Is the big bang really the beginning of time?

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Is the big bang really the beginning of time?

Postby ianfort » Tue Aug 09, 2011 5:58 pm UTC

I was watching an interview with Stephen Hawking recently. He said that saying there was time before the big bang was like searching for a point south of the south pole.

Now, I know he's pretty much a genius and can probably give an excellent argument for such an idea, but the interviewer didn't press him on it, and they moved on to different things. What I'd like to know is what evidence we have for the big bang being the true beginning of time, because I know that we once thought there was nothing beyond our galaxy. All throughout history, we've been saying "Because we don't know of anything beyond this, there's nothing beyond this," And some very intelligent people have been among them. But it just seems to go against the Copernican principle.

If you can show me a good amount of scientific evidence for the big bang being the absolute beginning of time, I will likely concede, but until then, I'm all for the infinite multiverse.

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Re: Is the big bang really the beginning of time?

Postby broken_escalator » Tue Aug 09, 2011 6:01 pm UTC

It's turtles all the way down.

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Re: Is the big bang really the beginning of time?

Postby ianfort » Tue Aug 09, 2011 6:03 pm UTC

What the hell does that mean?

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Re: Is the big bang really the beginning of time?

Postby broken_escalator » Tue Aug 09, 2011 6:05 pm UTC


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Re: Is the big bang really the beginning of time?

Postby Dopefish » Tue Aug 09, 2011 6:06 pm UTC

Define time.

I'm not convinced the notion has meaning prior to the big bang.

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Re: Is the big bang really the beginning of time?

Postby Ulc » Tue Aug 09, 2011 6:11 pm UTC

It's a reference to the idea that the earth is flat and resting on the back of a large turtle, where it's asked what's keeping the turtle up, and the answer is that it's turtles all the way down. Which is clearly a nonsense answer if there is nothing *but* turtles, there's no "all the way down".

Or to put it in another way, your question do not make sense. Or even better, your question doesn't make sense, because you're trying to enforce terms from our universe, on a theoretical 'nother universe. Time is defined as something that happens in our universe, so even if something existed before big bang*, it wouldn't have time.

Or as Hawking phrases it, it's like asking what's south of the south pole, when per definition the south pole is the south-most point.


*We have no particular reason to think so though, except the fact that our human brains have a hard time dealing with "Nothing exploded, and then thing was"
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Re: Is the big bang really the beginning of time?

Postby joeframbach » Tue Aug 09, 2011 6:12 pm UTC

I am not a physicist, but here's my initial thoughts on the matter.

As an object approaches the speed of light, time slows down from its reference frame. This occurs for objects nearing a singularity/black hole. The "big bang" is just that, a singularity representing all the matter in existence. The only reference frame is that of the singularity. There is no time difference, as there is no other reference frame from which to measure time.

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Re: Is the big bang really the beginning of time?

Postby ianfort » Tue Aug 09, 2011 6:16 pm UTC

So will there be an end of time?

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Re: Is the big bang really the beginning of time?

Postby Ulc » Tue Aug 09, 2011 6:21 pm UTC

ianfort wrote:So will there be an end of time?


We can say for certain that we haven't observed one such yet.

Whether one will happen? That depends on the ultimate fate of the universe, which is a argument that you don't want to observe astrophysicists having*. It tends to involve unpleasantness and them throwing glasses of wine into each others face.

Not a pretty sight.

*http://en.wikipedia.org/wiki/Ultimate_fate_of_the_universe
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Re: Is the big bang really the beginning of time?

Postby ianfort » Tue Aug 09, 2011 9:40 pm UTC

If instead of all universes being born of another universe, all universes arise spontaneously due to quantum fluctuations, I think the turtle problem can be averted since few or none of the universes are causally connected. You can have an infinite multiverse with infinite time and not have to deal with an infinite regress.

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Re: Is the big bang really the beginning of time?

Postby Yakk » Tue Aug 09, 2011 9:59 pm UTC

It is true we don't know: but to be honest, we don't know a lot that we "know".

At the same time, we have pretty good models which do say that "before the big bang" is similar to "south of the south pole".

We don't know that there isn't an invisible pink unicorn over your shoulder (it is undetectable by any means), but we have models that don't require that invisible pink unicorn, and we don't have any models that are more useful or predictive that do require that invisible pink unicorn.

There isn't, as far as I know, a cosmological model with significantly greater predictive power that requires "time before the big bang" to be a sentence that makes sense. So while there are theoretical models that involve branes colliding, use exotic meanings of the word time, use black holes to seed universes, have quantum flux in a dead universe create new ones with inflation, etc -- these are all just (really complex and interesting) theoretical models.

Now, prior to noticing other extra-galactic objects, it is true that models didn't require them either. And our models aren't perfect right now (even if they are much better than the models around when we had but a single galaxy to observe). So there could turn out to be "time before the big bang" -- but we don't have any (good) reason (other than we think it is icky for there not to be) for that to be the case. And physicists are cautious about making claims based on icky.
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Re: Is the big bang really the beginning of time?

Postby ianfort » Tue Aug 09, 2011 10:41 pm UTC

Yakk wrote:It is true we don't know: but to be honest, we don't know a lot that we "know".

At the same time, we have pretty good models which do say that "before the big bang" is similar to "south of the south pole".

We don't know that there isn't an invisible pink unicorn over your shoulder (it is undetectable by any means), but we have models that don't require that invisible pink unicorn, and we don't have any models that are more useful or predictive that do require that invisible pink unicorn.

There isn't, as far as I know, a cosmological model with significantly greater predictive power that requires "time before the big bang" to be a sentence that makes sense. So while there are theoretical models that involve branes colliding, use exotic meanings of the word time, use black holes to seed universes, have quantum flux in a dead universe create new ones with inflation, etc -- these are all just (really complex and interesting) theoretical models.

Now, prior to noticing other extra-galactic objects, it is true that models didn't require them either. And our models aren't perfect right now (even if they are much better than the models around when we had but a single galaxy to observe). So there could turn out to be "time before the big bang" -- but we don't have any (good) reason (other than we think it is icky for there not to be) for that to be the case. And physicists are cautious about making claims based on icky.


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Re: Is the big bang really the beginning of time?

Postby idobox » Wed Aug 10, 2011 1:27 am UTC

Another way of thinking the problem: if nothing exists before the big-bang, there can be no events. How do you define time in those conditions? Or distance, by the way, or mass, or wathever?
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Re: Is the big bang really the beginning of time?

Postby Interactive Civilian » Wed Aug 10, 2011 3:38 am UTC

Space and time are interconnected as Space-time, according to relativity. If that is correct, then, as it was the beginning of space, yes, the Big Bang was the beginning of time. Trying to have time before the big bang is like trying to have space with a volume less than zero.

At least, that is my understanding.
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Re: Is the big bang really the beginning of time?

Postby thoughtfully » Wed Aug 10, 2011 3:48 am UTC

Another way to see it: If spacetime is quantized, then around scales of the Planck Length, it becomes a foamy, roiling, fuzzy mess. When the size of the Universe is of this scale, measurements of distance and time are meaningless. Time begins when this epoch is left behind and spacetime as we know it emerges. This is also when Gravity splits off from the other forces, not so incidentally.
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Re: Is the big bang really the beginning of time?

Postby Technical Ben » Wed Aug 10, 2011 6:34 am UTC

Dopefish wrote:Define time.

I'm not convinced the notion has meaning prior to the big bang.


It can have two meanings or descriptions that I know of. You have space/time. In which case, you would need to prove spacetime, space or time existed before the big bang. Well, that leads me on to the second description. It can be two points of measurement that are recorded. As every measurement we do will be separated by time or space from the next measurement. To prove time existed before the big bang, we only need two measurements (or theories showing there are more then 2 states at separate points) from before the big bang to show time existed.

However, if we cheat, and define "the big bang" as the "first action" of the universe, there is no "before". So with no measurement or state before, we cannot have a second measurement to plot a graph of time onto. A bit like the "speed of light" is the "maximum" speed. If we make further discoveries, we "cheat" and change the speed to match that new discovery. So in a definition sense, we never find anything before the big bang. But in a physics, mathematics or future discoveries, we may find something happened before that, but then just rename that thing the big bang. :)

Unless we find out that the universe has existed forever. It's a rather difficult concept, but we would only need the physics and mathematical equations to back it up.
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Re: Is the big bang really the beginning of time?

Postby idobox » Wed Aug 10, 2011 9:00 am UTC

Technical Ben wrote:Unless we find out that the universe has existed forever. It's a rather difficult concept, but we would only need the physics and mathematical equations to back it up.

The universe appearing out of nowhere is a pretty difficult concept too. Philosophers have been considering the two options since at least acient Greece, with no clear winner.
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Re: Is the big bang really the beginning of time?

Postby Tass » Wed Aug 10, 2011 10:51 am UTC

idobox wrote:
Technical Ben wrote:Unless we find out that the universe has existed forever. It's a rather difficult concept, but we would only need the physics and mathematical equations to back it up.

The universe appearing out of nowhere is a pretty difficult concept too. Philosophers have been considering the two options since at least acient Greece, with no clear winner.


I'd argue that the two concepts are pretty much the same, given that time is a property of the universe, and that it is not absolute. Time is just another property following the mathematical system that is the universe, does it matter whether there is a finite or an infinite amount of it?

Define a different-second as being shorter the closer to the big bang: voila, now the universe has always existed in different-time. In some way it even makes more sense as you avoid the ridiculously small timescales involved in the early eras. Now the inflationary epoch might be for example from -36ds to -32ds, and quark epoch from -12ds to -6ds. You might even define it in such a way that the ultimate heat death and infinite size lies a finite time in the future - now the universe has an end but no beginning. Reverse the arrow of time and you have a shrinking universe, created at infinite size that are going to keep shrinking forever. The question that does not make sense is now "what came before the time when the universe was infinite?".

It is not inherently more wrong to do it this way than the way time is usually defined. Sure some physical constants will be changing, but the unitless ones still don't, and other "constants" which are changing now, might not under the new system, for example the size of the universe might be made constant.

The question to ask is not "how was the universe created", but rather "why is the universe".

No one asks "what will come after the universe reaches infinite size?" yet that question makes as much sense as the often stated "what came before the big bang".

Well unless the universe is actually cyclical with no big bang singularity because of quantum gravity. Like if our planet was connected with an oh so small strip of matter from the south pole to another planet, then you could keep wandering south along it. But in this case there would actually be no south pole, and the question is still senseless. In the same way I understand the question "what came before the big bang", as "what came before the big bang singularity". Presupposing the singularity means the question makes no sense, just as assuming the existence of the south pole means there are no further south. If "big bang" is just nucleosynthesis and all that jazz, then there may well be a before.

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Re: Is the big bang really the beginning of time?

Postby shane-m-pelletier » Wed Aug 10, 2011 1:40 pm UTC

You may be interested in the first episode of "Curiosity" which is hosted by Stephen Hawking. It examines the question of whether or not the universe needed a creator. It explains a lot of things through simple examples.

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Re: Is the big bang really the beginning of time?

Postby gavin » Wed Aug 10, 2011 3:21 pm UTC

I generally view time as a sequence of events laid one on top of the other in much the same way video is strung together. I use this understand to cope with the fact that time as understand it in units of measure is relative to location and the speed of the object measuring time. If there were any events before the big bang (such as another universe collapsing to form the point of significant mass/energy needed for the bang) then with my understanding of time it would exist. But seconds, minutes, hours? It's all far too relative to have existed in any meaningful way before the formation of our universe. The big bang was the start of things as we know it. I'm not so sure that time exists now as we actually understand it. One second to us now may not have been the same as one second a decade ago (or perhaps a second ago) just as an astronaut traveling away from Earth experiences a different amount of time that we do here on earth.

The assumption that the big bang is the beginning of time hinges on the idea that it is the first event. Anything proceeding before the big bang would be, logically, before it and therefore sequentially earlier. Such an expression would necessitate time in some way. That being said, there would still need to be an initial time at some point. A lowest turtle, if you will.

shane-m-pelletier wrote:You may be interested in the first episode of "Curiosity" which is hosted by Stephen Hawking. It examines the question of whether or not the universe needed a creator. It explains a lot of things through simple examples.
I found it well thought out but not really a good response to the question of whether or not the universe needed a creator (where creator is a "cause", in my mind, even if the cause is a creator of some sort). It seems like the answer is always "we don't really know". Unless you feel I misunderstood or missed some compenent to his discussion.

The universe appearing suddenly has more weight than "Turtles all the way down". Especially when considering scientific laws and principles we already have (such as thermodynamics/entropy and the principle of causality).

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Re: Is the big bang really the beginning of time?

Postby Technical Ben » Wed Aug 10, 2011 4:26 pm UTC

idobox wrote:
Technical Ben wrote:Unless we find out that the universe has existed forever. It's a rather difficult concept, but we would only need the physics and mathematical equations to back it up.

The universe appearing out of nowhere is a pretty difficult concept too. Philosophers have been considering the two options since at least acient Greece, with no clear winner.

Well, yes, but that was not my point entirely. More that we can be forced to accept (even if we don't understand) that the universe is either without a beginning or with a beginning, but currently the evidence supports the theory that it had a beginning. This causes more problems than if the evidence supported the universe not having a beginning. Without a beginning, we just have a circular or infinite system to comprehend. Easy to comprehend to make mathematical models of. But to mathematically create something from nothing is rather difficult. How can you "+1" to the energy of space-time without any energy to add to it?
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Re: Is the big bang really the beginning of time?

Postby ianfort » Wed Aug 10, 2011 5:37 pm UTC

One thing that confuses me is that there is currently evidence from the cosmic background radiation that suggests that the universe is almost completely flat. But the only way the universe could have finite space is if it has a closed curvature (unless space has some clearly-defined edge, but that raises more questions than answers). So would that suggest that space is infinite? That's an absurdity if all space was created in the big bang, for it goes from finite to infinite in a finite amount of time. Unless space did exist before the big bang, and the spacial expansion brought about by dark energy is only adding to the already infinite amount. And doesn't the fact that space can curve at all imply a 4-or-more-dimensional spacial medium it's curving through?

I am not terribly learned in this field, so please forgive me for any inaccuracies.

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Re: Is the big bang really the beginning of time?

Postby gavin » Wed Aug 10, 2011 7:25 pm UTC

ianfort wrote:One thing that confuses me is that there is currently evidence from the cosmic background radiation that suggests that the universe is almost completely flat. But the only way the universe could have finite space is if it has a closed curvature (unless space has some clearly-defined edge, but that raises more questions than answers). So would that suggest that space is infinite? That's an absurdity if all space was created in the big bang, for it goes from finite to infinite in a finite amount of time. Unless space did exist before the big bang, and the spacial expansion brought about by dark energy is only adding to the already infinite amount. And doesn't the fact that space can curve at all imply a 4-or-more-dimensional spacial medium it's curving through?

I am not terribly learned in this field, so please forgive me for any inaccuracies.
What if that empty space has always existed or existed before the big bang? If that's possible, then, let's treat the initial point at which the big bang as though it were just a celestial body like an incredibly dense star floating around in space and not a unique occurance. This "star" has consumed all significant volumns of matter and energy in the area. Perhaps there are many such masses that are exploding all throughout space creating "universes" in their own little areas but on the same plane of existence. Maybe as two or more universes begin to collide, enough matter/energy combines to create yet another mass to create another "universe"? I use universes in this example as the product of one big bang rather than the entirety of existence as we know it. Universes seperated by distance, not dimension or something of that nature. But do not forget that this one single bang does not necessarily have to constitute the start of everything in this plane of existence. The explosion would then change time and space as we know it due to the energy involved but not necessarily cause "space" to exist. Is there evidence to disprove such a possibility?

I am unsure how to address the flat nature of the universe, though. I have been confused by that for some time now.

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Re: Is the big bang really the beginning of time?

Postby thoughtfully » Wed Aug 10, 2011 8:07 pm UTC

The usual explanation for the flatness is from inflation. It appears flat for the same reason that the surface of the Earth appears flat; inflation blew up the Universe so much that the observable part from where we are is only a small portion of any possible larger curvature.
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Re: Is the big bang really the beginning of time?

Postby gavin » Wed Aug 10, 2011 8:11 pm UTC

thoughtfully wrote:The usual explanation for the flatness is from inflation. It appears flat for the same reason that the surface of the Earth appears flat; inflation blew up the Universe so much that the observable part from where we are is only a small portion of any possible larger curvature.
I guess any explosion in a vacuum would be essentially an ever expanding sphere (diminishing in density). So I understand why it may appear to "look" like the surface of the earth (an oblate spheroid) physically, but what impact does this have on background radiation?

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Re: Is the big bang really the beginning of time?

Postby Sizik » Thu Aug 11, 2011 1:22 am UTC

How do we know the universe is spherical and not toroidal?
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King Author wrote:If space (rather, distance) is an illusion, it'd be possible for one meta-me to experience both body's sensory inputs.
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Re: Is the big bang really the beginning of time?

Postby ianfort » Thu Aug 11, 2011 4:21 am UTC

No, I've read about studies of the cosmic microwave background radiation that either confirmed or provided strong evidence for a mostly flat universe. Perhaps these studies are not as legitimate as I initially thought them to be?

Edit: Nevermind about it not being legit. It's on NASA's page: http://map.gsfc.nasa.gov/universe/uni_shape.html

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Re: Is the big bang really the beginning of time?

Postby gavin » Thu Aug 11, 2011 2:52 pm UTC

ianfort wrote:No, I've read about studies of the cosmic microwave background radiation that either confirmed or provided strong evidence for a mostly flat universe. Perhaps these studies are not as legitimate as I initially thought them to be?

Edit: Nevermind about it not being legit. It's on NASA's page: http://map.gsfc.nasa.gov/universe/uni_shape.html
Very interesting, thanks for the link. When I was on my way home last night I also realized that the earth example given doesn't make since due to the fact that we're not on "top" of the universe like we are on the Earth. We would then still be able to observe a curve wherever the nearest "top" was.

What did you think though, about my example of space not necessarily being created by the big bang? Is there a reason why this cannot be so? Did that provide a plausible response to your question on that?

The flat shape continues to remain a mystery to me though.

Half joke\half serious: I think it'd be hilarious if we discovered that we were a complex computer program and that's why the universe is flat. We are racing towards creating universes all the time, video games are an example of a very limited universe with limited laws and physics that we design. The more indepth and intricate they become, the closer to creating something of a universal scale gets. It'd be funny if a previous universe already thought of that and we're it.

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Re: Is the big bang really the beginning of time?

Postby Tass » Thu Aug 11, 2011 3:05 pm UTC

ianfort wrote:That's an absurdity if all space was created in the big bang, for it goes from finite to infinite in a finite amount of time.


No. If space is infinite then it has always been infinite. All the way back to the singularity.

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Re: Is the big bang really the beginning of time?

Postby gavin » Thu Aug 11, 2011 3:24 pm UTC

Tass wrote:No. If space is infinite then it has always been infinite. All the way back to the singularity.
This sounds logical. Though few things actually point to anything really being infinite. Even if unimagineably massive I do not think it'd be infinite. I still don't tie the existence of space to the big bang though. Unless someone presents evidence to the contrary.

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Re: Is the big bang really the beginning of time?

Postby Tass » Thu Aug 11, 2011 3:31 pm UTC

gavin wrote:I still don't tie the existence of space to the big bang though.


I don't know what you mean by that. The big bang is just the boundary condition in one end of the universe. In the time dimension.

How is it in any way special in relation to the other boundary conditions ("closed hypersphere"/"infinite" and "infinitely big and empty an infinite time away"/"big crunch").

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Re: Is the big bang really the beginning of time?

Postby gavin » Thu Aug 11, 2011 3:38 pm UTC

Tass wrote:
gavin wrote:I still don't tie the existence of space to the big bang though.


I don't know what you mean by that. The big bang is just the boundary condition in one end of the universe. In the time dimension.

How is it in any way special in relation to the other boundary conditions ("closed hypersphere"/"infinite" and "infinitely big and empty an infinite time away"/"big crunch").
What I mean is that I think the singularity may be able to be viewed in the same way as a star existing in space. That space already existed before the bang occured. Perhaps there were many other "singularities" throughout this plane of existence. Maybe a significant scoping out would see multiple such universes (clusters of galaxies and other matter expanding away from an initial singularity)? Perhaps these universes eventually collide and combine to form new singularities? Would this theory (which I'm sure already exists and has a name) do anything to discount evidence we already have?

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Re: Is the big bang really the beginning of time?

Postby Tass » Thu Aug 11, 2011 4:41 pm UTC

gavin wrote:What I mean is that I think the singularity may be able to be viewed in the same way as a star existing in space. That space already existed before the bang occured.


If there are more dimensions, maybe. It might not be a singularity in the other dimensions. Or if quantum gravity means it is not a singularity at all, then there could be a before, as already said multiple times.

gavin wrote:Maybe a significant scoping out would see multiple such universes (clusters of galaxies and other matter expanding away from an initial singularity)? Perhaps these universes eventually collide and combine to form new singularities? Would this theory (which I'm sure already exists and has a name) do anything to discount evidence we already have?


You are talking about explosions in space that are already there, rather than a singularity encompassing all space. Yes that would be very different and is discounted by evidence.

The closest we get is some flavors of brane theory, in which there are more dimensions and multiple big bangs might be happening all around.

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Re: Is the big bang really the beginning of time?

Postby gavin » Thu Aug 11, 2011 4:48 pm UTC

Tass wrote:If there are more dimensions, maybe. It might not be a singularity in the other dimensions. Or if quantum gravity means it is not a singularity at all, then there could be a before, as already said multiple times.

You are talking about explosions in space that are already there, rather than a singularity encompassing all space. Yes that would be very different and is discounted by evidence.

The closest we get is some flavors of brane theory, in which there are more dimensions and multiple big bangs might be happening all around.
Ah, then elaborate, please. If you are willing.

1. Why does the big bang have to be the point of inception of space itself?
2. Why can't multiple big bangs have occured and be occuring but too far away to recieve measurements from?

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Re: Is the big bang really the beginning of time?

Postby Ibid » Thu Aug 11, 2011 11:16 pm UTC

gavin wrote:
Tass wrote:If there are more dimensions, maybe. It might not be a singularity in the other dimensions. Or if quantum gravity means it is not a singularity at all, then there could be a before, as already said multiple times.

You are talking about explosions in space that are already there, rather than a singularity encompassing all space. Yes that would be very different and is discounted by evidence.

The closest we get is some flavors of brane theory, in which there are more dimensions and multiple big bangs might be happening all around.
Ah, then elaborate, please. If you are willing.

1. Why does the big bang have to be the point of inception of space itself?
2. Why can't multiple big bangs have occured and be occuring but too far away to recieve measurements from?


1. The reason is that the matter in the universe is not flying away from a central point, each point is expanding away from the others. The common analogy is that if space were two dimensional, it'd be an infinite rubber sheet. The various palces are points on the sheet, and the sheet is expanding. There is no "centre" to expand from, just a bunch of points expanding. (For a more finite space/time, wrap the sheet into a sphere like a balloon and expand it. But don't think he thrid dimension as being part of space-time in that analogy).

The proof of this is that IF it was an explosion in space we'd be able to see where we were rushing away from (distribution of matter would be different, cosmic background radiaion wouldn't be the same brightness in all directions, a couple more estoric ones). We don't see any of that, ergo there is no centre of expansion, ergo it is not an explosion in space.

From that we then say "okay so the galazies moving away from us is space moving away from us, so that means that when all the galaxies were in the same place, all of space was in the same place". And that results in a singularity at the big bang.

2. Simply put, there's nowhere for them to be taking place IN. If the big bang created space, then where the hell can these "other" big bangs be occuring? There's noplace for them to be! Some types of Brane theory do allow other locations for them to occur, but for vanilla, proven, physics what you see is what you get.
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Re: Is the big bang really the beginning of time?

Postby gavin » Fri Aug 12, 2011 1:18 pm UTC

Ibid wrote:1. The reason is that the matter in the universe is not flying away from a central point, each point is expanding away from the others. The common analogy is that if space were two dimensional, it'd be an infinite rubber sheet. The various palces are points on the sheet, and the sheet is expanding. There is no "centre" to expand from, just a bunch of points expanding. (For a more finite space/time, wrap the sheet into a sphere like a balloon and expand it. But don't think he thrid dimension as being part of space-time in that analogy).

The proof of this is that IF it was an explosion in space we'd be able to see where we were rushing away from (distribution of matter would be different, cosmic background radiaion wouldn't be the same brightness in all directions, a couple more estoric ones). We don't see any of that, ergo there is no centre of expansion, ergo it is not an explosion in space.

From that we then say "okay so the galazies moving away from us is space moving away from us, so that means that when all the galaxies were in the same place, all of space was in the same place". And that results in a singularity at the big bang.
We don't see or observe locations where there is no empty space. What we're seeing is the expansion of matter and energy into the vacuum. There is no reason either why the big bang had to occur in any center of the universe nor is there any reason why the nature of the vacuum that is space doesn't have its own unique principles and perhaps it even had some "stuff" which didn't originate where most of our universe did. Additionally, several of my physics books seemed pretty adament that the gravity, force, and momentums involved in the big bang were of such a magnitude that the physics that apply now, right here, may have been changing randomly at the beginning.

Perhaps you can explain it in a different way than a rubber sheet (didn't have a bed wetting problem so we never owned one)?

2. Simply put, there's nowhere for them to be taking place IN. If the big bang created space, then where the hell can these "other" big bangs be occuring? There's noplace for them to be! Some types of Brane theory do allow other locations for them to occur, but for vanilla, proven, physics what you see is what you get.
I'm primarily focused on why space (the vacuum) was created by the bang.

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Re: Is the big bang really the beginning of time?

Postby Tass » Sat Aug 13, 2011 9:04 pm UTC

gavin wrote:There is no reason either why the big bang had to occur in any center of the universe


What do you mean by "center"?

gavin wrote:nor is there any reason why the nature of the vacuum that is space doesn't have its own unique principles and perhaps it even had some "stuff" which didn't originate where most of our universe did


What do you mean by "where"?

gavin wrote:Additionally, several of my physics books seemed pretty adament that the gravity, force, and momentums involved in the big bang were of such a magnitude that the physics that apply now, right here, may have been changing randomly at the beginning.


What they meant was that close enough to the big bang we can no longer use the theory of general relativity, because the curvature is too large, but have to use a theory of quantum gravity. General relativity predicts a singularity, we do not yet have a working quantum gravity theory, therefore we cannot know for sure whether the singularity was there.

Oh and by the way:
gavin wrote:...the vacuum that is space doesn't have its own unique principles...


It does. And it is exactly these principles that general relativity is concerned with. (Well except it may do new weird things when the curvature is large).

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Re: Is the big bang really the beginning of time?

Postby rattusprat » Mon Aug 15, 2011 10:25 am UTC

gavin wrote:Half joke\half serious: I think it'd be hilarious if we discovered that we were a complex computer program and that's why the universe is flat. We are racing towards creating universes all the time, video games are an example of a very limited universe with limited laws and physics that we design. The more indepth and intricate they become, the closer to creating something of a universal scale gets. It'd be funny if a previous universe already thought of that and we're it.


But then who or what created the video game?
Must have been one of those pesky turtles.

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Re: Is the big bang really the beginning of time?

Postby gavin » Mon Aug 15, 2011 2:20 pm UTC

So, with regards to my question on why the vacuum (empty/relatively empty space) had to be created by an explosion of mass and energy?

rattusprat wrote:But then who or what created the video game?
Must have been one of those pesky turtles.
All the way down to the turtle whose universe isn't flat?


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