Is Big Bang true?

gvgomez

Then please explain the well known hubble photo of a quasar with a galaxy in the background.

Chalnoth

Tell me: why are you so sure the quasar is in the foreground?

Vanadium 50

I'm afraid that Mr. Gomez won't be around to answer that.

DNMock

From what I have read it would seem that the current big bang model is the Newtonian gravity of our time. It does a great job of explaining what can be observed but still has some flaws in it's origin just like Newton's gravity.

The theory works, and until we have a better understanding of the universe as a whole to give a better idea of where everything came from other than "it just phased into being" and where the laws of nature came from and time, the big bang theory is the best we have.

Drakkith

The big bang theory does not go back to the beginning of the universe. It makes no claims on where the universe originated from, it only says that the universe expanded from a very hot dense state and describes the universe from then on.

Anddy002

bcrowell: As I completed the thread I did not get the explanation over the statement that the “older than your mama-concept” was solved? It seems to me that you just avoid giving any kind of explanation or hint to that fact…

DNMock

What?

The official name isn't "The Big Bang Theory" it is "The Big Bang Theory for the Origin of the Universe"

http://www.rsc.org/chemsoc/timeline/pages/1927.html

Here is a bit from NASA: "The Big Bang Model is a broadly accepted theory for the origin and evolution of our universe."

http://map.gsfc.nasa.gov/universe/bb_theory.html

According to the Big Bang model, the universe did not exist before the big bang because the big bang created time and space, therefor there was no time, nor space prior to the big bang for it to exist in.

Drakkith

What I mean DNMock is that the model of the theory only describes the universe from a point in time greater than about 10^-43 seconds. Before that the model cannot make predictions about the state of the universe. Of course, that point in time is so close to the beginning I guess you could say that it might as well be the beginning. What happened at t=0 or possibly before if possible cannot be described by the standard model, however we do have new theories being developed that do make those predictions.

Chalnoth

Read a little bit more carefully. See the following sentence:
Note that it does not say that our universe was a singularity. This is good. If it did say that, I would be right now firing off an angrily-worded e-mail to NASA saying that their website was inaccurate and misleading. So it doesn't describe the absolute beginning, but it does describe our universe starting from a very early time.

cephron

Hi Chalnoth, I was reading one of the other threads and ended up looking at the FAQ:
http://www.physicsforums.com/showthread.php?t=506992
(About why the universe didn't collapse into a black hole)

Near the end, it says:
Does this part need to be updated? Or is it somehow talking about something else/a different kind of singularity?

Chalnoth

That singularity exists in the math, but cannot be real. Basically, the singularity is a prediction of General Relativity, but to describe densities approaching the singularity we would need a theory of quantum gravity, which we don't have. It's therefore a nonsense prediction: General Relativity simply isn't valid in that regime.

cephron

Ah, that makes sense. Thanks.

HallsofIvy

You started off telling us that you are a freshman in highschool. Now, you tell us that you have "beliefs" that you are certain are true no matter what educated scientists and experiments say to the contrary. And then you talk about "religious belief" of scientists? So, to you "religious beliefs" are those that are based on experimental evidence while your own beliefs are based on what?

Sounds to me like you really don't want to be a scientist. Or, if you think you do, it's only because you have no idea what science is.

Tanelorn

Well I dont actually "believe" in anything these days, but it is a fact that The Big Bang model is the prevailing cosmological theory of the early development of the universe.


Also for evidence we have:

The earliest and most direct kinds of observational evidence are the Hubble-type expansion seen in the redshifts of galaxies, the detailed measurements of the cosmic microwave background, the abundance of light elements (see Big Bang nucleosynthesis), and today also the large scale distribution and apparent evolution of galaxies[47] which are predicted to occur due to gravitational growth of structure in the standard theory. These are sometimes called "the four pillars of the Big Bang theory"


I am wondering if belief is the right word for the original question or the replies.

zonde

There is nothing wrong with that. You have to start somewhere.

You can't do that. At least using scientific method. You can't even disprove Big Bang model as one can always update model in the light of new evidence. Actually this is part of science.

If that was not so this one observation would have disproved Big Bang:
On time dilation in quasar light curves

But what you can actually do is propose model that explains observations better that existing model and makes better predictions about possible future observations.

The thing about scientific method is that it does not allow you to prove theory but only to separate poor theories from good theories.

I like this quote that is given in wikipedia under article about Empiricism:

zahero_2007

No , big bang is wrong because it asserts our universe arose from a singularity which is wrong , Instead colliding branes models avoids the initial singularity .

Chalnoth

That's the entirely wrong way to look at things. The Big Bang Theory is a highly accurate description of our universe back to very early times. While it does make some statements about what happened even earlier, those statements are nonsensical and the theory cannot be taken seriously in that regime.

There are many ideas for what happened in that regime. Colliding branes is one of them. It is absolutely not the only way to avoid the initial singularity. At present, what went on in that regime is mostly speculation, though we do have some limited evidence.