14th International Symposium on Particles, Strings and Cosmology (PASCOS '08)
Lattice QCD in this decade has succeeded in producing essential results for crucial components of Standard Model phenomenology such as constraints on the rho-eta plane. Much more will be required of lattice gauge theory in the LHC era: sub-per cent precision in QCD quantities and the ability to calculate in strongly interacting sectors of Beyond-the-Standard-Model theories such as SUSY or technicolor. I will review the status of current calculations and the prospects for accomplishing what needs to be done in the coming years.
The Higgs boson is the only scalar particle in the Standard Model. Precision electroweak analyses suggest that it should be light -- less than 200 GeV. These facts combined with the speculative nature of all electroweak symmetry breaking discussions imply significant uncertainty in discovering a Higgs boson. I discuss the unique aspects of a Higgs sector, highlight the New Physics origins of uncertainty for its phenomenology, and suggest a broader framework with which to approach Higgs boson phenomenology at the LHC.
We formulate non-anticommutative supersymmetry in two dimensions using differential operators acting on the component fields. We then use these operators to give a compact expression for the one-loop divergences in the non-anticommutative Kahler sigma model.
The smaller Dark Matter structures predicted in the CDM scenario have a mass in the range [10e-12;10e-4] Msun, depending on the underlying particle physics. It is however not clear what is the inner DM structure of such halos, nor which is the real survival probability during mergers. We show how these open questions result in a large uncertainty in the prediction of the observability of such halos with indirect detection tecniques.
If the spontaneous breaking of Peccei-Quinn symmetry comes from soft supersymmetry breaking, the fermionic partners of the symmetry-breaking fields have mass of order the gravitino mass, and are called flatinos. The lightest flatino, called here the flaxino, is a CDM candidate if it is the lightest supersymmetric particle. We here explore flaxino dark matter assuming that the lightest ordinary supersymmetric particle is the stau, with gravity-mediated supersymmetry breaking.
\'Thermal history of the universe after big-bang nucleosynthesis (BBN) is well understood both theoretically and observationally, and recent cosmological observations also begin to reveal the inflationary dynamics. However, the epoch between inflation and BBN is scarcely known. In this work we show that the detection of the stochastic gravitational wave background around 1Hz provides useful information about thermal history well before BBN.
It is an important task to embed inflation in a fundamental microphysical theory such as string theory. Since string theory possesses a vast landscape of 4-dimensional theories, we would like to know which portions contain inflation and which do not. I prove a no-go theorem that inflation and de Sitter vacua are forbidden in an exponentially large number of infinite families of simple and well understood compactifications of type IIA string theory.
Directional detection of dark matter can provide unambiguous observation of dark matter (DM) interactions even in the presence of insidious backgrounds. The DM-TPC collaboration is developing a detector with the goal of measuring the direction and sense (\'\'head-tail\'\') of nuclear recoils produced in spin-dependent DM interactions. The detector consists of a low pressure TPC with optical readout filled with CF4 gas at low pressure. A collision between a WIMP with a gas molecule results in a nucleus recoil of 1-2 mm.