what was there before Big Bang?

[nernico]

What created Big Bang? What created the thing that created Big Bang? And why is there something rather than nothing?

[Fuzzwood]

Why do you assume it was created?

[pwagen]

 

 

And why is there something rather than nothing?

 

Why suppose there should be nothing rather than something?

 

http://plato.stanford.edu/entries/nothingness/#WhyTheSomRatThaNot

[ajb]

What created Big Bang? What created the thing that created Big Bang? And why is there something rather than nothing?

 

All good questions right at the forefront of modern cosmology and philosophy.

 

String cosmology may provide us with a notion of before the big bang, but this is all really very speculative. Veneziano I believe was the first to realise that inflationary models can be obtained from string theory [2]. I don't really know much about string and brane cosmology, I am sure you can find good reviews on the arXiv.

 

Loop quantum gravity is another approach to quantum gravity and this suggests that the Universe has a finite size at the start of the "big bang" and was not a point-like singularity. This suggest the scenario of a big bounce. Bojowald [1] I believe was the first to apply loop quantum gravity to the very early Universe. Again this is not something I know much about.

 

In short, people do talk about physics before the big bang. However I think it is all very speculative and as we don't really understand quantum gravity one should take all results with a "pinch of salt", in my humble opinion. All work in progress I would say. Fascinating stuff...

 

 

References

 

[1]M. Bojowald. "What happened before the Big Bang?". Nature Physics 3 (8): 523–52, 2007

[2]G. Veneziano. "Scale factor duality for classical and quantum strings". Physics Letters B 265 (3-4): 287 1991.

Edited June 30, 2011 by ajb

[granpa]

everything didnt come from nothing.

everything came from everything.

 

just because there was a beginning doesnt mean there was a time before that when there was nothing.

there cant be a 'before' the beginning.

 

asking what came before the beginning is like asking whats north of the north pole

[pantheory]

nernico,

 

What created Big Bang? What created the thing that created Big Bang?

These are simple questions with very simple answers generally independent of what cosmological model you adhere to. According to the BB model the BB had an internal potential energy that created the bang. Accordingly there is no such thing as something before that. Although accordingly time is of a finite duration and accordingly there was no such thing as before the big bang since it would be a logical contradiction. I would be like asking what change came before the first change ( a child-like question). Please note that this explanation applies to any cosmological model concerning a finite period of time, not just the standard model.

 

And why is there something rather than nothing?

This is the question Stephen Hawking asked at the end of his book. The answer again is very simple if you will believe this answer Do you believe in flying purple people eaters? No. Why not? because they have never been observed. O.K. good answer. Flying purple people eaters, just like nothingness, is not a possible state of reality, nor was it ever a possible reality. Nothingness just like any other imaginary reality like one including flying purple people eaters is not one of those possible states. -- do you understand? if not keep your questions flying.

Edited July 1, 2011 by pantheory

[michel123456]

(...)And why is there something rather than nothing?

 

Because "nothing" is exclusive.

 

Explaining:

If you define the universe (any kind of universe) as the sum of all mutualy possible things (events), you will immediately see that "nothing" forbids anything else. When only a single one event happens, "nothing" vanishes and "something" takes its place. That makes "nothing" extremely sensible, instable. Like a pencil in equilibrium upon its point.

I whish it could be possible to prove that "nothing" is impossible.

-----------

Edit: the above is my interpretation.

Edited July 1, 2011 by michel123456

[ajb]

Accordingly there is no such thing as something before that. Although accordingly time is of a finite duration and accordingly there was no such thing as before the big bang since it would be a logical contradiction.

 

This is the usual answer based on classical general relativity and standard cosmology. However, people applying models of quantum gravity to the early Universe have pointed towards pre-big bang cosmology. It sounds crazy, but people publish papers on this.

 

The most truthful answer here is that is is simply not known what caused the big bang or what was before the big bang, or even if before has a real meaning. We understand the physics of the Universe close to the "birth of the Universe", but our understanding of the physics at or very close to the "birth" is poor. Simply put one would expect quantum gravity to play a significant role and right now we do not have a great grip on quantum gravity.

 

One general feature we expect is that quantum effects will regulate the initial singularity of the classical theory. You can argue this by suggesting that space-time at or near the Planck length is noncommutative; something like the phase space in quantum mechanics and is thus dived into "Planck cells".

 

Right now sting and brane cosmology is really still in its infancy, as is loop quantum cosmology.

[Amitash]

If anyone knew what was there before a big bang, he will receive the Nobel prize.

[hawksmere]

First should you not ask if time existed before the big bang? Was there an Arrow of time? No mass, no energy, no time?

[Airbrush]

"...According to the BB model the BB had an internal potential energy that created the bang...."

 

"Hawking: '...Flying purple people eaters, just like nothingness, is not a possible state of reality, nor was it ever a possible reality.... "

 

I really like these comments. Before the BB there was potential for BB. Some kind of "internal potential energy" that caused a rapid expansion of stuff, from a region of undeterminable size, at such a speed to overcome gravity. Without this initial motion everything would have just collapsed into a huge black hole. The universe never has been in a non-expanding state.

[pantheory]

Airbrush,

I really like these comments. Before the BB there was potential for BB. Some kind of "internal potential energy" that caused a rapid expansion of stuff, from a region of undeterminable size....

Thanks Airbrush. You would not say "before the BB," instead you might say at the beginning of time the BB entity had the potential energy to "bang." According to the standard model, both time and space were created as the BB progressed so there would be no such thing as before the big bang. Some alternative mainstream versions believe the BB was caused by a fluctuation in the Zero Point Field. In such alternative models there was a time before the BB but not according to the standard version. There are many BB versions with no consensus concerning a beginning big bang entity. There are also many other cosmological models that are generally considered to be either non-mainstream, or no longer are considered mainstream.

 

ajb,

This is the usual answer based on classical general relativity and standard cosmology. However, people applying models of quantum gravity to the early Universe have pointed towards pre-big bang cosmology. It sounds crazy, but people publish papers on this.

 

The most truthful answer here is that is is simply not known what caused the big bang or what was before the big bang, or even if before has a real meaning. We understand the physics of the Universe close to the "birth of the Universe", but our understanding of the physics at or very close to the "birth" is poor. Simply put one would expect quantum gravity to play a significant role and right now we do not have a great grip on quantum gravity.

 

One general feature we expect is that quantum effects will regulate the initial singularity of the classical theory. You can argue this by suggesting that space-time at or near the Planck length is noncommutative; something like the phase space in quantum mechanics and is thus dived into "Planck cells".

 

Right now string and brane cosmology is really still in its infancy, as is loop quantum cosmology.

 

Yeah, you are right. Papers get published because it is still considered an open question. Trying to get a non-BB paper published is a more difficult talk, and often must be done through alternative publishers so that they generally never get read, and remain unknown to the mainstream.

 

As you suggest string theory has not played itself out yet but it is more difficult to get some of these papers published now. Membrane cosmology is directly related to string theory. Loop quantum cosmology involve the implications of loop quantum gravity which for one thing has been an attempt at explaining the Inflation hypothesis. There is still a lot of mainstream room for publications concerning these subjects as you suggest. I don't think Ocamm's razor could apply to any of these models mentioned as being more preferable than another since none are simpler than others concerning their formulations.

 

My expectation is that the "correct" answers will be more obvious/ simpler and in compliance with Occam's razor.

Edited July 1, 2011 by pantheory

[ajb]

Yeah, you are right. Papers get published because it is still considered an open question. Trying to get a non-BB paper published is a more difficult talk, and often must be done through alternative publishers so that they generally never get read, and remain unknown to the mainstream.

 

The evidence for the Lambda CDM model (with inflation) seems overwhelming. I cannot see that any theories that are greatly different to this could be taken very seriously. Any attempts to model physics at or very near the classical singularity must evolve into the Lambda CDM model or something very close. For example the Ekpyrotic Universe model contains the Lambda CDM model after the initial collision of the branes. Detailed studies of the CMBR should be able to distinguish inflation and Ekpyrotic models, but you would have to do a literature search to find out details and the current status. (I believe the inflation model seems to agree with observation extreamly well.)

 

 

I don't think Ocamm's razor could apply to any of these models mentioned as being more preferable than another since none are simpler than others concerning their formulations.

 

My expectation is that the "correct" answers will be more obvious/ simpler and in compliance with Occam's razor.

 

Only nature can really decide this. If a very conceptionally and mathematically complicated theory agrees with nature to some very high accuracy then one will be forced to accept this theory as a good theory. Occam's razor would only help if one has two or more theories that completely agree with each other and nature, up to the domains of applicability etc. Even then, it may not be clear which theory is really simpler.

[pantheory]

ajb,

 

The evidence for the Lambda CDM model (with inflation) seems overwhelming. I cannot see that any theories that are greatly different to this could be taken very seriously.

Any attempts to model physics at or very near the classical singularity must evolve into the Lambda CDM model or something very close. For example the Ekpyrotic Universe model contains the Lambda CDM model after the initial collision of the branes. Detailed studies of the CMBR should be able to distinguish inflation and Ekpyrotic models, but you would have to do a literature search to find out details and the current status. (I believe the inflation model seems to agree with observation extremely well.)

I think there is much evidence that is contrary to the standard model. One of the big problems, I believe, concerns the observed density of the universe. Looking back half the age that the universe is thought to be, about 7 billion years ago at a redshift of ~1.75, the universe would have been denser according to the expanding universe model and the Big Bang, not just by a little but by a factor of 8. There is no evidence that I know of that the universe was ever more dense in the past concerning the density of observable galaxies in that time frame. The second major problem, I think, is that there appears to be very old appearing galaxies as well as large elliptical galaxies as far back as we can presently observe. In the BB model, old galaxies (the age of the Milky Way) could not exist at these distances. Another seeming problem is that galaxies accordingly become large by merging with other galaxies. We know that this happens but is this the primary reason galaxies become large? There seems to be evidence that galaxies grow from the inside out and that galactic type black hole entities might come first. I have a collection of such papers that at least in some ways seem to contradict the Lambda CDM model. Here are a few such links that seem to challenge present-day cosmology concerning the age of the universe.

 

http://www.scienceda...50310102001.htm

http://www.astronomy...f1-9b749d7f8f56

http://outreach.jach...008b/index.html

http://www.cfa.harva...8/pr200821.html

http://www.astronomy...b6-7da4afb9ee0c

 

Of course there are many observations that are also asserted to support the standard model. I think interpretations are a big part of all observations which stretch the limits of what can presently be observed.

 

Only nature can really decide this. If a very conceptually and mathematically complicated theory agrees with nature to some very high accuracy then one will be forced to accept this theory as a good theory. Occam's razor would only help if one has two or more theories that completely agree with each other and nature, up to the domains of applicability etc. Even then, it may not be clear which theory is really simpler.

(bold added)

 

I think some alternative theory's/ models are far simpler than the L CDM (Inflation) model, being different both conceptually and mathematically. Ocamm's razor generally states that the simpler model is probably the better model, all else being equal. The big question always concerns the latter contention, "all else being equal. " I will present such a alternative theory in the Speculation forum if you are interested, since I realize that you are well educated on this subject and could add much to such a discussion.

 

I personally expect that if a model ever replaces the standard model, that such a model will be quite different and also simpler than the L CDM model.

Edited July 2, 2011 by pantheory

[michel123456]

ajb,(...)

I think some alternative theory's/ models are far simpler than the L CDM (Inflation) model, being different both conceptually and mathematically. Ocamm's razor generally states that the simpler model is probably the better model, all else being equal. (...)

 

@Pantheory

 

You are terribly wrong.

It is not Ocamm's razor but Occam's razor.

 

The rest of your post makes some sense.

[between3and26characterslon]

My apologies if I'm hijacking this thread, a Moderator can move it if necessary.

 

On the subject of Occam's razor.

 

You have a system and you have two explanations for that system, one of those explanations is very complex and the other is quite simple. Could one conclude that the more complex explanation would necessarily embibe upon that system a higher entropy and the simpler explanation a lower entropy. Is it not therefore the direction of entropy, from high to low, that gives rise to Occam's razor and thus would indicate that the simpler explanation is more likely.

 

On that note would a universe that has a higher state of entropy require a more complex exlanation than a universe in a lower state of entropy and, as a consequence of that, will our explanation of the universe get simpler as the universe gets older?

 

Of course if two different explanations both give the same entropy to a system then the above is nonsense.

 

(EDIT: I may have gotten the direction of entropy wrong)

Edited July 3, 2011 by between3and26characterslon

[ajb]

I think there is much evidence that is contrary to the standard model.

 

The "modern age problem" (old high redshift objects) is a current area of research and is being tackled by models of dark energy. I would say that such old redshift objects are a great way of testing models of dark energy, rather than something inconsistent with theory.

[pantheory]

@Pantheory

 

You are terribly wrong.

It is not Ocamm's razor but Occam's razor.

 

The rest of your post makes some sense.

Thanks for the correction. I've seen Occam spelled a number of different ways but for that posting maybe I just made up my own version of the spelling, or maybe my right hand just did not know what my left brain was doing

 

The "modern age problem" (old high redshift objects) is a current area of research and is being tackled by models of dark energy. I would say that such old redshift objects are a great way of testing models of dark energy, rather than something inconsistent with theory.

I have not heard of the idea of old appearing galaxies being used to test models of dark energy. Thanks, I will have to research it. I believe dark energy and dark matter are not real but can be explained away simply by "slight justifiable changes" of formulations concerning the Hubble formula and GR.

Edited July 3, 2011 by pantheory

[ajb]

I have not heard of the idea of old appearing galaxies being used to test models of dark energy. Thanks, I will have to research it. I look at such galaxies, in accord with my last postings on this thread, as a contradiction to the expanding universe model as a whole, not just the BB models.

 

Age of High Redshift Objects - a Litmus Test for the Dark Energy Models, Deepak Jain, Abha Dev

http://arxiv.org/abs/astro-ph/0509212v3

 

discusses this. One can use these observations to rule in or out models of dark energy. I am not really sure of the exact status today and this is work on the very frontier of our understanding.

 

As you probably know Hoyle's Steady State models also proposed an expanding universe.

 

The Steady State model has lots of observations that show it to be a very poor model. I would not appeal to difficulties in pinning down the parameters and exact nature of dark energy to resurrect the Steady State model. For example, detailed study of the CMBR fit the Lambda CDM model well, understanding the CMBR within the Steady State model is troublesome. The details of the CMBR do not fit with what one could expect to find within the Steady State Model.

[pantheory]

ajb,

.....The Steady State model has lots of observations that show it to be a very poor model. I would not appeal to difficulties in pinning down the parameters and exact nature of dark energy to resurrect the Steady State model. For example, detailed study of the CMBR fit the Lambda CDM model well, understanding the CMBR within the Steady State model is troublesome. The details of the CMBR do not fit with what one could expect to find within the Steady State Model.

The O.P. question assumes that there was a big bang in the first place. Even the most prominent version of the BB model now does not necessarily include a "bang" beginning, only a hot dense beginning. The dark energy hypothesis is still an open question that I believe will be resolved by the reformulation of the Hubble Formula as I stated in posting #18.

 

Hoyle's Steady State model also includes an expanding universe which many BB followers do not realize. As for me I think the observable universe is not expanding which if valid would make the first part of the O.P. question not relevant. Note: there accordingly would be a different explanation for redshifts.

 

The second part of his question I think is relevant no matter what cosmological model one adheres to: why is there something rather than nothing? For this I gave my answer in posting #6

 

----------------------------------------

 

corrected "dark matter" to dark energy

Edited July 4, 2011 by pantheory

[ajb]

The O.P. question assumes that there was a big bang in the first place.

 

Which given the evidence supporting the big bang this is a reasonable assumption, and is one that sits well with current mainstream thinking in cosmology.

 

 

Even the most prominent version of the BB model now does not necessarily include a "bang" beginning, only a hot dense beginning.

 

Yes, so this I have addressed earlier. Without a good theory of quantum gravity the "bang" will never be properly understood.

 

 

The dark matter hypothesis is still an open question that I believe will be resolved by the reformulation of the Hubble formula as I stated in posting #18.

 

Modified Newtonian Dynamics (MOND) is one example of modifying standard theory to attempt to dissolve the dark matter issue, as in galactic rotation curves. As far as I know, MOND is not well accepted in general.

 

There are other theories that attempt to get rid of dark matter, but I do not think these are also not likely to catch on.

 

Just about all astronomers and cosmologists think that dark matter is real. The evidence for an accelerating Universe is also very good. It is generally accepted that one requires a cosmological constant, quintessence, moduli fields or something similar to explain this.

 

Hoyle's Steady State model also includes an expanding universe which many BB followers do not realize. As for me I think the observable universe is not expanding which if valid would make the first part of the O.P. question not relevant. Note: there accordingly would be a different explanation for redshifts.

 

The Steady State model does indeed have an expanding Universe, but it has many failings. The model has continuously been modified to take account of discoveries. For example the quasi-steady state cosmology appeared as a modified version to take care of some of the initial difficulties. However, this model cannot properly explain details of the CMBR.

 

The Lambda CDM model fits nature far better.

[pantheory]

Which given the evidence supporting the big bang this is a reasonable assumption, and is one that sits well with current mainstream thinking in cosmology.

I agree that the BB model sits well with present mainstream thinking as you state.

 

Yes, so this I have addressed earlier. Without a good theory of quantum gravity the "bang" will never be properly understood.

I agree that this idea is certainly one of the mainstream ideas.

Modified Newtonian Dynamics (MOND) is one example of modifying standard theory to attempt to dissolve the dark matter issue, as in galactic rotation curves. As far as I know, MOND is not well accepted in general.

I agree that MOND has problems but think the same is true with the dark matter hypothesis in general.

 

There are other theories that attempt to get rid of dark matter, but I do not think these are also not likely to catch on.

I made a mistake in my previous posting by saying dark matter when I meant to say dark energy which I just corrected before seeing this posting.

.

Just about all astronomers and cosmologists think that dark matter is real. The evidence for an accelerating Universe is also very good. It is generally accepted that one requires a cosmological constant, quintessence, moduli fields or something similar to explain this.

 

The Steady State model does indeed have an expanding Universe, but it has many failings. The model has continuously been modified to take account of discoveries. For example the quasi-steady state cosmology appeared as a modified version to take care of some of the initial difficulties. However, this model cannot properly explain details of the CMBR.

 

The Lambda CDM model fits nature far better.

I agree that both DM and DE are well accepted today but think both ideas will be replaced in time. Details including the different math formulations can be discussed in the Speculation forum if you wish.

Edited July 4, 2011 by pantheory

[csmyth3025]

My apologies if I'm hijacking this thread, a Moderator can move it if necessary.

 

On the subject of Occam's razor.

 

You have a system and you have two explanations for that system, one of those explanations is very complex and the other is quite simple. Could one conclude that the more complex explanation would necessarily embibe upon that system a higher entropy and the simpler explanation a lower entropy. Is it not therefore the direction of entropy, from high to low, that gives rise to Occam's razor and thus would indicate that the simpler explanation is more likely.

 

On that note would a universe that has a higher state of entropy require a more complex explanation than a universe in a lower state of entropy and, as a consequence of that, will our explanation of the universe get simpler as the universe gets older?

 

Of course if two different explanations both give the same entropy to a system then the above is nonsense.

 

(EDIT: I may have gotten the direction of entropy wrong)

Although there is nothing wrong with pointing out that the correct term is generally accepted as Occam's razor (or, alternately, Ockham's razor), your further explanation misses the mark both it terms of the use of this term and it's applicability to the OP (What was there before the Big Bang?)

 

Occam's razor (or Ockham's razor)...... is a principle that generally recommends selecting the competing hypothesis that makes the fewest new assumptions, when the hypotheses are equal in other respects; for instance, if all the hypotheses can sufficiently explain the observed data...

 

(ref. http://en.wikipedia....s_razor#History )

 

The above is meant to point out that Occam's razor has nothing to do with entropy. The entropy of the universe, in itself, doesn't address the OP: "What was there before the Big Bang".

 

The only thing that can be said about conditions before the inflationary epoch (about 10^-36 seconds after the initiating event of the big bang) is that the universe was very hot, very dense and both homogeneous and isotropic to a very high degree. Anything said about conditions at the instant of the initiating event and, certainly, prior to the initiating event is speculation. As far as I know, we have no means at present to test any hypothesis about this event. The explanation that "...and God said 'Let there be light'..." is as good as any theory that's been postulated so far.

 

Chris

 

Edited for clarification

Edited July 5, 2011 by csmyth3025

[Protium]

I don't know if this is correct, but I like to think of the Big Bang as where time didn't even exist. It was more than paused, and the universe just "began". Time existed all the time the universe has existed, but not before. It's trippy and difficult to explain in words. Just imagine you always existed at the nursery, waiting for someone to adopt you. It's like when a toddler turns 3 and starts becoming concious. The toddler can't remember the conciousness ever starting.

[pantheory]

I don't know if this is correct, but I like to think of the Big Bang as where time didn't even exist. It was more than paused, and the universe just "began". Time existed all the time the universe has existed, but not before. It's trippy and difficult to explain in words. Just imagine you always existed at the nursery, waiting for someone to adopt you. It's like when a toddler turns 3 and starts becoming concious. The toddler can't remember the conciousness ever starting.

I think you pretty much have it right. Time accordingly is equated with changes in reality, or changes in matter. If there was a big bang it was the beginning event and there would have been no such thing as changes before the first change, or time before the first time interval.

.

There are a great number of alternative BB models where time is separate from the BB that accordingly assert that the Zero Point Field or something else existed before the BB. In those models there would be such a thing as before the BB. Most of these models try to explain a cause for the bang or a cause for the hot dense field that accordingly resulted.

Edited July 5, 2011 by pantheory