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The expansion of the universe is a manifestation of the principle of Conservation of Energy.
Thread Index of Key Points Introduction (below) The Actual Expansion Rate #7 Cosmic "Sea-level" #15 Dealing With Infinity #24 The Basic Picture #27 The Crux of the Matter #55, p2 The Big Picture #56 Einstein's Sublest Error #57 Contraction Energy Estimate #33 p3 Expansion Energy Est. (revised) #256 p 9 On-going Discussion page 3 + Figure 1 & Figure 2[Print these two figures to follow along in the text. The original urls no longer work , and the printed versions are easier to understand anyway]Everywhere in the universe, matter is "falling together," radiating energy "into space" as it does so. What happens to all this energy radiated "into space"? It causes "space" to expand! General Relativity allows for this. In GR, space can bend and stretch, and it does so in such a way that the total energy content of the universe is constant. Space expands in GR as naturally as water flows downhill. Except for the trivial case of a cold, collapsed body, all gravitational systems either expand or contract. Contraction always tends to occur near "centers of mass," and expansion tends to occur away from the center. The sun's core is contracting, but its outer envelope expanding. Satellites near to earth spiral in; those beyond the geosynchronus orbit spiral away. The cores of globular clusters contract; their outer halos expand or get torn apart by tidal forces. The core of a supernova collapses, the outer parts blown away. Since all gravitational systems are unstable, either contracting or expanding, and since all contraction tends to take place "locally," it logically follows that on the largest scales, the residual effect must be expansion. The universe is in almost perfect balance...but not quite. Locally, the net effect is contraction, accompanied by the release of energy. Cosmically, the net effect is expansion. The expansion of the universe, acceleration and all, is due to "balancing the books" on energy. Last edited by Peter Wilson : 06-November-2006 at 06:19 PM. |
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An example will help clarify.
The earth-moon system, like the universe, is expanding. Both are expanding at about the same rate: the universe at about 72 parts-per-trillion-per-year (ppt/yr) and the moon's orbit at about 100 ppt/yr. (1 km/sec/mpc = 1 ppt/yr) Both are "almost perfectly" balanced (not "perfectly"!), but not quite. The expansion rate of the cosmos and the earth-moon system are both "almost zero." Neither is in "perfect" balance, but both are very close. Is "dark energy" causing the moon's orbit to expand? No, it is rotational energy of the earth. The earth's rotational energy is being transformed into gravitational energy of an expanding earth-moon system. Is dark energy causing the universe to expand? No, it is "light energy." More specifically, radiation eneregy in all forms (radio waves to gamma rays; neutrinos; gravitational waves; & cosmic rays). Visible matter radiates energy, which is why it is visible, and this energy drives the expansion, according to the principle of Conservation of Energy. In other words, Dark Energy is light energy! |
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Isn't that a poor example ? Astrophysicists agree that that the Moon will eventually achieve escape velocity, and be hurled off somewhere else in the solar system.
But the dark matter / dark energy discussion has typically revolved around the unexplained high velocity of galaxies and galactic clusters. Gravity is actually a very weak force in atomic terms. It takes significantly large bodies to see and measure these effects. |
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Likewise, the high velocity of remote galaxies is easily explained: it is just gargantuan volumes of space expanding expanding at an infinitesimal rate. The velocity is high when you go to billions of light-years distance (just as 4% APR comes out to a lot when the debt is in the trillions of dollars), but the rate of expansion is infinitesimal. The rate of expansion is so small, 0.000000000073/yr, that the energy involved is also very small. And the energy emitted by visible matter easily explains energy involved in the infinitesimal expansion. When astronomers report on distant galaxies, they come up with a lot of "gee-whiz" numbers. Don't let the numbers fool you: the rate of expansion is infinitesimal, and so is the rate of energy gain, and so it is easily explained. |
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Have you worked on this idea, Peter Wilson, to the point where you have some equations, numbers, maths and stuff to describe it?
If you haven't, do you expect that you will, sometime in the next three months (say)? If you don't, perhaps you'd be kind enough to let us know how you think BAUT members could attack your idea, with glee and fervour (per the BAUT rules, ATM section)? For example, what - in principle - could anyone present that could show your non-quantitative description is inconsistent (internally, with GR or QFT, with good observational or experimental results)? |
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I have worked on this for so long and from so many angles, the problem is what to leave in, and what to leave out. So rather than trying to explain everything at once, in this forum I have laid out the basic premise, and will respond to attacks/questions/criticisms as they arise.Numbers are hard to come by, because astrophysicists are using a different paradigm. I know that sounds like a lame excuse, but I have asked many a PhD professor for the numbers, and they mostly ignore the question; the kinder ones tell me, “Sorry, you’re wrong.” I do not know how a question can be “wrong,” but that is the response I get when I ask for the numbers! So let me start with the “easy” one, the Hubble constant. Suppose you ask your broker, “What is the bond rate today?” Your broker replies, “Its at 72 Lira per second per ton of gold.” What would you do with this information? It is utterly useless, because the units are so arcane. So it is with the Hubble expansion, expressed in kilometers per second per megaparsec (km/sec/mpc). These units are misleading, to say the least. They make it sound like the universe is coming apart at the seams! But it is not; the rate of expansion is sub-sub-sub-microscopic. To convert into meaningful units, we must first divide by the number of kilometers per megaparsec, to get rid of the confusing distance-per-distance. Using the “accepted” value of Hubble constant, 72 km/sec/mpc: (72 km/sec/mpc) * 1 mpc/(3.09 x 10^19 km/mpc) = 2.3 x 10^-18/sec. This number is so small, out of mercy, we multiply it by the number of seconds in a year, to get the expansion on an annual rate, like interest on a bond: (2.3 x 10^-18/sec) * (3.15 x 10^7 sec/yr) = 7.3 x 10^-11/yr = 73 ppt/yr Since the place-value for the number of kilometers-per-megaparsec (3.09) and the number of seconds-per-year (3.15) are almost the same, and their exponents differ by 12 (a factor of one trillion), it is handy to “round-down” the conversion factor to: 1 km/sec/mpc = 1 ppt/yr. In ordinary, scientific terms, the universe is expanding at a rate of about 72 ppt/yr, or 73 ppt/yr if you insist on accuracy. This is a small number. Very small. But I didn’t just pull it out of a hat. Is it clear now where this number comes from? And is it clear that the universe is expanding at a very, very small rate? Last edited by Peter Wilson : 16-May-2006 at 08:47 PM. |
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To what extent, if any, does your idea incorporate the physics which astronomers and cosmologists use in their work?
Specifically, QED (which incorporates a quantum theory of 'light', and includes 'energy'), and GR (which differs immeasurably from Newtonian theory in most regimes). Also, I didn't see where you answered this question of mine: Quote:
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Last edited by Peter Wilson : 10-March-2006 at 04:15 PM. Reason: Add title |
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In Newtonian gravity, this creates a paradox: where does the energy "radiated into space" go? General Relativity resolves this paradox by allowing space itself to expand. While the difference between Newtonian and GR is "immeasurable," do not forget that the expansion itself is infinitesimal. As for how anyone could show that my non-quantitative description is inconsistent...I have no idea. GR and CE (conservation of energy) are consistent, as far as I know. The universe we see, radiating energy at the rate we observe, will expand at a residual rate, according to GR. The only question, as you suggest, is this one: What is the rate? At what rate does GR say our universe should expand? That is the $100,000 question. Last edited by Peter Wilson : 10-March-2006 at 04:17 PM. |
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Thanks for the clarifications Peter Wilson.
Earlier in this thread you said: Quote:
Perhaps a first step to testing your idea would be to find out how much 'light energy' there is, throughout the universe? Let's start with our solar system. An utterly trivial fraction of the solar system is occupied by stuff that's opaque to (most) electromagnetic frequencies - TeV (and higher energy) gammas from AGNs are detected smashing up (Earth's) atmosphere molecules, COMPTON detected lots of gammas of lesser energies (from even further away), XMM-Newton regularly produces lovely pictures of distant galaxies, ... and so on. There are, of course, some obstacles - Jupiter, the Sun, and the IPM below the plasma frequency, but 'light' finds our solar system essentially empty. So we can add up all the photons, of all the frequencies, that come from all over the sky, to see how much 'light energy' there is. Right? What would such an investigation conclude? (An OOM - order of magnitude - answer would be just fine). |
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Below about 5 Mpc—I am not sure of the exact distance—the Hubble relation “doesn’t work,” due to local motions. Case in point, the Andromeda galaxy (M31) is about 1 Mpc away, and would be receding at 72 km/sec per the Hubble expansion, but instead is coming at us at 100 km/sec (and gaining!) Contraction and expansion in the cosmos are complementary, in the same way that erosion and sedimentation are complementary in geology. Every square foot of the earth’s surface is generally either in the process of being eroded-away or “sedimented”-in. On the surface, the two processes mix and match endlessly. Yet below sea-level, there is net sedimentation, and above sea-level, there is net erosion. Likewise, in the cosmic dance, expansion and contraction intermingle endlessly. I already mentioned the space between the earth and moon is expanding at 100 ppt/yr. On the other hand, the space between earth and man-made satellites contracts (they spiral back down). The height of geosynchronous orbit (GESO), about 24,000 miles above the equator, is the dividing line or “inflection point” between expansion and contraction. Below GESO, satellites spiral in, above it, they spiral away. Right at GESO, they are at a quasi-static orbit, but eventually—without adjustment—a satellite at GESO will drift into one bin or the other: expansion or contraction. All astronomical systems are rife with such inflection points, of all character, where things either fall in or fall away. As with the “sea-level” on earth that provides the dividing line between net-erosion and net-expansion, this 5 Mpc dimension, while not as clear-cut as the shoreline, nonetheless provides a conceptual divide: within a 5 Mpc “volume” there is net-contraction; beyond it, there is net expansion. So this 5 Mpc distance represents the “minimum” below which, as you asked, the Hubble relation does not apply. Last edited by Peter Wilson : 10-March-2006 at 04:23 PM. |
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1 mpc/(3.09 x 10^19 km/mpc)
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I think I understand your effort: to simply. But multiplying by 1/x/y is not the same as dividing by 1/y/x. I do like your train of thought but the switch to ppt still baffles me. Give me some time to re-think your proposal- 12 hours.
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Fred Cooperstock and Steven Tieu (C&T) have submitted calculations for journal publication that show galactic “dark matter” is explained simply by properly applying GR to galaxy rotation. http://www.space.com/scienceastronom...rk_matter.html Their calculations have met with a lot of skepticism, but as Einstein would say, “The theory is correct,” and their work will surely be accepted. It will certainly go down in history as a turning-point in our understanding of the cosmos. “Dark matter” has been an enigma for about 7 decades. Ironically, GR has been around for about 8. Why did no one previously turn to GR as an explanation for dark matter? As far as I know, Einstein was as baffled as anyone by the mystery of dark matter, and he would surely be pleased to know that yet another long-standing observational mystery is explained by his venerable theory. In the narrow, conservative manner of academics, C&T only claim to explain dark matter within spiral galaxies, but I am betting that when the dust settles, GR will explain intergalactic dark matter as well. And of course, I’m betting that when the dust settles, GR will explain “dark energy,” in a round-about sort of way. Take the observed distribution of visible matter in the universe, and the rate at which it is radiating energy; model the observed distribution of matter and the energy radiation using GR, and you will find that “space” expands at some rate in such a model. My central contention is that when this calculation is done, the predicted rate of expansion will be close to or equal the observed rate of expansion, 73 ppt/yr. |