It is possible that the Big Bang is the start of the time. But there is also another possibility: that the Big Bang was only a local phenomenon. In this case the universe would be something much much bigger and almost void. Maybe there are other regions with matter, but so far away that we cannot interact with them, and the light coming from them just dissipates on the way. Maybe there is a law of Nature, that if some very big region of the universe is too empty, there must occur there a local big bang creating some matter, such that a kind of equilibrium is recovered.

If we think on the way Physics developped since now, it was always like this: physical theories (like Galileo's mechanic, and so on) proved to be only local and partial good descriptions of reality. I do not see why the Big Bang Theory would not be also only a local approximation of the universe, which proves false if seen at a bigger scale.

Words such as "before" or "after" refer to a temporal scale. This temporal scale came into existence at the moment of the Big Bang (at least in the standard cosmology in which the Big Bang refers to the initial singularity). Therefore, the phrase "before the Big Bang", while grammatically correct, has no meaning.

Let me give you an analogy. Suppose you take a trip to the North Pole. When you are at the North Pole, can you go any further north? Can you discuss places that are "north of the North Pole"? It's not so much that there is "nothing north of the North Pole" as the phrase itself, "north of the North Pole", is meaningless.

Or suppose you have some high tech drilling equipment and you dig a really deep hole. At around 6370 kilometers of depth, you reach the center of the Earth. Can you dig any deeper? At the center of the Earth, all directions are "up". There are no places "deeper than the center of the Earth".

Similarly, "before the Big Bang" has no meaning. So you don't have to imagine any "nothing"; you would first have to imagine the meaning of "before the Big Bang", but it has no meaning.

This is in a standard cosmology. There are alternative cosmological models that, e.g., predict a cyclic or "bouncing" universe, in which the "Big Bang" refers to a time when the universe is very (but not infinitely) hot and dense, but there was no singularity, and the universe existed in a contracting phase before the Big Bang. Going back to the North Pole analogy, it is as if the planet was attached to another planet's South Pole at our North Pole, so when you reach the North Pole, you could continue your northward trek by stepping onto the other planet.

Dear Toth

Very nice and considerable analogy you did. I just try to understand all cosmological arguments, if I can.

Thanks

Regards

Let us suppose that the big bang, instead of being a 'something from nothing' event, was, instead, a change of state - let us say, a change from 'unity' to 'plurality'. Then it may well be true that associated with this event was the beginning of 'linear time'. It might also be true that 'linear time' is meaningless outside of the context of this universe (or 'state of being'). However, our metaphysics can concede the possibility, however strange that it may seem to us, that there may be a state of being that does not involve 'linear time'.

Perhaps, there are dimensions of existence that are simply unimaginable from the perspective that our 'state of being' affords.

I suggest that if there is meaning to the question that your are posing then the answer would most certainly involve one of two options:

Either, the state of being before the Big Bang was timeless!

Or, the state of being before the Big Bang was 'time' itself - given that time is only linear given a plural state of being (whatever THAT means).

V. Toth,

A Big Bang arising out of nothing at all does not seem very intellectually satisfying. 'Something' must have given rise to the BB for the BB to be able to happen in the first place, it seems to stand to reason that absolute nothingness would have gone on just so. There are very many models as to what that something may have been.

Your affirmation Quote " This temporal scale came into existence at the moment of the Big Bang" is unproven, and in science it's a good idea to prove rather than to simply state.

Martin Bojowald's model , for instance, concludes that time must have started before the BB or the BB could not have happened to begin with. Even if you don't agree with loop quantum gravity, there are many compelling hints that the story is far more complex than meets the eye.

For instance, and in no particular order, infinite time seen from within a black hole is actually finite when seen from outside the BH. Hence, Nikodem Poplawski -type models.

Delayed choice experiments prove that time is not necessarily linear.

Let us not even begin on Alan Aspect and Nicolas Gisin experiments which hint at time not being local and being multiple-D in unexpected ways.

And so on - there are many more such counter-intuitive, baffling experimental results, underpropped by mathematics (Schrödinger etc.).

Truth is much stranger than fiction, and frankly simple, 'common sense' explanations have utterly lost their right of abode. Our primitive past evolved our instinctive 'common sense' view of things - long since laid to rest by Quantum mechanics, relativity, and frankly most of modern science.

Bottom line, there is no shred of proof that time began at the BB, but there is much proof that time is far more complex and counter-intuitive than we'd think.

Now you may properly argue that even if time did not begin at the BB, it must have begun some-when, and that moving the issue a few steps sideways does not solve it. That is true unless ..... variously, time be shown to be circular and bootstrapping itself, or time is but an epiphenomenon - a side effect- of something else deeper that is actually more readily understandable/graspable, or .....etc. etc. There are quite a few thrilling models of what time actually is. Decreeing that time began at the BB is something that Pope John XXIII once said (to Stephen Hawking, no less), but that any scientist probably ought to grain-of-salt .

Chris, I simply stated what the standard theory says. This is a statement of fact about the standard theory, not a matter of opinion. I am not affirming that this is the way the universe is, I am simply stating that this is what the standard theory asserts.

As I indicated in my answer, there are alternatives to the standard cosmology in which there is no initial singularity, hence there is "time before the BB".

I am not arguing in favor of one or the other. I was simply trying to provide a factual answer, instead of promoting any specific viewpoint, and I tried to elaborate on the least intuitive aspect of the standard cosmology, namely the meaning of the "beginning of time", i.e., an initial singularity.

Dear Dr Toth,

Even as I was writing my comment I was wondering if you would take it as a reply to your own contribution.

Actually, I was just putting my own point of view - no offence.

Best

Chris

Now I am thinking that I have made an error - which Chris?

Probably H Chris :-))))

In any event many thanks are in order to V.Toth for the clarification

Big bang is a theory that is still not proven. But even if it is, let us assume, then we take the beginning of time from the point of Big bang itself. Hence, since the time only started with the big bang, I dont think there is anything before time itself... It is just like the point of absolute zero temperature(0K), where we cannot go further below it...

Abdulvahed,

I am not criticizing your question with this statement, but my understanding of what caused so many physicists and astronomers to deplore and shrink back from the notion of the Big Bang was the fact that it was a point beyond which they could not see. It must be acknowledged that science encounters a Ne Plus Ultra, a "No More Beyond" barrier at the Big Bang.

Aren't we sort of "theorizing in the void" if we speculate about this? It would appear, based on all of my reading, that this is simply a point beyond which we can never go. So doesn't this question throw open the topic to all manner of speculation? By what standards can we evaluate claims or theories about what occurred prior to the Big Bang?

Akash - how do you explain the background radiation of the universe? That seems to have been the discovery which established the veracity of the Big Bang. Some of the best scientific minds of the day fought against this idea and then surrendered when Penzias and Wilson discovered the Cosmic Microwave Background. What makes you doubt its accuracy?

Big bang theory is still not proven as aaksh has already said. According to sir stephen hawking there is nothing before big bang .. And i also think the same because we can't imagine anything before time .. If there is no time there is nothing ..!!

Palle Yourgrau, in "A World Without Time" (Penguin Books, 2007), points out that Kurt Gödel proved in 1949 that no universe compliant with General Relativity can experience [a flow of] time - what he calls "intuitive" time. A time dimension exists but only as a chronological map on which events are located. He complains on behalf of Gödel that this research has been ignored for 50 years because scientists and non-scientists found the implications so uncomfortable. Hawking even proposed a "chronology protection conjecture" to eliminate the "Gödel Universe" but it did not attract support and in 1999 Julian Barbour, with "The End of Time" (Weidenfeld and Nicholson), brought Gödel's proof into the mainstream, where it is now accepted by many physicists. A recent question in ResearchGate asks "Is the flow of time an illusion?" which may reveal a flaw in the roof or a counter example but somehow I doubt it. In this case the question of what happened before the BB becomes meaningless but there are many challenging issues to discuss. Can there be cause and effect? Does force have any meaning in a timeless universe? How to reconcile quantum theory with timelessness? How to account for the entropy gradient in chronological time? Just to start with …..

I can imagine nothing in the form of St. Johns, Michigan at 8:30 pm on a Saturday. However, there's also the Schopenhauer approach to this, the pre-existing, perhaps transcendent "will." Even a pessimist can imagine something out of nothing. I am recalling also Bergson's notion of duration and Whitehead's attempt to make Relativity metaphysical: everything is in process. An old acquaintance of mine, Nathan Oaklander did a compendium on time philosophy and theory that explores things from McTaggert's Paradox, a question of whether time is "past-present-future" or "before-after." But then there is the theoretical possibility that it was "strings" that lacked the will to curl into a "world sheet" and vibrate bosons and fermions. No space/time, no national park access. Warren's summary of Godel suggests, too, that time is quite imaginary: Godel could only imagine what he was describing. I can only imagine Godel and cannot type an umlaut. Everything begins with the imagination and we cannot imagine before its existence.

Scott - You have to use the ö symbol from the insert>symbol menu in Word. I'm afraid we have inadvertently lowered the tone of this debate! I have 15 books on time. They all describe the consequences of relativity (inability of two observers to agree on the simultaneity of two events) for time but offer no counter-arguments and inexplicably then simply pass on to some other aspect of time. Only two or maybe three deal with the issue at the level it justifies.

It would seem that the source of answers to the question of whether it was "something" before the Big Bang, lies in answering the question of whether there was a lapse of time before the Big Bang.

I think, that this way of thinking also leads nowhere. Even if we agreed that the passage of time (in our modern sense) began exactly with the Big Bang, it's not it means, that before the Big Bang there was nothing. This could be, for example, only evidence that what existed before the Big Bang was a "uniform", and there was not other object, with respect to which we can speak about a lapse of time.

A while back, in response to a similar question, I offered the following analogy: what is north of the North Pole?

That question of course is meaningless. When you are at the North Pole, every direction points south. You cannot go further to the north. You can't even imagine what is "north of the North Pole" because the question itself is illogical.

The same way, if the Big Bang scenario is valid, at the initial singularity, every spacetime direction points towards the future. There is no past. The phrase, "before the Big Bang", has no meaning. There is no answer that you can or should try to imagine; the question itself is a logical fallacy.

Others suggested that the Big Bang scenario remains unproven. Perhaps. There is strong evidence (both theoretical and observational) supporting its validity, but alternatives have certainly been proposed, including "bounce" and "cyclic" models. In these models, questions about "before the Big Bang" are meaningful and, in fact, quite important as the conditions of the universe in the contracting phase may have direct relevance to the conditions of the universe today. And yes, in these scenarios, there was plenty of "stuff" before the Big Bang, including contracting matter and energy, exotic fields, perhaps a reversed arrow of time, all sorts of interesting ideas that have been published over the years. Certainly not "nothing".

But in the standard cosmology (the so-called Lambda-CDM concordance model) "before the Big Bang" is a meaningless phrase.

There is no flow of time. The multiverse, of which our universe is an infinitely small part, simply "is". We do not perceive the world directly. We do not see the pattern of rods and cones activated when light passes through our eyes and falls on them because our brain intercepts the electrical signals and converts them to a recognisable image. It is the same, mutatis mutandis, for our other senses. Our image of the world is never objective,but is created by our brains. We (and other animals) feel time passing because this is how our brains make the world intelligible to us. It has no objective reality, it's just a trick. Many people find this impossible to accept but it is true. We experience our whole lives continuously but we are not aware of it because every moment feels like "now". See the thread

https://www.researchgate.net/post/Is_the_flow_of_time_an_illusion

We are used to think in terms of cause and effect, which leads us to infinite regress, but we need to learn t think of sequence rather than change. I hope that if we can start to think in this way we will develop a better and deeper understanding of the nature of our universe. Quantum theory and M (String) theory both need a new impetus.

The flow of time thread prompted me to think of what a 4D universe would look like, which reminded me that it depends on the scale and led me to some calculations that I posted on that thread and of which I copy an edited version below:

"One of our difficulties is that we are looking at the Universe through the wrong end of a telescope. Evolution has led us to look at the world on the human scale. We measure things in human scale units: seconds, minutes and hours for time, meters and centimeters for space and grams and kilograms for mass.

The natural units, however, are the Planck units:

Time 5.39912 x 10^(-44) seconds

Length 1.616 x 10^(-35) meters

Mass 2.176 x 10^(-8) kg

The number of protons in the Universe is estimated at about 10^80, matched by about 10^80 electrons, mostly in the form of hydrogen. Let us assume that each of these has, on average, changed quantum state N times in the approximately 13.70 billion year (4.3 x 10^16 seconds or ~10^60 Planck Units) duration of the observable Universe. This represents a gradient of N x 10^20 changes per hydrogen atom per natural unit of time for the lifetime of the universe. This would mean that the chance of any individual atom being in a different state between two adjacent time quanta is 10^20 x N/10^80 or N x 10^(-60). For any remotely plausible value of N (bearing in mind that on average there will be a downhill gradient and the scope for change will decline at higher values of the t coordinate), the Universe is now, on average, virtually featureless at the Planck scale."

I don't know about the validity or relevance of this calculation - any suggestions would be welcome.

It is possible that the Big Bang is the start of the time. But there is also another possibility: that the Big Bang was only a local phenomenon. In this case the universe would be something much much bigger and almost void. Maybe there are other regions with matter, but so far away that we cannot interact with them, and the light coming from them just dissipates on the way. Maybe there is a law of Nature, that if some very big region of the universe is too empty, there must occur there a local big bang creating some matter, such that a kind of equilibrium is recovered.

If we think on the way Physics developped since now, it was always like this: physical theories (like Galileo's mechanic, and so on) proved to be only local and partial good descriptions of reality. I do not see why the Big Bang Theory would not be also only a local approximation of the universe, which proves false if seen at a bigger scale.

I am not sure if that works since there is no simultaneity at a distance; all time is local. Space time can be any size but there is no way to calculate the expansion of time separately from space.

In "The Life of the Cosmos" Lee Smolin argues (or perhaps conjectures) that every black hole is the source of a new big bang and a new universe.  If it is assumed that the daughter universes each have physical laws similar to those of their mother then the multiverse should be dominated by those with the highest rate of black hole formation.  Smolin admits that he hasn't done a real analysis but that some back-of-an-envelope calculations suggest that any significant change to our physical laws would tend to reduce the number of black holes formed.  So ... maybe we are a typical member of the multiverse. 

What happens when the universe ages to the point when black holes evaporate? I guess we all go together (more or less) when we go.... unless you believe in block time, where past present and future already exist and time is not a turbulent river but a frozen lake.

Dear All

Thank you for your contributions.

Regards

Stefan, it may be all a bit more complicated, and independent of questions of semantics. Very many models of reality demand that time itself pre-exist the Big Bang for it to be able to happen in the first place (see e.g. Martin Bojowald , etc.) Then there are the issues of incompressible uncertainty, which prevent pinpointing infinitely exact moments in time.  Then there is the possibility that the topology of time is so counterintuitively non-linear that we are unable to grasp it properly (there are environments when this is demonstrably the case.) Then there is the possibility that time itself is an illusion, a side effect emerging in the lower dimensions of a purely mathematical universe. And so on ...

In our PFO-CFO Theory of Solar System Formation (in its cosmological portion) we start  from the statement that Space is eternal and infinite, represents the mass/energy of a low potential, and Universe originated and exists within Space having this mass/energy as the material for its origination and development. We state that no big bang occurred; the notion of big bang resulted from GR, which is erroneous, because it was taken with no grounds that the gravitation potential and the light speed are constant over Universe.

Thus, answering your question, I write that mass/energy existed always in the form of Space and no big bang occurred. 

The PFO-CFO Theory explains the Universe history, including formation and transformation of the Sun and Solar System and forecasts the future of the Earth. The publications of the PFO-CFO Theory are available at the ResearchGate site by addresses: 

https://www.researchgate.net/profile/Victor_Ostrovskii

https://www.researchgate.net/profile/Elena_Kadyshevich

Dear All Thank you all for your scientific answers. I (as not a physicist) can not imagine anything without time. It is very hard to imagine that "time" is a result of an event in universe, such as big bang or any other event.

On the other hand, it is harder to imagine "time" without "start".