On Friday, August 29, 2025 at 5:15:32 AM UTC-6 John Clark wrote:
On Fri, Aug 29, 2025 at 2:09 AM Alan Grayson <[email protected]> wrote: *> As I recall, you made the emphatic claim, at least twice, that in the very early universe (but after the galaxies formed), that the galaxies were closely situated, and receded from each other at low velocities. I do NOT recall any proof of concept.* *A**stronomers have observational evidence that the universe started to accelerate about 5 billion years ago, 9 billion years after the big bang.* *It started to accelerate, OR was already accelerating 5 billion years ago, and then accelerated more? This is important for your argument, but I've never heard that before -- that's there's EVIDENCE for your claim (that it STARTED to accelerate 5 billion years ago). AG* * If something is accelerating that means it's getting faster. Therefore 5 billion years ago, before that acceleration started, galaxies must've been moving away from each other slower than they are now. * *> **On the other hand, I gave a basic argument that in fact the rate of recession had to be rapid at that time, since it's now between 67 and 73 km/sec/mpsec, and was SLOWED since that time by gravity, which, last I heard is attractive. **so it would slow the rate of expansion.* *Have you also heard that there is a thing called "Dark Energy"? I've said all this before but I'll say it one more time. We don't know much about it but one of the few things we do know is that Dark Energy is a repulsive force which means it causes things to SPEED UP. Most think Dark Energy is a property of space itself, that's why for the first 9 billion years of the universe's existence Dark Energy didn't have much effect on things, back then the speed of recession between galaxies was slowing down due to gravity just as you'd expect. But as the galaxys expanded the density of matter decreased, and therefore the force of gravity trying to slow things down also decreased. * *Dark Energy may or may not exist, but if it does and is responsible for the speeding up, it doesn't imply the galaxies were receding from each other slowly before DE speeded the expansion. The receding could have been slow before DE became a factor, OR it could have been receding rapidly and that rate was increased by DE. IOW, we just don't know whether the expansion started slowly or rapidly. AG * *However, the expansion of space means more space is being created, and if Dark Energy is a property of space itself then, unlike gravity, it is NOT being diluted. The force of Dark Energy trying to speed things up remained constant, but the force of gravity, trying to slow things down, kept getting weaker because the density of matter kept getting lower. Dark Energy became stronger than gravity 5 billion years ago and remains stronger to this day. * *> I'd be interested in seeing again what you claim was your proof. AG * *As I've mentioned before, a scientist can prove that something is wrong and he can show that something is probably right, but proving that something is absolutely correct can only be found in the realm of pure mathematics, not in physics or in any other branch of science. * *Actually, sometimes even in pure mathematics we can't always reach absolute conclusions, a good example of which is the CONTINUUM HYPOTHESIS. AG* *4vr* -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/everything-list/5180b5f5-7422-4ba5-a32b-3a212986dfe0n%40googlegroups.com.
