Before the Big Bang

[Mustrum_Ridcully]

This is physics - our definitions are not vague or hazy. It is either the correct use of the term, or it isn't. When everrone's been taught "Big Bang = beginning of universe" to start referring to "before the Big Bang is highly misleading, and, in fact, brings them to thinking somethign is true, when it isn't. This is kind of opposite the goal of science.

See previous rants about poor science reporting.

"Big Bang" is not a scientific term. it's a colloquial term. Of course they are trying to imply that there was something before the Universe. But if we see the Big Bang as the event of rapid expansion, then yes, there is something before the Big Bang. Typically, Big Bang implies some kind of big explosion. But then, a quantum leap shouldn't describe a major achievement, either.

In fact I remember reading that in some models of our Universe, taking into account the extra dimensions implied or required for String theory, the (visible) universe might just be a "brane" embedded in a larger .... well, multiverse might be another colloquial term. And in some of these models, the spacetime of our universe might have existed before the event of the Big Bang happened.

Of course, I am not sure if "before" is the right term or not, but I think it was.

This is the critical part for defining what they mean by "before the Big Bang". Before the inflation started.

Before the Big Bang?

The model also intriguingly hints at what might have come before inflation, since it suggests that the universe's lopsidedness may be an aftereffect of a great fluctuation that occurred before inflation began.

 

[Umbran]

"Big Bang" is not a scientific term. it's a colloquial term.

Um, no. It's the term the cosmologists use for the event. They call the inflationary period the inflationary period. They have not changed that.

Of course they are trying to imply that there was something before the Universe.

Right. The writers are trying to mislead. This is not good science reporting.

But if we see the Big Bang as the event of rapid expansion, then yes, there is something before the Big Bang.

If we see the Big Bang as the event of the Red Sox breaking "the curse", then yes, there was something before the Big Bang, too - much as Bostonians might argue the fact That doesn't mean I should go and redefine it like that just because it makes my headline better.

In fact I remember reading that in some models of our Universe, taking into account the extra dimensions implied or required for String theory, the (visible) universe might just be a "brane" embedded in a larger .... well, multiverse might be another colloquial term. And in some of these models, the spacetime of our universe might have existed before the event of the Big Bang happened.

Of course, I am not sure if "before" is the right term or not, but I think it was.

It actually specifically isn't "before". Before means "further back along our time dimension". That our time dimension has a zero point at the Big Bang is still central to the accepted cosmological theories out there. The math still has a singularity at that point.

Mayhaps in the future, they'll find a correction or a new theory that changes that, of course, but that's not a basis for reporting it as if that new theory was already in place when it isn't.

Edit: Yes, I have a bee in my bonnet about things like this. Science reporting has an obligation to get it right, gosh darn it! My apologies if I am a bit dogged on the subject.

 

[Mustrum_Ridcully]

If we see the Big Bang as the event of the Red Sox breaking "the curse", then yes, there was something before the Big Bang, too - much as Bostonians might argue the fact That doesn't mean I should go and redefine it like that just because it makes my headline better.

That is one of the many terrible analogies or exaggerations I hate. Yes, using Red Sox overcoming their curse is ridicilous, considering the Big Bang to be the point where the universe exploded (rapidly expanded) is not. It just might not be how it was defined.

It actually specifically isn't "before". Before means "further back along our time dimension". That our time dimension has a zero point at the Big Bang is still central to the accepted cosmological theories out there. The math still has a singularity at that point.

Mayhaps in the future, they'll find a correction or a new theory that changes that, of course, but that's not a basis for reporting it as if that new theory was already in place when it isn't.

Edit: Yes, I have a bee in my bonnet about things like this. Science reporting has an obligation to get it right, gosh darn it! My apologies if I am a bit dogged on the subject.

One might need to be precise, but the problem is we are talking about new discoveries that might require us to redefine certain terms - or at least define them more specifically.

Here's a bit from Wikipedia related "cylcical" model of the world using the idea of branes:
http://en.wikipedia.org/wiki/Inflation_(cosmology)
Cyclic model - Wikipedia, the free encyclopedia

The cyclic universe indicates there is something before the Big Bang. And the theory involved mixing the inflaton and the "curvaton" fields certainly is not the same as the current "Big Bang" theory. (Well, assuming Wikipedia is up to date on the currently accepted model of the Big Bang. To be up to date and precise, I'd have to be in the "scene" and read journals, not the ocassional book, magizine entry or wikipedia)
But then, I find this:

The early hot, dense phase is itself referred to as "the Big Bang",[notes 2] and is considered the "birth" of our universe

So I guess for the inflaton/curvaton model, the Big Bang is still the start and they were imprecise.

The Brane theory (or is it merely an idea, like the holographic universe, nothing with enough foundation to be called a theory?) would indicate that the the 4 dimensions of spacetime exist independently from our universe, but we are limited by the brane of our universe in our movement. We can't go "before" the big bang because we'd have to leave our brane, which we can't (at least not to our knowledge). But there still is a "before" since the dimension goes "further".

 

[freyar]

I mostly have to agree with Umbran; there are two main uses for the words "Big Bang" in modern cosmology, and neither is what they're using in the article. The most precise usage refers to the "Big Bang singularity," the moment at which all spatial points are zero distance apart (more on this in a bit). Inflation would happen after this, as would everything, including the physics in the article. People thinking about the growth of the universe also talk about the "hot Big Bang" (this might be the more common usage), meaning the high-temperature soup of stuff that formed at the end of inflation (in standard modern cosmology) and leads to the formation of light nuclei, etc. Anything before inflation is before this "Big Bang," so it's kind of silly for the article to say something before inflation is before the Big Bang in this sense. Furthermore, knowing 2 of the 3 scientists interviewed in the article, I don't think they would have meant this meaning for "Big Bang" in this context. I can only think they were going for a good quote.

Regarding cyclic universe theories, etc: we believe that a correct theory of quantum gravity gets rid of the Big Bang singularity, so there could have been something before what would have been the Big Bang. That's the spirit of the cyclic models. But I'd emphasize that they are models and not terribly well understood or necessarily well motivated. Some of these do have cute names like "pre-Big Bang" though the main point of them is that there isn't really a Big Bang singularity.

 

[Umbran]

That is one of the many terrible analogies or exaggerations I hate.

Reductio ad absurdum has its place. If their redefinition for effect is okay, mine should also be. The fact that you hate mine shows there's a problem with the idea of redefining the term. What is good for the goose is good for the gander, and all that

One might need to be precise, but the problem is we are talking about new discoveries that might require us to redefine certain terms - or at least define them more specifically.

I would be fine with that, if it was being redefined by those who actually do the science. Scientists redefine stuff all the time, and I'm cool with it. I am far less sanguine about it being done by the press for the purposes of a good headline.

The cyclic universe indicates there is something before the Big Bang.

The Brane theory (or is it merely an idea, like the holographic universe, nothing with enough foundation to be called a theory?)

The term you're looking for is probably, "hypothesis". To be a "theory" a model has to make testable predictions, and so far the cyclical universe and brane models currently don't make any of which I'm aware.

Basically, these things are not currently falsifiable - such models can be very useful to work on, as they may eventually become theory - but until then, we should not be be using them in science reporting as if they were accepted theory.

So, right now, cosmologists still work with a singularity at the origin. Freyar is correct - a correct theory of quantum gravity might bust that singularity, but we don't have such yet. We have a collection of untestable models.