Kathryn Miknaitis, University of Chicago

In 2001 (and more definitively in 2002), the Sudbury Neutrino Observatory (SNO) experiment demonstrated that electron neutrinos produced in the solar interior were changing flavor prior to reaching the earth. SNO's measurements of solar neutrino flavor change conclusively solved the long-standing "Solar Neutrino Problem" and provided evidence for the existence of neutrino mass. Far from being the end of the story, these and other recent neutrino physics results have opened up a rich field of fundamental questions to be probed by current and future experiments. I will give an overview of several of the major open questions in neutrino physics and discuss how SNO's recent and ongoing measurements fit into the bigger project of unraveling the neutrino's mysteries.

Mark G. Jackson, Fermilab

I will discuss the recent developments suggesting that cosmic superstrings are theoretically possible, and observationally distinct from conventional cosmic strings. First reviewing the appearance of cosmic strings in string theory and some models of inflation therein, I show how their formation can still be consistent with existing CMB/pulsar bounds. I then profile methods by which cosmic strings can be detected. Finally I will explain how to differentiate cosmic superstrings from conventional vortex cosmic strings, and how this can be used to extract information about string parameters and extra dimensions.

Jonathan Feng, University of California, Irvine

Recent breakthroughs in cosmology indicate that a quarter of the Universe is composed of dark matter, but the microscopic identity of dark matter remains a deep mystery. I will review recent progress in resolving this puzzle, focusing on two well- motivated classes of dark matter candidates: WIMPs and superWIMPs. In each of these classes, stable particles are naturally produced in the early Universe with the right relic density to contribute to dark matter, and dark matter particles have mass around 100 GeV, the energy scale soon to be probed in detail at particle colliders. I will discuss the theoretical motivations for these possibilities, their diverse implications at the interface of particle physics, astroparticle physics, and cosmology, and the prospects for identifying dark matter in the coming years.

Alexia Schulz, University of California , Berkeley

Baryon oscillations in the matter power spectrum, used as a standard ruler, have the potential to strongly constrain the expansion history of the universe and the nature of the dark energy. Localizing the features in the galaxy power spectrum and relating them to features predicted in the dark matter spectrum necessitates a theoretical understanding of such complex issues as galaxy bias, non-linear evolution, and redshift space distortions. Using the halo model to analytically investigate these effects, we have identified trends that relate the scale dependance of the galaxy bias to the halo occupation distribution (HOD). These trends reveal a natural parametrization of the galaxy power spectrum. Combining this parametrization with the results of N-body simulations, we have quantified the impact of the HOD parameters on the scale dependance of the galaxy bias. We show that the bias in real space is less profoundly affected by shifts in the HOD parameters, which suggests that baryon oscillation measurments in the correlation function may prove to be more robust to the theoretical uncertainties that are baryon oscillation measurments in the galaxy power spectrum.

Carlos Wagner, Argonne National Laboratory and University of Chicago

Dark Matter candidates abound in models of new physics. The best motivated candidates are associated with extensions of the Standard Model (SM) that provide a natural mechanism for electroweak symmetry breaking. Production of a weakly interacting, neutral, dark matter candidate at hadron and lepton colliders will lead to events with missing energy. In this talk I will discuss the prospects of detecting such dark matter candidates at the Tevatron, the LHC and the ILC.

Peder Norberg, University of Edinburgh

We present detailed clustering measurements for a flux limited sample of ~14,000 quasars extracted from the 2dF QSO Redshift Survey(2QZ) in the redshift range 0.810^12 M_sun and that the mean mass of their host haloes is of the order of 10^13 M_sun. We then split each redshift interval into several luminosity intervals, for which we estimate the quasar projected auto and cross-correlation functions. Fitting the data with a biased CDM model and using several statistical tests, we find that models with luminosity dependent clustering tend to be statistically favoured. However, the quality of the data is not good enough to accurately quantify how quasar biasing depends on luminosity. We critically discuss the limitations of our dataset, as well as the method, and show that a much larger sample is needed to rule out current models for luminosity segregation.

Jose Blanco-Pillado, New York University

Four dimensional effective actions of many of the currently studied extra-dimensional theories seem to contain massless scalar fields called moduli. Giving these fields a potential is crucial to make these theories compatible with observations. It is therefore natural to explore the possibility that before they settle down to the true minimum of their potentials these fields could be relevant for cosmology, in particular they could be the source of an inflationary expansion period of the universe. In this talk, I will review ealier attempts to follow these ideas and present a new model of topological modular inflation in the context of the recently develop flux compactifications within string theory.

Gary Hill, University of Wisconsin, Madison

Since the early 1990's, the South Pole station in Antarctica has been the site of the development and operation of the world's first ice-Cherenkov neutrino telescopes, AMANDA and IceCube. The AMANDA telescope was completed in 2000 and has been used to search for the first high-energy neutrinos from beyond the earth. The successor to AMANDA, IceCube, will be a kilometre-scale neutrino and air shower detector with unprecedented sensitivity to astrophysical sources of neutrinos. In this talk, a summary of the results from AMANDA and report on the first two construction seasons of the IceCube telescope will be given. The prospects for extraterrestrial neutrino observation with the full IceCube array, slated for completion in 2010, will be discussed.

Tom Crawford, University of Chicago

A new millimeter/submillimeter-wave telescope is being constructed for deployment at the NSF South Pole research station. This telescope, with a 10-meter clear aperture, is designed for conducting large area surveys with unprecedented sensitivity to low surface brightness emission such as primary and secondary CMB anisotropy. The first camera for the new South Pole Telescope (SPT) will be a 1000-element bolometer array designed to conduct a blind survey over a few thousand square degrees, searching for galaxy clusters through their Sunyaev-Zel'dovich Effect. The survey should find many thousands of clusters with a selection criterion that is remarkably uniform with redshift. Armed with redshifts obtained from optical/IR follow-up, the survey yields should allow tight constraints to be placed on the equation of state of the dark energy. The cluster survey data will also be used to measure the small-scale primary and secondary CMB power spectra well beyond current limits of sensitivity and resolution, improving our knowledge of the spectrum of primordial fluctuations, the mass of the neutrino, and other cosmological measurables. Finally, a planned polarimeter for the SPT will have the statistical power to constrain the energy scale of inflation through measurement of the B-mode power spectrum of the polarized CMB.

Nemanja Kaloper, University of California, Davis

We will discuss mechanisms which can simulate dark energy with w<-1, but do not use any ghosts, phantoms or other occult beasts.

Jeremy Tinker, University of Chicago

Measurements of the galaxy two-point correlation function create strong constraints on the statistical occupation of galaxies within dark matter halos, referred to as the Halo Occupation Distribution (HOD). Using the HOD, one can make predictions for other clustering statistics for a given cosmology. Recent results have demonstrated a tension between galaxy clustering results and the so-called "concordance cosmology". These results include cluster mass-to-light ratios, galaxy pairwise velocity dispersions, and redshift-space anisotropies. All of these discrepancies are ameliorated if one assumes a cosmology in agreement with the new WMAP year 3 results. This methodology for constraining the HOD relies on the simplifying assumption that halo occupation is a function of halo mass only, independent of the halo's environment. This assumption has been called into question with recent theoretical results. I will present new measurements of void statistics from the SDSS public DR4 database and compare these data to HOD predictions using the standard assumptions. Voids provide a sensitive test for the environmental dependence of halo occupation, a test the HOD passes with flying colors.

Michael Boylan-Kolchin, UC, Berkeley

Several independent lines of evidence indicate that gas-poor mergers play an important role in assembling massive elliptical galaxies. Since low-redshift ellipticals are observed to obey well-defined scaling relations, dissipationless mergers can place interesting constraints on galaxy formation theories. I will present the results of numerical simulations of these mergers, including their locations relative to the observed fundamental plane, Faber-Jackson, and stellar mass-size relations, as well as possible implications for the black hole M-sigma relation in massive galaxies. I will also discuss dissipationless merging in the context of the formation of giant ellipticals and brightest cluster galaxies.

Mark Neyrinck, University of Hawaii

I will discuss explorations, using the halo model, of the information content as a function of scale of the nonlinear dark-matter power spectrum. The halo model gives similar results as Rimes and Hamilton recently found from N-body simulations. Both methods predict a paucity of cosmological information on translinear (k ~ 0.1-1 h/Mpc) scales, which may be partially explained in the halo model by Poisson fluctuations (particularly large for the largest haloes) in halo number density in a given volume. I will also discuss whether information is preserved in time in the halo model, and how halo model parameters might be constrained by requiring that information cannot be created.

Dan Kapner, KICP

I will describe a series of experiments that test the Inverse-Square Law (ISL) down to 65 micron separations. A variety of physics beyond the standard model motivates such a search; the exchange of new bosons, extra dimensions, or even the energy scale of dark energy might lead to a violation of the ISL. Our torsion balance tests set new limits for these scenarios. New results will be presented.

Joel Primack, University of California, Santa Cruz

In this informal talk, I will summarize the large suites of high-resolution hydrodynamic simulations of galaxy encounters that my current and former PhD students have been running and analyzing, and comparisons with observational data especially from the ongoing DEEP2 survey. In particular, I will discuss what the data from DEEP tell us about the morphologies of the galaxies that host AGNs, and the interesting implications for theoretical models. The people involved include my former PhD students T.J. Cox and Patrik Jonsson (who stayed on at UCSC as a postdoc), my current students Greg Novak, Matt Covington, and Christy Pierce, and my former postdoc Jennifer Lotz.

Mark Chen, Queen's University

The Sudbury Neutrino Observatory (SNO) will stop taking data at the end of 2006. The heavy water in SNO will be removed in 2007. What should be done next? By filling SNO with a liquid scintillator (called SNO+) a new, multipurpose detector with diverse physics goals could be a successor. Located in the deepest underground lab, SNO+ would have unique capabilities including detection of pep and CNO solar neutrino. By measuring the flux of pep solar neutrinos, with precision, one can test the neutrino-matter interaction which is sensitive to new physics. SNO+ could also detect geo-neutrinos -- the neutrinos from radioactivity in the Earth -- and is favourably located for such a measurement since it is surrounded by Canadian Shield continental crust, a simple geological configuration. Fundamental questions in geoscience could be addressed by a SNO+ geo-neutrino measurement. Lastly, double beta decay isotopes might be deployed in the liquid scintillator resulting in a competitive next-generation search. The prospects are being studied and SNO+ R&D will be presented.

Olivier Dore, CITA

The Wilkinson Microwave Anisotropy Probe (WMAP) is a NASA satellite designed to produce high resolution full sky maps of the temperature and polarization of the cosmic microwave background (CMB). The accurate characterization of the fluctuations in the CMB contains exquisite information about the global structure, composition, and evolution of the universe. Relying on the first three years of observations, WMAP has now measured these fluctuations with unprecedented accuracy. I will illustrate how a greater signal-to-noise in the temperature measurement but also a new large scale polarization signal detection have significantly sharpened our cosmological interpretation. A simple six-parameters cosmological model (flat LCDM); consisting of baryons, dark matter, a cosmological constant, initial perturbation spectrum amplitude and slope, and optical depth; is an excellent fit to the WMAP data, as well as a host of other astronomical experiments. The new WMAP data also hint at a small deviation from scale invariance in the primordial fluctuation power spectrum, a key prediction of inflation. If confirmed this would strengthen our confidence in the inflationary scenario and allow detailed model testing. Besides, the combination of WMAP data and other astronomical data places even stronger constraints on the density of dark matter and dark energy, the properties of neutrinos, the properties of dark energy and the geometry of the Universe.