Narrow Results

We review a new paradigm for baryogenesis in which the fundamental Lagrangian is baryon conserving [invariant under U(1)_B]. At high temperatures, U(1)_B is spontaneously broken and an excess of quarks over antiquarks of 10⁻¹⁰s (s≡entropy density) is produced. Today, U(1)_B is restored. A fundamental consequence of our assumptions is that the baryon number of the Universe is constant. If initially zero, it will be zero today. The excess baryon number produced in the quark fields is exactly compensated by antibaryon number in a weakly interacting scalar particle. We suggest that this scalar provides the mass density necessary to close the Universe.

The notion that dark halos are composed of exotic elementary particles grew out of the exchange of ideas between particle theory and cosmology. Direct detection of these particles requires further input from the field of Galactic dynamics. I will explore this connection and also describe a new set of self-consistent, multi-component models for disk galaxies.

Terrestrial WIMP and axion detection experiments probe the local velocity-space distribution of dark matter particles. We review the theoretical approaches that have been used to model this distribution. We then describe a new method, to be combined with standard cosmological N-body simulations, that allows one to extract a local velocity-space distribution function in exquisite detail. Preliminary results and implications for direct detection experiments are discussed.