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: http://www.mso.anu.edu.au/pfrancis/roleplay/html_dir/firstlight/node30.html
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Your main research interests lie in the very first stars and galaxies to form.
Ever since those chaps at Caltech started finding large numbers of galaxies at redshifts up to about 6, the astronomical world has been in a frenzy of theoretical and observational activity. People have flooded into the field from all directions. It is really quite tiresome to work in a field so crowded with parvenues. You, therefore, have turned your interest where nobody else has dared look: to really high redshifts. Nobody has yet found anything more distant than redshift z=5.2, but as theorists, that doesn't stop you. In fact, lack of observational evidence is a positive blessing!
Nobody has seen anything above redshift z=5.2, but there must be
still more distant objects. By redshift 5, you are already seeing
well developed luminous QSOs and radio galaxies, for example. These
need massive black holes to power their activity, and it is hard to
form 
black holes without forming stars and galaxies
around them in the process. These galaxies must have started forming
well before redshift 7. The gas between galaxies is already
very highly ionised at redshift five: this requires vast amounts of
energy, which must have come from somewhere. Furthermore, QSO absorption
lines show that even at redshift 5, large parts of the gas in the universe
have metals: something must have produced all this. The distribution
of fluxes of gamma-ray bursts suggests that many of them too must
have taken place before redshift 5.
So, clearly, lots must have been going on in the dark ages before redshift 5. Why hasn't anybody seen any of this? It may just be too faint, people may have been looking in the wrong way, but most likely, it is just that all the light from things beyond redshift 6 is shifted into the infrared, and infrared detectors are not as sensitive as optical ones yet.
Simple theories suggest that 
objects should have
formed in vast numbers at redshift 
. If they had, the
universe would be full of very old globular clusters and nothing
else, which is manifestly not the case. You are suggesting,
therefore, that as these things form, the first stars created
go supernova and inject so much heat into the gas that it is blown
out of the potential wells (which are defined by the dark matter).
Slowly the gas cools, falling back down
the potential wells until, Poof! it is all blown out again, leaving
a few more neutron stars and low mass stars.
Meanwhile, low-level star formation may be taking place throughout the universe: these so-called Population III stars enrich the inter-galactic medium with metals and help ionise it. Eventually, by redshift 10 or thereabouts, recognisable galaxies start to form. Only small ones, mind you, but they will repeatedly merge together until some fairly large ones have formed by redshift 5, ready for the observers.