... there was nothing, because there is no beginning.
As one of my favorite authors, Terry Pratchett, has written, stories don't start - they weave. What seems like a beginning is just the continuation of something else. Tom Stoppard once wrote, "We do on stage what most people do off, which is a kind of integrity if you look at every exit as an entrance somewhere else."
And there's the rub (to quote another bard): nothing is ever truly first. There's always something that came before. Even all the way back to that seminal event (that may or may not have occurred) called the Big Bang, and even prior to that - because for the singularity to "expand", it had to exist first, which means something was there before the Big Bang.
This is the trap of thinking in four dimensions - of thinking in terms of "time". Time, you see, isn't a location, it's a direction. It's flow - as in, time *is* flow and nothing else. We have no method to describe it that isn't self-referential. We have no tools for measuring it directly. And yet we observe its assumed effects.
We could argue that time is part of the universe we know, and that therefore time itself came into existence as part of the big bang. However, that solves nothing; it just complicates matter. For something to "pre-exist time" implies the existence of some kind of "supertime" (the same way that stating something as "outside our universe" implies something larger): it doesn't solve the problem, it merely shifts it up a level.
Furthermore, because of how time is - flow - once it existed it had always existed. Wrap your mind around that one for a few seconds: if time itself comes into existence, then any notion of "past" had to come into existence also, so "as soon as" time existed, there were past, present, and future already formed. Once time was around, it had to have always been around, because "always" is a concept of time.
Anything that happens "outside" time - without a time dimension - would, by definition, happen simultaneously/constantly/forever (there really isn't a non-temporal word that works). That means that what existed "before" the big bang would have to co-exist with whatever exists "after" the "universe" created by the big bang finishes/collapses/ends/whatever. In essence, not only is the big bang still happening in the "superuniverse", but it's also already over.
And yet, we see the stories weave as we always have, one second before the next. And just as no story every really begins, no story ever really ends - it just becomes part of another story, another path to weave.
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3 comments:
Hi there, Austin
I've had this post in the back of my mind for a couple of years now, and I've finally made a connection that has spurred me to comment on it.
You might know of Ethan Siegel - he's a cosmologist who writes a blog, Starts With A Bang, to address mostly scientific issues from pure cosmology to climate change. Back in October, he posted on the subject of What Happened Before The Big Bang?, which seems highly relevant to your post.
If I've understood the science correctly, from the current state of the universe (e.g. fluctations in the cosmic microwave background), we can deduce a history of the universe back to a point corresponding "to energies between 10^16 and 10^17 GeV" (I assume this is an average particle energy, which implies a temperature and a scale relative to the present universe). At that point a process called "inflation" ended; I don't think we understand what it was, but it produced the geometry and curvature of spacetime that we now observe, and it also had the effect of erasing any previous history of the universe.
So, to turn back to your post: from our present position, we can see things that are close enough for their light to reach us within the (post-inflation) lifetime of the universe, and we can deduce a history back to the immediately post-inflation instant. Beyond these points, we cannot go, either by observation or deduction. So I don't think there is any justification in talking of an "outside" or a "before". We may have an "inside" and an "after", but just because our language and "common sense" allow for the converses, it doesn't mean they exist.
Take care
Mark
Mark -
Well, part of the problem is that the date we can go back to is pretty much an event horizon: we can't view anything prior to it, or even know if there was anything prior to it. We're in a house with no windows or doors, and while we can see the walls, we can't see what may or may not lay beyond them.
What Siegel is doing is offering an analysis relative to time - and that's exactly the crux.
What happens to Siegel's "inflation curve" (the yellow line) if time isn't constant but, instead, itself gets created as part of the big bang? Well, the line ends up looking just like the other two (at least in some models).
Thinking about this gets tricky. If you have experience with relativity, that comes in handy.
If time gets created as part of the universe, then it's reasonable that, like everything else, it's "bunched up" or "denser" when it first emerges and then gradually spreads out as the expansion happens (some argue, in fact, that the expansion is time, but we'll leave that for later). That would create an identical exponential curve as we see for the other models in "hyper-time", though to "real time", it would look like the even slope of the yellow line (because the measuring tool itself is being affected, just like in relativity).
We know that time is plastic at high speeds if nowhere else. Assuming it has been linear for all of creation is taking a pretty big leap of faith, but it's also necessary, it at least some degree, since we rely on time for so many measurements. It's the classic error of assuming an "ought" from an "is": just because things are doesn't mean that they have always been or that they always will be.
Anyway, it's all a conjecture, but it's still fun to think about :)
Hi there, Austin
First, some background: my experience with relativity, so you'll have some context for the rest of what I say.
A reasonably thorough course on special relativity was included in the first year of my undergraduate degree (27 years ago!). As I recall it was 1/20 of the total taught content that year, so 12 hours of lectures, 4 hours of tutorials, and quite a few more hours working on example questions in preparation for those tutorials. I've been familiar with the basic ideas from SF and popular science for quite a lot longer, and I've tried to maintain that knowledge, even if I can't readily remember the exact formulae and methods these days.
It's definitely fun to think about this stuff, especially as I get to do so rather infrequently these days :-(
I think time is necessarily created with the Big Bang. More precisely, our first knowledge of Einsteinian spacetime is in the immediately post-inflation instant; time obviously existed then, and we have no knowledge that it did "before", so we might as well assume it was created then. I guess it's rather like absolute zero for temperature: the axis on the graph continues into negative numbers, but they're not physically meaningful.
"Time is plastic at high speeds": yes, in the sense that if two reference frames have a high relative speed, observers in each frame will see clocks in the other frame running slow relative to their own clocks. An assumption that time has always been linear is, I think, a reasonable application of Occam's razor (we have no evidence of any other behaviour), but I think it's also a consequence of our almost complete ignorance of the nature of time. Time seems to be such a fundamental part of the fabric of the universe that science does not seem to have any significant grasp on it. It is always the independent variable, progressing with utter inexorability at one second per second. In this sense, what would it mean for time to be "bunched up"? How could we perceive time passing at a rate of, say, two or three seconds per second? I assume this is what you're getting at with "real time" (for observers within the universe) vs. "hypertime" (for hypothetical observers "outside" the universe).
Apologies if this is a muddle; it's a difficult subject to think about clearly, and especially so when I'm tired. I think I had better stop now, while I can still push the Publish button!
Take care
Mark
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