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Abstract:

We present a new scenario for baryogenesis in the context of heterotic brane-world models. The baryon asymmetry of the universe is generated at a small-instanton phase transition which is initiated by a moving brane colliding with the observable boundary. We demonstrate, in the context of a simple model, that reasonable values for the baryon asymmetry can be obtained. As a byproduct we find a new class of moving-brane cosmological solutions in the presence of a perfect fluid. © 2002 The American Physical Society.

Abstract:

The effective action for five-dimensional heterotic M theory in the presence of five-branes is systematically derived from HoÅ™ava-Witten theory coupled to an M5-brane world-volume theory. This leads to a five-dimensional N=1 gauged supergravity theory on S¹/Z2 coupled to four-dimensional N=1 theories residing on the two orbifold fixed planes and an additional bulk three-brane. We analyze the properties of this action, particularly the four-dimensional effective theory associated with the domain-wall vacuum state. The moduli Kähler potential and the gauge-kinetic functions are determined along with the explicit relations between four-dimensional superfields and five-dimensional component fields. ©2002 The American Physical Society.