Big bang Definition and 916 Threads

How can the elapsed time from the big bang be known if it isn't known how far the universe extends past the ability to observe it? In other words, would a larger universe take longer to contract towards a singularity? Or, if the universe were infinitely large how could it have expanded from...

I have read several times that many are unhappy with the name "The Big Bang". Some say that it is misleading to those trying to learn what it means, and others say that it is at least memorable. So I wondered if there are any better alternative names out there?

This is not a pro creationism question. I can see where people are coming from with it but there is so much that it doesn't cover or explain but it is treated like the holy grail of "where the universe comes from" ideas/theories. I have nothing against Dr. Hawking by any means but something...

The Big Bang is seen by Alan Guth as having been produced by a relatively short burst of negative pressure, as a result of a high energy state that is temporarily trapped on some sort of non-zero plateau in the vacuum. I have a quote here from a popular science book by Green to clarify things...

In "Big Bang Theory" (the show) what are their jobs?Serious Seriously, they're clearly not post-docs and they're clearly not professors. What job is there for a physicist at a university beyond that?

Ive heard that soon after the big bang matter and antimatter was created in equal proportions and that majority of the matter-antimatter annihilated among each other, somehow only a small fraction of matter remained... my question is... what was the form of the matter or antimatter which was...

I know that there is by no means a definitive answer to this question, but, could someone list all the major current theories for what caused the big bang please? Thank you

I've been looking for more information about the state of matter [or soon to be matter] shortly after the big bang. As time progressed after the big bang matter started to develop and it became more and more complex and massive [for the most part], we had quarks then protons then neutrons then...

What was there before Big Bang? Cosmologists suggested that there was quantum vacuum, but what was there before quantum vacuum? From where did quantum vacuum came? And why was there a quantum vacuum rather than nothing?

posted this back in 2010 elsewhere Now It's a question that's been irking me for a while, I asked here once and never got an answer. Just a question of simple logic.. I take two points in space that are astronomically distant. Important that I Choose 2 stars. "Frebel has found...

I've read a fair few articles recently about the big bang being utter fiction and that there is ALOT more evidence to disprove it than to prove it. Obviously it could never be entirely proved but to my mind the evidence against it should be enough to disprove it. Do we just stick to the big bang...

Is it possible that whatever cause the big bang to happen and make space expand also (for lack of a better phrase) tore time in two? Resulting in two universes moving in opposite directions of time, and could this be used to explain why there appears to be more matter then antimatter in the...

I was watching 'Into the Universe, with Stephen Hawking', and it said that once the big bang began, in a few minutes the universe was the size of a galaxy. Einstein said that nothing could travel faster than the speed of light, if so, how did the big bang expand that fast?

Will the big bang be seen as 13.7 billion years ago by all observers in the universe regardless of their velocities ? I mean I read that in SR one has to abandon notions of simultaniety. And an event which has already occurred for one observer may be in future for another observer. I guess...

FAQ: What is the evidence on Big Bang versus steady state cosmologies? Let's consider this question first under the assumption that general relativity and standard quantum mechanics are valid. (Both QM and GR have been verified to high precision by a wide variety of empirical tests.[Will])...

Either the Big Bang began in a small, restricted area/volume/domain/node/etc or the universe sprang into existence "everywhere all at once" -whatever that means- as I once read somewhere (to explain why the universe has no center). So which is it? And if it sprang into existence in a homogenous...

Hey guys, I'm deeply interested in physics and I want to be a theoretical physicist, I'm only freshman in high school, but I'm in 2nd quarter calculus. I've a question that want to ask. I've read many article about physics especially SR and GR, could it be that redshift that we see from moving...

Hi there PF I know this is rather unorthodox, but I have been watching the science-fiction series Eureka for a while now, and in the latest episode I have seen, there was a device, that would recreate the Big Bang itself. The episode I am speaking of is episode 8 in season 2 (link to episode...

I've read that theorists predicted the big bang to expand faster than the speed of light. Is this true? If so, how can we say that nothing can travel faster than light today?

The following started to puzzle me: I heard George Smoot talk on design of the universe. He made the point that when we look far into the space, to distant galaxies, we see these galaxies "happening" really long time ago, since the speed of light is what it is. That the universe we are...

If there were no Space-Time before the Big Bang, then where did that explosion took placed?

You can probably tell from my terminology that I am not a scientist, but I have a vision of the Big Bang that I have tried to summarise below (I will spare you the detail!). Could some kind cosmologist out there please tell me whether or not my vision reflects any main stream scientific...

OK the question is this. if we say the big bang big crunch module is true and entropy increases over time is there a set law to say it won't increase to the end of the big crunch, and if it dose will it affect the next big bang, if so could this be the only or last big bang that contained life...

triggering the big bang! if we consider singularity as the starting point of our universe...what could have possibly triggered the big bang?

Are any ideas out there on the possibility of a Black Hole being a wormhole(?) to another dimension/universe and if so, could the matter that's pulled in through a Black Hole be the same matter that births a Big Bang on the other side of the Black Hole? Maybe a better question is do we have...

All the matter and engery making up the Universe could not up just appeared at a 'singularity' out of nowhere. It must have existed before the BB in a different format. Can anyone recommend a list of good books which explores this topic?

I understand that the quantum vacuum is nothing with particles popping into and out of existence and I also understand that this has been in existence since the big bang but I am curious as to whether this type of nothing could exist before the big bang (not relying on a multiverse). I assume it...

I understand that the standard cosmological model says that as one goes back in time towards the big bang the Universe is radiation-dominated. This means that the mass/energy density, rho, in the universe is given by the Stephan Boltzmann law: rho = T^4 where T is the temperature of radiation...

Just wanted to say the new Family Guy episode is brilliant! Episode is called The Big Bang Theory, even if you don't like family guy this episode is going to become a classic for anyone even remotely bothered about science. Watch It! Chris

Anyone familiar with both quantum mechanics and cosmology here. Say. How much dynamics can occur in the deterministic Schroedinger Equation in its evolution while it is in unitary state (before collapse)? For example. Is it possible for the Big Bang and evolution of stars to solar system and...

Before the big bang the entire universe was squeezed down into an incredibly hot and small ball. If so much matter is squeezed down into such a small space it will become a black hole. Nothing can escape the gravitational pull of a black hole, so how did this tiny universe before the big bang...

Why didn't the big bang just become a black hole? Thanks, Jake

When physicist talk about time after the big bang, what do they mean? Time is relative, so which frame of reference are they talking about? Could anyone please explain?

I'm in full agreement with a Big Bang start of our Universe. However, I am a little perplexed as to where these staring materials originated from. Now, I know that there is no solid answer, but I was just curious as to some theories. Thanks.

Hey guys. I was looking at the Robertson - Walker metric and went about calculating R^{\mu \nu }R_{\mu \nu } as a way of looking at coordinate independent curvature properties through the Ricci Tensor. Considering I did it correctly I ended up with: R^{\mu \nu }R_{\mu \nu } =...

Has anyone yet asked a computer to calculate the chance of a Big Bang eventually forming thinking modern humans (e.g. Big Bang produces Brian Cox) purely by natural process and without some programme to channel things? If so, can anyone tell me (even approximately) what the result of this...

I have seen in many books explaining big bang the following kind of expressions.. “In the first few seconds of big bang…” “In the first few millionth of seconds of big bang..” Since time is not absolute, what exactly is meant by these “seconds”? Are these seconds same as “our second”...

Time and "Before" the Big Bang I am just trying to get a feel for the general consensus on whether not not time was "created" in the Big Bang, meaning there really is no "before" the Big Bang. As I understand it, in M Theory cosmology the (or, our) Big Bang would not be the beginning of...

How big is the initial size of the Big Bang... inside a Planck length? Can it fit inside? Or as big as an egg? Or a kilometer?

just to interesting not to share. http://bit.ly/g6sFMh i posted a question there which i wish to post also here, and get some insight. why is this CMB uniform and dark energy and/or dark matter so uniformly spread and are not directly related? i.e. why aren't we saying that the CMB is emitted...

Source: http://www.indystar.com/article/20110320/LOCAL01/103200369 http://www.dailymail.co.uk/news/article-1369595/Jacob-Barnett-12-higher-IQ-Einstein-develops-theory-relativity.html Thoughts?

The LHC is supposed to create conditions similar to the big bang. Although energy densities, temperatures and other conditions may be similar to those theorized in the big bang and soon thereafter, are the conditions of space and time the same now as then? If time and or space were fundamentally...

You know how the lambda constant just grew exponentially in the first second of the universe? That was just a temporary thing right?

How was the big bang possible considering the 1st law of thermodynamics. Was all energy and matter created during the big bang or was it previously somewhere else? has the energy and matter from the big bang existed forever?

I don't know much about the big bang but if there was an explosion and the universe started expanding from a small region how could it expand at all the Gravitational field would be immense. If all our energy in the universe today was put into a small region it would be like a black hole and...

What caused and is causing space to increase or expand? Greetings, The answer to a major question has raised another problem...then solution...then questions. Why didn't gravity keep everything together at the big bang like a black hole? Because *all* of space was filled with...

Greetings, #1 - If all matter energy, and space were concentrated at the big bang, and the universe has been expanding at a finite rate, then why is anything other than a finite universe considered? http://en.wikipedia.org/wiki/Shape_of_the_Universe #2 - Also, as discussed in another...

Hi everyone. Can anyone help with this thought. What was the quantum state at t=0 or at the big bang. I thank you very much for your help. TheNaturalist

Hi, I was just pondering the moment of the Big Bang, and have been doing some reading on the subject, in which there exists problems consolidating the mathematics of relativity and quantum mechanics. To my understanding the theory of realtivity predicts the universe started from the Big Bang...

We know that matters cannot escape from the gravity of a black hole when they are close enough to its center. Would it be the same at the start of the big bang? Why matters can escape from the huge gravity at the start of the big bang?