We outline a scenario of galaxy formation in which the gas in galaxy-forming regions was preheated to high entropy by vigorous energy feedback associated with the formation of stars in old ellipticals and bulges and with AGN activity. Such preheating likely occurred at redshifts z ∼ 2 – 3, and can produce the entropy excess observed today in low-mass clusters of galaxies without destroying the ...

We study F -term hybrid inflation in a novel supersymmetric extension of the SM with a subdominant Fayet–Iliopoulos D-term. We call this particular form of inflation, in short, FD-term hybrid inflation. The proposed model ties the μ-parameter of the MSSM to an SO(3)-symmetric Majorana massmN , through the vacuum expectation value of the inflaton field. The late decays of the ultraheavy particle...