What was before the big bang ?

[sero]

I had a discussion with some friends about this. I figured this would be a great place to get a real anwser ( since we are all want to be's )

What was before the big bang ? There had to be something in order for the matter that was there to be condensed in the first place right ?

Did time exsist before the big bang ? I say it did but a friend is saying it only started when the big bang occured.

happy friday

 

[Integral]

The big bang is the beginning of space time as we know it. We can not even make a conjecture about any thing pre big bang. The general consensus is that there was nothing, neither time nor space before the big bang. The big bang did not happen in space it happed TO space.

 

[misogynisticfeminist]

There are actually quite a few possible alternatives, even though most of them are somewhat speculative. string theory predicts branes colliding which causes the bang, there is also a theory (or so I've read in scientific american) closely related to strings that a pre-bang universe like ours existed, suddenly collapsed into a singularity then bursts out again (not too sure about the details though).

May be wrong...

 

[setAI]

...The general consensus is that there was nothing, neither time nor space before the big bang...

actualy the consensus is an infinite/eternal Multiverse out of which big bangs emerge- not a unique Big Bang from nothing-

the idea of a big Bang from nothing was a briefly popular error among cosmologists commonly referred to as the fallacy of creation ex nihilo which Spinoza/Hegel demonstrated to be absurd/irrational centuries ago- it was a case of too many physicists not posessing a firm enough foundation in Philosophy or Logic- or none of them would ever have so embarassingly suggested the concept in the first place-

creation ex nihilo is AXIOMATICALLY absurd

 

[selfAdjoint]

actualy the consensus is an infinite/eternal Multiverse out of which big bangs emerge- not a unique Big Bang from nothing-

the idea of a big Bang from nothing was a briefly popular error among cosmologists commonly referred to as the fallacy of creation ex nihilo which Spinoza/Hegel demonstrated to be absurd/irrational centuries ago- it was a case of too many physicists not posessing a firm enough foundation in Philosophy or Logic- or none of them would ever have so embarassingly suggested the concept in the first place-

creation ex nihilo is AXIOMATICALLY absurd

Phooey! An axiom comes out of our minds and has no binding power on what the univrse does. I can't imagine scientists being bound by the lucubrations of Spinoza and/or Hegel (much as I respect both men) any more than they are bound by the stories in Genesis.

 

[marcus]

... a theory (or so I've read in scientific american) closely related to strings that a pre-bang universe like ours existed, suddenly collapsed into a singularity then bursts out again (not too sure about the details though).
...

You probably read about the work of Martin Bojowald
(universe has a prior contraction phase)

Here is a recent piece in Nature Journal about Bojowald
http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v433/n7021/full/433012a_fs.html

 

[Chronos]

The ultimate question and one which may never be satisfactorily answered. The uncertainty principle [and some would claim Godel's theorem] already constrains our ability to make predictions at the most fundamental levels of reality. Yet, oddly enough, the uncertainty principle may hold the key.

Creation ex nihilo is no more absurd than an infinite cycle of universes begetting universes, or other ad infinitum pre-existing constructs. If a poll has been taken among theorists, I have not seen it. So far as I know, the consensus on what preceeded the big bang ranges from unknown to unknowable. All such theories are regarded as speculative. Authors and relevant papers are too sparse to suggest any such theory enjoys broad support.

Theoretically, a universe from nothing has a sound theoretical basis: something multiverse and other scenarios are hard pressed to claim. Quantum theory, which has been experimentally validated, provides a mechanism for creation ex nihilo. I just happen to have a few links:

Birth of the Universe
http://zebu.uoregon.edu/~js/ast123/lectures/lec17.html

Simple quantum cosmology: Vacuum energy and initial state
http://arxiv.org/abs/gr-qc/0501014

Future and Origin of our Universe: Modern View
http://arxiv.org/abs/astro-ph/9912054

Can the Universe Create Itself?
http://arxiv.org/abs/astro-ph/9712344

 

[Entropy]

actualy the consensus is an infinite/eternal Multiverse out of which big bangs emerge- not a unique Big Bang from nothing-

the idea of a big Bang from nothing was a briefly popular error among cosmologists commonly referred to as the fallacy of creation ex nihilo which Spinoza/Hegel demonstrated to be absurd/irrational centuries ago- it was a case of too many physicists not posessing a firm enough foundation in Philosophy or Logic- or none of them would ever have so embarassingly suggested the concept in the first place-

On the contrary, the concept of a multiverse is absurb because the word "universe" means "everything." So really the universe would be the "multiverse." So now back the question. Where did it come from and what was it like before it? Oh, wait. The "multiverse" theory comes right back to the same problem it was suppost to solve!

 

[errorist]

:uhh: Foreplay?

 

[Phobos]

We can at least say that Big Bang theory applies to the visible universe.

 

[setAI]

point one: none of the many ideas/conjectures suggesting that the Universe emerged from nothing actually posit that it came from TRUE Nothing- Nothing is Nothing and if any kind of chaotic quantum fluctuation [hmmm- QM is already background dependant anyway!] or ANY kind of event comes from this "nothing"- it is NOT nothing but Something by definition- true Nothing has no extent/duration/dimension/form/or causality Nothing has no qualities WHATSOEVER- not even the quality of EXISTENCE- therefore no events and no being/existence of any kind can emerge for it- there is no IT to emerge from! anything less than this absolute is NOT nothing at all-

point 2: even if our universe came from a true Nothingness- if a universe requires nothing to come into existence then there is NO rational way to suggest that universes aren't continuously/eternally being born!- many state that one cannot assume other universes when we can only see ours- but I think it is easy to show the opposite is unavoidable: if a universe can come from nothing- then it literally needs nothing to Be- therefore there is no way to avoid an infinitude of universes unless you posit a god-like mechanism that prevents others from being born and only allows this one unique world to exist- so to me the suggestion that there is only one universe is not at all the simplest explanation and is quite untenable- the idea that we can only assume our universe requires a mystical/magical mechanism to prevent other worlds from popping out of literally nowhere! that is far more speculative and fanciful than any primitive mythology by far!

ultimately given that Nothing cannot really be Nothing- and that other universes are unavoidable when they require nothing to be born- reason necessitates that the idea of Creation ex Nihilo is actually the SAME idea as that of an eternal multiverse! the disagreement comes from using different definitions for "nothing" the error of Creation ex Nihilo is not that it is wrong- but that it is right and doesn't address the consequences of being right so it just misleads- it is a conclusion jumped at too soon-

On the contrary, the concept of a multiverse is absurb because the word "universe" means "everything." So really the universe would be the "multiverse."

you know as well as I that the definition of universe as everything is long past- universes-plural is now such a ubiquitous concept that even school children and soccer moms have heard of "parallel universes"- and a quick search of the word "universes" on the arXiv yielded more results than the search engine could display [300+]

So now back the question. Where did it come from and what was it like before it? Oh, wait. The "multiverse" theory comes right back to the same problem it was suppost to solve!

an ETERNAL multiverse [or if you prefer a timeless nothing-like void out of which chaotic quantum fluctuations give rise to universes] has no origin problem- something which always has existed has no need for a creator or a birth mechanism- "it simply IS" as Hawking stated- and is always the simplest solution to the fundamental existence of the Cosmos- it's the real Answer beyond "42"

back to the main point: I think all of this is ultimatley why virtually every major cosmologists/theorist has published a paper or article with their own multiverse-model-du jour- it's not really hard science but the fundamental ideas of a multiverse simpy cannot be ignored out of existential/ontological necessity

 

[Chronos]

It's a thorny problem, for sure. That's why this stuff is called speculative. What we know from what we can see indicates what we now refer to as the universe [time, space, matter and the four fundamental forces of nature] emerged from a formless state where they did not have separate identities or definable properties, at least not in terms to which we can relate. Is this nothing? Good question. 'Nothing' is surprisingly hard to define. One of the links I posted puts it this way:

The properties of the Universe come from `nothing', where nothing is the quantum vacuum, which is a very different kind of nothing.

The philosophical concept of 'nothing' is an absolute, a state that is not even a state. It cannot be ascribed any properties whatsoever without becoming a philosophical 'something'. Such a state is obviously nonphysical, which renders it useless for scientific purposes. All kinds of otherwise well established theories, like GR, produce nonphysical solutions when you consider all possibilities. Those solutions do not invalidate the theory, they are merely ignored. I have one more excerpt:

In this sense, the Universe is not filled by the quantum vacuum, rather it is `written on' it, the substratum of all existence.

So indeed, the universe did not arise from a philosophical 'nothing', rather it emerged from a background state that is implicitly undefinable. That is about as good a description of 'nothing' I can think of that is not unphysical.

 

[Nereid]

Another thing to keep in mind: homo sap. has done scientific work on this question for only a trivial fraction of the age of the universe (and 'scientific' itself is, perhaps, an even more recent 'invention'); is it not a measure of our hubris that we think we have even the most tenuous handle on answers to sero's question?

 

[marcus]

...What was before the big bang? ...

:uhh: Foreplay?

(Loop Quantum Cosmology infers the foreplay)
https://www.physicsforums.com/showthread.php?p=435930#post435930
here's a list of Bojowald's papers,
http://arxiv.org/find/grp_physics/1/au:+bojowald/0/1/0/all/0/1
there were 48 of them last time I looked,
almost all in LQ Cosmology

 

[Enos]

uncertainty principle, bah.

 

[Gold Barz]

So Chronos, what was before the Big Bang was some kind of field or state that is unexplainable...how about the universe emerging from a quantum vacuum like that one link states?

 

[Nereid]

So Chronos, what was before the Big Bang was some kind of field or state that is unexplainable...how about the universe emerging from a quantum vacuum like that one link states?

Yeah, why not?

Then again, maybe 'before the BB' was a state of knaseroth-ness, in which everything was infused by oihntrokno, and then along came qweradvnk, and BB!

If you're taking a scientific approach to this, you have to ask 'how could you tell?'

 

[Chronos]

Among the big questions in cosmology is, could the precursor state of the BB leave a trace signature in the background? So far, the data has only affirmed the post emergent state has left a trace.. and it is remarkably consistent with the predictions of a hot big bang model [modern theory]. No one is really shocked by that discovery.. they are only puzzled by the new questions the data alludes to. That's why science is fun. Every time we peer deeper into the universe, it opens up a new puzzle box.

 

[Gold Barz]

There had to be some kind of field or state before the big bang, that "something out of nothing" is really confusing to me it doesn't make sense, quantum field maybe radiation field from a pre-existing space...i can't really explain it

 

[chronon]

Suppose we think of the steady state universe. Then time is in the set $$(-\infty,+\infty)$$. In the big bang universe time is in $$(0,+\infty)$$. In the first case we don't ask what happened before $$t=-\infty$$, but in the second case we do ask what happened before $$t=0$$. Why should this be? One can transform between $$(0,+\infty)$$ and $$(-\infty,+\infty)$$ with a simple change of variable, so as I see it they are essentially equivalent. It seems perfectly reasonable to me to say that $$t<=0$$ doesn't exist, as it would be saying that $$t<=-\infty$$ doesn't exist .

 

[Gold Barz]

The consensus right now is that the universe came from a vacuum or some sort of pre-existing field that we cannot comprehend...not "absolutely nothing"

 

[cosmoboy]

no big bang !

No matter which approch wetake I think we can never prove either there was a big bang or not.

I know 'hot big bang cosmolgy' have meet many so called
observational evidences like huuble expansion, cmbr, light element synthesis and others. These observations do not prove unambigiosly that big bang did happen.

In my opinion it was unfortunate when Hoyle (he never liked this model)coinded the term 'big bang' . It has created a lot of miscoceptions. Even today if we survey: how many people who heared about the big bang believe that it was an explosion than I think more than 90 percent will agree. Which is totally wrong.

BIG BANG IS THE BREAKDOWN OF THE LAWS OF PHYSICS (WHICH WE KNOW, PARTICLARLY GTR) NOT A PHYSICAL EVENT.

I will be thankful if somebody through some more light on the following points.

1.SPACE AND TIME DID BORN WITH THE BIG BANG. I THINK THIS
IS ONE OF MOST CONFUSING POINTS OF MODERN COSMOLOGY. I
DO NOT KNOW WHAT IT MEANS.

2.UNIVERSE ITSELF IS EXPANDING (SPACE BETWEEN OBJECTS IS STRETCHING) NOT THE OBJECTS IN IT, LIKE GALAXIES ARE MOVING.

Currently there are mainy theories coming up which do predict what was before the big bang or the nature of big bang. Out of these the following are very interesting and
I do not see a bright future of big bang theory.

1. Cyclic Universe
read this here
http://wwwphy.princeton.edu/~steinh/

2. Loop quantum gravity
there is seprate section in this forum read there

3. String theories
3. Inflationary theories

bye

 

[Garth]

Suppose we think of the steady state universe. Then time is in the set $$(-\infty,+\infty)$$. In the big bang universe time is in $$(0,+\infty)$$. In the first case we don't ask what happened before $$t=-\infty$$, but in the second case we do ask what happened before $$t=0$$. Why should this be? One can transform between $$(0,+\infty)$$ and $$(-\infty,+\infty)$$ with a simple change of variable, so as I see it they are essentially equivalent. It seems perfectly reasonable to me to say that $$t<=0$$ doesn't exist, as it would be saying that $$t<=-\infty$$ doesn't exist .

Just to note that these two times in the sets $$(-\infty,+\infty)$$ and $$(0,+\infty)$$ are the two times of the Jordan and Einstein conformal frames respectively of Self Creation Cosmology. (Does that make me a 'two-timer'?)

There is no 'before the big bang' in that theory, $$t < -\infty$$ does not exist.
Garth

 

[Gold Barz]

"How can 'nothing' do anything at all, let alone create an entire universe?

When physicists say 'nothing' they are being playful with the English language, because we often think of the vacuum as being 'empty' or 'nothing' when in fact physicists know full well that the vacuum is far from empty.

The primordial 'state' at the Big Bang was far from being the kind of 'nothingness' you might have in mind. We don't have a full mathematical theory for describing this 'state' yet, but it was probably 'multi-dimensional', it was probably a superposition of many different 'fields', and these fields, or whatever they were, were undergoing 'quantum fluctuations'.

Space and time were not the things we know them to be today because our world is a lot colder than the way it started out.

Nothingness was not nothing, but it was not anything like the kinds of 'somethings' we know about today. We have no words to describe it, and the ones we borrow (that are listed in the Oxford English Dictionary) are based on the wrong physical insight."

i think multidimensional is the key word

 

[s3nn0c]

Personally I like the model of "creation" which has been proposed by Michal Heller. It's based on noncommutative geometry. Unfortunately I don't know the mathematics behind NCG, but Heller writes many popular articles and books (in Polish, unfortunately... for you :-) ). In one of his latest books, "Poczatek jest wszedzie" ("The beginning is everywhere") he describes his (simple) model of Universe. (BTW - this book is imo as good as the best Greene's or Hawking's books, but... more innovative :-) )

In his model, space and time disappear in Planck scale. There is no space, no time, but there is a well-defined dynamics of global states. I like this idea, because in my opinion the problem with the beginning of our universe is in our assumption that there is a beginning. In a mathematical space where time and space are always and everywhere, the problem disappears, because our question is simply wrong.

 

[Chronos]

There are of course ways to duck the question of a 'beginning', hence what came before. I don't think they solve anymore problems than they create. I prefer to take the observational evidence at face value. These are a few of what we currently believe to be facts
1] objects in the universe were closer to each other in the past
2] the universe was hotter in the past
3] the universe is observationally finite in time and distant objects appear younger versions of more nearby objects.
These 3 'facts' have extensive and extremely good observational support. When you hypothesize this means the universe was extremely dense, and enormously hot a very long, but finite time ago. You find it suggests a number of other things we should, and do see evidence of - CMBR, elemental abundance over time, evolution of large scale structure, to mention a few. Sure, we see a lot of stuff we cannot yet explain, but, not a single thing that incontrovertably refutes the hypothesis. Until that happens, BBT is not going to die easily.

 

[meteor]

I think that the Standard Model of Cosmology fails at the beginning because is unable to unify at those moments GR with Quantum Mechanics, so I think that a quantum gravity theory will be needed. Like others posters in this thread have indicated, in one of these theories, LQG, there's a phase anterior to the Big Bang, and at the end of this phase
there's the Big Bang, that is not a singularity. However, a doubt that I have is: does in LQG our observable Universe appears from a point like in the Standard Model or not?
If not, what was the volume of the region that grows to our actual observable universe at the era of the Big Bang? The use of the word "singularity" in the Standard Model is misguiding sometimes in my opinion

 

[marcus]

... observable Universe appears from a point like in the Standard Model or not?
If not, what was the volume of the region that grows to our actual observable universe at the era of the Big Bang? The use of the word "singularity" in the Standard Model is misguiding sometimes in my opinion

since I am not an expert, and have imperfect memory, I have to research before answering but I will tell you my initial reaction to the question.

the volume of some region becomes an operator in the quantum theory, an operator with a spectrum of possible values which it may take.

I am not sure that one would be able to assign a definite number to be the volume of the region you ask about------the region which subsequently expanded to be our observable universe.

I remember reading that there is a maximum density which can be reached during the bounce, and that there is a welldefined quantum operator corresponding to measuring the density, and that it has a spectrum with a maxium possible value. This maximum achievable density, if I remember correctly, is on the order of the Planck density (the Planck energy, or mass, contained in the Planck volume)

but instead of trying to remember, I should really go and look for some LQC papers that are somewhere in my study.

You know meteor, quantum geometry is not completely intuitive, there is for example a geometric "Uncertainty Principle" where if you have two surfaces which INTERSECT then their two area operators do not COMMUTE. that is, the two quantum operators corresponding to measuring the areas of each surface cannot be simultaneously diagonalized!
this is very strange. as if one said that if the area of one surface is measured then the area of the other is poorly defined. this is against normal logic.

However, that said (that one cannot always used common sense) I think your question is very interesting because of this: if one knows the maximum density of a region at some time, and at some later time, then one can think about calculating how much it has expanded and what the volume was at the earlier time. Unfortunately it is not quite simple because there is the trouble with inflation. Inflation creates matter! apparently violating the conservation of energy. So that makes it more complicated. But still some calculation should be possible.

One should be able to get some handle on the volume of the region which has expanded to be the part of the universe which is observable to us at this moment.

 

[Nereid]

To extend marcus' point ... it's a curious thing that we homo sap.s can ask questions like 'what was before the big bang?' and 'did time exist before the big bang' and write things like 'Then time is in the set ()'. From our everyday experience, we expect that the first two make sense (implicitly assuming certain things about the BB), and that the third has some meaning outside math.

Yet when we dig into it a bit, we see that 'the big bang' is a theoretical construct (a very good one, in that it is consistent with a great many good observational and experimental results), and that its domain of applicability does not - and cannot - extend to 'before the first Planck second'. We also see that tentative theories (such as M Theory, LQG) which do have a domain of applicability greater than that in which the big bang lives characterise 'time' and 'space' in a way that is completely unintuitive.