
To have an enjoyable cosmo forum we needed a balance between mental freedom on the one hand and a shared knowledge...

Aug214 07:51 PM
marcus

493 
167,538 
The new A20 tabular calculator lets you look at changing geometry out to about 88 billion years according to the...

Jun1114 11:00 AM
Jorrie

65 
45,796 
For scalar modes \mathcal{R}_k originating in the BunchDavies vacuum at the onset of inflation, I have the following...

T 05:26 PM
thecommexokid

0 
53 
Can someone please explain to me why the universe must be expanding and not contracting? Here is my take on this.
...

T 03:12 PM
Bandersnatch

6 
117 
I love having discussions with my friends about cosmology, physics and just the universe is general but can someone...

T 10:51 AM
0zyzzyz0

13 
386 
Hi Guys,
I have just started Modern Cosmology and please don't mind if the question is too naive.
I wanted to...

T 05:30 AM
craigi

1 
168 
So the universe starts with an amount of matter, radiation, a fixed spatial curvature constant and a cosmic constant....

T 02:09 AM
Lapidus

14 
386 
If the bulk universe is infinite (IF it is), would mathematical physics have trouble describing it because infinity is...

Y 11:31 PM
Chalnoth

6 
293 
Hi Guys,
Can anyone provide links, books which explain the mathematical background of the field theory that...

Y 09:48 AM
Chalnoth

1 
210 
Please, can anyone help to analyse fluctuations of density in De Sitter Space in case of long waves?
Formulas and...

Sep1214 07:29 AM
bapowell

1 
163 
A couple of questions came up from different people and I thought I'd respond here in case anyone else might be...

Sep1214 06:56 AM
Jorrie

14 
372 
I’m learning about cosmology and I’m struggling understanding the size and shape of the universe.
If the universe...

Sep1214 04:20 AM
Chronos

8 
438 
http://physicsworld.com/cws/article/news/2014/sep/02/bigbangruledoutasoriginoflithium6
The hystory of BB...

Sep1114 03:24 PM
TrickyDicky

4 
278 
Planck dust modeling has been released http://arxiv.org/abs/1409.2495]. It appears to be consistent with the...

Sep1114 04:37 AM
Garth

1 
280 
Hi everyone. I'm new to this forum...I just wanna make it clear that I'm an engineering student, thus I don't wanna...

Sep1114 03:21 AM
Domenico94

10 
387 
say you fell beyond the event horizon of a black hole can another black hole passing close enough pull you out?

Sep1114 12:01 AM
PeterDonis

20 
580 
Hello Everyone,
This is my first post, I hope I've picked the right forum for this question.
Could a black hole...

Sep1014 11:15 PM
Nugatory

6 
262 
Forgive me if this is a foolish question but, what caused the super force in the early universe to split into the weak...

Sep1014 04:49 PM
Chalnoth

9 
494 
Has anyone here ever asked these questions about the balloon analogy?
1. If the universe actually was the 3D...

Sep914 03:34 PM
Drakkith

34 
676 
Could the universe be expanding wave fronts and the fundamental particles of matter be the particle manifestation of...

Sep914 02:11 AM
Chalnoth

2 
249 
So the universe is expanding, rather space is expanding. By expanding we mean space is coming into existence at all...

Sep814 10:30 PM
PeterDonis

7 
295 
Conventional Cosmology would explain greater than c recessional velocities of the nebula as a nonproblem regarding...

Sep814 02:35 PM
PeterDonis

14 
739 
I originally posted a thread regarding desitter spaces, Poincare recurrence theorem, and statistics. My main...

Sep814 02:04 AM
Chalnoth

1 
188 
I am currently reading "Our Mathematical Universe" by Max Tegmark. From the book I learned a couple of things I find...

Sep814 01:59 AM
Chalnoth

9 
312 
I've seen the example when people say the universe is expanding like the surface of a balloon. You have dots on that...

Sep714 06:18 PM
Drakkith

6 
336 
The multiverse is a theory that the are countless universes.
What is the evidence for the existence of the...

Sep714 03:04 AM
julcab12

39 
1,573 
Is Supersymmetry still viable in cosmology, given that so far no supersymmetric particles have been found.
From...

Sep614 04:19 PM
Chalnoth

6 
310 
The Big Bang is often associated with the concept of a singularity. A singularity is defined as a point in spacetime....

Sep614 08:31 AM
Incnis Mrsi

5 
572 
I've been working with NFW Dark Matter Halos recently. This is a particular density model for the halo developed by...

Sep514 10:36 AM
phyzguy

3 
191 
I am curious to know if it is theoretically possible for the origin of the Big Bang to have been the energy released...

Sep414 04:46 PM
PeterDonis

13 
490 
I am at the lowest level of the spectrum when it comes to this subject, but this has always raised some questions for...

Sep414 06:27 AM
Bandersnatch

2 
276 
Do white dwarf planets ever die and eventually there will be no remains of the sun? What will happen to the gas giants...

Sep214 01:22 PM
Drakkith

17 
916 
This paper; http://arxiv.org/abs/1408.6248, Constraints on gravity and dark energy from the pairwise kinematic...

Aug2914 04:37 AM
enorbet

1 
359 
Recently reading the Scientific American article The Black Hole at the Beginning of Time, which at first glance made...

Aug2914 04:14 AM
enorbet

5 
388 
Just been looking around for any good resources or databases which show history of stars in the universe. I have...

Aug2814 03:05 AM
nick1o2

4 
408 
Is it possible that our universe is just one of more universes and that our universe just appears to be expanding...

Aug2714 04:44 PM
mfb

5 
532 
hey all! I have just finished processing the data of an nbody simulation (RAMSES code was used to do the simulation...

Aug2714 03:57 PM
Greg Bernhardt

1 
478 
All  my first post, and as a lay person interested in quantum physics, forgive me if my questions are naive or...

Aug2714 04:18 AM
phinds

9 
431 
Brown dwarf galaxies are, i think the coldest systems in the universe, If they continue to loose heat energy they must...

Aug2714 03:02 AM
Chronos

4 
424 
We know that a photon has no mass, but has relativistic mass  which means in theory, a photon will have a...

Aug2714 12:10 AM
Chalnoth

2 
404 
I ran a search and didn't see anything posted recently, at least, on the current thoughts behind the zeroenergy...

Aug2614 09:58 AM
PeterDonis

3 
494 
I've always been curious about about the big bang because (from what I've read) it's a point we're not able predict...

Aug2514 01:49 PM
Drakkith

7 
519 