strengthening these ties. In addition to broadly accessible overviews of all aspects of primordial non-Gaussianity, the workshop will allow a significant amount of time for informal discussions and the development of new research collaborations.
Greg Stephens, Princeton University The idea of the workshop stems from the understanding that the role of physics in
biology is broad, as physical constraints define the strategies and the biological machinery that living systems use to shape their behavior in the dynamic, noisy, and resource-limited
physical world. To date, such holistic, physics-driven picture of behavior has been achieved, arguably, only for bacterial chemotaxis. Can a similar understanding emerge for other,
more complex living systems? To begin answering this, the workshop will bring together a diverse group of scientists, from field biologists to theoretical physicists, broadly
interested in animal behavior. We would like to broaden the horizons of physicists by inviting experts who quantify behavior of a wide range of model organisms, from
molecular circuits to mammals. We would like to
explore behavior as possibly optimal responses given the physical and the statistical structure of environment. Our topics will include, in particular, navigation and foraging, a
ctive sensing, locomotion and rhythmic behavior, and learning, memory, and adaptive behaviors.
Feedback processes in galaxies are widely believed to have an important role in galaxy evolution. Feedback from nuclear super–massive black holes (SMBHs) has been advocated as a major ingredient in reconciling cosmological simulations to the observed properties of galaxies at different redshift, by dampening/quenching active star formation. Feedback from supernovae is clearly important in the heating and chemical enrichment of the ISM, producing the X–ray signatures detected with Chandra in mergers, starburst galaxies, and elliptical galaxies. Most recently, it has been discussed that even feedback from active X–ray emitting binaries may have an effect on the evolution of galaxies. While the average energy input of these processes can be estimated, the detailed physical processes responsible for the transfer of energy to the host galaxies and their components have not been satisfactorily addressed. Energetically, SMBH accretion can easily supply sufficient energy to unbind the ISM of a galaxy, and so stop star formation. Whether AGNs actually do quench star formation however is unclear. Similarly, current merging simulations do not easily reproduce the observational evidence for X–ray hot, structured and metal enriched halos in mergers. Most simulations use feedback as an input parameter, but have not tried to model the physics of this process. Recently, thanks to high–resolution observations, from radio to X–rays, the physics of feedback has begun to receive more attention, and the current situation is rapidly evolving with exciting prospects for progress and improved understanding. This summer Aspen workshop will be confronting the issues involved and addressing futures approaches, both theoretical and observational, that will produce a better understanding of the detailed physical processes responsible for shaping the evolution of galaxies. Topics will include: 1) The need for feedback in galaxy evolution – latest update from simulations and observations 2) AGN feedback 3) Stellar evolution and feedback: 4) Future outlooks for theory, observations, and instrumentation
Stochastic processes can be used to model systems in which two or more spatio-temporal scales interact. Turbulent flows, weather, and climate are
prime examples. Typically, the small/fast scale is treated as a random influence on the large/slow scale. The workshop will focus on improved understanding of
geophysical and astrophysical flows made possible by stochastic modeling. In particular, advances in computing power and
algorithms permit a direct comparison of stochastic models to numerical simulations. The power and limitations of the stochastic approach need to be better
established, however. The tension between simple and complex models will be explored within the context of how stochastic approaches can address the
enormous range of spatial and process scales inherent in flow and climate systems. The workshop will bring together climate scientists, astrophysicists,
applied mathematicians, and physicists to stimulate interdisciplinary research in these directions.
New methods and exact results have introduced a rich new playground for formal development in our understanding of gauge theories, especially those with supersymmetry. This workshop will emphasize localization techniques, supersymmetric indices, non-perturbative dualities, relations between field theories in different dimensions, measures of the number of degrees of freedom, and related topics. The aim of the workshop is to build on the recent formal progress, explore its consequences, and look for its connections and applications to specific physical models. To give a sense of the breadth and inter-related nature of these developments, recall that localization reduces the Euclidean path integral of supersymmetric gauge theories to a matrix model integral over a finite number of degrees of freedom. Localized path integrals of three dimensional gauge theories on a three sphere exhibit interesting symmetries that have been used to support long-standing non-perturbative duality conjectures and to find new such dualities. These matrix models have also been used to confirm certain detailed predictions of the Anti-de Sitter/Conformal Field Theory correspondence. It has been argued in certain supersymmetric field theories that the scaling dimensions of composite operators are determined by maximizing the free energy F on the 3-sphere. Like the Weyl anomaly coefficients in even-dimensional conformal field theories, F may provide a measure of the number of degrees of freedom in three dimensions. These measures are also connected with properties of the quantum entanglement entropy. A recent proof of the a-theorem in 4-d field theory adds further focus to research on understanding measures of degrees of freedom and their evolution under renormalization group flows.
Particle physics is at a defining moment. The Large Hadron Collider (LHC), after decades of anticipation, is finally collecting data in earnest, running at 7 TeV collision energy. By next summer, the experiments are expected to have data samples on the order of 10,000 pb–1. Once this data is processed and analyzed, we will truly begin to explore the mechanism of electroweak symmetry–breaking. In particular, the data will be sufficient to find evidence for or discover the Standard Model Higgs over most of the preferred mass range, and/or explore many alternative models of electroweak symmetry–breaking. This is a unique opportunity for an Aspen workshop to contribute to â€śrewriting the bookâ€ť of fundamental particles based on the results of the LHC. The purpose of this workshop is to bring together experts in diverse areas including experimentalists, phenomenologists, and model builders, in order to synthesize the results of the LHC data into a coherent picture.
This workshop will bring together a mix of workers from across theory, experiment, and numerical modeling, working on a broad range of systems which exhibit large fluctuations and collective behavior in their mechanical response. It will promote interactions between
participants from condensed matter / statistical physics and researchers at the boundary of physics and other disciplines such as materials science and solid mechanics. The workshop will be organized around three primary physical phenomena: 1) yielding in glassy materials, 2) dislocation dynamics and 3) fracture and fragmentation. The primary aim of the workshop will be to catalyze interactions between researchers to port common theoretical and analytical tools across the problem domains, and to connect theory with experiments.
With several inverse femtobarn of LHC data allowing a detailed probe of electroweak symmetry breaking, a Standard Model Higgs will have been discovered or disproven, new physics will be discovered or increasingly constrained, and the status of the Standard Model will be under intense investigation. Simultaneously, dark matter direct and indirect detection experiments will provide an orthogonal probe of weak-scale interactions. Assembling a consistent description of the emerging picture of the weak scale is the focus of this workshop. Participation by experimentalists is highly encouraged.
This workshop will bring together researchers in physics, computer science, and mathematics to study complex and disordered systems. Systems in all three research areas share common features, such as complex free energy landscapes resulting from frustration, phase transitions, subtle correlations, and jamming. In physics, these systems include amorphous and ordered packings, spin glasses and random field magnets, glassy or amorphous systems with frozen-in disorder, pinned fluid interfaces, colloids, RNA folding, and dense packings of hard particles. In computer science, they include satisfiability, graph coloring, error-correcting codes, compressed sensing, and inference and learning problems. New approaches to these problems include belief propagation, high-temperature duality, permanent-determinant methods, and max-flow/min-cut algorithms. These algorithms can provide results on complex disordered systems that are inaccessible to both experiment and previous theoretical approaches. Moreover, many of these algorithms have interesting dynamics in their own right; they are based on a deep conceptual understanding of the physical system, and help advance that understanding. * Organizer in charge of Diversity For more information about the Aspen Center for Physics, call (970) 925-2585 or email acp at aspenphys. org. |