(my bold)

What is it (the "viable alternative")?

I'm not claiming expertise. In fact, I'd happily qualify as making up stories, if they, at the very least, help me to better understand what's going on. When I first started reading physics, thirty years ago, I had no further expectation. The idea which started me on this concept was a point Hawking made in his book, A Brief History of Time, that for the universe to be as stable as it is, Omega had to be very close to 1. Being a simple-minded sort, I immediately thought a convective cycle(rising heat/collapsing cold) would explain that relationship far more neatly then the anthropic principle. Given the level of the popsci I was reading at the time, the idea which first occurred to me was that mass and the space it defined were being drawn into black holes, into another dimension and re-emerging as vacuum fluctuation. This way, the expansion was integral to the space and not simply that everything was flying apart from a singularity. So that the further light traveled, the more expanding space it crossed, this compounded the effect, so that it eventually seemed as though the source was receding at the speed of light and this created a horizon line, beyond which light couldn't travel, creating a sphere of visibility. Someone with far more education pointed out that light made a perfectly good vehicle, so I dropped the other dimension.

I'm almost surprised at the number of occasions I've witnessed amateurs suggest some version of balanced relationship between this expansion of space and the contraction of gravity. One of the more memorable was on a local radio show(Mark Steiner, WYPR. Baltimore. The Hubble is run out of Johns Hopkins) It variably gets laughed off.


I thought a flat or open universe simply meant that it wouldn't contract back to a point?

If expansion is a property which is balanced by gravity and assuming all gravitational effect is currently in effect, it presumably would neutralize the expansion of space, so that the universe as a whole isn't getting any bigger, because these two effects cancel one another.

Pardon my ignorance, but could you give a thumbnail?

Obviously, or there would be no BBT. The idea is whether radiation/light is actually the source of the cosmological constant. I don't see it as disproving Einstein, but rather tying a couple of the loose ends to each other.

Yes, but first you have to figure out what causes it, before you can really figure out what it does.

I'm trying to tie the concept of convection to this larger process. In fact, convection would be an aspect of this larger process. Matter cools and falls until it does it heats up and rises. In the convection cycle, this energy would then cool down and fall back to earth. What would be the comparable aspect of the cosmic process? The light, having been redshifted off the chart.....to the mass which starts condensing out of the most ethereal intergalactic gases to eventually falling into the galactic vortex..... (story making any sense?)

In a cycle, like a wheel, one side tends to be the same diameter as the other.

IF it is space that is expanding lightwaves and not the galaxies flying apart, then the reason the furtherest galaxies appear to be receding at the speed of light is because the light from them has crossed the most space and the effect is compounded, so that the further light travels, the greater the multipler effect, thus the faster the source appears to be receding, NOT because these galaxies are traveling fastest because they are at the dawn of the universe and everything has been slowing down since then.

The additional expansion for which dark energy was proposed and has recently been shown to compare to the cosmological constant, means that something is augmenting the presumably slowing expansion, such that the space itself appears to be expanding. If it is a lensing effect and not the galaxies actually flying apart from one another, then you don't need the massive amount of energy required to actually be pushing them apart.

I like to read a lot and it wasn't something I noted down. Possibly it was on the Nature site. I get their email update. Would you have a link to the study of active black holes? It sounds interesting.

Part of the reason Inflation theory was proposed was to explain how the CMBR would be so even, at 2.7k, across the universe, when this would require information traveling faster then the speed of light. Possibly this level(2.7k) is due to a natural phase transition, such as the density above which some effect causes the radiation to start condensing into elemental mass.

Pretty much anything to do with the quantum realm.

My mistake.

Stories came long before the math. No story, no math. Quantum theorists have this notion that it's only the math that makes sense. It only means the story lays beyond their comprehension and they only see the highlights.

I said I wouldn't post to this thread again, and asked you to also not do that (instead, address all the remaining stuff in your promised new thread). Unfortunately, you answered again here - hence I have to come back again...

I have snipped quite a lot where we both simply repeated the same again and again; looked quite futile to me to continue that.


(1) I would say there is a difference between "machinery" and "mechanism".

(2) You claimed that Feynman was unsatisfaid with GR's description of gravity. But your quote above shows nothing like that. It does not even show that Feynman is unsatisfied with Newton's physics for giving no "machinery" - he simply notes that Newton gave no machniery - and also no one ever since.


Why do you think you can judge this better than physicists?


Stop boasting, start presenting your work, please. And, as I already mentioned: not only verbiage, please. Show some math, show some derivations, show quantitative agreement between the predictions of your model and the data.



Looks like a double standard to me. You don't make the same request ("I have to see it to believe it") for baryonic matter. You simply accept that quarks, gluons, muons, tauons etc. exist, although one could even in principle never "see" them directly.



Like I already suggested: you could have answered me in your new thread.


Does this "viable alternative" address all the pieces of evidence I mentioned? New thread, right?


You are confusing two things here: stating that Lambda measures the energy density of the vacuum, and calculating from Quantum Field Theory what that energy density should be. That the calculation gives a wildly different value
does not in the least imply that the original interpretation is wrong - only that the calculation is based on false premises. And everyone who ever attempted such a calculation essentially already knew that!

For being able to calculate the "energy density of the vacuum" from first principles, we first need a working quantum theory of gravity. Calculating that energy density using only the quantum field theories available today makes little sense.


No, that's news to me. Please elaborate (in the new thread, if you like).


You talk about "low blows", and then you write such a smear against thousands of scientists? Looks again like a double standard to me.


Lambda measures an energy density, not an energy. So per what volume is this millielectron-volt?




I didn't say that I know of such a method. I merely pointed out that we shouldn't simply assume that this never can be done, and use that assumption to dismiss dark energy as "unphysical".


In order to rule out other interpretations, I first have to know them. When will you start presenting yours? BTW, a reminder: please be quantitative!

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I notice you apparently simply dropped the argument about measuring the size of the galaxy with a light beam.

If you base these stories on known physics, no problem. If you simply make up stories which strongly contradict known physics, big problem.

And again, I can't follow you at all. How on earth should such a cycle explain the stability of the universe? How did you arrive at that idea?

What is "drawn into another dimension" supposed to mean?

And where did you get the idea from that space can be "drawn into black holes"?


What has the stuff above about mass and matter being drawn into black holes and then re-emerging to do with expansion??? And in what way is this "integral to the space"?

This sounds like as if you have fallen for a very common misunderstanding of the Big Bang theory: that the Big Bang happened at a single point, and everything flows away from that point. But the theory doesn't say that.


Sorry, I still don't understand what this is supposed to mean.


It also implies infinite volume (well, for the simplest possible topology). And obviously also that it never came from a point.

Essentially you are saying that a force and a velocity cancel each other (if I understand you correctly). That does not make sense.


What you described is (roughly) right for a spherically symmetric (around one single point), static spacetime. But the universe is not static and also not spherically symmetric (not around one single point - one could say it is spherically symmetric around every point), but dynamic, homogeneous and isotropic. Two quite different types of spacetime (although the first can be embedded in the second). Hence what you described simply does not apply to the universe as a whole.



But the effects of radiation have been "tied into" the BBT essentially right from the start (suggestion: before coming up with an "alternative idea", first look up if scientists haven't already thought of that decades ago!). What effects radiation has on the development of the universe is very well understood. And accelerating the expansion definitely isn't one of its properties - like mass, it slows down the expansion!


I beg to differ. By doing measurements and using some general properties, we can indeed figure out "what it does", without knowing what causes it. Knowing that would probably help in figuring that out and perhaps lead to new insights - but this knowledge is not required for finding out its basic effects.


In some systems, yes. But convection is by far not a universal process which would occur everywhere.

What does it mean to say that "energy cools down"?

What's this supposed to mean?

You could start making sense by presenting evidence that such a "condensing of mass" is possible.

Yes, but why should there be a cycle? What should cause the cycle to come into existence and remain stable?

Well, that's roughly what the Big Bang theory says: lightwaves expands because they travel through expanding space. Again, I suggest that you first look up what scientists actually say before coming up with "new" ideas.

Err, they don't. In fact, they appear to recede at velocites far greater than light. That's possible since we aren't talking about "real" velocities here, but about apparent velocities which are due to the expansion of space. Read e. g. this:
http://www.astro.ucla.edu/~wright/co...y_faq.html#FTL

Your explanation isn't that far from the usual Big Bang explanation. Again, I suggest you look it up. Try e. g. this:
http://www.astronomycafe.net/cosm/expan.html


(1) Calling this an "additional expansion" is quite strange wording. The term one should use is "accelerating expansion".

(2) This has not "recently" been shown to "compare" to the cosmological constant. It has been clear right from the start that a cosmological constant can explain these observations.

The expansion has been described as "space itself is expanding" already decades before the discovery of accelerated expansion. The observed acceleration has nothing to do with that.

I already pointed out that lensing has nothing to do with redshift.

Wrong. When space itself expands, it nevertheless has to "overcome" the "gravitational attraction" between the galaxies (for illustrative purposes, I'm using a mixture of Newtonian physics and GR here; describing this entirely in terms of GR is more confusing than enlightening).

There are lots of studies on active galactic nuclei (which are active because they contain active black holes). I just went to arxiv.org and searched for the term "active galactic nuclei" in the abstracts of the astrophysics section. Result: more than 1000 papers! ("active black hole" brought only 10 papers) However, these are scientific papers, submitted to very specialized journals, and hence not comprehensible to a layman with knowledge of only popular-level science.

I don't know about articles in the popular scientific press, sorry. But a quick Google search brought up these pages, which look quite interesting:
http://imagine.gsfc.nasa.gov/docs/sc..._galaxies.html
http://imagine.gsfc.nasa.gov/docs/sc..._galaxies.html
http://en.wikipedia.org/wiki/Active_galaxy

That would imply that everywhere where we have radiation of a lower temperature, mass should appear spontaneously, right? But physicists have already done quite a lot of experiments at lower temperatures (leading e. g. to Bose-Einstein-condensates). And the matter used in the experiments emitted radiation, AFAIK, which would have been then at temperatures lower than 2.7 K (if it was in thermal equilibrium with the matter - I don't know that for sure). No mass was ever observed to appear spontaneously in these experiments.

BTW, what about conservation of energy? Radiation of low temperature "consists" of photons of low energy. At 2.7 K, the energy of the photons is very probably even below the rest energy of the neutrinos, the lightest known particles. So what particles do you propose "condense" there?

I beg to differ. Most of modern physics works quite well without stories, and it was even only possible to come up with it when it was realized that not everything can be described with nice stories.


And you know this how, precisely?

I heavily recommend Feynman's book "The Character of Physical Law" to you. Especially chapter 2, about the relation between math and physics, and chapter 7, about the search for new laws of nature.

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The universe is big. Really big. It may seem like a long way to the corner chemist, but compared to the universe, that's peanuts. (Douglas Adams, Hitchhiker's Guide to the Galaxy)

No where do I claim Feynman or anyone else was unsatisfied with GR (or Newton). Feynman says simply that neither Newton nor anyone else since (that includes Einstein) has come up with the machinery, or mechanism,. In his full text, the world mechanism is used, also, as a synonym. There is no difference between mechanism and machinery, used as does Feynman.

Edited to add: This is exactly what I wrote: "The beauty of this interpretation is that it requires no new physics (no dark energy). It is entirely based on the original Einstein-de Sitter brainstorm of 1916-1918, both of which were static solutions to the field equations.

The apparent instability associated with either model is easily done away with when the physical mechanism of lambda and spacetime curvature (gravity) are understood."


One can read or interpret whatever one wants from those statements, but they say what they do, nothing more or less.

Coldcreation

I'm still thinking over that point. Suffice to say, a flat coordinate system and a relativistic coordinate system are not the same, but they can be used to make sense of one another. So, since redshift is based on the relationship of light to space, it represents a relativistic system. Could there still be a flat coordinate system in which galaxies are not actually flying apart at the speed of light?

The convection cycle is known physics. Inflation theory and dark energy are loose threads in a theory.

I don't follow how you don't understand cycles are inherently balanced? Think in terms of a gyroscope; What goes one way, comes back the other.

We have energy expanding out across the universe and mass contracting into gravitational cores. The matter breaks down into radiation, so does the radiation eventually complete the cycle?

Do we go into neurology?


It was tying two loose ends together. What happens to what is going into black holes and what is causing the dimension of space to expand. As I said, this was an early stage in my thinking, so hopefully it clarifies the evolution of my thinking, without further confusing the issue.

If space is being defined by the material in it and this material is being drawn into a black hole, then the space it defines is too.

As I said, it was an early stage in my thinking. Radiation does a far more logical job of carrying the constituent energy back out and evenly depositing it across the universe.

I know, it's an expansion of space, not an expansion in space. That's why I got onto this topic. If space is expanding, then how is it that we have a stable metric in the speed of light against which to measure it? If the speed of light doesn't increase as space expands, then there is another, otherwise stable dimension of space which the speed of light is measuring.
In fact, the Doppler effect isn't due to expanding space, it's due to increasing distance in stable space. The train might be moving away, but the railroad tracks are not being stretched.
If the speed of light were to increase as space expanded, there would be no redshift.
So i'm of the opinion this expansion of space isn't entirely logical.

In otherwords, it's a fairly basic, insinctive deduction, with which the experts disagree!

Is that infinite volume, or infinite dimension, as in drawing a line around a sphere creates an endless line.

You cannot get out of the BBT paradigm. I'm saying the redshift is due to lensing effects, not actual recession.

No, I'm not. I'm saying the redshift is due to lensing effect. Therefore everything APPEARS to be moving directly away from ANY observer and the effect is compounded, so the further away it is, the greater the recessional speed of the source APPEARS to increase.

It was thought up decades ago and it was called tired light theory. The problem was that the light wasn't dispursed by any intervening factors. My thought is that since redshift is a function of the wave property of light, could it be that all the light crossing every point in space from every direction of every frequency is affecting other lightwaves, much as water waves pile up. That photons are affected, it would be as an after-effect and not affect their line of travel. Obviously is would only take a very small interference, given the distances involved, to have the necesasary consequence. Maybe this is a little too crude a model, but it is radiation doing the expanding, so it would make sense to use it explain how the dimension of space appears to expand, just as gravity is a property of mass and not just something affecting it.

And its basic effect is to redshift the light from distant sources?

Well, we have radiation expanding out from gravitational bodies and mass collapsing into them. How is heat carrying moisture up until it gets cool and dense enough to fall back as rain not a similar cycle?

Even BBT proposes that, with the CMBR having cooled from the initial event and mass having formed/condensed into galaxies.

Radiation having lost energy through redshift. BBT assumes this marks the approximate age of the universe, but what if it is lensing of some sort and the age of the universe is, at the very least, far older.

At the level this would apply, string theory is investigating. At what point do the strings forming photons become those forming electrons?

For the first, because nature likes symmetry and balance. For the second, since everything is part of this cycle, matter and energy, what would destablize it?

The funny thing is that lightspeed isn't increasing as space expands. A redshifted light spectrum says space is increasing, while a stable speed of light says it isn't. Logically the stable measure is the constant, so the other is distance.

Same problem. Expanding space, stable lightspeed. What determines the speed of light, if it isn't a stable metric of space?

I will. Tomorrow.

Yes, because an expansion in space would mean we are at the center of the universe. A lensing effect doesn't create the contradiction of "expanding space" and a stable lightspeed.

Then explain how the speed of light is measuring a dimension which doesn't increase. All expansion is based on is the redshift of light, so which of these two proerties of light is the most fundamental?

Think of gravity as negative curvature of space and expansion as positive curvature. Gravity creates wells in space, but the expansion is like hills between the galaxies, so that if you were to bulldoze the hills into the wells, it would leave flat space. The distinction is just this abstract median, because distinguishing between the two is like deciding which is hill and which is valley.

Especially one who has to get up in less then seven hours.

Manana.

Pure speculation on my part. Maybe CMBR is what is left over, after the process. Given the explanation for which BBT gives for this residual level of radiation, ie. Inflation theory, it seems some form of phase transition determining this level is, at the very least, worth considering.

There are areas to which logical reductionism doesn't resolve all details. As Stephen Wolfram pointed out, it would take a computer the size of the universe to compute the universe. Is reality ultimately top down order, or bottom up phenomenology? Are laws ultimately an advanced form of Plato's essences and only exist to the extent they are expressed? Everything tends to follow the same basic principles, yet order requires a subjective point of reference as basis and it creates an arc of ascending and descending structure, beginning to end, birth to death. Of course it may be both and the tension only comes into play as top and bottom are separated by increasing levels of complexity. Word salad, I know. I'll post some thoughts on time and space, if you wish to consider them.

Math is the map. Even the experts admit they don't know all the territory. The fact is that it, like all though processes, is inherently reductionistic. We simply cannot factor in every detail, because while our thinking process is linear and reductionistic, reality is not. We all chart the most effective course we can, but order is islands in a sea of chaos. There is no objective frame of reference.

Thanks. Although I'm going on vacation next month and my girlfriend already bought me a couple of books. The one I'll probably have the time to read is about the history of the Wahhabi branch of Islam.