Brans-dicke Theory and Pbh in Early Matter-dominated Era
نویسندگان
چکیده
We have shown that PBHs can be formed in the matter-dominated era if gravity is described by Brans-Dicke theory. Considering an early matterdominated era in between inflation and reheating, we found that the PBHs which are formed during this era lives longer than the standard case where PBHs are formed in early radiation-dominated era. Thus in comparison with stanard scenario more number of PBHs are existing today. Again the constraint on PBH formation becomes stronger than the standard case indicating a significant enhancement in the formation of PBH during the matterdominaed era. PACS numbers : 98.80.-k, 97.60.Lf
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