Zanket Posted November 18, 2006 Posted November 18, 2006 Itll get you references later, I have my exams this week and its been about 4 years since i've read that information, cant remember where. But i believe entropy is also an issue for a universe that has existed for an infinite amount of time, surely. Even if not entropy, how about thermal eqilibrium? How does an eternal universe aviod that? I’ll await your references on this point, if only because I don't have time to research this now. Should the night sky be fully illuminated, seeing as the light from the most distant stars have reached us by now? That’s Olbers’ paradox, covered in section 7. And why favour an infinite amount of 1 diemension, time, and not space? they are the same. You are not claiming space is finite are you? Then how would it expand/contract as you say? Section 7 says about the new cosmological model, “The universe has always been infinite in extent.” Unlike for cosmological models based on GR, both time and space are always infinite in any direction my model.
D H Posted November 18, 2006 Posted November 18, 2006 Sorry for the confusion. I misread Farsight's question. The velocity of any object as measured by some observer does not exceed the speed of light. Period. It doesn't matter if the object or observer is accelerating.
Zanket Posted November 18, 2006 Posted November 18, 2006 The velocity of any object as measured by some observer does not exceed the speed of light. Period. It doesn't matter if the object or observer is accelerating. True. Above you said: The tip of the rocket can get to the ball and star in an arbitrarily short period of time because the distance to the star can be made arbitrarily small in the crew's frame by making the relative velocity approach that of light. In this case you didn't think that anything exceeds c. Nothing moves faster than c in (b) for the same reason. Extend the rocket so that its tip is initially at the star. Leave a mark on the rocket where the tip was. Then by your own reasoning it is apparent that the star can traverse from the tip of the rocket to the mark in an arbitrarily short time in the crew's frame, regardless of the proper distance between the tip and the mark. You are stuck on the idea that if the star or ball is traversing empty space, it need not exceed c for the crew's time to be arbitrarily short, whereas if it is traversing the rocket, it must exceed c to do that. But it doesn't matter whether the gap between the mark and the star is empty or the rocket fills it. When the rocket fills the gap, the distance between the mark and the star can still be made arbitrarily small in the crew's frame by making the relative velocity approach that of light.
D H Posted November 19, 2006 Posted November 19, 2006 ... regardless of the proper distance ... Do you know what proper distance is? Your usage implies that you think there is some absolute reference frame in which things are measured "properly".
Zanket Posted November 19, 2006 Posted November 19, 2006 Yes. It doesn't imply that. I could have said "regardless of the initial distance between the star and the mark in the crew's frame". That's the same distance as the "proper distance between the tip and the mark". I'm just referring to a specific distance using the fewest words. Why do you think that the time elapsed in the crew's frame is affected by whether the star traverses empty space or traverses the rocket?
Farsight Posted November 20, 2006 Posted November 20, 2006 How about this one guys: http://forum.physorg.com/index.php?showtopic=10697
Zanket Posted November 22, 2006 Posted November 22, 2006 How about this one guys: AlphaNumeric is correct there in that velocity can be accurately measured only locally, ideally in the limit of zero distance traversed. I pointed that out above in this thread.
Farsight Posted November 22, 2006 Posted November 22, 2006 OK thanks Zanket, I agreed after I thought it through. Sorry, but I'm struggling with that introduction to your paper - on how the ball can traverse the vertical length of the rocket in an arbitrarily short time as far as the crew are concerned. If you could rephrase it in some way I'd be grateful.
Zanket Posted November 22, 2006 Posted November 22, 2006 Sorry, but I'm struggling with that introduction to your paper - on how the ball can traverse the vertical length of the rocket in an arbitrarily short time as far as the crew are concerned. You gave the reasoning on that above. It's the same reasoning used to see that they can get to any free object (e.g. a star) in that time. When they're at the bottom of the rocket, the star gets to them by traversing the rocket first. The ball can be treated like a star. If you could rephrase it in some way I'd be grateful. OK, I've got some ideas on that. Maybe in a few days.
Ragib Posted November 23, 2006 Posted November 23, 2006 Could I just please know that if the universe has always been infinite in extent, how exactly is the cosmic background radiation explained by your model? Shouldn't that be infinitely red shifted as well?
Zanket Posted November 23, 2006 Posted November 23, 2006 Could I just please know that if the universe has always been infinite in extent, how exactly is the cosmic background radiation explained by your model? Shouldn't that be infinitely red shifted as well? In my model the finite redshift of the CMBR can be explained by it sourcing from the beginning of the current phase of expansion of the universe, happening a finite time ago, hence the CMBR we see now sources from a finite distance away from us, just as it does in the leading model. In the leading model the CMBR sources from the big bang (or shortly thereafter), a finite time ago when any given patch of the universe was contained in zero volume (a singularity). In my model the current phase of expansion of the universe began from a finite time ago when any given patch of the universe was contained in a volume that can be arbitrarily small but not zero. In other words the expansion began from an event that can be exceedingly similar to the big bang.
Zanket Posted November 26, 2006 Posted November 26, 2006 Sorry, but I'm struggling with that introduction to your paper - on how the ball can traverse the vertical length of the rocket in an arbitrarily short time as far as the crew are concerned. If you could rephrase it in some way I'd be grateful. I rephrased it here.
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