Expansion of space but not of matter

[tommac]

I am still somewhat confused about space expanding without matter expanding and I wanted to ask a simple question.

If matter has not expanded along with space ( even a little bit ) then when the universe was the size of our solar system what was the deal? I mean obviously if the universe was the saize of our solar system I dont think that the earth and the sun could take up the same amount of space that it takes up now.

Was the space-time of the universe exapanded only in non-graviational points ??? I couldnt picture there being much non-gravitational space then.

Or was energy and matter much smaller then? I realize that it would be much hotter ...

[tusenfem]

ever though of reading a book on all these topics that you are questioning?

[tommac]

ever though of reading a book on all these topics that you are questioning?

I am not sure if they exist.

[speedfreek]

Oh they do, let me assure you. Or at least the books will show you how we think it all works and then you will understand why some questions make sense and some don't. In the meantime...

If matter has not expanded along with space ( even a little bit ) then when the universe was the size of our solar system what was the deal?

Well at that time the universe is theorised to have been filled with a superheated quark-gluon plasma. There were no atoms, as the temperature was far too high. But all the stuff that was in the universe then is what went on to become what is in the universe today. If you took all the matter and energy in our observable universe and compressed it down to the size of our solar system, you would end up with such a high temperature (over 10,000,000,000,000 Kelvin!) that all the atoms "dissolve" into a plasma.

Atoms couldn't form until the universe had cooled to around 3000 Kelvin, by which time our observable portion of the universe was over 40 million light years in radius.

Was the space-time of the universe exapanded only in non-graviational points ??? I couldnt picture there being much non-gravitational space then.

The expansion rate was so fast that gravity couldn't stop it, it could only slow it. As time went on the gravity slowed it until the universe was cool enough for atoms to form. These atoms didn't form uniformly, there were higher concentrations in some areas (as shown by the CMBR). As time went on even further and the total gravity continued to slow the expansion, the differences in matter density caused structures to start forming - gravity attracted more atoms to the areas of higher density, creating areas of lower density. In the end the higher density areas became stars and galaxies. So in the areas where the galaxies formed the local gravity finally beat the expansion and held things together, but in the less dense areas between the galaxies the expansion won out and moved the galaxies further apart.

We were expecting to find that the expansion had continued to slow down until the present day, but we got a surprise and found that something over 6 billion years ago the rate of expansion started to accelerate instead.

Or was energy and matter much smaller then? I realize that it would be much hotter ...

You got the hotter bit right. Energy and matter were simply compressed into a smaller area where area things were a lot more energetic than anywhere today!

[tommac]

Why do you believe that to be true? Because you are trying to see in the current universal conditions what the unverse would need to be like in order to be that small, yet all of the energy conserved. Right?

Ok I will follow your ( and I admit mainstream logic )

Now when the universe was that size, regardless that there was no mass and just plasma, the gravitational field must have been intense. At that point if space-time was expanding. It would have needed to have a force ( again maybe the wrong word ) greater than the compression of space-time by the gravity that energy produced. I would assume there was no vacuum of space back then. The cosmological constant at that time would have had to been exponentially larger than it is now. Since the force ( again different units than regular force ) would have been so strong that it would have overpowered the desire for energy and mass to contract space-time. I assume the energy waves would have redshifted. Energy would decrease as it redshifted meaning that energy itself was being stretched along with space-time. It seems that there would be a natural tendency to cool and I guess entropy would be linked to the expansion of space-time as a cooling mechinism.


What do you propose slowed the expansion of space-time? Or is the expansion DEFINED by the average density in the universe. So that for every bit of mass there is an equal amount of anti-mass ( cosmological-constant vacuum ) So that the universe as a whole keeps space-time constant.

Oh they do, let me assure you. Or at least the books will show you how we think it all works and then you will understand why some questions make sense and some don't. In the meantime...




Well at that time the universe is theorised to have been filled with a superheated quark-gluon plasma. There were no atoms, as the temperature was far too high. But all the stuff that was in the universe then is what went on to become what is in the universe today. If you took all the matter and energy in our observable universe and compressed it down to the size of our solar system, you would end up with such a high temperature (over 10,000,000,000,000 Kelvin!) that all the atoms "dissolve" into a plasma.

Atoms couldn't form until the universe had cooled to around 3000 Kelvin, by which time our observable portion of the universe was over 40 million light years in radius.




The expansion rate was so fast that gravity couldn't stop it, it could only slow it. As time went on the gravity slowed it until the universe was cool enough for atoms to form. These atoms didn't form uniformly, there were higher concentrations in some areas (as shown by the CMBR). As time went on even further and the total gravity continued to slow the expansion, the differences in matter density caused structures to start forming - gravity attracted more atoms to the areas of higher density, creating areas of lower density. In the end the higher density areas became stars and galaxies. So in the areas where the galaxies formed the local gravity finally beat the expansion and held things together, but in the less dense areas between the galaxies the expansion won out and moved the galaxies further apart.

We were expecting to find that the expansion had continued to slow down until the present day, but we got a surprise and found that something over 6 billion years ago the rate of expansion started to accelerate instead.




You got the hotter bit right. Energy and matter were simply compressed into a smaller area where area things were a lot more energetic than anywhere today!

[tommac]

The CMBR to me seems like reading tea leaves or ink drops ... basically we had a theory then looked at CMBR as evidence and saw something. However it does not prove the theory and if the theory is wrong then CMBR could just be random right? I mean what is the link where CMBR proves the BB ?

Oh they do, let me assure you. Or at least the books will show you how we think it all works and then you will understand why some questions make sense and some don't. In the meantime...




Well at that time the universe is theorised to have been filled with a superheated quark-gluon plasma. There were no atoms, as the temperature was far too high. But all the stuff that was in the universe then is what went on to become what is in the universe today. If you took all the matter and energy in our observable universe and compressed it down to the size of our solar system, you would end up with such a high temperature (over 10,000,000,000,000 Kelvin!) that all the atoms "dissolve" into a plasma.

Atoms couldn't form until the universe had cooled to around 3000 Kelvin, by which time our observable portion of the universe was over 40 million light years in radius.




The expansion rate was so fast that gravity couldn't stop it, it could only slow it. As time went on the gravity slowed it until the universe was cool enough for atoms to form. These atoms didn't form uniformly, there were higher concentrations in some areas (as shown by the CMBR). As time went on even further and the total gravity continued to slow the expansion, the differences in matter density caused structures to start forming - gravity attracted more atoms to the areas of higher density, creating areas of lower density. In the end the higher density areas became stars and galaxies. So in the areas where the galaxies formed the local gravity finally beat the expansion and held things together, but in the less dense areas between the galaxies the expansion won out and moved the galaxies further apart.

We were expecting to find that the expansion had continued to slow down until the present day, but we got a surprise and found that something over 6 billion years ago the rate of expansion started to accelerate instead.




You got the hotter bit right. Energy and matter were simply compressed into a smaller area where area things were a lot more energetic than anywhere today!

[Neverfly]

Why do you believe that to be true? Because you are trying to see in the current universal conditions what the unverse would need to be like in order to be that small, yet all of the energy conserved. Right?

Ok I will follow your ( and I admit mainstream logic )

There is much much more to it than 'mainstream logic'...

What do you propose slowed the expansion of space-time? Or is the expansion DEFINED by the average density in the universe. So that for every bit of mass there is an equal amount of anti-mass ( cosmological-constant vacuum ) So that the universe as a whole keeps space-time constant.

Say wha?

[captain swoop]

Why not go to a library and get a book on Cosmology, read it and if you still have questions come back and ask them.

[tommac]

Why not go to a library and get a book on Cosmology, read it and if you still have questions come back and ask them.

why do I need to get a book on cosmology when I studied at : The Lab

[tommac]

Say wha?

Sorry dove into ATM ...
Could it at all be possible that the expansion of the universe is equal to the compression of the universe near mass. Could those two effects be equal?
Again the thought is that a black hole contracts space-time. How much volume of vacuum would we need to equal the amount of contraction that a supermassive blackhole contracts, at the current rate of expansion in the vacuum of space.

ugg ... words are getting in my way.
If we drew a sphere around a black hole at what point would the expansion of the universe and the gravitational contraction of space time be at equalibrium?
Then could we figure out the total contraction of time-space relative to the equilibrium point of the black hole?
Then could we figure out the voume of vacuum that it would take to expand so that the sum of the vacuum + the area around the black hole is 0 space time expansion.

[cosmocrazy]

Why do you believe that to be true? Because you are trying to see in the current universal conditions what the universe would need to be like in order to be that small, yet all of the energy conserved. Right?

I think another thing to consider is your definition of size. Our concept of size is dependent on spacial dimensions. I,m sure i read that at the beginning when this plasma energy was the universe then space as we know it did not exist. Therefore it did not have a definitive size as we conceive it.

[tommac]

I think another thing to consider is your definition of size. Our concept of size is dependent on spacial dimensions. I,m sure i read that at the beginning when this plasma energy was the universe then space as we know it did not exist. Therefore it did not have a definitive size as we conceive it.

if that is the case then how could it expand or inflate?

[Neverfly]

If we drew a sphere around a black hole at what point would the expansion of the universe and the gravitational contraction of space time be at equalibrium?

This is the first question I have seen you ask yet that actually makes complete sense!

You put it into simple terms too- without all the fancy sounding word salad.

But first, I think what needs to be covered is :
Why is the Universe Not Expanding in Local space?

Read the lnks Several other members have given- including the FAQ I gave you.

ETA: Reason being, it's like you are skipping chapters in a book- jumping to the next chapter without reading the previous one...

[speedfreek]

Now when the universe was that size, regardless that there was no mass and just plasma, the gravitational field must have been intense.

And so would all the other forces have been. They might even have all been unified. Gravity is the weakest of the forces.

At that point if space-time was expanding. It would have needed to have a force ( again maybe the wrong word ) greater than the compression of space-time by the gravity that energy produced.

Gravity does not compress space-time, it curves it. Inflationary theory provides us with conditions in the early universe where, for a fleeting instant, a Higgs field provides a force like repulsive gravity but to an order up to 10^100 times larger than the value Einstein put on his cosmological constant. Then the Higgs field (known as an inflaton field) rapidly dropped towards zero allowing normal gravity to take hold but it was already too late to do anything but slow down something already huge and expanding at such a high rate.

I am afraid I got lost with the rest of your post around about the time you mentioned redshifted energy waves.

[cosmocrazy]

if that is the case then how could it expand or inflate?

I don't know the answer to that one. But why would it just suddenly do either? as mentioned already on this thread the 4 forces are assumed to be unified into 1 our current laws of physics do not hold up at this point in the universe's life so neither should our definitions of size and space.

[tommac]

Gravity does not compress space-time, it curves it.

Can you explain? I thought the curve of space-time was due to compression. The area nearest to the mass has shorter distances. so as something comes near it it will tend to move towards the massive object. Also spaces are shorter and times are slower near the massive object.

Did I just make that up? ( who knows )

[yawyaw]

The redshift is mis-understood. The universe is not expanding it is in equilibrium. The redshift is an indicator of the equilibrium. The mathematics is this:
Gravitational energy E= -mu/R + mcv the central forces are two: mv^2/R - mcDel.v.

The first force is the centripetal gravitational force and the negative force is the centrifugal force. When they sum to zero there is equilibrium, thus:
mv^2/R =mcV/Rcos g this gives cos rv = v/c=z= sqrt(GM/Rc^2) the redshift! The redshift is positive when cos rv is positive or the angle between the radius to the center of gravity and the velocity v, rv, is within plus or minus 90 degrees, that means moving away form the center. The angle of the redshift is determined by the ratio of the gravitational velocity and the speed of light, cos rv = v/c.

The the redshift is zero if the angle is 90 degrees, no gravitational acceleration g. There is a blue shift if the the angle is greater than 90 degrees.

The redshift is evidence of the universe being stable and in equilibrium. The centripetal acceleration of gravity is balanced by the centrifugal (center fleeing) acceleration of the moving masses.

Newton and Einstein, developed their gravity Theory based on only the potential energy e=-mu/R and did not consider the vector energy mcv for E=-mu/R + mcv.

When both energies are considered, the universe follows conservation of energy and is in equilibrium. The Universe is thus bounded. Conservation of energy is the first derivative set to zero which is also the limit condition, the continuity condition and the equilibrium condition.

The size of the universe can be estimated. My numbers are Size Radius=158E24 m; Mass= 2.133E53 kg; Cycletime T=16.5 Billion Years; the Shape is likely that of a cuboctahedron, Buckminster Fullers Vector Equilibrium.

I derived this estimate from the Gravitational Constant G. At Equilibrium Condition relationship is GM/R^2= cv cos rv/R or GM/R=c^2 at the speed of light. This realtion using Einstein's E=mc^2 gives the Power of the Universe: GM/Rc^2=1=GE/RC^4=GF/c^4=GP/c^5 = 1 therefore P=c^5/G = 3645E49 watts!

I have published this work at lulu: The Universe is NOT Expanding.
http://www.lulu.com/content/1839449

[NEOWatcher]

Let me try to layman-ize it a bit.
Now; I don't pretend to know how to work with it, but I do know which direction my knowlege would need to go.

Look at the table on this description of fundamental force. Yes; it's Wiki, but good enough for illustration purposes.

You see that there is a range for each force, and a formula for the strength of that force based on distance.

If we take two objects at a specified distance apart, we can compute the effect of the forces on each other, and determine a ratio between those forces. Now; we change the distances. Not only do the forces change, but the ratio that the forces have also change, because they don't change in the same way.

Now relate that to the expansion of the universe. When the univers was much smaller Gravity was in a much lower "ratio" of the effects of the forces than the others. So; if the particles were close enough, the strong Nuclear force would be 38 magnitudes stronger than gravity. Pull them apart slightly, then the strong force actually disappears.

Using those values and formulas, scientists can determine what's happening at the different sizes of the universe.

[tommac]

Wow ... great post!!!

The redshift is mis-understood. The universe is not expanding it is in equilibrium. The redshift is an indicator of the equilibrium. The mathematics is this:
Gravitational energy E= -mu/R + mcv the central forces are two: mv^2/R - mcDel.v.

The first force is the centripetal gravitational force and the negative force is the centrifugal force. When they sum to zero there is equilibrium, thus:
mv^2/R =mcV/Rcos g this gives cos rv = v/c=z= sqrt(GM/Rc^2) the redshift! The redshift is positive when cos rv is positive or the angle between the radius to the center of gravity and the velocity v, rv, is within plus or minus 90 degrees, that means moving away form the center. The angle of the redshift is determined by the ratio of the gravitational velocity and the speed of light, cos rv = v/c.

The the redshift is zero if the angle is 90 degrees, no gravitational acceleration g. There is a blue shift if the the angle is greater than 90 degrees.

The redshift is evidence of the universe being stable and in equilibrium. The centripetal acceleration of gravity is balanced by the centrifugal (center fleeing) acceleration of the moving masses.

Newton and Einstein, developed their gravity Theory based on only the potential energy e=-mu/R and did not consider the vector energy mcv for E=-mu/R + mcv.

When both energies are considered, the universe follows conservation of energy and is in equilibrium. The Universe is thus bounded. Conservation of energy is the first derivative set to zero which is also the limit condition, the continuity condition and the equilibrium condition.

The size of the universe can be estimated. My numbers are Size Radius=158E24 m; Mass= 2.133E53 kg; Cycletime T=16.5 Billion Years; the Shape is likely that of a cuboctahedron, Buckminster Fullers Vector Equilibrium.

I derived this estimate from the Gravitational Constant G. At Equilibrium Condition relationship is GM/R^2= cv cos rv/R or GM/R=c^2 at the speed of light. This realtion using Einstein's E=mc^2 gives the Power of the Universe: GM/Rc^2=1=GE/RC^4=GF/c^4=GP/c^5 = 1 therefore P=c^5/G = 3645E49 watts!

I have published this work at lulu: The Universe is NOT Expanding.
http://www.lulu.com/content/1839449

[tommac]

Is this stuff moving apart from each other or is this regarding the expansion of space-time. I get what you are saying but the part that I am questioning is the expansion of the fabric of space time itself not just the general repulsion of matter / energy away from each other.

Let me try to layman-ize it a bit.
Now; I don't pretend to know how to work with it, but I do know which direction my knowlege would need to go.

Look at the table on this description of fundamental force. Yes; it's Wiki, but good enough for illustration purposes.

You see that there is a range for each force, and a formula for the strength of that force based on distance.

If we take two objects at a specified distance apart, we can compute the effect of the forces on each other, and determine a ratio between those forces. Now; we change the distances. Not only do the forces change, but the ratio that the forces have also change, because they don't change in the same way.

Now relate that to the expansion of the universe. When the univers was much smaller Gravity was in a much lower "ratio" of the effects of the forces than the others. So; if the particles were close enough, the strong Nuclear force would be 38 magnitudes stronger than gravity. Pull them apart slightly, then the strong force actually disappears.

Using those values and formulas, scientists can determine what's happening at the different sizes of the universe.

[NEOWatcher]

Is this stuff moving apart from each other or is this regarding the expansion of space-time...

I was elaborating more of what Speedfreek did in #14 in response to your continued mentioning of gravity without the others in relation to the BB.

I get what you are saying but the part that I am questioning is the expansion of the fabric of space time itself not just the general repulsion of matter / energy away from each other.

Part of my problem is that I don't understand your impression of space-time.
I can sympathize with a non-scientific or lay perspective of understanding, but there is enough vagueness in your useage that I don't know where to begin.
The way I see it is that matter and energy are what defines the fabric of space time. So as the components expand or change, or do whatever they do in the world of physics, space time will have been changed.

[speedfreek]

Can you explain? I thought the curve of space-time was due to compression. The area nearest to the mass has shorter distances. so as something comes near it it will tend to move towards the massive object. Also spaces are shorter and times are slower near the massive object.

Did I just make that up? ( who knows )

Grant has already explained this far better than I ever could. I would link to the post but you posted in so many threads it would take me too long to find it again.

"Matter tells space how to curve, space tells matter how to move," - John Archibald Wheeler

[Tim Thompson]

The CMBR to me seems like reading tea leaves or ink drops ... basically we had a theory then looked at CMBR as evidence and saw something.

If you actually read & study nothing, if all you do is "chat", then what is the weight of "it seems to me"? That which "seems" and that which "is" are two entirely different things. After all, as you said elsewhere ...

OK I dont understand BB. I admit it.

So, where does the "it seems" come from? How do you decide, for yourself, what "seems" to you the way things should be?

However it does not prove the theory and if the theory is wrong then CMBR could just be random right?

Any theory could be wrong, but it does require some weight of observational evidence to falsify a theory. That evidence is not on the table, as far as standard big bang cosmology is concerned. As for the CMB being "random", absolutely no chance of that. For one thing, the spectral energy density of the CMB, in all directions, is highly no random. More specifically, it is a thermal spectrum consistent with Planck's Law (Mather, et al, 1994; Wright, et al., 2004). This is not only a prediction of big bang cosmology, but a necessary consequence of standard big bang cosmology.

Furthermore, while it might seem to you that analyzing the CMB is "like reading tea leaves or ink drops", it certainly is not. Again, intuition & seeming just don't count. There is no substitute for specific knowledge. The power spectrum of the spots on the CMB sky is not random, even though it may look that way to you. The pattern you see is in fact a wave interference pattern on the sky, and properties of the pattern are meaningful, not random, in the context of big bang cosmology. See, i.e., Fixsen, et al., 1997; Fixsen, 2003; Kuo, et al., 2007. Also see Ned Wright's CMB Anisotropy Page and /or Wayne Hu's Introduction to the CMB page.

I mean what is the link where CMBR proves the BB?

I have already explained that to you. The explanation also shows that the CMB was predicted before it was observed, and that too answers the question you ask above, "what is the link where CMBR proves the BB?" So, did you read the post? Did you ignore it? Did you simply forget that I had already answered your question? is it worth communicating with you at all? I mean, I try to always present real science & good information, but if you are not even going to pay attention, should I just find something better to do?

[zerocold]

The tommac threads are in teresting, but should be moved to "questions and answers" forum

[tommac]

OK so space-time changes.
Do you agree that if you have one meter of space and it gets compressed. That regardless of before or after the compression the speed of light will travel at c? Now can you see a unit of space the relatively doesnt change ... but gets a red shift because it has expanded or a blue shift as it contracted? This contraction can not be seen locally but only from a distant observer. for someone inside the meter is still a meter. If you look at light travelling throught that larger meter from the external world you would see light still travelling at c. Do you agree that in order for light to be c for the external observer and the internal observer that time would also have to be compressed or expanded along with the space?


So if we were in a part of space that was not gravitaionally bound ... the space around us would expand. Now I used to strongly believe ... but am being convinced otherwise ... but still not fully convinced ... that I would also expand along with the space that i was in. The reason I believe(d) this is that if there was an expansion of both space-time and my body was not included in that expansion then I am not sure how neurons could fire or the electrons would work as i would have shrunk and slowed down ... relative to the ruler/clock ...

I think I would be slightly larger in the vacuum of space than I would be on the earth, but when I went back to earth I would return to normal size. Again ... I have partially given up on all of this but not fully. As I cant picture a space expanding without the stuff inside of it expanding.

Also time it space would move a little more quickly than it moves on the earth.

Now when I say space-time contracting / expanding ... I mean relatively ( from inside that space ) nothing is happening. Externally ( from a place that is not being contracted / expanded ) you will notice the expansion.

Now for the redshift. Do you agree that if space is expanded that light would have to travel further to get to us even though from space view point the distance has not changed? Now this is another point ... that I am learning about ... if earth is not effected by the universal expansion and the space between the earth and a distant galaxy is then from earth things will appear more distant. If the earth is effected by the expansion of the universe then there is no real distance change between us and the furthest visible galaxy. However we would still see the same redshift as the redshift happens with the expansion of space and can be seen either from within the expanding part or external.


Now take a black hole. I believe that as the black hole is approached that space-time contracts. For things close to the black hole time is moving very slowly meaning that events happening externally are wizzing by. I also belive that matter is contracted.

As one is sucked into the black hole ... they would appear to be spaghettified. However the observer may not notice this effect. Their local time is moving so slowly and their relative space is contracting relative to them ... their perception of being devoured by a black hole can be much different than what an external observer may see ( like spaghettification ).

Now about the BB ...
I dont like the logical steps that we go through to conclude that the big bang must have happened. Firstly we cant logically go back to the moment it happened.

Secondly depending on how space-time is contracting and expanding there would be a much differerent result in the extrapolation backwards.

Thirdly I am not sure that the backwards logic of painting the picture of what happened in the past ... really would work moving in forward time

Fourthly there could be a steady state type of universe that could also work with the evidence at hand ... mainly red shift and CMBR although I admit there is not a theory that works ... but this doesnt mean that there is not one it just means that we have not explored every possible universal theory.

I was elaborating more of what Speedfreek did in #14 in response to your continued mentioning of gravity without the others in relation to the BB.


Part of my problem is that I don't understand your impression of space-time.
I can sympathize with a non-scientific or lay perspective of understanding, but there is enough vagueness in your useage that I don't know where to begin.
The way I see it is that matter and energy are what defines the fabric of space time. So as the components expand or change, or do whatever they do in the world of physics, space time will have been changed.

[Tim Thompson]

Do you agree that in order for light to be c for the external observer and the internal observer that time would also have to be compressed or expanded along with the space?

No.

Now when I say space-time contracting / expanding ... I mean relatively ( from inside that space ) nothing is happening. Externally ( from a place that is not being contracted / expanded ) you will notice the expansion.

This is very contrary to standard cosmology.

Do you agree that if space is expanded that light would have to travel further to get to us even though from space view point the distance has not changed?

No.

I believe that as the black hole is approached that space-time contracts.

General relativity tells us that spacetime is more strongly curved close to a black hole, but not contracted.

For things close to the black hole time is moving very slowly meaning that events happening externally are wizzing by.

Indeed, general relativity tells us that clocks in stronger gravitational potentials appear to tick more slowly relative to clocks in weaker gravitational potentials.

As one is sucked into the black hole ... they would appear to be spaghettified. However the observer may not notice this effect. Their local time is moving so slowly and their relative space is contracting relative to them ... their perception of being devoured by a black hole can be much different than what an external observer may see ( like spaghettification ).

This is not consistent with general relativity; an outside observer would see the clock in the strong gravitational potential as ticking slow compared to their own clock, in a weaker gravitational potential. However, the local observer in the strong gravitational potential will observe time to move at normal speed. Hence, they will certainly notice spaghettification, as long as they are able to. It is from the point of view of the distant observer, who does see the close in clock tick slowly, that spaghettification will appear in slow motion.

I dont like the logical steps that we go through to conclude that the big bang must have happened.

That's your privilege, but would it not make sense to actually know what those logical steps are, before you decide yu don't like them?

Firstly we cant logically go back to the moment it happened.

This is a totally irrelevant point. In fact, this kind of thinking invalidates most, if not all of science. We can't literally go to M31, but we can see it, and we can make inferences about it, based on what we see. That is the real point of all science. it is all about making inference about what we observe. Cosmology works the same way. We can see the universe in amazing detail, and we can make inferences based on what we see.

Secondly depending on how space-time is contracting and expanding there would be a much differerent result in the extrapolation backwards.

Actually, no. Observation reveals the expansion history of the universe. Assuming that the redshifts are generated by the expansion of the universe, observation reveals a unique (in other words, one and only one) expansion history, with uncertainty limited primarily by observational uncertainty, not theoretical uncertainty (i.e, Shafieloo, 2007; Brustein & Levy, 2006; Linder, 2003).

Thirdly I am not sure that the backwards logic of painting the picture of what happened in the past ... really would work moving in forward time

Specifically, why not? If I run a movie backwards, and then forwards again, does it not look the same the 2nd (or 3rd or 4th or ...) time forward as it did the first time? Just as there is one & only one movie, so there is one and only one universe (that we can see). Why should the universe be any different? We can see the history of the universe laid out before us in redshift space, just as we can watch the movie from beginning (almost) to the end. So we should be logically just as able to require backwards & forwards for the universe to work much the same as for the movie.

Fourthly there could be a steady state type of universe that could also work with the evidence at hand ... mainly red shift and CMBR although I admit there is not a theory that works ... but this doesnt mean that there is not one it just means that we have not explored every possible universal theory.

I don't get it. You think that scientists should not adopt any theory at all, until they have exhausted all possible theories? I don't know what you are trying to say. But I do know that all cosmological theories need to be consistent with observation, and consistent with the laws of physics as we know them (or testable extensions thereof). That certainly is true for big bang cosmology, so what's the problem?

[tommac]

I have read all of these posts and read all of the links and some of the books that people recomended here and still do not see enough proof.
I dont really care what scientist believe. So if they want to believe in BB then I am cool with that.

No.



This is very contrary to standard cosmology.


No.


General relativity tells us that spacetime is more strongly curved close to a black hole, but not contracted.


Indeed, general relativity tells us that clocks in stronger gravitational potentials appear to tick more slowly relative to clocks in weaker gravitational potentials.


This is not consistent with general relativity; an outside observer would see the clock in the strong gravitational potential as ticking slow compared to their own clock, in a weaker gravitational potential. However, the local observer in the strong gravitational potential will observe time to move at normal speed. Hence, they will certainly notice spaghettification, as long as they are able to. It is from the point of view of the distant observer, who does see the close in clock tick slowly, that spaghettification will appear in slow motion.


That's your privilege, but would it not make sense to actually know what those logical steps are, before you decide yu don't like them?


This is a totally irrelevant point. In fact, this kind of thinking invalidates most, if not all of science. We can't literally go to M31, but we can see it, and we can make inferences about it, based on what we see. That is the real point of all science. it is all about making inference about what we observe. Cosmology works the same way. We can see the universe in amazing detail, and we can make inferences based on what we see.


Actually, no. Observation reveals the expansion history of the universe. Assuming that the redshifts are generated by the expansion of the universe, observation reveals a unique (in other words, one and only one) expansion history, with uncertainty limited primarily by observational uncertainty, not theoretical uncertainty (i.e, Shafieloo, 2007; Brustein & Levy, 2006; Linder, 2003).


Specifically, why not? If I run a movie backwards, and then forwards again, does it not look the same the 2nd (or 3rd or 4th or ...) time forward as it did the first time? Just as there is one & only one movie, so there is one and only one universe (that we can see). Why should the universe be any different? We can see the history of the universe laid out before us in redshift space, just as we can watch the movie from beginning (almost) to the end. So we should be logically just as able to require backwards & forwards for the universe to work much the same as for the movie.


I don't get it. You think that scientists should not adopt any theory at all, until they have exhausted all possible theories? I don't know what you are trying to say. But I do know that all cosmological theories need to be consistent with observation, and consistent with the laws of physics as we know them (or testable extensions thereof). That certainly is true for big bang cosmology, so what's the problem?

[Neverfly]

I have read all of these posts and read all of the links and some of the books that people recomended here and still do not see enough proof.

I'm calling you out.. I find this claim HIGHLY UNLIKELY

I dont really care what scientist believe. So if they want to believe in BB then I am cool with that.

It is Not about Belief.

I do not 'believe in' or 'disbelieve in' the BBT. I see the observation.s I see the evidence. I see weirdness. I do not have faith in it. I do not assign it belief.
I see weird observations that tell me "this"___.

It is not the same thing.

[mc^2]

tommac,

I think I see where you're coming from, but I think you might be clinging to popularised notions of "expanding space". This is not entirely your fault, as terms such as "expansion of space" do not properly convey what is really being explained by General Relativity.

When thinking about the expansion of the universe, try to let go of your impression of space as a "fabric"... our everyday analogue to this would be something like a rubber sheet or a balloon with grid lines drawn on it. While such concepts are useful to assist us in visualising distortion of space, it can become misleading if you assume that your unit of length (let's say, a metre) is defined as the distance between two points on the grid. For, if your balloon expands or contracts, you naturally might assume that your metre is expanding or contracting. Not so!

This is why since 1983 we define a metre as the the length of the path travelled by light in vacuum during a time interval of 1/299,792,458 of a second. This is important, as all our observations and measurements are then tied to the ticking of our local clocks. Remember, in Relativity there are no privileged (god-like) observers - everything that you can measure is relative to your clock and your ruler.

In fact the "balloon" or "rubber sheet" analogies don't really do General Relativity much justice at all, but as aids they're a starting point.

Quite simply put, as the universe expands, more space is being "created" as time goes by. It's easy to draw you a simple diagram.

t0: (You)---------->(distant galaxy)

t1: (You)-------------------->(distant galaxy)

Where the "-" represents a number of meters, lightyears, or whatever unit you might choose to measure distance between yourself and a distant galaxy, and t0 and t1 are two different times at which you make your distance measurements, measured by your clock.

As you can see, your unit of length doesn't increase. The number of units does!

So we see that there is a increase in distance between you and the distant galaxy for every tick of your clock.

This means that the light coming from the distant galaxy is subject to a doppler-like effect.... As the distant galaxy moves away, its light has more distance to travel to you, so the time between "wave crests" of light arriving to you gets longer and longer, because the light is still travelling at the same velocity. The wavelength of light increases, the frequency decreases, yet the velocity remains the same, hence you get the red-shift effect.

It follows from this that your point of reference (i.e. you) doesn't get bigger or smaller. The expansion is what we call intrinsic to space itself. This expansion occurs over time as measured by the ticks of your clock.

The expansion of the universe only has a measurable effect on supergalactic scales... where the expansion meets little resistance to gravitational, atomic and electromagnetic forces. At our scales of things, these forces easily overcome the expansion of space by truly stupendous factors, hence matter does not expand with space.

Now is a good time to go hit those books.

Cheers.

[NEOWatcher]

I have read all of these posts and read all of the links and some of the books that people recomended here and still do not see enough proof.

Ok; so why don't you read all of the books?
And; you not only have to read them, you must be able to comprehend them, and you need to know the science they used in thier references.

Tim suggested 3 references in that very post you responded to. While I can believe you read the links within that 7 minute time frame, there is no way you have read the material that those links describe.

I dont really care what scientist believe. So if they want to believe in BB then I am cool with that.

If you are cool with that, then why do your posts sound like you are trying to change thier belief*?

*Not the proper word, but I'm continuing with the same context.