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jamesabrown
2008-Oct-30, 04:47 PM
Help me with a question regarding the universe, please, although I'm not sure if I can ask this properly without straying into forbidden topics on this board. My question stems from a religious debate, and I'll try to keep this as neutral as possible.

One side of the debate argued that Something Created Everything out of Nothing. The other side argued that Everything came from Nothing.

My problem comes from the second argument, namely, Nothing Became Something. That's not how I see it, so I'm here to be corrected if need be.

As far back as we can detect, there has always been Something in the Universe. Eventually, we reach a point where the collapse of the laws of physics make everything opaque, so that we can't "see" anything. To view further back we have to extrapolate what we know about atoms and energy, role-playing as it were what they would do under certain conditions, to the point where we have a good idea of what happened within a tiny fraction of a second after the Big Bang. But never do we reach a point where there is nothing at all. What happened 'before' the Big Bang is impossible for anyone to know on two levels. First, no information survives from the prior existence of the singularity, and Second, there can't be a 'before' before Time began.

In other words, the Big Bang was not a Creation event but merely an Expansion event--an expansion of pre-existing matter and energy, albeit in a non-understandable form. I know that many people refer to the Big Bang as the Fires of Creation or whatever, but to my view, I see it as "creating" cookies by cooking dough in the oven, not spontaneously generating cookie molecules out of thin air.

So if someone asked me if I think that Everything came from Nothing, I would have to say, No I don't. I fall back on my default position that, as my hero Carl Sagan said, The Cosmos is all that is, and all that ever was, and all that ever will be.

Or am I just confused?

Jeff Root
2008-Oct-30, 05:10 PM
I don't know whether you are confused, and if you are, I don't know if you
are any more confused than anyone else. But I have some thoughts.

So far, the "creation event" which started the Universe has not been
described. There are many ideas about it, but so far nothing which seems
to be an adequate description. So we just don't know how the Universe
got started. It may have sprung from nothing, or it may have come from
something. That something might have been another universe, or it might
have been empty space, or it might have been something "else" entirely.

It is possible that time began with the creation event. In that case, there
was no "before" the creation of the Universe.

The most promising idea that I know of regarding the creation is that
the total gravitational potential energy of the Universe may be exactly
equal and opposite to the "positive" energy of all matter in the Universe.
In that case, the creation event did not involve a creation of energy, but
the separation of positive energy of matter from negative gravitational
potential energy. The sum of the two always equals zero.

-- Jeff, in Minneapolis

Argos
2008-Oct-30, 05:11 PM
As a matter of fact, there´s no useful way to discuss such matters from a scientific stand point. We must limit ourselves to trying to explain what is observed. Anything beyond that does fall in forbidden categories here.

Cougar
2008-Oct-30, 06:29 PM
As physics Nobelist Leon Lederman put it....




"The laws of nature must have existed before even time began in order for the beginning to happen. We say this, we believe it, but can we prove it? No."

Before 8 or 10 years ago, everything that I read about the big bang described the beginning of the expansion as also the beginning of time, therefore squelching any question of "before," since without time, there is no "before."

More lately, however, the descriptions seem to have shifted a bit. As Jeff noted, we simply don't know if there was a "before" or not. People now refer to the beginning of our expansion, and the beginning of our time, leaving open the possibility that there might have been something "before," which is correct, since we don't know.

Sagan summed things up thusly....




Ten or twenty billion years ago, something happened -- the Big Bang, the event that began our universe. Why it happened is the greatest mystery we know. That it happened is reasonably clear. [emphasis added]

astromark
2008-Oct-30, 06:37 PM
As a matter of fact, there´s no useful way to discuss such matters from a scientific stand point. We must limit ourselves to trying to explain what is observed. Anything beyond that does fall in forbidden categories here.

That statement is false.
Jamesabrown; No, I do not see any confusion in your thinking. Quoting Carl Sagan is not a confused mind. We can and should be free to discuss this argument without disturbing those who see things differently. Jeff has shown the way we think and I see no conflict with any of it. It is a question and answers forum. We can not expect 100% agreement. Some discussion is in fact healthy as it further cements any polarity as just that. I applaud your view and support your right to have one. Any support of the scientific principals is healthy.

Argos
2008-Oct-30, 06:56 PM
That statement is false.

Not from a materialistic, empirical angle. I wish you luck with the enterprise of knowing the "before" [tell me about the result of your quest, if you eventually arrive at any conclusion - I´m eager to know it too].

sohh_fly
2008-Oct-30, 07:16 PM
i have a question, which is.
how can we say for certain that the creation of the universe came from a big bang?
i know that the CMB points to that direction, but maybe the cmb is from something else? could this statement be correct?.
what would of caused the bang,this theory seems to reach pretty far and also that much matter in a infintely small space is hard to fathom.
and why did it bang 13-14 billion years ago,getting something from nothing is a very nifty feat.Is this cmb all over the universe or in a concentrated area of the sky?

Argos
2008-Oct-30, 07:29 PM
Is this cmb all over the universe or in a concentrated area of the sky?

All over the Universe. It is the Cosmic Microwave background. :)

Jeff Root
2008-Oct-31, 12:46 AM
how can we say for certain that the creation of the universe came
from a big bang?
"Big Bang" is pretty descriptive. Everything is flying apart, as if from
an explosion. But we don't know what caused everything to start
flying apart. We can be practically certain that in the time period
which is extrapolated backward to be between ten seconds and ten
minutes after "time zero", the density, temperature, pressure, and
composition of the Universe had certain values that were changing
at certain rates which resulted in the observed primordial abundances
of hydrogen, deuterium, helium, and lithium -- the lightest nuclear
isotopes. But for earlier than that time all we can do is extrapolate,
appying known physics. The problem with extrapolating like that is
that known physics is not enough. Something happened back then
which is not happening now, and we don't know what it was, so we
can be completely certain that at some point, when we extrapolate
far enough back in time, the extrapolation must be wrong. We just
don't know when it starts to go wrong.



i know that the CMB points to that direction, but maybe the cmb is
from something else? could this statement be correct?.
Lots of people have tried and tried and tried to explain the CMBR as
something other than redshifted light from hot hydrogen atoms some
13.7 billion years ago, but nobody has come up with any explanation
that works nearly as well. The CMBR has the most perfect blackbody
radiation curve ever measured. That makes it awfully unlikely that it
is anything other than blackbody radiation.



what would of caused the bang,this theory seems to reach pretty far
and also that much matter in a infintely small space is hard to fathom.
We know that it must have had a high enough density to fuse protons
and neutrons into deterium, helium, and lithium at a temperature of
about 1 billion kelvins. The density and temperature fell continuously,
limiting the quantities of nuclear isotopes produced.

What the density was before the era of nucleosynthesis began is just
unknown -- all we can do is extrapolate backwards, to a point in time
when the density was infinite.

Interestingly, there really is not much matter in the Universe compared
to the amount of space. About three atoms per cubic metre. Contrast
that with the 5,000,000,000,000,000,000,000 atoms in a drop of water.

What that means is that all the matter in the visible Universe could fit
into a very small volume even if it was all at the standard density of
water -- 1 gram per cubic centimetre. All the stars in all the galaxies
we can see, if packed together like enormous beach balls of various
sizes, would fit comfortably within our own Solar System's Oort Cloud.
So the idea of all that matter being squished down into a small volume
isn't quite so outrageous as it might seem.



and why did it bang 13-14 billion years ago, getting something from
nothing is a very nifty feat. Is this cmb all over the universe or in a
concentrated area of the sky?
The cosmic microwave background is seen in all directions. It is very
even across the whole sky, to within a small fraction of a degree,
when proper motions of the Earth are accounted for. Everywhere in
the Universe, observers currently see a microwave background which
originated 13.7 billion years ago from hot hydrogen gas which, at the
time of emission, was 42 million light-years away from the current
location of the observer. The light traveled a distance of 13.7 billion
light-years to reach the observers because of the continual expansion
of the Universe during the time the light was en route.

-- Jeff, in Minneapolis

sohh_fly
2008-Oct-31, 01:45 AM
wow, i never thought that the solar system was big enough to contain all the stars in the universe considering that there is close to 100 billion galaxy's.
thats incredible thx for the clarity jeff.

also why wasn't there nothing else created in that big bang other than the hydrogen,helium,lithium . if supernovas create the metals in the universe ..the big bang had to be the biggest supernova possible?

Cougar
2008-Oct-31, 02:53 AM
also why wasn't there nothing else created in that big bang other than the hydrogen,helium,lithium . if supernovas create the metals in the universe ..the big bang had to be the biggest supernova possible?

Good question, and there's a definite answer. As Jeff's very excellent post mentioned, it's because the very hot universe at that very early time was expanding and cooling very quickly, so there was only a brief window of time for nuclear fusion to occur. Plus, there are no stable nuclei with atomic weights of 5 or 8, which limited the Big Bang to producing hydrogen and helium. As clarified on this detailed page by Ned Wright (http://www.astro.ucla.edu/~wright/BBNS.html) only the longer time scales present in stars allow the triple-alpha process (He+He+He -> C) to proceed and make the elements heavier than helium.

Spaceman Spiff
2008-Oct-31, 03:22 AM
Good question, and there's a definite answer. As Jeff's very excellent post mentioned, it's because the very hot universe at that very early time was expanding and cooling very quickly, so there was only a brief window of time for nuclear fusion to occur. Plus, there are no stable nuclei with atomic weights of 5 or 8, which limited the Big Bang to producing hydrogen and helium. As clarified on this detailed page by Ned Wright (http://www.astro.ucla.edu/%7Ewright/BBNS.html) only the longer time scales present in stars allow the triple-alpha process (He+He+He -> C) to proceed and make the elements heavier than helium.

Not to mention the much higher densities within stellar cores which are fusing helium...

timb
2008-Oct-31, 04:49 AM
Good question, and there's a definite answer. As Jeff's very excellent post mentioned, it's because the very hot universe at that very early time was expanding and cooling very quickly, so there was only a brief window of time for nuclear fusion to occur. Plus, there are no stable nuclei with atomic weights of 5 or 8, which limited the Big Bang to producing hydrogen and helium. As clarified on this detailed page by Ned Wright (http://www.astro.ucla.edu/~wright/BBNS.html) only the longer time scales present in stars allow the triple-alpha process (He+He+He -> C) to proceed and make the elements heavier than helium.

Everything I've read says the standard big bang nucleosynthesis model predicts that 7Li should also have been produced, and in greater quantities than observed.

Cheap Astronomy
2008-Oct-31, 09:15 AM
There's a danger of making too much of words in this sort of discussion. The words something and nothing stand for stuff we are only beginning to understand, so we should be cautious about attributing a level of wisdom to our capacity to work them into sentences.

Given the current state of cosmology where we know what 4% of the universe is (the rest being dark matter and energy - or 'wtf is that?'), no-one should be feeling they know what the word something really means. And from that basis trying to define nothing as the absence of something is equally unsatisfactory.

My 2c worth.

Cougar
2008-Oct-31, 01:34 PM
Everything I've read says the standard big bang nucleosynthesis model predicts that 7Li should also have been produced, and in greater quantities than observed.

On the other hand....



"When the temperature dropped far below one billion degrees [three minutes after the big bang] this 'primordial nucleosynthesis' stopped and, according to the standard model, we should be left with roughly 25% helium by mass and 2 x 10-5 parts deuterium. It may seem like a miracle that astronomers in fact do measure about 25% helium in the real universe, but it is a miracle squared that they also measure something like 2 x 10-5 parts deuterium." -- Tony Rothman (http://en.wikipedia.org/wiki/Tony_Rothman)



To be sure, Dr. Rothman is not talking about religious 'miracles.' He's talking about how remarkable it is that calculations according to the standard model of particle physics applied to the model of a hot, dense, and quickly expanding universe match the observed measurements so closely.

Spaceman Spiff
2008-Nov-01, 02:46 AM
Everything I've read says the standard big bang nucleosynthesis model predicts that 7Li should also have been produced, and in greater quantities than observed.

Right. The Ned Wright Cosmology page on big bang nucleosynthesis has this figure, toward the bottom:


http://www.astro.ucla.edu/%7Ewright/BBNS-sm.gif

He hasn't updated this particular page in a few years, but the observations for each of the species fall somewhere within the horizontal colored lines. The colored curves are the predictions of the elements' abundances, which are a function of the baryonic matter density parameter scaled by the square of the normalized Hubble parameter, (H_o/100)^2. The vertical grey bar indicates the measurement of this product, from for example WMAP (tiny intensity fluctuations in the cosmic background radiation angular power distribution). This vertical bar hits each theoretical curve where it crosses the horizontal bars indicating the observational constraints of the 2D, 4He, 3He, Li.

Now, given the fact that the theoretical uncertainties and observational error bars have shrunk, a strong tension between theory and observation is expected, and indeed this tension remains. See Gary Steigman's most recent review (http://arxiv.org/ftp/arxiv/papers/0712/0712.1100.pdf), in particular Figure 13 although you'll need to do a bit of reading to understand what is being plotted (the horizontal axis, eta, measures the ratio of baryons to photons scaled by 10^10, created in the first second of the "big bang"). In addition to its incredibly small abundance, another problem of measuring Lithium is that this element is readily destroyed ("astrated") in environments which have cycled gas through stars. At the present time, theory is way ahead of our ability to accurately measure these elemental abundances - but that's only because the theoretical uncertainties are so darned small!

Just think of how incredible it is that the theory is able to predict these abundances which differ by many orders of magnitude, not only getting in the ball park - but actually zeroing in.

timb
2008-Nov-01, 03:35 AM
Interesting link, thanks. A search on arxiv for "lithium problem" indicates that it is an active area of research. The discrepancy isn't large, and, as you say, the agreement between theory and observation is generally impressive.

tommac
2008-Nov-01, 08:31 PM
From my understanding the big bang does not say that something came from nothing but rather that everything was closer together at one point.

Everything always existed just REAL close together ( according to BB ).

I think the basis is just taking the expansion of the universe and a few other factors and working backwards in time to see where everything came from. If the universe is expanding then the universe is larger now than it was billions of years ago.


Help me with a question regarding the universe, please, although I'm not sure if I can ask this properly without straying into forbidden topics on this board. My question stems from a religious debate, and I'll try to keep this as neutral as possible.

One side of the debate argued that Something Created Everything out of Nothing. The other side argued that Everything came from Nothing.

My problem comes from the second argument, namely, Nothing Became Something. That's not how I see it, so I'm here to be corrected if need be.

As far back as we can detect, there has always been Something in the Universe. Eventually, we reach a point where the collapse of the laws of physics make everything opaque, so that we can't "see" anything. To view further back we have to extrapolate what we know about atoms and energy, role-playing as it were what they would do under certain conditions, to the point where we have a good idea of what happened within a tiny fraction of a second after the Big Bang. But never do we reach a point where there is nothing at all. What happened 'before' the Big Bang is impossible for anyone to know on two levels. First, no information survives from the prior existence of the singularity, and Second, there can't be a 'before' before Time began.

In other words, the Big Bang was not a Creation event but merely an Expansion event--an expansion of pre-existing matter and energy, albeit in a non-understandable form. I know that many people refer to the Big Bang as the Fires of Creation or whatever, but to my view, I see it as "creating" cookies by cooking dough in the oven, not spontaneously generating cookie molecules out of thin air.

So if someone asked me if I think that Everything came from Nothing, I would have to say, No I don't. I fall back on my default position that, as my hero Carl Sagan said, The Cosmos is all that is, and all that ever was, and all that ever will be.

Or am I just confused?

sohh_fly
2008-Nov-04, 04:50 PM
tommac

if the substance was always there, and then came together to condense, where did that original substance come from?

what troubles me with the BB is that question precisely.
since something was never nothing,this original matter could not have just come out of thin air.

this stuff is way to hard for me to understand.

also what would have caused the matter to condense before the BB took place?

thx guys
i always seek and mostly never find(lol)

Hornblower
2008-Nov-04, 09:05 PM
tommac

if the substance was always there, and then came together to condense, where did that original substance come from?

what troubles me with the BB is that question precisely.
since something was never nothing,this original matter could not have just come out of thin air.

this stuff is way to hard for me to understand.

also what would have caused the matter to condense before the BB took place?

thx guys
i always seek and mostly never find(lol)
We back-extrapolate in time with the best theory that can be developed from observations, and we eventually encounter that mathematical predicament commonly called a singularity. We don't know what the state of the universe was before then, or how it might be evolving. If we can unify gravity with quantum mechanics, we might eliminate the singularity at that point and learn something about what was happening earlier.

jamesabrown
2008-Nov-05, 01:43 PM
tommac

if the substance was always there, and then came together to condense, where did that original substance come from?



I ask that question myself, and I have to be careful with the answer. Asking "where does the stuff come from" smuggles in a space before space (as we know it) existed yet. It's so easy for me to think of the Big Bang as an firecracker exploding inside a room and the debris scatters to all corners of the room, which raises the questions, "Where did the firecracker come from, who put it there in the room, and who lit the fuse?"

There is no room. There is no firecracker warehouse where the firecracker "came from." If the Big Bang came from somewhere and exploded inside something, then you've assumed a place and time--but if we're talking about the entire universe, then that place and time has to be included. If everything is inside the firecracker, then the firecracker can't come from somewhere else--that somewhere else has to be inside the firecracker.

It's tough to understand, I admit, and I'm leery of people who don't stumble over it because they think they have an easy solution--"I know where the universe came from; X did it!"

Philosophers call the existence of the universe a Brute Fact, something that has to be accepted if we can have any coherent understanding about anything. I'm inclined to think that everyone accepts something as a Brute Fact--be it the universe, God, or something else. I'm inclined to accept for my own personal Brute Fact the universe, because the universe can be easily demonstrated. If something else is actually a better Brute Fact, then I'll need overwhelming evidence supporting it before I change my position.

sohh_fly
2008-Nov-14, 06:06 PM
ok but if the universe or space is the firecracker as mentioned,no problems with that but its the powder in the firecracker im wondering about,it had to be stuffed in there somehow for the explosion to occur.

so what im asking is that the universe and or the matter in it had to be born out of some kind of process.
the BB is just the result of the fuse being lit but where did the firecracker come from?
i'm guessing if it came from the factory, the factory wouldn't shut down after producing it's 1st product....so could there be more firecracker's ??

Cougar
2008-Nov-14, 06:15 PM
so what im asking is that the universe and or the matter in it had to be born out of some kind of process....

And nobody knows what that is. But quantum physics (http://en.wikipedia.org/wiki/Quantum_mechanics) provides a possible answer. Knock there, and the door will open.

closetgeek
2008-Nov-16, 04:34 PM
ok but if the universe or space is the firecracker as mentioned,no problems with that but its the powder in the firecracker im wondering about,it had to be stuffed in there somehow for the explosion to occur.

so what im asking is that the universe and or the matter in it had to be born out of some kind of process.
the BB is just the result of the fuse being lit but where did the firecracker come from?
i'm guessing if it came from the factory, the factory wouldn't shut down after producing it's 1st product....so could there be more firecracker's ??

It's the powder in the firecracker that has a lot of people still wondering. Just remember that BBT covers is an attempt to questions asked after the epoc but the TOE is still a work in progress.