Re: Does the 1a Supernova Project disprove the expanding universe theory?

Hi George,

The Supernovae Project does not disprove the expanding Universe theory. On the contrary, it provides evidence that perhaps the Universe is increasing its rate of expansion. I'm not sure what you mean by "The 1a Supernovae project... showes the observed time of the supernovae to be the same for redshifts z=0.32 to z=0.83." If by "observed time" you mean how long each supernova lasts, what I see when I read their results, both in the papers they've written and at the website ( http://supernova.lbl.gov) is that the duration of a type 1a supernova depends on how bright it is, and that, *after correction for the expansion of the Universe*, the duration turns out to be proportional to the brightness. The fact that the times and brightnesses match up only after correcting for the expansion suggests that the Universe is in fact expanding. If by "observed time" you mean the day and hour at which the supernovae explodes, the times appear to be completely random, and have nothing to do with the expansion of the Universe.

The standard Big Bang model predicts that the Universe is expanding, but the expansion is gradually slowing down. Using this theory, if you look at very distant supernovae, you expect them to be fainter (because they're farther away) and you expect them to be moving away from us (visible as a Doppler "redshift", which you can find described elsewhere in the Mad Scientist archives) because the Universe is expanding. Light takes time to travel, so when you look at really distant objects you're looking at light that left a long time ago (sort of like looking back in time). Since the expansion is supposed to be slowing down, the ones that are extremely far away (from a long time ago) should have been moving even faster than what you'd expect based on today's expansion rate. What the supernovae results appear to show is that the really distant supernovae have a little *less* redshift than expected, meaning that perhaps the expansion of the Universe has been speeding up, rather than slowing down. If these results turn out to be correct, they show that the Big Bang model needs to be modified a little to include an *increasing* expansion rate, but they certainly don't fit with a model in which the Universe is not expanding at all.

I hope this helps. There's a pretty readable description of the supernovae project at http://www.lbl.gov/supernova and it contains links to further, more detailed explanations. You could contact me by E-mail at stevenlevin@we.mediaone.net if you want to discuss any of this further.