The age of the universe - time before time

[normal]

I saw jamest's thread about the age of the universe, and it got me wondering. I'll begin by saying I don't know very much about what I'm going to ask, but here we go:

We have estimated, by various methods(?), that the universe is something like 13-14 billion years old(yes?). And at the beginning we think there was some sort of singularity which contained all of time and space (even matter?). At this "time", the singularity, which must have been highly unstable, expanded VERY rapidly, and it took millions of years before there was any space separating matter from matter (is this right?). So. At the beginning, when we had this singularity (I think I have heard it said or read somewhere that) the physical laws were bent or even broken. The conditions were supposedly so extreme as to make the laws we operate under today impossible.

Does anyone know anything about this? The broken laws?

And was there time at the point of the singularity - where we think the universe started?

If the conditions were so extreme right after the singularity - could it be that during the singularity, there was no time (which makes the word during useless)?

Or must there be time?

If there must be time (which seems intuitively correct to me), then was time bent and twisted during the singularity? Could it have lasted for longer than our calculated age of the universe? From my non-existant knowledge it could.

Anyone got anything resembling knowledge in this area?

[cowiz]

I saw jamest's thread about the age of the universe, and it got me wondering. I'll begin by saying I don't know very much about what I'm going to ask, but here we go:

We have estimated, by various methods(?), that the universe is something like 13-14 billion years old(yes?). And at the beginning we think there was some sort of singularity which contained all of time and space (even matter?). At this "time", the singularity, which must have been highly unstable, expanded VERY rapidly, and it took millions of years before there was any space separating matter from matter (is this right?). So. At the beginning, when we had this singularity (I think I have heard it said or read somewhere that) the physical laws were bent or even broken. The conditions were supposedly so extreme as to make the laws we operate under today impossible.

Does anyone know anything about this? The broken laws?

And was there time at the point of the singularity - where we think the universe started?

If the conditions were so extreme right after the singularity - could it be that during the singularity, there was no time (which makes the word during useless)?

Or must there be time?

If there must be time (which seems intuitively correct to me), then was time bent and twisted during the singularity? Could it have lasted for longer than our calculated age of the universe? From my non-existant knowledge it could.

Anyone got anything resembling knowledge in this area?

The laws were not broken - they operated differently. Your question is big because they are working on the Grand Unified Theory (GUT) that hopefully will answer your question.

[Nautilidae]

I saw jamest's thread about the age of the universe, and it got me wondering. I'll begin by saying I don't know very much about what I'm going to ask, but here we go:

We have estimated, by various methods(?), that the universe is something like 13-14 billion years old(yes?). And at the beginning we think there was some sort of singularity which contained all of time and space (even matter?). At this "time", the singularity, which must have been highly unstable, expanded VERY rapidly, and it took millions of years before there was any space separating matter from matter (is this right?). So. At the beginning, when we had this singularity (I think I have heard it said or read somewhere that) the physical laws were bent or even broken. The conditions were supposedly so extreme as to make the laws we operate under today impossible.

Does anyone know anything about this? The broken laws?

At the time of the singularity, the known physical laws break down. What this means is that the main frameworks that we have today, general relativity and quantum mechanics, begin to give nonsensical answers. This is because the singularity is a quantum object with great relativistic effects. Thus, to completely describe this singularity, one needs a framework in which general relativity and quantum mechanics are consistent with each other. This is a theory of quantum gravity.

And was there time at the point of the singularity - where we think the universe started?

Yes, there was time. However, events occurring before the Big Bang are not accessible to us, so it seems as if there was no time before the Big Bang.

If there must be time (which seems intuitively correct to me), then was time bent and twisted during the singularity? Could it have lasted for longer than our calculated age of the universe? From my non-existant knowledge it could.

When we define the age of the universe, we do not define the history of the singularity. We define the time between now and the moment of expansion.

[cogwheel]

Just to add another wording to the mix...

It's not so much that the singularity breaks the physical laws. It's really that the physical laws we humans have come up with to explain the things we're able to observe are insufficient to explain what was going on at the very earliest stages of the universe.

I may be confusing this with some other problem of physics, but I believe answering this question (or at least shedding some light on it) is one of the missions of the LHC.

[FBM]

It may be that time itself was created at the BB, in the sense that it may be a product of the decoupling of the physical forces. Interesting stuff, that, but seems that it may be forever beyond our capacity to know for sure.

Edit: For that matter, it's not even guranteed that time is anything outside our perception.

[Loki_999]

There are no broken laws. However, there may be laws that we don't fully understand yet (if we will ever!). We are limited by our 4 dimensional experienced lives and the bounds of our imagination.

Nature is nature, it does not have to conform to our understanding or expectations.

If we finally get to understand all the rules of the game, then maybe will will finally be able to understand why there is a universe in the first place. If you think about it, why the hell should anything at all exist?

[hackenslash]

A couple of points to be made, although most of the ground has already been covered above. Firstly, it is far from clear that there even was a singularity. Brane cosmology effectively removes it, although of course it is also far from clear that brane cosmology reflects reality at this point. Either way, the singularity has not been established.

Secondly, the idea that time began at the big bang is a difficult one. If there was a singularity, then it's fairly certain that the singularity itself did not experience time, but that doesn't mean that time did not exist. It's well-understood that time slows in the presence of mass, and given the mass of the singularity, time would almost certainly not have passed there. However; we are well aware of entities within the cosmos that do not experience the passage of time, but does that mean that time doesn't exist? Of course not.

Thirdly, time is real. We can't say a huge amount about its nature at the moment, but it is real in the very same sense that gravity is real, another thing about whose nature we can say very little. The model of time arising from GR seems of the most utility, since it connects the dots quite nicely and builds a picture that, while counter-intuitive in many respects, can be intuited from observations. The idea that time is a space-like dimension through which we are moving at light speed has much to offer, as it explains why time slows for a body in motion.

Finally, on the subject of the breach of physical laws, this is again something we can say little about, and this will continue to be the case until we have a workable quantum model of gravity. All we can really say is that there is a fuzzy area between quantum mechanics and general relativity that will need to be clarified in order to understand a quantum event with relativistic mass, if indeed the singularity turns out to be the correct picture of the instantiation of our local cosmic expansion. This is the sense in which our physical laws break down. Our understanding is necessarily hobbled by the fact that we're talking about an event that requires the application of both of our best theories at the same time, while not having any means of unifying those theories.

[Farsight]

I'll have a go at this one:

We have estimated, by various methods(?), that the universe is something like 13-14 billion years old(yes?).

Yes. When we work back it looks like the universe began 13.7 billion years ago.

And at the beginning we think there was some sort of singularity which contained all of time and space (even matter?).

Like hackenslash said, it wasn't necessarily a singularity. And whilst it contained all of space and energy, it didn't contain matter per se, and it isn't quite right to say it contained all of time, because time isn't on a par with space and energy. But hey, look at me nitpicking. Yes, what you said is more or less how it seems to be.

At this "time", the singularity, which must have been highly unstable, expanded VERY rapidly, and it took millions of years before there was any space separating matter from matter (is this right?).

Not quite, see http://en.wikipedia.org/wiki/Big_Bang#T ... e_Big_Bang for a fairly good article.

So. At the beginning, when we had this singularity (I think I have heard it said or read somewhere that) the physical laws were bent or even broken. The conditions were supposedly so extreme as to make the laws we operate under today impossible. Does anyone know anything about this? The broken laws?

The laws of physics don't actually exist. You can't look up to the sky and point them out. All they really are is a set of apparent rules drawn from observations and mathematics. And nowadays people say that they're derived from symmetries. See http://en.wikipedia.org/wiki/Physical_l ... symmetries and http://en.wikipedia.org/wiki/Symmetry_(physics). But I suppose it's reasonable to say that a symmetry was broken.

And was there time at the point of the singularity - where we think the universe started?

No.

If there must be time (which seems intuitively correct to me), then was time bent and twisted during the singularity? Could it have lasted for longer than our calculated age of the universe? From my non-existant knowledge it could.

No.

Anyone got anything resembling knowledge in this area?

Yes and no. I don't know how the universe began. I don't even know if the big bang was the beginning of everything. For all I know the universe we can see might be a subset of a bigger universe. But I do know about time.