ABSENCE OF A LOWER LIMIT ON OMEGA(B) IN INHOMOGENEOUS PRIMORDIAL NUCLEOSYNTHESIS

We show that a class of inhomogeneous big bang nucleosynthesis models exist which yield light-element abundances in agreement with observati onal constraints for baryon-to-photon ratios significantly smaller tha n those inferred from standard homogeneous big bang nucleosynthesis (H BBN). These inhomogeneous nucleosynthesis models are characterized by a bimodal distribution of baryons in which some regions have a local b aryon-to-photon ratio eta approximate to 3 x 10(-10) while the remaini ng regions are baryon depleted. HBBN scenarios with primordial (H-2 He-3)/H less than or similar to 9 x 10(-5) necessarily require that mo st baryons be in a dark or nonluminous form, although new observations of a possible high deuterium abundance in Ly alpha clouds may relax t his requirement somewhat. The models described here present another wa y to relax this requirement and can even eliminate any lower bound on the baryon-to-photon ratio.