Time | Speaker |
---|---|
8:15AM | Breakfast: Coffee/Juice/Muffins/Bagels, 13th Floor Commons |
9:00AM | Welcome/Introductory Remarks |
9:15AM |
Tom Rosenbaum University of Chicago Quantum Spin Glasses |
10:00AM |
Alan Middleton Syracuse University Which Measures of Spin Glass Overlaps are Informative? Reports from Flatland |
10:45AM | Coffee Break, 13th Floor Commons |
11:15AM |
Mike Moore University of Manchester The Almeida-Thouless Line in Spin Glasses For nearly 30 years an argument has raged as to the nature of the low-temperature phase of
spin glasses. There are two main theories. The first is the theory of Parisi which is based upon
the idea that the ordered phase is like that found in mean-field theory: it has a large number of
pure states arranged in an ultrametric topology and has broken replica symmetry, (RSB). For finite
dimensional systems Newman and Stein have modified this picture to the chaotic pair state. The
other theory is that of the droplet model which is based on simple scaling and renormalization
group ideas and has but two pure states, (just as in a ferromagnet). The low-temperature phase
has replica symmetry. |
12:00PM |
Phil Anderson Princeton University Remarks on Supersolidity |
12:45PM | Lunch, 13th Floor Commons |
2:15PM |
Charles Doering University of Michigan Features of Fast Living: On the Weak Selection for Longevity in Degenerate Birth-Death Processes Deterministic descriptions of the dynamics of competing species with identical carrying capacities but distinct birth, death, and reproduction rates predict steady state coexistence with population ratios depending on initial conditions. Demographic fluctuations described by a Markovian birth-death model break this degeneracy. A novel large carrying capacity asymptotic theory confirmed by conventional analysis and simulations reveals a weak preference for longevity in the deterministic limit with finite-time extinction of one of the competitors on a time scale proportional to the total carrying capacity. |
3:00PM |
Mark Dykman Michigan State University Fragility of the Rates of Rare Events We discuss rare events that result from large classical and quantum fluctuations in systems away from thermal equilibrium. They include switching between coexisting stable states in dynamical systems and population (species) extinction in population dynamics and chemical systems. We show that the rates of rare events can discontinuously change with the change of the parameters of the system. Using examples of currently studied physical systems, we discuss the criteria for the onset of fragility, the discontinuous change of the most probable paths followed in rare events, and the associated modification of the conventional analysis of the rates of rare events. This talk is dedicated to Dan Stein, who made an outstanding contribution to the theory of rare events. |
3:45PM | Coffee Break, 13th Floor Commons |
4:15PM |
Michael Damron Indiana University Broken Ergodicity and Invasion Percolation |
5:00PM |
Robert Austin Princeton University The Joys of Being Young and Doomed at Princeton |
5:45PM | Closing Remarks |
6:00PM | End of First Day |
6:45PM | Gala Dinner at Legends Restaurant , 88 7th Avenue, between 15th and 16th Street |
Time | Speaker |
---|---|
8:15AM | Breakfast: Coffee/Juice/Muffins/Bagels, 13th Floor Commons |
9:00AM | Introductory Remarks |
9:15AM |
Daniel Fisher Stanford University Randomness and Evolutionary Dynamics |
10:00AM |
Marija Vucelja New York University Insights from Spin-Glasses in Population Genetics: Emergence of Clones in Populations Population genetics studies how genes and alleles evolve. It is a very important subject and an active field of research. A deep theoretical understanding of population genetics is essential for describing many biological phenomena, and for explaining the genetic diversity that we observe. From the standpoint of physics population genetics represents a complex, interacting, non-equilibrium statistical physics problem and as such is quite challenging, and in many cases yet unsolved and puzzling. My talk is about the emergence of large clones in populations. Clones arise in cases where the selection managed to amplify individual genotypes in spite evolutionary processes that aim to reshuffle the genetic material (recombinations and mutations). The "clonal condensation" is an essential phenomenon, present in many populations, that has not been captured by traditional population genetics measures (such as linkage disequilibrium). I will point out the similarity between the clonal condensation and the freezing transition in the Random Energy Model of spin glasses. Guided by this analogy I will derive one of the key quantities of interest: the probability that two individuals are genetically identical. This quantity is the analog of the spin-glass order parameter, and it is also closely related to rate of coalescence in population genetics: two individuals that come from the same clone have a recent common ancestor. I will summarize of the present understanding of this condensation phenomena. Finally, I will describe future directions in population genetics, linking physics and biology closer together. |
10:45AM | Coffee Break, 13th Floor Commons |
11:15AM |
James Sauls Northwestern University Chiral Superfluid Order in an Anisotropic Glass Random fields coupled to an order parameter describing one or more broken continuous symmetries have been investigated since the early 1970’s - from the destruction of long-range order of the Abrikosov vortex lattice in type II superconductor to ferromagnetism in a materials random magnetic disorder. In this talk I argue that the quantum liquid phases of 3He infused into silica aerogel provide a unique system for studying the struggle between orbital order of Cooper pairs, and disorder characterized by random anisotropy. This competition leads to remarkable new chiral superfluid phases exhibiting broken time-inversion symmetry, space parity, and as I argue, a novel phase that has finite range orientational order in two dimensions, but long range order in a third dimension. This phase is the realization of a biaxial-chiral phase with finite-range orientational correlations due to the random anisotropy field of the aerogel medium. These conclusions are sup- ported by theoretical analysis of the phase diagram and NMR spectra of superfluid 3He infused into anisotropic aerogel. |
12:00PM |
Charles Stafford University of Arizona Probing Maxwell's Demon with a Nanoscale Thermometer Recent advances in thermal microscopy, where spatial and thermal resolutions of 10nm
and 15mK, respectively, have been achieved,^{1} raise a fundamental question, “On how
short a length scale can a statistical quantity like temperature be meaningfully defined?”
We tackle this question theoretically^{2} by first providing a physically motivated and
mathematically rigorous definition of an electron thermometer as an open third terminal
in a thermoelectric circuit. We then develop a realistic model of a scanning thermal
microscope (SThM) with atomic resolution, operating in the tunneling regime in ultrahigh
vacuum, including the thermal coupling of the probe to the ambient environment. With
this model of an electron thermometer, we investigate the temperature distributions in
molecular junctions,^{2} and graphene nanoribbons^{3} under thermal bias. We find that the
temperatures of individual atomic orbitals (or bonds) in these systems exhibit quantum
oscillations; quantum interference mimics the actions of a Maxwell Demon, allowing
electrons from the hot electrode to tunnel onto the temperature probe when it is at
certain locations near the molecule, and blocking electrons from the cold electrode, or
vice versa. A crossover to a classical temperature distribution consistent with Fourier’s
law of heat conduction is predicted as the spatial resolution of the temperature probe is
reduced. |
12:45PM | Lunch, 13th Floor Commons |
2:15PM |
Louis-Pierre Arguin University of Montreal The Mathematics of Short-range Spin Glasses: Some Proofs and (Many) Open Problems The rigorous understanding of the structure of mean-field spin glass models have undergone tremendous progress in the last fifteen years. This is to be compared with the finite-dimensional models where many questions remain open. In this talk, I will survey results on short-range spin glasses that were obtained by Dan Stein and collaborators over the years that aim to answer some of these questions and to shed light on the low-temperature behavior of these models. |
3:00PM |
Pierluigi Contucci University of Bologna Quenched Diluted Models with Hardcore Interactions The seminar will introduce the quenched diluted models of monomer-dimer type. The deterministic case and its properties, solved by Heilmann and Lieb, will be reviewed. The diluted version exact formula, found within the replica symmetric cavity approach, will be rigorously proven. The model turns out to have an analytic pressure whose monomer density is explicitly identified by the expectation of the solution of a ﬁxed point distributional equation. Joint work with Diego Alberici. |
3:45PM |
Gerard Ben-Arous New York University Randomly Trapped Random Walks I will describe a very general scheme of trapping for random walks on graphs, which contains the usual Fractional Kinetics or Bouchaud Trap models as simple examples. A full study of their possible scaling limits in dimension 1 will be given. This will be applied to the case of the scaling limit of the RW on incipient infinite cluster on critical trees, and on invasion percolation clusters on trees. This work was started long ago in the PhD thesis of Roman Royfman and has been completed only recently in a joint work with Jiri Cerny and Manuel Cabezas. |
4:30PM | Conclusion |
4:45PM | Closing Reception, 13th Floor Commons |