The cosmic ray results indicate that there is not significant quantity of antimatter objects within a radius 1 Mpc. Gama ray flux measurements exclude significant amounts of antimatter up to the distance of galaxy cluster scales ~ 10 -20 Mpc.

However, the cosmic ray and gama ray data do not rule out large antimatter domains on larger scales, or small ratios of antimatter/matter objects on small scales, like antimatter stars, antimatter globular star clusters in our Galaxy as well as antimatter galaxies in between the clusters of galaxies.

Theoretically, there exist inhomogeneous baryogenesis scenarios predicting naturally the production of antimatter regions or objects in our Universe. We explore numerically an inhomogeneous baryogenesis model, based on scalar condensate baryogenesis scenario, predicting naturally the formation of different antimatter structures in the Universe.

We have collected all experimental data, available from experiments on balloons and on spacecraft , for antinuclei and antiprotons in cosmic rays. The figure presents the antiproton data from BESS, MASS and CAPRICE experiments compared with different

models predictions for secondary antiprotons. The comparison with theoretical predictions for secondary antiprotons the does not exclude the possibility for a small fraction of primordial antiprotons.

Recent publications:

D.Kirilova, BARYOGENESIS MODEL PREDICTING ANTIMATTER IN THE UNIVERSE,

talk at XII Int. Symposium "Very High Energy Cosmic Ray Interactions",

15 - 20 July 2002, CERN, Geneva, Switzerland, in *Geneva 2002, Very

high energy cosmic ray interactions* 404-408 and

Nucl. Phys. Proc. Suppl. v. 122, pp. 404-408, 2003.

D.Kirilova, M.Panayotova, T.Valchanov, Vast antimatter regions and

SUSY-condensate baryogenesis, Proc. XIVth Rencontre de Blois

"Matter-Antimatter Asymmetry", ed. J. Tran Thanh Van, p.439-442.

Kirilova D., Baryogenesis Model Suggesting Antigalaxies, Astronomical &

Astrophysical Transections, 1998, v.15, p. 211.