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  #1  
Old 02-28-2008, 05:20 PM
World's Biggest Caner World's Biggest Caner is offline
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Where does all the matter in the universe come from?

Where does all the matter in the universe come from?

I'm no but astrophysicist but I understand a little about the Big Bang Theory and also that there's lots of stuff we don't know or probably ever will know about it.

But the universe is awfully big and must have an awful lot of matter in the form of asteroids, stars, asteroids and suchlike. Did all matter in the universe originally exist at the centre of the Big Bang or is new matter being constantly created? If so, how?

Apologies if this is an elementary astrophysical question but I couldn't find the answer web-browsing...
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  #2  
Old 02-28-2008, 08:09 PM
DrFidelius DrFidelius is online now
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All of the matter in the Universe is made from some of the energy of the Universe, clotted up into lumps. All of the energy has been there since forever.
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Old 02-28-2008, 09:05 PM
World's Biggest Caner World's Biggest Caner is offline
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Okay, I know that energy takes many forms and that it can be converted to other forms but that it can't be created or destroyed. How does or did the energy turn into matter?

Was all the matter in the Universe created at the moment of the Big Bang?
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  #4  
Old 02-28-2008, 09:31 PM
Exapno Mapcase Exapno Mapcase is offline
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Quote:
Originally Posted by World's Biggest Caner
Was all the matter in the Universe created at the moment of the Big Bang?
Yes, it was. Dense doesn't begin to describe it.

Matter formed as the temperature of the universe cooled, allowing particles to form and stay in existence.

Steven Weinberg wrote the classic book on the subject many years ago, The First Three Minutes (which has been revised and updated since).

This physics page provides a very, very condensed version.
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Old 02-28-2008, 09:42 PM
gonzomax gonzomax is offline
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Matter is frozen energy.
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Old 02-29-2008, 03:56 AM
nivlac nivlac is offline
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My favorite answer is from Alan Guth: "It is said that there's no such thing as a free lunch. But the universe is the ultimate free lunch."

And if that's not good enough for you, just say "quantum transition" .
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Old 02-29-2008, 09:44 AM
Philster Philster is offline
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Quote:
Originally Posted by DrFidelius
All of the matter in the Universe is made from some of the energy of the Universe, clotted up into lumps. All of the energy has been there since forever.
But 'forever' is a finite am't of 'time'.
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  #8  
Old 02-29-2008, 10:44 AM
BarnOwl BarnOwl is offline
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Doper Cosmologists...

It doesn't blow your mind that all the stuff out there (pick your favorite
Hubble photos of the jillions of galaxies) all came from a speck that was
smaller than an atom?

Are the calculations for the Singularity such, that the ongoing discovery
of new galaxies never makes that speck one iota bigger or denser?

Don't make fun.
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Old 02-29-2008, 11:21 AM
Small Clanger Small Clanger is offline
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Originally Posted by World's Biggest Caner
Where does all the matter in the universe come from?
Ahh, today with the easy questions? I think this one boils down to Why is there something rather than nothing? and I don't think anyone has really cracked that one, unless you want to simply blame the Flying Spaghetti Monster for the whole mess.
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  #10  
Old 02-29-2008, 11:23 AM
World's Biggest Caner World's Biggest Caner is offline
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So matter is cooled or frozen energy. Me throwing a ball is a form of energy but I find it hard to imagine that energy turning into a rock of iron or lead...or even a grain of sand! What form of energy was being converted into matter? What forms of energy were there at the moment of the Big Bang?

Is that fact that "all the stuff out there...all came from a speck that was smaller than an atom"? How can something smaller than an atom create all the atoms in the whole Universe? It sounds impossible to fit that much energy in such a miniscule space. "Dense doesn't begin to describe it" sounds like a slight understatement...!
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  #11  
Old 02-29-2008, 11:31 AM
Exapno Mapcase Exapno Mapcase is offline
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This is not a subject that can be answered in a paragraph. You need background just to get the concepts, and then explanation of each concept and how it fits together into the whole.

I'm very serious when I say, read a book. The cosmology section of a library or bookstore will have dozens of books attempting to make the subject comprehensible to those who haven't studied physics. The issue for us is that every single question you ask requires a chapter or two just to begin answering. Just the basics of a question like what is energy will fill up the first half of a book. And you need to read that entire first half to get to the weird stuff in the second half.

A number of real working scientists have written top-notch, understandable, readable books in recent years. Even if they seem overwhelming, they start from easy beginnings and lead the reader gradually deeper and deeper. It's truly worth the effort and you'll get a thousand times more out of it than you will from here. We just don't have the time or the space. (Yes, pun intended.)
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Old 02-29-2008, 11:33 AM
BarnOwl BarnOwl is offline
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Quote:
Originally Posted by World's Biggest Caner
So matter is cooled or frozen energy. Me throwing a ball is a form of energy but I find it hard to imagine that energy turning into a rock of iron or lead...or even a grain of sand! What form of energy was being converted into matter? What forms of energy were there at the moment of the Big Bang?

Is that fact that "all the stuff out there...all came from a speck that was smaller than an atom"? How can something smaller than an atom create all the atoms in the whole Universe? It sounds impossible to fit that much energy in such a miniscule space. "Dense doesn't begin to describe it" sounds like a slight understatement...!
I think that's Exapno Mapcase's point: The density is so great, it is probably beyond anyone's ability to comprehend, and thus beyond anyone's ability to articulate meaningfully. Except, perhaps, in a mathematical formula where you just scratch out the sign for infinity. How meaningful would that be for you, for me, for most of us in the world?
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  #13  
Old 02-29-2008, 11:37 AM
Giles Giles is online now
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Quote:
Originally Posted by Exapno Mapcase
We just don't have the time or the space. (Yes, pun intended.)
You should have said, "We don't have the time, or the space, or the energy."
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  #14  
Old 02-29-2008, 11:38 AM
Triskadecamus Triskadecamus is offline
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Perhaps the singularity contained within it all the possible values for all the characteristics, such as temperature, granularity population, and the various values for the various "constants" we observe. The "universe" is the expression of that aspect for which duration of the singularity could be greater than zero. Other aspects might exist, however their duration is not contiguous with our own.

Tris
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Old 02-29-2008, 11:49 AM
WhyNot WhyNot is online now
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Quote:
Originally Posted by World's Biggest Caner
Okay, I know that energy takes many forms and that it can be converted to other forms but that it can't be created or destroyed. How does or did the energy turn into matter?
Answer from a Chemistry 101 student, so take this with a huge grain of NaCl:

It doesn't "turn into" matter. Everything is energy, just slower or faster, more energy or less energy. When something has very little energy, we call it "matter" - when it holds very little energy even compared to other matter, we call it a "solid" and when it contains quite a bit of energy when compared to other matter, we call it a "gas". (Somewhere in between is a "liquid".)

A hydrogen atom, at the scale of something, well, scalable, is about like a baseball stadium - the pitcher's mound is the nucleus, and way out in the back bleachers is a gnat flying around. That's the electron. Almost the entire "atom" is empty space. The "particles" (the proton and neutron in the nucleus and the electron) are nothing - they're energy. They're a tendency for energy to act in a predictable way. There's a bit of energy <here> that tends to repel a bit of energy <here> and so we call one the proton and one the electron, but they're not, strictly speaking, bits of anything at all. They're energy. And somehow, all that energy "adds up" somehow, to a hydrogen atom. Which, in turns, hangs out with other atoms, interacts in funny ways, and when enough of them hang out with enough oxygen atoms, I get to drink the water. Which, of course, is nothing but energy. As am I.

Yes, sooner or later, chemists and physicists sound a whole lot like metaphysical gurus and stoners.
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  #16  
Old 02-29-2008, 11:51 AM
World's Biggest Caner World's Biggest Caner is offline
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Is it physically possible for something to be that dense in the Universe now or were the rules of the Universe not set before the moment of the Big Bang? (I realise that may be an impossible question to answer...).

P.S. If you can suggest a "birds and the bees" style book on astrophysics and the formation of the Universe please tell. Something lighter on the equations and heavier on heavier on the analogies and story-telling. "Once upon a time there was a little atom all alone in the Universe and he decided he wanted some friends to play with..."
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Old 02-29-2008, 11:52 AM
gonzomax gonzomax is offline
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The explosion that started it off released an enormous amount of energy .It was extremely hot. As it cooled it coalesced into the building block chemicals that constitute the universe, Slowly as it cooled ,it created more and more building components. Solid objects came billions of years later.
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Old 02-29-2008, 11:58 AM
World's Biggest Caner World's Biggest Caner is offline
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I like the baseball analogy. Continuing along the same lines, if the whole Universe Big Bang-ed from something smaller than an atom what might that uber-atom have looked like if it were a baseball stadium...?
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Old 02-29-2008, 12:02 PM
World's Biggest Caner World's Biggest Caner is offline
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Yes, if you could try and explain the formation of the Universe purely in terms of baseball stadiums, pitchers mounds and gnats it would be much appreciated...
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Old 02-29-2008, 12:08 PM
Triskadecamus Triskadecamus is offline
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Quote:
Originally Posted by gonzomax
Solid objects came billions of years later.
Perhaps not all that long, though. This (and other recent observations) has stirred the pot on the recipe for a new universe, in the last decade or so.

Tris
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Old 02-29-2008, 12:38 PM
Exapno Mapcase Exapno Mapcase is offline
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Quote:
Originally Posted by World's Biggest Caner
Is it physically possible for something to be that dense in the Universe now or were the rules of the Universe not set before the moment of the Big Bang? (I realise that may be an impossible question to answer...).
You can't think of energy density in the same way that you think of density of matter. There was no mass at all in the inflationary universe. You can't compare that to the density of matter today.

In the same way you can't ask what forms of energy there were. It's more than just not containing matter: none of the basic forces of the universe - strong force, weak force, electromagnetism, and gravity, and any other "fifth" forces that we may discover - existed yet either. Without those we don't have meaningful words to describe "forms" of energy.

The baseball stadium analogy doesn't work either. That's just a variation of the old "solar system" analogy and that's been discredited. The electron isn't like a gnat in an outfield. It is a probability distribution. What is that? It's a quantum thing. You wouldn't understand.
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  #22  
Old 02-29-2008, 01:04 PM
Spatial Rift 47 Spatial Rift 47 is offline
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Alright, I'll take a crack at this. In order to answer this question, to really truly understand where energy and matter come from, you have to understand spacetime, the fabric of the Universe, on a quantum level. (Note: no one has done this yet.)

You see, physicists have figured out that because of the inherent indeterminacy of the Universe on quantum scales (the miniscule volumes in which the interaction between individual particles becomes significant), the so-called "vacuum" actually allows for particles to appear and disappear again. This means that if you have some initial state (an initial arrangement of energy in the form of, let's say, photons of light) as those photons zip around, the vacuum allows some of that energy to be spontaneously converted into pairs of particles and antiparticles.

Usually a particle and its antiparticle will immediately combine and annihilate into energy again. This gives rise to another great question in cosmology: Why do we see so much matter and so little antimatter? Possible answers to this include: "we simply happen to be in a relatively small, localized region of matter and there's lots more antimatter way the hell out in space", and "there's a teeny tiny asymmetry to the laws of physics and slightly more matter was created than antimatter, and we're what's left over after the rest annihilated".

You'll notice I left one question completely unanswered: Why was there some initial energy? This is why, as Small Clanger noted, your question is the same as asking "Why is there something rather than nothing?"

Let me know if you figure that one out. I know some guys in Stockholm that would be very interested in your answer.
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  #23  
Old 02-29-2008, 04:39 PM
Pasta Pasta is offline
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Although the situation is not exactly the Big Bang, here's a visual example of matter being created from energy: electron-positron pair production.

A caption: High energy photons coming in from the left convert into electron/positron(=anti-electron) pairs. The electrons and positrons leave visible tracks in the detector (here, a so-called bubble chamble), and a magnetic field bends their trajectories by an amount inversely proportional to their momentum. There are two separate photon conversions in the image, one on the right and one on the left. The extra track in the left one is a scattered atomic electron.

Poof. Matter.

(I don't want to mislead. The Big Bang is not simply a scaled-up version of this. But, particle production like this is a key component of the answer to the original question in the OP.)
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Old 02-29-2008, 04:42 PM
Corner Case Corner Case is offline
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If you want analogies, consider this along with the baseball stadium.

It is theorized that neutrons, protons, electrons, and other wave/particles are made up of smaller bits of energy called Strings. Imagine these as little circles made of fuzzy energy that wiggle up and down like ~~~~~~~ wrapped around on itself and the highs and lows are dipping up and down like a merry-go-round. Then, don't mention this analogy to anyone who has studied physics or they won't talk to you anymore.

Now, for scale, first imagine the solar system. There are many models here: http://www.vendian.org/mncharity/dir3/solarsystem/. If you want to calculate your own model, you can use this http://www.exploratorium.edu/ronh/so...ll_bodies.html site. Then if you want to see a scale model, check out this page http://www.phrenopolis.com/perspecti...tem/index.html .

When you get the scale of the solar system in mind, let me know, because I haven't done it. Now consider that a String is to the size of an atom what an atom is to the size of the Solar System. When you grasp this an emerge from your coma, you might be able to see how all the matter, which is energy, which might be formed of Strings could be squished into a really... small size.
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Old 02-29-2008, 06:12 PM
God of Biscuits God of Biscuits is offline
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Quote:
Originally Posted by World's Biggest Caner
Is it physically possible for something to be that dense in the Universe now or were the rules of the Universe not set before the moment of the Big Bang? (I realise that may be an impossible question to answer...).
What you're describing sounds very much like the surprise at the middle of a black hole. Does such a thing really exist? The world may never know.

Quote:
Originally Posted by World's Biggest Caner
P.S. If you can suggest a "birds and the bees" style book on astrophysics and the formation of the Universe please tell. Something lighter on the equations and heavier on heavier on the analogies and story-telling. "Once upon a time there was a little atom all alone in the Universe and he decided he wanted some friends to play with..."
I would definitely recommend A Brief History of Time by Stephen Hawking. Easily available at any book store and walks you through all of cosmology in simple(ish) terms.

Hope this helps!
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Old 02-29-2008, 09:33 PM
Exapno Mapcase Exapno Mapcase is offline
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People always seem to get the understanding of a black hole wrong.

A black hole occurs when enough mass is gathered together in a volume to prevent light from escaping. The size of a black hole depends on the mass of a black hole. A black hole can be any size from microscopic to the diameter of the universe. In fact, if the input the mass of the universe into the equations, you would get a black hole with about the diameter of the universe. The density inside the escape horizon would not be all that great, obviously. It would be almost all empty space.

So the density inside a black hole is not a constant and is not necessarily enormous.

There is a black hole that is assumed to be at the center of our Milky Way galaxy. Estimates are that it contains about 4 million times the mass of the sun, but is at least a billion miles across. That's a lot of mass, but the density is obviously a tiny, tiny, tiny fraction of what the early universe was.
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  #27  
Old 02-29-2008, 11:46 PM
Ring Ring is offline
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The total energy of the universe is for all practical purposes zero.

The positive energy of all the particles is almost exactly balanced by the negative gravitational potential energy.

Itís pretty easy to visualized 0+ energy contained in a very small volume. Donít you think?
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  #28  
Old 02-29-2008, 11:51 PM
Ring Ring is offline
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Originally Posted by Exapno Mapcase
There was no mass at all in the inflationary universe. You can't compare that to the density of matter today.
Sorry to disagree EM, you pretty much always know your stuff, but in this case you're not correct. There was exactly the same amount of mass in the very early universe as there is today.
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Old 03-01-2008, 01:33 AM
Triskadecamus Triskadecamus is offline
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Originally Posted by Ring
Sorry to disagree EM, you pretty much always know your stuff, but in this case you're not correct. There was exactly the same amount of mass in the very early universe as there is today.
. . . for certain definitions of mass, and some values of very early.

Tris
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Old 03-01-2008, 10:15 AM
Ring Ring is offline
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Originally Posted by Triskadecamus
. . . for certain definitions of mass, and some values of very early.

Tris
Pardon me?? Very early what?

There's only one definition of mass that all physicists agree on.

m2 = E2 - p2 ( c = 1 )

Or verbally

Energy that cannot be transformed away.

I await your further enlightenment.
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Old 03-01-2008, 10:38 AM
Triskadecamus Triskadecamus is offline
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Originally Posted by Ring
There's only one definition of mass that all physicists agree on.
Well, it's nice to hear they actually agree on something.

However, various descriptions of the instant after creation describe the universe as entirely composed of photons. And various description of photons insist that they have no mass. So, for some values of very early, it seemed to me that the universe had no mass, for some definitions of mass.

Tris
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Old 03-01-2008, 11:19 AM
Ring Ring is offline
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Originally Posted by Triskadecamus
Well, it's nice to hear they actually agree on something.

However, various descriptions of the instant after creation describe the universe as entirely composed of photons. And various description of photons insist that they have no mass. So, for some values of very early, it seemed to me that the universe had no mass, for some definitions of mass.

Tris
A system of photons that has (actually "have" sounds better here) a zero momentum frame has mass; which must be the case in the very early universe.

Also the magnitude of the energy-momentum four- vector is not zero, and mass equals this magnitude. Since momentum is conserved these values for mass cannot change as the universe ages.

An interesting fact: If the universe is now infinite it must have been infinite at the big bang.
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Old 03-01-2008, 11:29 AM
Ring Ring is offline
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Quote:
Originally Posted by Ring
A system of photons that has (actually "have" sounds better here) a zero momentum frame has mass; which must be the case in the very early universe.

Also the magnitude of the energy-momentum four- vector is not zero, and mass equals this magnitude. Since momentum is conserved these values for mass cannot change as the universe ages.

An interesting fact: If the universe is now infinite it must have been infinite at the big bang.
Well I screwed that up. It should read:

A system of photons that has a zero momentum frame has mass, which must be the case in the very early universe. Since momentum is conserved these values for mass cannot change as the universe ages.

Also the magnitude of the energy-momentum four-vector is not zero, and mass equals this magnitude.

An interesting fact: If the universe is now infinite it must have been infinite at the big bang.
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  #34  
Old 03-01-2008, 11:36 AM
Exapno Mapcase Exapno Mapcase is offline
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Quote:
Originally Posted by Ring
Sorry to disagree EM, you pretty much always know your stuff, but in this case you're not correct. There was exactly the same amount of mass in the very early universe as there is today.
In trying to oversimplify the complicated, I always hit a point where the experts step in. Yes, obviously mass and energy are equivalent. But I was trying to make the point that physical particles of massed matter, as in the stuff that composes the universe today and in also the stuff that black holes are made of, were not present in the early universe. I used mass rather than matter because otherwise I would get into the nitpick that photons or other basic units could be called matter. I lose either way. Bear in mind that I'm trying to explain this stuff in the simplest possible language. Feel free to correct me when I obscure a technicality this way, but also remember that the audience we're writing for understands none of the basic concepts.
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Old 03-01-2008, 12:33 PM
Ring Ring is offline
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Originally Posted by Exapno Mapcase
In trying to oversimplify the complicated, I always hit a point where the experts step in. Yes, obviously mass and energy are equivalent. But I was trying to make the point that physical particles of massed matter, as in the stuff that composes the universe today and in also the stuff that black holes are made of, were not present in the early universe. I used mass rather than matter because otherwise I would get into the nitpick that photons or other basic units could be called matter. I lose either way. Bear in mind that I'm trying to explain this stuff in the simplest possible language. Feel free to correct me when I obscure a technicality this way, but also remember that the audience we're writing for understands none of the basic concepts.
Any simplifying statement in physics can be nitpicked, and I would normally leave these alone. But your statement that "there is no mass at all........." was more than I could bear. In any case I find you to be one of the more enlightened posters on the SDMB and I always enjoy reading your stuff.
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  #36  
Old 03-01-2008, 01:06 PM
Ring Ring is offline
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And BTW in order to avoid nitpickers like myself I would have made your point by saying something like:

In the very early universe the only particles that existed were photons which individually have no mass.
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Old 03-01-2008, 03:57 PM
mudd mudd is offline
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Originally Posted by Ring
An interesting fact: If the universe is now infinite it must have been infinite at the big bang.
This begs the question; where did the big bang occur? If I was to go outside and look up, in which direction should I point, to indicate where it all started?
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Old 03-01-2008, 04:35 PM
Liberal Liberal is offline
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Originally Posted by Small Clanger
Ahh, today with the easy questions? I think this one boils down to Why is there something rather than nothing? and I don't think anyone has really cracked that one, unless you want to simply blame the Flying Spaghetti Monster for the whole mess.
Exactly. The OP is a GD question.
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Old 03-01-2008, 09:28 PM
Exapno Mapcase Exapno Mapcase is offline
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Originally Posted by mudd
This begs the question; where did the big bang occur? If I was to go outside and look up, in which direction should I point, to indicate where it all started?
The big bang occurred everywhere. There is no privileged center to the universe. It is identical on the largest scales in all directions and from all perspectives.

That means there is no answer to your question. The big bang was not a place, not a center from which things emerged. It affected everything all at once. This is hard to understand, but any good book on the big bang will try to explain it in more words than we can post here.
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Old 03-01-2008, 11:40 PM
Triskadecamus Triskadecamus is offline
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I am still counting my photons, wondering how many times 0 + 0 is not going to equal zero. Do you just squeeze the pencil real hard, or something?

Not to mention wondering how all these concepts which are defined in the universe now in terms of seconds, and meters are going to turn out when both of those values are 0 too. If E=mc2, and c is zero, then well so is everything else. Anything defined with either length, or time in the value is . . . well, undefined, or zero. Doesn't momentum have a velocity in it somewhere? In fact, I am informed that the momentum of a massless particle is Planck's constant divided by wavelength, and in this example the wavelength must be zero, so the momentum has to be undefined, not zero.

One entire Planck interval later, I will believe pretty much however much matter or energy you want, but the actual instant of the singularity strikes me as . . . well, zero. I could live with undefined, however, as it seems appropriate. However, it seems to me that zero is a fairly small value of early. And the sum of an infinite number of zeros looks like a pretty small mass.

I am not a physicist. But, I don't think it's as sewn up as it is being presented.

Also, whatever it is that causes the Heisenberg Uncertainty ain't operating yet, either, because everything is moving at the same velocity, namely zero, and has precisely the same location, namely right here. It seems to be an inherently unstable situation, and I expect it will all fall apart shortly. But that's later, this is now.

Tris
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  #41  
Old 03-01-2008, 11:55 PM
Exapno Mapcase Exapno Mapcase is offline
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This is why current theories of physics are considered to be incomplete and more complete theories - string theories or loop quantum gravity or whatever the flavor of the week is - are going to take over one day.

In the meantime, physics says nothing about what happened at time zero. It picks up later when the equations no longer go to zero or infinity. However, that is mostly irrelevant to this discussion. The Big Bang, or better, inflation, took place after the zero point and can be described by current physics. This is also where Small Clanger and Lib get it wrong. Everything in this thread is related to descriptions of physical processes of energy and matter and need no philosophy to explain why we're dealing with something rather than nothing. We're dealing with something by definition. Their concerns are for a different question not stated by the OP, who specifically referenced the Big Bang, or the responders.
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Old 03-02-2008, 12:54 AM
Triskadecamus Triskadecamus is offline
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Originally Posted by Exapno Mapcase
Their concerns are for a different question not stated by the OP, who specifically referenced the Big Bang, or the responders.
Yeah, I suppose the actual instant of creation is not actually part of the Big Bang. You do understand that that is not readily apparent to a non mathematical frame of reference?

Tris
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  #43  
Old 03-02-2008, 02:18 AM
Saltire Saltire is offline
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Tris, I just have to say that your post #40 is beautifully written. It really gets to the way that physics just totally fails when you run it backwards far enough, while accepting that it works very well at all points after that (to the best of our current understanding).
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Old 03-02-2008, 02:50 AM
Triskadecamus Triskadecamus is offline
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Quote:
Originally Posted by Saltire
Tris, I just have to say that your post #40 is beautifully written.
Thanks. Evidently my real skill in science is how well I don't understand it.

Who'd uh thunk it?

Tris
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  #45  
Old 03-02-2008, 02:08 PM
World's Biggest Caner World's Biggest Caner is offline
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Hi, fascinating to hear you guys wrestle with this stuff (I assume you're all guys as you seem to be astrophysicists... ).

I thought this subject might be beyond the comprehension of the human mind, but it seems it's even bigger than that! I mean if you want to know about the nature of God you're better off reading a book on astrophysics than the Bible or other holy tome (no offence intended to the faithful). So anyway, I'll get a book...

Are you guys in general agreement that the whole Universe was originally an unfathomably dense "smidgen" of energy smaller than an atom? I mean, that's like totally OMG!
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  #46  
Old 03-02-2008, 10:40 PM
Triskadecamus Triskadecamus is offline
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Originally Posted by World's Biggest Caner
Hi, fascinating to hear you guys wrestle with this stuff (I assume you're all guys as you seem to be astrophysicists... ).
Well, I change diapers for a living.
Quote:
I thought this subject might be beyond the comprehension of the human mind, but it seems it's even bigger than that! I mean if you want to know about the nature of God you're better off reading a book on astrophysics than the Bible or other holy tome (no offence intended to the faithful). So anyway, I'll get a book...
Try this one: Big Bang by Simon Singh. It's a history of cosmology, not a physics textbook. It gives a nice overview of how some very smart people came to think some very different things about the absolute unassailable truth of cosmological physics.
Quote:
Are you guys in general agreement that the whole Universe was originally an unfathomably dense "smidgen" of energy smaller than an atom? I mean, that's like totally OMG!
We seem to be in relative concordance about smaller than an atom. It's smaller than a Planck unit we start having troubles with.

Tris
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  #47  
Old 03-02-2008, 10:51 PM
phil417 phil417 is offline
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Might one ask a question? Where was it before it began? Philosophers say there's always a beginning. So what was before the beginning?

As a religious, I've an answer. My answer also is to this question. God.
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  #48  
Old 03-02-2008, 10:58 PM
Triskadecamus Triskadecamus is offline
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Originally Posted by phil417
Might one ask a question? Where was it before it began? Philosophers say there's always a beginning. So what was before the beginning?

As a religious, I've an answer. My answer also is to this question. God.
The physics question has a different answer than the religious question.

What is north of the north pole?

Religious answers belong in a different thread. Never try to prove the existence of God. It's disrespectful.

Tris
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  #49  
Old 03-02-2008, 11:44 PM
Exapno Mapcase Exapno Mapcase is offline
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Quote:
Originally Posted by phil417
Might one ask a question? Where was it before it began? Philosophers say there's always a beginning. So what was before the beginning?

As a religious, I've an answer. My answer also is to this question. God.
Talk to enough philosophers and you will find every possible answer to every question. Therefore, it's not true that all philosophers say there's always a beginning.

There are also numerous physical ways to answer the question of what came before the big bang. We don't know which, if any, are right, but none of them require a god.

If that's your answer, fine. You don't seem to want to debate it or look for a physical answer, though. Even so, there are always physical answers and many of the books that talk about the big bang will also give current hypotheses about what happened before the "beginning."
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  #50  
Old 03-03-2008, 03:30 AM
The Hamster King The Hamster King is offline
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Quote:
Originally Posted by phil417
My answer also is to this question. God.
Which one? There are so many ... .
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