This is my first post. I couldn't find the introductions section. Hope that's not a bad sign.

Greeting brodix. Welcome to BAUT. 'c' does, in a sense, increase as space expands. This does not violate GR because photons sacrifice energy [redshift] in the process. It does not violate SR because time dilation conserves the distance velocity relationship between remote observers.

Thanatos,

Does that mean redshift is due to recessional velocity, or negative curvature?

Moved from ATM section - welcome to BAUT, brodix!

Occam must be quite dizzy and his razor is reduced to a wet noodle.

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For those inclined to oppose human meddling with the structure of the universe or the composition and configuration of objects and groups of objects within the universe, consider:
Whether there is a limit to the magnitude of a modulation of chaos below which order remains invariant? Or, is order but a fiction invented by perspectives applied over finite, however large, time intervals?

Nereid,

Thanks for the direction, but I'm being somewhat leading with these questions. Dipping my toe in the water and trying to find where the members of this forum are, with regards to their adherence to the Big Bang model.
If you wish, I could offer up some thoughts on the subject. For instance, if space is expanding due to recessional velocity, does that mean that when the universe was half its present dimension, the speed of light was half as fast as it is now? Otherwise it would seem the speed of light is relative to a more stable dimension of space then that proposed by Big Bang Theory, as based on the redshift of this light.

Welcome, Brodix...

You'll find that some like balloons, some like cake and some like to have their cake and eat it. But beware, there's sharks in the water (and ducks, IIRC)...

Q: Why doesn't c increase as space expands?

A: Why should c increase as space expands?

The questions & answers are always intimately connected to the model(s) that one chooses to describe the detailed physics of the universe, as well as its expansion history (if any). So, one might legitimately answer the question with the obvious counter question. Is there some reason we should expect c to increase as the universe expands? How about c decreasing as the universe expands (which is the way it behaves in the variable speed of light cosmology, advanced primarily by João Magueijo; i.e., Albrecht & Magueijo, 1999 and citations thereto).

And what exactly do you mean by "c" anyway? Do you mean the speed of light as measured by an observer in his own frame of rest? Do you mean the speed of light as a variable in the equations of general relativity? Do you mean the speed of light as a "constant" (or variable) of proportionality between space & time? They are all different, but all perfectly valid cosmological interpretations of c.

The original question really only makes sense in the context of some cosmological model. In standard big bang cosmology there is no need for c to vary at all, so it does not. It could be variable, there is nothing about general relativity that prevents it from being variable, it's just that things are a lot easier to understand & manipulate if it is not.

So, why do you think it should be variable? And are we heading back to ATM?

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The point of philosophy is to start with something so simple as not to seem worth stating, and to end with something so paradoxical that no one will believe it. -- Bertrand Russell

Originally the big bang model simply assumed the universe was expanding, but as galaxies were examined more closely, they were all redshifted directly away from us, with no other direction or flow, suggesting an expansion from some general region. Therefore the impression was that we were at the center of this expansion. The concept was amended to say that space itself was expanding, so that every point was receding from every other point at a rate proportional to distance and they have all started out as a singularity. My point is that the speed of light is 299,792,458 meters per second, so if space itself is expanding, and the meter is a measure of space, then it is expanding, so the speed of light should stay relative to this dimension, even though it is expanding. Of course, this would create a matrix effect and we wouldn't even be able to detect the expansion, but that is why it doesn't make sense to say that space is expanding, if our most basic measure of it is stable.

My theory is that radiation negatively curves space, just as mass positively curves space. So light which managed to travel across the universe, without falling in any gravitational wells, would have crossed a lot of negatively curved space and appear as though its source was moving away.
This idea first occured to me, many years ago, upon hearing that Omega should equal one. It seemed a convective cycle would be the most logical explanation for this. Like the diameter of both sides of the same coin being equal.
When mass collapses to a sufficent density, it ignites and radiates out the constituent energy, so if we can accept that mass causes space to be curved positively and radiation expands out from collapsed mass, wouldn't it be logical to assume that it causes space to be curved the other way?
We know mass collapses, we know it ignites and radiates out. The only part of the circle which is open is if this radiation eventually cools to the point of condensing back into mass. Obviously there is a big gap between photons and hydrogen, but physics has spent the last fifty years proposing and analysing a zoo of subatomic activity, from quarks and neutrinos to strings. Where do the strings representing light start to bind into those representing mass? E=mc2.
The 2.7k level of CMBR would amount to a dew point/phase transition and black holes would be the eye of the storm.
If the expansion of space is a vital property and not the residue of a singularity, then the closer measurements would be the more accurate, so the question of dark energy would be moot. This curvature is the cosmological constant that balances the force of gravity.
I'll let it go at this for the moment. (Got to pick up my daughter.)

It was because of Edwin Hubble's redshift findings that Lemaitre proposed his Big Bang theory, as it was later coined by Hoyle. Not the otherway around.

I don't think Lemaitre or others thought this way, but I would be curious if any evidence supports this idea.

I suspect otherwise, but I am, admittedly, pretty low on the totem pole.

Yes, per E=mc^2; photons have relativistic mass.

I don't think light contributes much to curvature.

My limited view has light appearing to us to redshift because we have gained in relative velocity with respect to the photon emitter due to expansion. This is a pure Doppler approach. The photon remains intact, similar to the fact galaxies and clusters are barely affected.

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Lighten up! This is a stellar board!

This is Questions and Answers. You should pick another section to promote your theory, probably Against the Mainstream.

Please, start a new topic in the right place.

Starting out your advocacy by asking a question -- especially when done to gauge where the audience is, not to actually get a question answered -- leads to topics that don't fit well anywhere.

Thanks

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It still does. That's the fundamental statement of the Big Bang model, yesterday, today, and always: the universe is expanding. How you choose to further describe that expansion in words depends entirely on your coordinate system (which in turn is a choice of picture, not a statement of reality).
Who said a meter is a measure of space? A meter is a measure of distance. Distances are increasing, that's what one means by saying the universe is expanding, and that's all one means. If the meter were to expand as well, then distances would not increase and the universe would not be expanding. You need to review the definitions of measurables used in physics before you can lay claim to any improvements.
No, that is why your incorrect interpretation of space expanding doesn't make sense.
OK, redshifts are not caused by curvature in space, they are caused by curvature in spacetime. Curvature in space depends on the coordinate system. It is becoming more and more customary to use a flat space to do cosmology, such that all the curvature, and all the redshift, comes from the time dimension.
It seems to me you are crossing the line from legitimate ATM into simple nonsense here, and continues in that vein.

[QUOTE=George;870118]It was because of Edwin Hubble's redshift findings that Lemaitre proposed his Big Bang theory, as it was later coined by Hoyle. Not the otherway around.

I don't think Lemaitre or others thought this way, but I would be curious if any evidence supports this idea.[quote]

I mashed a lot there, sorry it doesn't come out clear.

Then the speed of light is relative to a different dimension.

Comment in this week's New Scientist, on gravity, pointing out that below the temperature for super conducting, photons gain mass and electrons start binding. Interesting for my hypothosis that light radiation dropping below the level of CMBR might start condensing into mass.

If it was accepted, then I wouldn't be proposing it.

The problem with using the Doppler effect to describe this is that it doesn't imply expanding space, only increasing distance in fixed space. The train might be moving away, but the railroad tracks are not stretching. The speed of light amounts to the railroad tracks.
Why is it so easy to accept positively curved space, but negatively curved space is taboo?

This is Questions and Answers. You should pick another section to promote your theory, probably Against the Mainstream.

Please, start a new topic in the right place.

To be fair, he did start it in ATM but Nereid moved it to Q&A (see post 3.)

so if space itself is expanding, and the meter is a measure of space, then it is expanding, so the speed of light should stay relative to this dimension, even though it is expanding.

The metre's definition is based on the speed of light so regardless of what happens with space, c is fixed.

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Apollo: The History and the Hoax
Enter the World of Athran

Sorry for the confusion. I'm a little gunshy. I've been avoiding this topic for some time, but find myself drawn into it discussing other things.

If it doesn't get switched back, I guess I've have to put something together.

[QUOTE=Ken G;870176]It still does. That's the fundamental statement of the Big Bang model, yesterday, today, and always: the universe is expanding. How you choose to further describe that expansion in words depends entirely on your coordinate system (which in turn is a choice of picture, not a statement of reality).[quote]

The speed of light is a rather fundamental parameter of reality. It's not just some abstraction.

The reason why it's described as expanding space and not an expansion in space is because all the other galaxies are redshifted directly away from us, with no hint of motion in other directions, as if it were an expansion from another point, so the impression was that we were the center. The concept that space itself was expanding presumably meant that every point was the center. That's why the fact that our most basic measure of space, C, isn't growing is a problem.

I'm not saying space is expanding. I'm saying that in the areas of space where gravity doesn't prevail, radiation causes it to be negatively expand.

Obviously. We call it curved because nothing travels in a flat line, or at a completely constant rate.

So saying that light causes space(time) to be negatively curved is more nonsensical then saying the universe began at a point, expanded to many times its visible size in a fraction of a moment, slowed immediately(what was the breaking mechanism for the momentum of Inflation), is speeding up again and is 96% invisible, is perfectly sensible? How about the virgin birth? I've got some stock in a bridge up in New York, cheap! Don't get these guys to do your taxes.

So saying that light causes space(time) to be negatively curved is more nonsensical then saying the universe began at a point, expanded to many times its visible size in a fraction of a moment, slowed immediately(what was the breaking mechanism for the momentum of Inflation), is speeding up again and is 96% invisible, is perfectly sensible? How about the virgin birth? I've got some stock in a bridge up in New York, cheap! Don't get these guys to do your taxes.

It would, if that was actually the current MS version of the BB, which it isn't. Perhaps you better do step one, go learn the current MS theory of the big bang (more like a big whoomph) and then come back and try again.

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Howling from the Shadows

It must be fun to lead a life completely unburdened by reality. --- JayUtah

You can't reason an irrational person out of an irrational belief. --- Noclevername

Apollo: The History and the Hoax
Enter the World of Athran

Usually I list it in miles because of that, but the site I googled it off of this time had it in meters and I was in a hurry. The point still stands, though.

Maybe it will get switched back.

Oh I forgot, it wasn't a virgin birth. They think there might have been previous universes. Sorry if I haven't kept up on the latest. Politics has been much more interesting lately.

I haven't seen the article but unless it is about a phase change in the Higgs Field, then mass is not temperature dependent.

Yes, I forgot this has now changed to a ATM discussion.

Not necessarily, there are problems with a fixed space approach including symmetry failure, I think. Also, absolute space was defeated by Einstein in favor of absolute spacetime. My view maintains the symmetry and accepts expansion.

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Lighten up! This is a stellar board!

Well isn't the mile defined in terms of metres?

Thread moved (back to) the ATM section.

brodix, if you'd like, I (or another mod) could close this thread - temporarily? - while you take some time to gather your thoughts, read the rules, read some threads (in this ATM section, as well as the Astronomy and Q&A sections), etc.

Otherwise, please present your ATM idea ... and be prepared to defend that idea against challenges (from other BAUT members), answer direct, pertinent questions on that idea (as presented), ...

Only in an inertial reference frame. As Tim pointed out, the speed of light in GR is not a constant.

Your operating under a misconception here. In GR energy (which is what radiation is) and mass (which can be converted to energy terms by multiplying by c²) causes space-time curvature. Now whether or not that curvature is positive, negative, or near-flat (and it can be either of the three) is dependent on the energy density of a given volume.

It would also move through regions that are positively curved and also regions that are locally pretty much flat. So what? Can your idea quantify exactly how much of a redshift we should see depending on the path length of such a photon?

This is a one of the better examples of word salad.

It does? You have the references and math to back up this statement, right?

There are a lot of things in the universe that are quite counter-intuitive. Whether or not something is logical depends on the internal consistency of the model you are using.

Actually it would be more logical to actually study some basic physics, some advanced physics, some advanced math and then actually study General Relativity. At least then you might actually understand the relationship between radiation/mass and space-time curvature and whether that curvature is positive, negative, or flat.

Actually, it appears that mass collapses to a singularity, forming something that pretty much captures everything falling in and doesn't radiate much of anything out (A black hole).

How exactly do you define the cosmological constant mathematically, in your idea? And, in your idea is the cosmological constant positive or negative and which calculations led you to this conclusion?

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Neptune- The original Dark Matter.

The author feels that this technique of deliberately lying will actually make it easier for you to learn the ideas. - Donald Knuth

It's about the gravitational drag of superconducters.


Space(time) may not be absolute, but while it fluctuates off C, according to circumstance, there has been no suggestion that it changes along with the expansion of space, so it would seem dependent on another dimension of space then that propsed by BBT.

Actually it was originally the distance a horse could gallop before tiring. I forget what's the most current definition, but measuring it against the meter is logical. Since the meter is a percentage of C, it shows that the speed of light is one of our most stable dimensions of space, so saying space expands, but that the speed of light doesn't increase accordingly poses a logical contradiction.

Off to work....

It is a thousand paces (a thousand times that your right foot steps on the ground while walking). Note the etymology.

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Forming opinions as we speak

Actually I'm taking the title of this section literally. It's name isn't, "alternative theories," but "against the mainstream." I've learned that coming up with ideas which don't fit the current paradigm is somewhat futile. Everyone assumes you are a crank and most of the ones who consider the argument focus on whatever loose ends there are and rarely are willing to consider whatever basic point you are trying to develop. (Not that this is bad. Frankly I've learned alot from arguing.) So rather then specifically offering my own ideas, I'm instead pulling a loose thread in mainstream theory. Which is, to repeat; How is it that we have a theory that says the universe and all the space it contains began at a point and is expanding at nearly the speed of light, all based on the redshift of the spectrum of light, yet apparently assume the speed at which this light crosses space is not increasing by the same rate?

Hopefully this approach is acceptable.

Just to take one part of the question at the end, in (my) bold (I'll address the other things in this post later):

First, the big bang theories do NOT say "the universe and all the space it contains began at a point"!

This is one of the most common misunderstandings that I see in posts in BAUT.

GR (General Relativity) and QM (Quantum Mechanics) are mutually incompatible in the Planck regime. This means that these two highly successful theories cannot both describe the nature of the universe 'before' (or 'during') the first Planck second.

Second, "expanding at nearly the speed of light" is either (another) misunderstanding, or just downright wrong. The 'speed of expansion' is a tricky thing to get a handle on, if only because 'distance' isn't at all like you intuitively understand it, here on Earth.

Third "all based on the redshift of the spectrum of light" seems to be referring to the Hubble distance-redshift relationship. If so, then you've somehow morphed just one observational pillar of the modern concordance model in cosmology into "all". The others are, as I'm sure you already know: the CMB (cosmic microwave backgroud, which is actually at least two, somewhat independent, tests); the primordial abundance of (light) nuclides; and the large scale structure of the (observed) universe.

Finally, and as has already been pointed out, "apparently assume the speed at which this light crosses space is not increasing by the same rate" is (yet another) misunderstanding of modern cosmology.

You see, scientists are incredibly conservative (in one sense) - they hate to abandon a good theory, unless there is very good reason to do so.

And what has this scientific conservatism got to do with your question?

Everything.

The "big bang theory" is 'just' the application of General Relativity (GR) to the universe as a whole. GR is one of the best theories we have - it has passed every test it has been subject to, with flying colours. And no alternative theory comes even remotely close to matching its record.

When you apply GR to a real universe, one which contains real protons, neutrons, and electrons, you get *the Hubble relationship; *the CMB; *the primordial abudance of light nuclides; *large scale structure just like what we observe.

So, in one sense, GR just passed another series of (four) tests, again with flying colours.

Or, if you prefer, your question is equivalent to "why do we think GR is a good theory, when it comes to describing the way the universe works?"

Can you see the connection? Do you understand why the two questions are essentially equivalent?

Yes, it varies, but not to the degree it would if the space it defines were expanding at the rates proposed by BBT. When the universe was half its current dimensions, was the speed of light half as fast?

This doesn't seem to be negating what I'm saying. Omega=1 means that the negative curvature of space is balanced by expansion. Within a gravity well, the curvature is positive. Therefore what's outside these wells is in inverse proprtion. All I'm saying is this is negative curvature.
When the idea first occurred to me, I thought in terms of the space being drawn into blackholes might be cycled through another dimension and coming out in the vacuum as vacuum fluctuation. It was in discussions on the NYTimes, Mysteries of the Universe forums, in the late nineties that a physicist out of Chicago pointed out that light was the logical medium, but when he came up with the idea, earlier in his career, an older colleague suggested that unless he wanted to seriously complicate his career, he'd be wise to support the standard model, not raise questions about it. I suppose that seems paranoid, but I've seen enough politics in enough other circumstances to understand how it can be.

Actually, since it would be an effect of radiation, it would also depend on the intensity of the radiation, as well: http://ucsdnews.ucsd.edu/newsrel/science/mcquasar.asp

Order is a function of perspective.

That is worth a chuckle. You are going to argue whether stars condense out of interstellar gas, until they ignite? We must be in different realities.

Such as whether reality is bottom up phenomenological, or top down ordered. Or both.

As the old saying goes, the more you know, the more you know you don't know.

There was a report about a year ago that black holes are not consuming very much matter. It came as a surprise, but it fit my thought that black holes are the eye of a gravitational storm and most of what happens is the mass collapsing to this point, by which most has burned up and radiated back out. There is the stream of electrons flowing out the poles, but that might explain where what does fall in goes out.
Remember the convective process is what defines the activity of planetary and stellar bodies, so it's just a fractal projection to use it to explain galactic activity.

Since it was originally proposed to balance gravity and maintain a steady state universe, the unmeasured part would be negative curvature. I originally came at this from a philosophic, then mathematical perspective.

Yes, the speed of light was half as fast and the distance light could travel in a year was also half as far so the length of a light year was half its present length. The standard length of a meter is defined as the distance light travels in a given length of time so the length of a meter would also be half as long. If the speed of light did not accelerate in perfect proportion to the radius of the universe, there would be a mixing of light with old light traveling slower than new light and deep space objects would appear blurred. Gravity causes a slowing of time and a dilation ‘shortening’ of space and these gravitational changes are the reason why light traveled slower in a smaller universe with a greater gravitational density. These same gravitational changes, as described in general relativity, make the speed of light appear the same for all observers. The speed of light may vary from one reference frame to another but all observers measure the speed of light as c in their own reference frame. If we could travel several billion years back in time to where the universe was half its current dimensions and light traveled at half its current speed, we would still measure c as being the same because the length of a meter would also be half its size. The same general relativistic effects that make the speed of light the same for all observers should also make the radius of the universe the same for all observers so I find your conclusion valid that we can never observe any change in the radius of the universe. Present estimates are that the universe has a radius of about 15 billion lightyears. A universe of half its current size should also appear to have a radius of 15 billion light years and universe with twice its present size should also have an observed radius of 15 billion light years. This means that our measurements for the radius of the universe based on Hubble recessional velocities are like a stopped clock… they can only be correct at two points in time. Once when the universe expands to 15 billion light years and again when the universe contracts to 15 billion light years. These are also the only two times when we can expect our theoretical and observational ducks to line up in a row. Present observations require the fudge factors of a faster than light inflationary period, dark matter, and dark energy, to make observations fit theory. A universe that is larger and older than 15 billion years can be explained without these corrections which suggests that we may have passed the 15 billion lightyear point without knowing it. Speculations about the true radius of the universe and its state of expansion are based on the presumption that we can describe the universe from a god like perspective ‘beyond’ the universe where we can watch it expand or contract. The only observations we have, or can ever have, are those made from within the universe where gravity rules and all of our observations are subject to the distortions of general relativity.

Gravity causes a positive curvature of space-time and there are many locations in deep space where the forces of gravity are in perfect balance so there may appear to be no gravity but gravity is everywhere. You may be far from any gravitational source but you still have billions of galaxies above and billions of galaxies below and that adds up to a large sum of gravity… perhaps the largest. The positive curvature of gravity is inescapable.