owl

If space is emptiness as distinguished from the "stuff" existing in it, then it (space) is not a medium which can expand, have shape, etc. This goes back to the "square one" ontological question, "what is space if not just emptiness or infinite "volume?" So, I see the "bang" (by whaterver dynamic) "launching" all cosmic "stuff" outward omni-directionally, so the further out things get, the further they are from each other and from the locus of the bang. I know that "expanding space" is now mainstream science, but the ontological question as to what, exactly it is supposed to be, as an entity or medium (besides emptiness) is still hotly debated. I've read a lot of well credentialed sources questioning the nature of space, time, and spacetime, and do not accept the matter-of-fact statement, "space is expanding" as if emptiness could have the properties of a malleable medium. Owl

Great topic. We must distinguish between space and all the cosmic "stuff" in space. Who can imagine an end to space? What kind of boundary would that be, and, of course, what would be beyond that boundary but... more space... ad infinitum. We are limited in how far we can see, of course. It's called the cosmic event horizon, so what is beyond this limit, no one knows or can know. Mr Skeptic says that the cosmos is around 15 billion years old, i.e., from the big bang, based on the best information we have. But this "matter of factly" dismisses the possibility of an oscillating or "bang/crunch" cosmos as perpetually cycling. The primary argument against it is the "missing matter argument," i.e., that there is not enough matter out there to gravitationally "net" it all and bring it all back to eventually "crunch" or "bounce" and start another bang cycle. But science is finding more matter all the time... not only the mysterious "dark matter" but lots of ordinary matter like dust, rocks, gas clouds, planets, and black holes, from relatively small to supermassive. The "not enough matter" pronouncement is definitely premature. As for the matter-of-fact statement that "space is expanding," this assumes space as an entity rather than the emptiness in which entities of all kinds exist and expand out from the bang. I agree with Dragonstar in this respect, questioning, "so is space really expanding or are the things in it moving away from each other in an already infinite space?" The ontology of space, time and "spacetime" is not a settled debate, and I question their status as existing entities. So does the International Society for the Advanced Study of Spacetime, which sponsers conferences on the Ontology of Spacetime. (See Dennis Deiks' volumes of papers from those conferences.) Gotta go, but I look forward to further duscussion of these questions here. Owl

Hi folks, I'll jump in here on the side of time being just the convention of acknowledging event duration, i.e., between to clicks of a metaphorical stopwatch, "elapsed time" between two instants of now. Of course it has taken on a meaning beyond that in science, particularly in relativity in which it has become an entity of some sort which "dilates" etc. No doubt clocks keep time differently in different inertial frames of reference, but that doesn't mean they are measureing some "thing... time" which speeds up and slows down in different inertial environments. Time travel is, of course a science fiction devise. Now is the ongoing present. Past is no longer present or accessible but in memory and history, and future is not yet present, though we can "visit it" in imagination or probability studies... One not still happening, the latter not yet happening. Pretty simple really until it is reified into some kind of matrix/entity. Naturally "it takes time" for things to move, light to travel through space bearing images and information to observers. But don't let the language create something out of nothing. Now is all there is! Well, now I've dipped my toe into the water. I'll soon see if I want to wade in and swim or not. ( I kind of prefer a good dust bath as I ruffle my feathers!) Owl

Hi all, "Owl" here... a newbie but an old fart (65) and an amateur scientist (a retired psychologist and philosopher) with an avid interest in the ongoing science/philosophy discussion around the ontology of spacetime. I've read a ream of stuff on it and just finished an essay about it which I hope to put on a blog here as soon as I meet the time/posts requirements. Meanwhile, I"ll be reading related posts and pitching in when so moved. Thanks to the admin. for helping me register. I am not only old and forgetfull but quite lame re this new-fangled technology. Owl