If neutrinos do travel faster than light..........

[Nillchill]

Seconded

so how come exotic dark energy is enough to avoid a "big crunch" ?

dark energy is attributed to the cause to the rapid expansion and acceleration of the universe as a whole.

any particle, can be supremely small, the issue with the mass dilation equation is not that the effect of mass when accelerating close to the speed of light is such that its inertia tends toward infinity, m / root ( 1-v^2/c^2) hence you have to put in more and more energy. since the expression ( 1-v^2/c^2) tends to 0

[Ptarmigan]

dark energy is attributed to the cause to the rapid expansion and acceleration of the universe as a whole.

Yes exactly so.

My problem was not with mass dilation but with rest mass.

If the neutrino has non-zero rest mass then the universe will suffer gravitational collapse into a big crunch/black hole (and beyond too?!), unless there is a big inflationary force/cause. (Inflationary is an unfortunate limit of language cos it is already tied to another early universe anomaly.)

So, the upper limit to the mass of the neutrino must have an effect upon the presumed expansionary effect of dark energy (or viceversa) to push Omega over equilibrium ?

EDIT later : or did I mean under equilibrium !? My heads hertz, time for bed said Zebedee

[George Jones]

Yes exactly so.

My problem was not with mass dilation but with rest mass.

If the neutrino has non-zero rest mass then the universe will suffer gravitational collapse into a big crunch/black hole (and beyond too?!), unless there is a big inflationary force/cause. (Inflationary is an unfortunate limit of language cos it is already tied to another early universe anomaly.)

So, the upper limit to the mass of the neutrino must have an effect upon the presumed expansionary effect of dark energy (or viceversa) to push Omega over equilibrium ?

EDIT later : or did I mean under equilibrium !? My heads hertz, time for bed said Zebedee

Experimental evidence indicates that neutrinos have small non-zero rest masses, so small that neutrinos have negligible effect on the expansion of the universe.