According to the current cosmological theories, it's the model that explains the early life of the universe, starting from a rapid expansion of hot and dense matter.
5
votes
4answers
843 views
Did spacetime start with the Big bang?
Did spacetime start with the Big Bang? I mean, was there any presence of this spacetime we are experiencing now before big bang? And could there be a presence/existence of any other space-time before ...
5
votes
5answers
1k views
Conservation law of energy and Big Bang?
Did the law of conservation of energy apply to the earliest moments of the Big Bang? If so, what theoretical physics supports this?
I hear that Einstein's theory of relativity disputes the law of ...
8
votes
3answers
1k views
What has been proved about the big bang, and what has not?
Ok so the universe is in constant expansion, that has been proven, right? And that means that it was smaller in the past.. But what's the smallest size we can be sure the universe has ever had?
I ...
5
votes
1answer
585 views
on causality and The Big Bang Theory
With the notion of causality, firmly fixed by GR, we derived the concept of a singular point from where space-time begun. Causality alone gives us the possibility to talk about a known past (i.e. ...
2
votes
9answers
686 views
understanding time: Is time simply the rate change?
Is time simply the rate of change?
If this is the case and time was created during the big bang would it be the case that the closer you get to the start of the big bang the "slower" things change ...
1
vote
1answer
217 views
spacetime expansion and universe expansion?
First of all, does the expansion of spacetime solely cause the expansion of universe?
Secondly, if spacetime is the sole cause, do objects(matter with mass) themselves expand?
Thirdly, by spacetime ...
3
votes
4answers
361 views
Origins of the universe questions
If the universe is expanding, what is it expanding into?
Similarly when the big bang happened where and how did it occur? - Where did the energy come from? Energy can not be created or destroyed does ...
7
votes
4answers
1k views
Did time exist before the creation of matter in the universe?
Does time stretch all the way back for infinity or was there a point when time appears to start in the universe?
I remember reading long ago somewhere that according to one theory time began shortly ...
5
votes
3answers
445 views
How can a quasar be 29 billion light-years away from Earth if Big Bang happened only 13.8 billion years ago?
I was reading through the Wikipedia article on Quasars and came across the fact that the most distant Quasar is 29 Billion Light years. This is what the article exactly says
The highest redshift ...
5
votes
4answers
1k views
What is our location relative to the Big Bang?
Given what we know about space, time and the movement of galaxies, have we or can we determine what our position is in relation to the projected location of the Big Bang? I've read some introductory ...
1
vote
1answer
242 views
Superluminal expansion of the early universe how is this possible?
Is this a postulate? I get the expansion of the universe, the addition of discrete bits of space time between me and a distant galaxy, until very distant parts of the universe are moving relative to ...
3
votes
4answers
288 views
Before the Big Bang
I've heard this saying before I don't know about anyone else. It says, "What ever was before the big bang is something physics can't explain..!
Is this saying true (accurate)?
12
votes
6answers
676 views
How can it be that the beginning universe had a high temperature and a low entropy at the same time?
The Big Bang theory assumes that our universe started from a very/infinitely dense and extremely/infinitely hot state. But on the other side, it is often claimed that our universe must have been ...
4
votes
5answers
3k views
How can something happen when time does not exist?
I saw this documentary hosted by Stephen Hawkins: www.youtube.com/watch?v=WQhd05ZVYWg
And if I didn't get it wrong, it says that there was no time before the big bang, time was created there.
So how ...
5
votes
5answers
2k views
Why was the universe in a extraordinarily low-entropy state right after the big bang?
Let me start by saying that I have no scientific background whatsoever. I am very interested in science though and I'm currently enjoying Brian Greene's The Fabric of the Cosmos. I'm at chapter 7 and ...
9
votes
2answers
514 views
Why can we see the cosmic microwave background (CMB)?
I understand that we can never see much farther than the farthest galaxies we have observed. This is because, before the first galaxies formed, the universe was opaque--it was a soup of subatomic ...
6
votes
4answers
413 views
Big Bang snuffed by a black hole?
Wasn't the density of the universe at the moment after the Big Bang so great as to create a black hole? If the answer is that the universe/space-time can expand anyway what does it imply about what ...
5
votes
1answer
1k views
How can something finite become infinite?
How can the universe become infinite in spatial extent if it started as a singularity, wouldn't it take infinite time to expand into an infinite universe?
3
votes
3answers
202 views
Can space expand with unlimited speed?
At the beginning, right after the Big Bang, the universe was the size of a coin. One millionth of a second after the universe was the size of the Solar System (acording to ...
3
votes
2answers
354 views
Is the observable universe enclosed by an infinitely dense shell?
In modern cosmology, it is commonly stated to the public that as we look deeper and deeper into space, we are seeing further into the past. CMB is the relic of the big bang after photon decoupling ...
1
vote
1answer
226 views
Is it possible that the Big Bang was caused by virtual particle creation?
As far as I understand, it is understood that throughout the universe there exists, what is known as, a quantum field from which, due to its fluctuations, temporary (pairs of) virtual particles ...
13
votes
4answers
346 views
Does the universe have a center?
If the big bang was the birth of everything, and the big bang was an event in the sense that it had a location and a time (time 0), wouldn't that mean that our universe has a center?
Where was the ...
5
votes
2answers
109 views
Is there a consensus on the fate of our universe?
We all know that our universe is inflating from what is known as the Big Bang. However, will our universe continue to inflate at the current rate? Or after reaching a maximum size, will it collapse in ...
3
votes
2answers
205 views
Big Bang and Cosmic microwave background radiation?
One of the experimental evidence that supports the theory of big bang is cosmic microwave background radiation (CMBR). From what I've read is that CMBR is the left over radiation from an early stage ...
2
votes
3answers
369 views
Does (it make sense to say that ) the universe has a center?
I was reading this page:
http://www.guardian.co.uk/science/2011/oct/23/brian-cox-jeff-forshaw-answers
and I found this sentence by Brian Cox:
That seems to imply that everything is flying away ...
1
vote
2answers
127 views
What's the evidence supporting 1 singular Big Bang? [duplicate]
Possible Duplicate:
What has been proved about the big bang, and what has not?
I love to dabble with science, I'm by no means a scolar in this field. One thing that haven't seen proven yet ...
1
vote
1answer
2k views
Negative and positive energy and Hawking [closed]
I don't have any physics background (except the material we did in high school-long time ago).
I was watching a documentary with Stephen Hawking about whether God created the Universe and I could not ...
6
votes
1answer
453 views
Alternative theories to the big bang?
Hey all, are there any theories out there on the origins (or infinite existence of) the universe beside the big bang that actually adhere to current scientific knowledge and fact?
5
votes
3answers
215 views
Is the cosmic horizon related to the Big Bang event?
The Universe expands according to the Hubble's law: velocity is proportional to distance.
There must be some distance, therefore, at which the velocity reaches the speed of light. This defines the ...
2
votes
2answers
430 views
Big bang and time
I heard Carl Sagan talking about the Universe 15 Billion years ago, and the Big Bang. He made the statement that it was the biggest explosion of all time (at first I thought this a subtle pun). This ...
1
vote
1answer
343 views
Universe Expansion as an absolute time reference
Why we call "constant" to the Hubble constant?,
if the universe were really expanding then the Hubble "constant" should change, being variable, smaller and smaller..with "time".
Other example/view ...
10
votes
5answers
107 views
How large is the universe?
We know that the age of the universe (or, at least the time since the Big Bang) is roughly 13.75 billion years. I have heard that the size of the universe is much larger than what we can see, in other ...
7
votes
2answers
132 views
Is it possible to look into the beginning of the Universe?
If we currently can look into some of the furthest stars, actually seeing the past
Isn't it conceivable that given enough distance we should be able to see
Parts of the Big Bang? If the Universe is ...
1
vote
0answers
46 views
Is the speed of light the ultimate speed limit? [duplicate]
As we all know nothing can go faster than the speed of light as mentioned by most of our pioneer's in physics. But as I was listening to one of the statements of Sir. Stephen Hawkins he stated that at ...
1
vote
1answer
159 views
Are there any theories or suggestions for how the multiverse came into existence?
I've just seen a documentary about the multiverse. This provides an explanation for where the big bang came from. But it leaves me wondering: how did the multiverse come into existence?
Because this ...
1
vote
4answers
536 views
Atoms pop out of nothing/vacuum/pre-big-bang?
I saw a great documentary last night about 'nothing'. It's about vacuums, and how if you have a total vacuum atoms will pop out of nowhere! Pretty crazy stuff. Atoms literally coming out of ...
1
vote
2answers
226 views
Primordial Black Hole Detection
There's ample direct evidence for the existence of galactic and stellar mass black holes. However, there is no such direct evidence of primordial black holes, those formed after the Big Bang. A recent ...
1
vote
1answer
440 views
Has Cosmological Natural Selection been disproved?
I've been reading Lee Smolin's Life of the Cosmos.
Great book and it makes a lot of sense that the conditions in black holes are the same as conditions at the big bang.
Question is, has his theory ...
1
vote
1answer
376 views
How to calculate the density of relic neutrinos?
May be not neutrinos, but antineutrinos? Or both types?
In the last case, why they didn't annihilate and what is the ratio of relic neutrinos to relic antineutrinos? Is that ratio somehow related to ...
0
votes
1answer
147 views
Did space and time exist before the Big Bang? [duplicate]
I accept the Big Bang theory. What I can't understand is how there can be a where or when to the Big Bang if space time did not exist prior to it. Did space and time exist prior to the Big Bang?
0
votes
1answer
52 views
Can anything come out from the big bang?
If any configuration of matter can fall into a black hole and hit the singularity, and ditto for the big crunch, and there is time reversal CPT invariance, does it mean anything can pop out of the ...
0
votes
2answers
159 views
Big Bang Anybody? [duplicate]
Possible Duplicate:
Did time exist before the creation of matter in the universe?
on causality and The Big Bang Theory
I was recently watching a Discovery special on the Big Bang theory, ...
0
votes
2answers
290 views
Does the Big Bang need a cause? [duplicate]
Possible Duplicate:
on causality and The Big Bang Theory
Asking here in layman's terms..
When theoretical physicsists discuss the origin of our Universe, the wider consensus appears to be ...
0
votes
0answers
429 views
Was the Big Bang a result of a decayed white hole singularity? [closed]
From my understanding, the Big Bang is theorized to have been a result of matter ejecting from a decayed white hole space/time singularity.
...
