Another attempt to avoid big bang

Evgenii Lifshitz and Isaac Khalatnikov (russians) suggested that big bang might be a peculiarity of Friedmann's modes, which were approximations. 

In the real universe, however, the galaxies are not just moving directly away from each other - they also have small sideways velocities. So in reality they need never have been all at exactly the same place, only very close together. 

Perhaps then the current expanding universe resulted not from a big bang singularity, but from an earlier contracting phase; as the universe had collapsed the particles in it might not have all collided, but had flown past and then away from each other, producing the present expansion of the universe.

What they did was study models of universe roughly similar to Friedmann's but took account of the irregularities and random velocities of galaxies in real universe. 

They showed that such models could start with a big bang, even though the galaxies were no longer always moving directly away from each other, but they claimed that this was still only possible in certain exceptional models in which the galaxies were all moving in just the right way. They argued that since there seemed to be infinitely more Friedmann-like models without a big bang singularity than there were with one, we should conclude that there had not in reality been a big bang. They later realized, however, that there was a much more general class of Friedmann-like models that did have singularities, and in which the galaxies did not have to be moving any special way. They therefore withdrew their claim in 1970.

The work of Lifshtiz and Khalatnikov was valuable cuz it showed the universe *could* have had a singularity, a big bang, if the general relativity was correct. 

But it still was crucial whether GR predict our universe *should* have had a big bang, a beginning of time.