The Origin of the Universe: Unraveling the Mystery of the Big Bang

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In summary, the conversation is discussing the origins of the universe, specifically the question of where the original components came from. The Big Bang theory states that there was a singularity from which the universe was born, but it does not explain where this singularity came from. The concept of conservation of energy is brought up, but the total energy of the universe is estimated to be zero, with positive matter and negative gravity balancing each other. This means that no energy was needed to produce the universe and the first law of thermodynamics was not violated. The conversation also discusses the idea of a creator and the concept of chaos or nothingness before the big bang.
  • #1
Jordan Joab
I've been watching documentaries and programs related to the Universe and its origins. That made me curious and I began reading/researching more about this topic. All sources do a good job of explaining everything back to the point of origin. However, there's something that no one seems to be explaining: where exactly did the original components come from?

I'll use the Big Bang model to explain myself. The Big Bang theory states that there existed a "singularity" from where the Universe we study 13 billions years later was born. Alright, where exactly did this "singularity" originally come from? How would the Conservation of Energy Law explain this (if I am understanding it correctly)?

This is how I picture it: nothing -> singularity -> Big Bang -> Universe. It feels as if the Big Bang theory wants me to accept that this singularity has always existed yet everything in the Universe displays a cycle of "life and death."

When my brain tries to interpret Big Bang in basic mathematical terms it looks something like this: 0 = 1. Basically, nothing = something or from nothing came something.

In conclusion, what I'm understanding is that energy created itself out of nothing; everything we know today suddenly materialized out of absolute emptiness. What am I missing here?



Jordan Joab.
 
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  • #2
Actually, the modern Big Bang Theory says no such thing. It says that the universe was smaller, hotter and denser in the past, which is around 13.7 billion years ago. The Big Bang Theory describes the development of the universe, not its origin.

http://books.nap.edu/openbook.php?isbn=0309064066&page=2

A scientific theory is a well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses, not a random guess.

"There are something like ten million million million million million million million million million million million million million million (1 with eighty zeros after it) particles in the region of the universe that we can observe. Where did they all come from? The answer is that, in quantum theory, particles can be created out of energy in the form of particle/antiparticle parts. But that just raises the question of where the energy came from. The answer is that the total energy of the universe is exactly zero. The matter in the universe is made out of positive energy. However, the matter is all attracting itself by gravity. Two pieces of matter that are close to each other have less energy than the same two pieces a long way apart, because you have to expend energy to separate them against the gravitational force that is pulling them together. Thus in a sense, the gravitational field has negative energy. In the case of a universe that is approximately uniform in space, one can show that this negative gravitational energy exactly cancels the positive energy represented by the matter. So the total energy of the universe is zero. Now twice zero is also zero. Thus the universe can double the amount of positive matter energy and also double the negative gravitational energy without violation of the conservation of energy. (Hawking, Stephen, "Brief History of Time", 1998, pp. 133-134)

Intelligent Design: Humans, Cockroaches, and the Laws of Physics

"However, our best estimate today is that the total energy of the universe is zero (within a small zero point energy that results from quantum fluctuations), with the positive energy of matter balanced by the negative potential energy of gravity. Since the total energy is zero, no energy was needed to produce the universe and the first law was not violated.

The second law of thermodynamics requires that the entropy, or disorder, of the universe must increase or at least stay constant with time. This would seem to imply that the universe started out in a greater state of order than it has today, and so must have been designed.

However, this argument holds only for a universe of constant volume. The maximum entropy of any object is that of a black hole of the same volume. In an expanding universe, the maximum allowable entropy of the universe is continually increasing, allowing more and more room for order to form as time goes by. If we extrapolate the big bang back to the earliest definable time, the so-called Planck time (10-^43 second), we find that universe started out in a condition of maximum entropy - total chaos. The universe had no order at the earliest definable instant. If there was a creator, it had nothing to create.

Note also that one cannot ask, much less answer, "What happened before the big bang?" Since no time earlier than the Planck time can be logically defined, the whole notion of time before the big bang is meaningless.
 
  • #3
However, our best estimate today is that the total energy of the universe is zero (within a small zero point energy that results from quantum fluctuations), with the positive energy of matter balanced by the negative potential energy of gravity. Since the total energy is zero, no energy was needed to produce the universe and the first law was not violated.

No energy was needed to produce the Universe because positive matter and negative gravity balanced each other. How did matter and gravity come to be? How did they obtain their positive/negative energy?

However, this argument holds only for a universe of constant volume. The maximum entropy of any object is that of a black hole of the same volume. In an expanding universe, the maximum allowable entropy of the universe is continually increasing, allowing more and more room for order to form as time goes by. If we extrapolate the big bang back to the earliest definable time, the so-called Planck time (10-43 second), we find that universe started out in a condition of maximum entropy -- total chaos. The universe had no order at the earliest definable instant. If there was a creator, it had nothing to create.

If I'm understanding this paragraph correctly, the word "chaos" means "emptiness or nothing." In other words, when a system is at maximum entropy/disorder there's simply nothing there - total emptiness. Do we consider nothing to be a "disordered" state?

Note also that one cannot ask, much less answer, "What happened before the big bang?" Since no time earlier than the Planck time can be logically defined, the whole notion of time before the big bang is meaningless.

And to me this is the most important aspect. Saying that "the whole notion of time before the big bang is meaningless" is the same as saying that "God is the creator." Neither can be logically explained yet we don't have sufficient proof to confirm their existence or non-existence.

Is like we either try to accept that things have always existed or that they were formed out of a "nothing" that our brain might not even be wired to understand. So, beyond assigning a mathematical value and trying to figure out how things came to be at the start of Planck time, seems we are not bothering with finding out how and what exactly happened a second before "something came out of nothing."



Jordan Joab.
 
  • #4
Ultimately, our notion of cause and effect does not allow us to answer this question about how something can come from nothing. We think, something must have caused the beginning of everything, but what then caused that something? There is an error in our logic.
 
  • #5
Science has nothing to say about what preceded the BB; that's for the Philosophy forum.
 
  • #6
I'm partial to a creation event - 'Let there be light'. It's effective and difficult to disprove. It also explains why math and science struggle to offer alternative explanations.
 
  • #7
A creation events offers no explanation, because such an hypothesis cannot account for what methods or mechanisms was used, the identity of the creator or how it was created. It seems to be a non-answer, at least so far.

I do not think our ignorance or struggles can be used as evidence of something supernatural. When we did not know what caused disease, we were not justified by this ignorance to come to the conclusion that witches caused them.

Asking what happened "before" the BB is like asking what is north of the north pole. The question itself is not meaningful. One could argue that the term "nothing" is also meaningless, which would make the question of "why is there something, rather than nothing?" or "how can something come from nothing" also meaningless.
 
  • #8
Well, a creation event and a BB event share the same problem presented by this topic but I think is not convenient for the creation event to answer this question since it would have to explain how this creator became so powerful. Let's stick to science.

What irks me about these programs and documentaries shown on History, Discovery, etc. is that they tell you about big bang but don't even bother to address the question that's hitting me right in the face: where did that singularity come from?!

That energy had to be created somehow.



Jordan Joab.
 
  • #9
There was no singularity. Singularities are merely artifacts of our models. The first law of thermodynamics tells us that energy can neither be created or destroyed. I do not see how a net sum of zero needs to come from something? Sure, if there was an excess amount of energy that could not be accounted for, cosmology would have a much larger problem in explaining things.
 
  • #10
Jordan Joab said:
Well, a creation event and a BB event share the same problem presented by this topic but I think is not convenient for the creation event to answer this question since it would have to explain how this creator became so powerful. Let's stick to science.

What irks me about these programs and documentaries shown on History, Discovery, etc. is that they tell you about big bang but don't even bother to address the question that's hitting me right in the face: where did that singularity come from?!

That energy had to be created somehow.



Jordan Joab.

These programs are geared towards the average joe with a curiosity about cosmology. The question of where the singularity possibly came from (thus the origin of the universe) is pretty much metaphysics. You can look at M-Theory if you want, but it's basically just a really elegant way of saying "it happened". Not to mention the mathematics of any particular model quickly become overwhelming to anyone without a PhD in the field. The point is, if you want to do some serious cosmological learning, do not hope to do so from programs on the Discovery Channel and BBC.
 
  • #11
Jordan Joab said:
No energy was needed to produce the Universe because positive matter and negative gravity balanced each other. How did matter and gravity come to be? How did they obtain their positive/negative energy?
If I'm understanding this paragraph correctly, the word "chaos" means "emptiness or nothing." In other words, when a system is at maximum entropy/disorder there's simply nothing there - total emptiness. Do we consider nothing to be a "disordered" state?
And to me this is the most important aspect. Saying that "the whole notion of time before the big bang is meaningless" is the same as saying that "God is the creator." Neither can be logically explained yet we don't have sufficient proof to confirm their existence or non-existence.

Is like we either try to accept that things have always existed or that they were formed out of a "nothing" that our brain might not even be wired to understand. So, beyond assigning a mathematical value and trying to figure out how things came to be at the start of Planck time, seems we are not bothering with finding out how and what exactly happened a second before "something came out of nothing."
Jordan Joab.

Well no, "the whole notion of time before the big bang is meaningless", I think means that if there was no matter, then there was no time because of the general theory of relativity stating that there is no space and time but only spacetime. If there is no matter time can not exist, thus asking what was before time existed is meaningless because you can't explain before without a concept of time and there is no concept of time. Much different then saying "God is the creator". And as far as there is no significant proof that to confirm the existence of nonexistence, you can turn this argument of itself by using a rediculus example.

For example I say that there is an invisible teapot orbiting the moon, and it can not be detected by us in anyway. Can you disprove me? No, of coarse not because I just said you can't detect it and thus there is no observable evidence. Does this mean it's true? Of coarse not. I don't think that you can ever disprove the nonexistence of something, but rather shade in the probabilities of their non existence. I think that with the issue of God, the probabilities of existence are pretty slim, and the only reason null is because you can't disprove it. With the time not existing thing, there are very complicated maths and theories all built upon other theories and evidence, indicated a much more possible scenario, and thus giving evidence to it. Especially with no time= meaningless, this is even more straightforward, it is more like a definition derived from a few simple equations.

So basically a second before nothing doesn't exist, I am less familiar with the explanations of how the first bits of matter did exist ,but I am sure there are some very good explanations, as that Hawkins one above seems interesting and I will look into. Also try to keep in mind, we are humans and our brains are more wired toward things of everyday encounters (i.e. throwing a spear to hunt, running, you know prehistoric things), and that concepts of very large things, especially as the universal level, and very small things at the atomic levels seem unnatural to us because we would never have naturally encountered that, so although it seems mind blowing and unlogical and what have you, by building upon very simple concepts and adding upon our axioms we get the marvelous, complex things we do, and although seem nonintuitive, are infact built upon logic.

By no means does this mean accept nonintuitive things, but try to imagine in the simple steps and that if all of them are logical, then the big step is logical.

Also sorry to get a little bit philosophical, but I felt it was needed, and tbh I felt it was going there anyway =]
 
  • #12
I think Hawking was saying that the original event was just a quantum fluctuation. If so, it was bigger than most, and therefore seems to be insanely improbable. But then we say that the net energy is zero. The length of time that virtual particles can 'borrow' energy is inversely proportional to their energy. So if the cosmic 'seed' particle actually contained zero energy, it would be very probable ... in fact it would be a sure bet. So what is it: insanely improbable or inevitable? If it's zero energy and therefore inevitable, why isn't it happening all the time, or is it? Is there some meta-verse where all this can happen, since our own version of spacetime didn't exist for it to happen into start with?

In conclusion: I think it's okay to say the BB model doesn't need to say anything about what happened before. But humans will always ask this question, and it's not impossible that we will discover that the BB is true, but incomplete. Lisa Randall (if I remember correctly) talks about our spacetime being a 4 dimensional brane floating in a higher dimensional space. BB may have been an event on that brane. Then we ask where that higher dimensional space came from ... and so it goes. Is it all just an infinite regression whose depth will forever remain unplumbed? Maybe that's not a scientific question.
 
  • #13
Moridin said:
Actually, the modern Big Bang Theory says no such thing. It says that the universe was smaller, hotter and denser in the past, which is around 13.7 billion years ago. The Big Bang Theory describes the development of the universe, not its origin.

I agree with what you said here, that I highlighted. It is a good way to put it.

Stephen Hawking wrote his books a long time ago. Nowadays people run their computer models of the universe back before the big bang and do NOT encounter a singularity.
The new models fit the observational data just as well as the old model with the singularity (which is pretty good!)

So the singularity idea may have been a mistake. Strictly from a scientific viewpoint there is no evidence of a beginning of time at some moment 13.7 billion years ago. the evidence is just as good that there was a contraction phase leading to a bounce that occurred at very high density.

If you want to tap into the peer-reviewed scientific publication on this go to Spires and do a keyword search on "quantum cosmology". My impression is that anything you get in the popular media or on television is probably way out of date or worse.

I will try to supply that Spires keyword search link. Here:
http://www.slac.stanford.edu/spires/find/hep/www?rawcmd=FIND+DK+QUANTUM+COSMOLOGY+AND+DATE+%3E+2005&FORMAT=www&SEQUENCE=citecount%28d%29 [Broken]

this is what you get if you go to the Spires database and as for stuff published AFTER 2005 with keywords quantum cosmology.
If you do the same search in earlier time periods like in the 1990s you may get Stephen Hawking or string theory or M theory or whatnot. but this search will get what is recent and also HIGHLY CITED---the output is ranked by how much the papers are referenced in other research
(the sort preference is set to "approx. citation count" so as to list the most-cited papers first)
 
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  • #14
The creation of the universe due to a quantum fluctuation is just one of several theories, not a fact. Since many if not most believe the universe is infinite in size, it can just as easily be infinite in time. Which is to say that it was always here, sometimes very compact before expanding and then contracting again. There is no necessity that it was "created" -- it may just be a human trait to want to assign a beginning since infinity is difficult for our puny minds to conceptualize. Funny thing is, people have no trouble imagining the universe having no end, existing forever, so why does it need a beginning.
 
  • #15
dilletante said:
The creation of the universe due to a quantum fluctuation is just one of several theories, not a fact.

I wasnt talking about the creation of the universe due to a quantum fluctuation. I don't find that approach very appealing, do you? A fluctuation in what?

Papers about that fluctuation story have not been getting very highly cited lately. Not very popular with the experts. Personally I am more interested in what is emerging as the mainstream picture which is just a continued evolution in time.

There is a book called Beyond the Big Bang coming out this year. It can be ordered on Amazon but won't ship until summer. It is for specialists. Written by about 20 experts each doing a chapter. the book explains several possible processes people think could have led up to the big bang. They will have to be compared to observations and tested. It is current research. We don't know.

there will undoubtably be a lot of discussion of this later on when the book comes out. If you want to look at the Amazon page, here it is

https://www.amazon.com/dp/3540714227/?tag=pfamazon01-20

======================

If you LIKE the "quantum fluctuation" idea, OK that is your business. but if you don't, then have a look at the Spires listing that I linked to. You won't find any quantum fluctuation stuff in the top-cited 10 or 20 articles, I expect. The most highly cited QC research literature is based on computer modeling usually involving a contraction-bounce-expansion. But look for yourself. The articles are all free for PDF download
 
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  • #16
Sorry to intrude ... clearly out of my depth here. But I will check out the links.
 
  • #17
DaveC426913 said:
Science has nothing to say about what preceded the BB; that's for the Philosophy forum.

Most physicists can't accept that 8D
 
  • #18
marcus said:
I wasnt talking about the creation of the universe due to a quantum fluctuation. I don't find that approach very appealing, do you? A fluctuation in what?

If you LIKE the "quantum fluctuation" idea, OK that is your business.

I agree with you, Marcus -- I was responding to Pixchips who was arguing the Hawking view and your post slipped in before mine posted. I wasn't arguing for a quantum fluctuation, I was arguing for an alternative, that neither time nor the universe needs a beginning. I prefer the position you seem to favor, the bounce.

Of course this begs the question of whether there was only one bounce or many. My preferred view would be many, since intuitively it seems that if there was one previous crunch, it should happen again and again. Unfortunately there is as yet no evidence that it will happen again, but if such evidence comes to light it would seem to be strong confirmation of the bounce theory, though I do understand that the bounce theory doesn't require that.
 
  • #19
I see better now what you were saying, Dill. I think earlier I was reacting to several posters without fully understanding. Thanks for clarifying. Our viewpoints seem to be pretty similar.

Dean has a good point too
DeanBH said:
Most physicists can't accept that 8D
RIGHT and I say more power to them. The more of the basic questions they can wrestle out of the grasp of philosophers and apply empirical method to the better! Go physicists!
What does that smilie 8D look like if you use the PF menu? I might like to use it myself
would any of these fit?


:rolleyes:

:bugeye:
 
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  • #20
Hi again ... I'm new to PF and anything I 'know' comes from an eceltic mix of Borders physics shelf, the Discovery channel, and long career as a design engineer, so I didn't mean to 'argue' ... the QF thing doesn't really make sense to me for a lot of reasons, but I hadn't heard the alternatives and was actually (and apparently unsuccessfully) expressing my confusion. To add to my confusion, I was just perusing another thread about CMB in which a learned colleague said that the fate of the universe was known to the extent that it was open: the expansion would continue forever due to the recently revived Cosmological Constant. This was the subject of a recent article (I think it was Scientific American) which argued that the future would see an era in which the local group would be effectively cut off from the rest of the universe by it's own horizon as the expansion continually accelerated. Can both be right? Can the universe be externally oscillatory and continually expanding? (Just to be clear, I am actually asking a question. Sometimes seemingly contradictory things are resolved by a larger viewpoint.) As I said, I can't put any math to this, so I am probably out of my depth. But it is fascinating and confusing.
 
  • #21
pixchips said:
...To add to my confusion, I was just perusing another thread about CMB in which a learned colleague said that the fate of the universe was known to the extent that it was open: the expansion would continue forever due to the recently revived Cosmological Constant.
Hey I actually believe that myself! I just can't guarantee it or speak authoritatively. But it is what LCDM says and LCDM is an awfully good model.

BTW "open" is a tricky term. It used to mean both "expand forever" and "spatially infinite". So it is best to specify what you mean, I think. As you in fact did.
the two things are no longer equivalent, you can have a spatial finite universe that expands forever

This was the subject of a recent article (I think it was Scientific American) which argued that the future would see an era in which the local group would be effectively cut off from the rest of the universe by it's own horizon as the expansion continually accelerated. Can both be right? Can the universe be externally oscillatory and continually expanding? (Just to be clear, I am actually asking a question. Sometimes seemingly contradictory things are resolved by a larger viewpoint.) As I said, I can't put any math to this, so I am probably out of my depth. But it is fascinating and confusing.

Why don't you give folks the link to that article, or some information about the author. Was it by Larry Krauss? I don't read SciAm regularly but they do occasionally publish excellent articles and I like to hear about them!

Krauss (and his co-author) would be giving you the straight consensus LCDM story. It is not OSCILLATORY. It is continually expanding.
One Krauss article is http://arxiv.org/abs/0704.0221 but he may also have something in SciAm.

As far as I know there is no evidence that the universe is OSCILLATORY, and no evidence that it will ever stop expanding.

What you do get from a lot of published quantum gravity research is a BOUNCE, but a person shouldn't let their imagination run away with them and suppose that merely because there was once a bounce that it has to repeat.

just because there was once a crunch and a bounce doesn't mean there ever will be again (no matter how spiritually or aesthetically appealing the idea of cycles or recurrence might be)

the issue is one of these huge gaps in knowledge that we just have to put up with. quantum cosmology makes a one-time bounce plausible and provides model for it, but we don't KNOW. it isn't proven and either way it doesn't say anything about recurrent cycles.
just have to live with the frustration.

Yes! Just as you say. It is indeed fascinating and confusing. Welcome. :biggrin:
 
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  • #22
Hi Again Marcus ... Your comments on 'open' are well taken. And thank you for the clarification on 'bounce'. That is the confusing point ... the universe may have bounced, but it doesn't appear that it will do it again. And ... you are in luck, the magazine has not yet been forced into the recycling bin, it is: Scientific American, March 2008, "The End of Cosmology" by Lawrence M. Krauss and Robert J. Scherrer. It is not as depressing as the title implies, we are a long way off from the epic in question.

"you can have a spatial finite universe that expands forever"

I'm trying to wrap my brain around this: you don't mean just a horizon, you mean that the extent of the universe is finite, but continues to expand. Right now, in our universe, we can look out and see out (almost) to the distance where space is receding at c. That's a horizon, correct? We can't see past this. Are there galaxies beyond this point? Is there a limit to our universe whether we can see it or not?
 
  • #23
marcus said:
I see better now what you were saying, Dill. I think earlier I was reacting to several posters without fully understanding. Thanks for clarifying. Our viewpoints seem to be pretty similar.

Dean has a good point too
RIGHT and I say more power to them. The more of the basic questions they can wrestle out of the grasp of philosophers and apply empirical method to the better! Go physicists!
What does that smilie 8D look like if you use the PF menu? I might like to use it myself
would any of these fit?


:rolleyes:

:bugeye:

it's more of a dancing peanut butter jelly banana type smile.
 
  • #24
DaveC426913 said:
Science has nothing to say about what preceded the BB; that's for the Philosophy forum.

Which isn't true because modern cosmology has very much to say about what probably was before the BB.
 
  • #25
robheus said:
Which isn't true because modern cosmology has very much to say about what probably was before the BB.
Perhaps my information is out-of-date.
 
  • #26
DaveC426913 said:
Perhaps my information is out-of-date.

No it is due to the confusion about what the BB really is and is not. If you happen to think (as is often popularized in media) that the BB means : the (absolute) begin of space,time and matter, yes, than in that case there is "nothing" before the BB.
However, apart from the fact that such is an ill metaphysical position (supposedly "everything" came from "nothing"), this is not what the BB theory really says. The BB just says that the universe was in the far past denser, smaller and hotter. And this is (mainly) based on predictions or solutions to the equations of GR, but which introduce the difficulty that they also produce the so-called "singularity". This ought to mean also that GR predicts it's own break-down (i.e. it can not make predictions of what happens there) near that "singularity". So that "singularity" is just a theoretical point, not the actual point in history in which the universe "began". What cosmologists need is a theory (i.e. a theory of quantum gravity) that can both deal with GR and QM, since both fundamental theories are of importance there and they are to-say not on "speaking terms" with each other.
The whole issue of weather or not time can be said to have a begin (without time, how can anything be said to begin or change?) is however something that is more properly attributed to philosophy.
I would think, most cosmologist would see time as eternal, yet this is appearantly not always the case, and not all models are ruled out by definition that have time begin somewhere.
This is a very "old" philosophical problem (can motion/change arise out of a state of motion/changelessness?)
For cosmology, the only thing of importance if is if such a model makes the right predictions, that can be experimentally tested for (observed).
What the initial BB theory could not explain is why the universe is so flat and why the universe is so homogeneous. Inflation theory could explain that.
Other candidate theories are ekpyrotic universe model, developed in string cosmology.
 

1. What is the Big Bang theory?

The Big Bang theory is the most widely accepted scientific explanation for the origin of the universe. It states that the universe began as a hot, dense, and infinitely small point, known as a singularity, and has been expanding and cooling down ever since.

2. How was the Big Bang discovered?

The Big Bang theory was developed based on observations and experiments made by scientists, such as Edwin Hubble's discovery of the expanding universe and the detection of cosmic microwave background radiation by Arno Penzias and Robert Wilson. These observations provided evidence for the initial conditions of the universe and its expansion, leading to the development of the Big Bang theory.

3. What evidence supports the Big Bang theory?

There are several pieces of evidence that support the Big Bang theory, including the cosmic microwave background radiation, the abundance of light elements, and the expansion of the universe. Additionally, the Big Bang theory can also explain the observed redshift of galaxies and the large-scale structure of the universe.

4. What happened during the Big Bang?

The Big Bang theory describes the expansion and cooling of the universe from a singularity. As the universe expanded, it became less dense and cooler, allowing for the formation of atoms, galaxies, and stars. It is believed that the four fundamental forces of nature (gravity, electromagnetism, strong and weak nuclear forces) were unified in the early universe and gradually separated as the universe cooled.

5. What does the future hold for the universe according to the Big Bang theory?

According to the Big Bang theory, the universe will continue to expand and cool down, eventually leading to the end of stars and galaxies as we know them. The fate of the universe depends on its density and the strength of gravity, with possible outcomes including a "big freeze" or a "big rip". However, the exact fate of the universe is still a topic of scientific debate and research.

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