Non-singular model of universe

Einstein equations give minimum and maximum limits of cosmic scale factor by considering pressure. in oursuggested model the contraction before expansion of cosmos is like the birth of a star. as in nuclear fusionstage, the temperature and pressure of the star depends on its mass, in the order of magnitude of universemass fusion after gravitational contraction brings about explosion. this does not require to accept the big bangsingularity. explosions have thrown external layers and formed parts of the expanding cosmos in several stages.we dealt with the problem of horizon by considering the idea of step- by step explosions. in observable part ofthe universe high percentage of dark energy and dark matter confirms that these are the remains of other partsof the cosmos. neutrinos being highly energetic and without any interaction are the most suitable candidates fordark energy and massive black holes being found at the central part of galaxies and in stellar clusters are themost suitable candidates for dark matter.