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Author | Topic: what is the big bang and how do i understand it? | |||||||||||||||||||||||||||||||||||||||
JustinC Member (Idle past 4872 days) Posts: 624 From: Pittsburgh, PA, USA Joined: |
quote:Yep, I almost convinced myself that I understood it also. Then I read pmb's posts at the SciForum: Relativistic Mass vs. Rest Mass | Sciforums He seems to be saying that the strength of a gravitational field is dependent on one's reference frame, since mass increases with speed. Consequently I've been reading alot about mass, and there seems to be some dispute about whether one should use relativistic or proper mass when explaining GR and SR. Is this true? How is it false to conclude that mass has increased since it seems to have more inertia the faster it goes? Even if one uses the energy-momentum equation: E^2 - p^2=mo^2 It still seems that as you rotate in spacetime, you will increase the E and p. And since p=mv, m would eventually have to increase.
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cavediver Member (Idle past 3671 days) Posts: 4129 From: UK Joined: |
Well, if you will read the statements of cranks, you're going to get confused.... and no, I don't mean my comments!
If you look at non-invariant quantities (i.e. non-scalars) you will get non-invariant observations. If you look at scalar quantities, they will not change. The Ricci scalar curvature CANNOT change just by changing your frame of reference. End of story. Looking through his posts, he is very confused about a great many things (for instance, what it takes to get a black hole). I'd stick to this board to learn anything
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cavediver Member (Idle past 3671 days) Posts: 4129 From: UK Joined: |
E^2 - p^2=mo^2 It still seems that as you rotate in spacetime, you will increase the E and p. And since p=mv, m would eventually have to increase. Well, E and p do increase as they are not scalars but you have Mo remaining invariant as it is a scalar. p=mv is not a relativistically sensible expression. neither p, m, nor v are scalars here.
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JustinC Member (Idle past 4872 days) Posts: 624 From: Pittsburgh, PA, USA Joined: |
How does one become a crank? There seem to be so many of them boobytrapping my education. I guess I'll read up on Ricci curvature, though I'm sure you are correct.
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Son Goku Inactive Member
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cavediver has covered most points, so I'll only be adding a bit.
quote: It isn't an adjustment because it was in the theory from its creation.
quote:Something, some relationship, it doesn't make a difference. A physical process couples to lambda, be it a relationship or a thing. Dark energy was a guess and the Casimir experiments make it the most likely candidate so far. quote:I don't understand what is wrong with this.quote:and you get upset when I think that this branch of physics is getting more concerned with working out the mathematics of the theory than with explaining the physical universe? Given a configuration of matter, General Relativity will give you the geometry it produces and this geometry is gravity. What exactly do you mean by "more concerned with working out the mathematics than explaining the physical universe"? The maths has to be solved to explain the universe. To give you an example I've seen first hand, it took a parrellel network of super-computers several days to solve Einstein's equation for two binary neutron stars. The information on this arangement of mass was fed in and using Einstein's Field equation read outs of the resultant gravity was obtained. Information from the "PSR J0737-3039" system and several others since match the outputs of these calculations so exactly you'd need a microscope to see the margin of experimental error. quote: That would be General Relativity.
quote:The unobserved matter isn't added to General Relativity to fix or make it match observational evidence. General Relativity matches observational evidence. The question is: "Why do I need all of General Relativity for cosmological distances?" quote:Nobody has ever added extra dimensions to account for unexplained observations. quote:That would leave a horrible mess of scalar equations which would be unusable. quote:Considering that Einstein's theory is a theory of spacetime that would be a difficult view to keep in General Relativity.
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JustinC Member (Idle past 4872 days) Posts: 624 From: Pittsburgh, PA, USA Joined: |
quote:Would the relativistically sensible expression be: p=(lambda)[(mo)(v)] and some people interpret (lambda)(mo) to be a mass increase, when it could just as easily be interpreted as an adjustment factor of momentum in whole? Can all experiments which are interpreted in terms of mass increase be interpreted in terms of momentum increases?
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RAZD Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Let's try taking a different tack.
Would you agree that
Physical Evidence for Dark Energy (click - pdf of whole article)We present here measurements of the cross-correlation function between the currently available SDSS galaxy data and the WMAP CMB maps of the sky. ... Assuming a flat universe, our preliminary detection of the ISW effect provides independent physical evidence for the existence of dark energy. Is the current level of evidence for the existence of dark energy based on the standard model (BB, inflation, GR, SR yada yada)? Good. Would you agree that
Illuminating the Dark Universe (click - Science Mag online, sign in required) Portraits of the earliest universe and the lacy pattern of galaxies in today's sky confirm that the universe is made up largely of mysterious dark energy and dark matter. They also give the universe a firm age and a precise speed of expansion. In February, the Wilkinson Microwave Anisotropy Probe (WMAP) produced an image of the infant cosmos, of all of creation when it was less than 400,000 years old. Five years ago, Science's cover sported the visage of Albert Einstein looking shocked by 1998's Breakthrough of the Year: the accelerating universe. Two teams of astronomers had seen the faint imprint of a ghostly force in the death rattles of dying stars. Lingering doubts about the existence of dark energy and the composition of the universe dissolved when the WMAP satellite took the most detailed picture ever of the cosmic microwave background (CMB). ... tiny fluctuations in the temperature ... reveals what the universe is made of. The answer was disturbing and comforting at the same time. The WMAP data confirmed the incredibly strange picture of the universe that other observations had been painting. The universe is only 4% ordinary matter, the stuff of stars and trees and people. Twenty-three percent is exotic matter: dark mass that astrophysicists believe is made up of an as-yet-undetected particle. And the remainder, 73%, is dark energy. Means that the universe is:04% ordinary matter 23% dark matter 73% dark energy Yes? Good. Would you agree that We have no idea of the (who\what\where\when\why\how} of dark matter or dark energy ... that this {issue} is still ... dark? Good. Because this leads me to the inevitable conclusion that either: (A) The universe is composed of ordinary matter, the stuff of stars, planets, cosmic dust, asteroids, animals, trees and people -- and the theory is {wrong\incomplete}, OR (B) The universe is 96% +/- 96% (refigure all %s accordingly)(*) unknown in composition, behavior, derived theories, etcetera (there can be no theories about the existence\behavior of things we do not know about) -- and the theory is irrelevant as it only deal with the behavior of 4% of the total, OR (C) There is some other answer. (*) -- this is to signify that if we don't know jack about the dark stuffs they could behave entirely different than our expectations, the "rules" governing them being different as well. Enjoy. ps -- I trust you also agree that these sources are not hyperbolic media reports misrepresenting science for sensationalism ... we are limited in our ability to understand by our ability to understand RebelAAmerican.Zen[Deist
... to learn ... to think ... to live ... to laugh ... to share.
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RAZD Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
see Message 97
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cavediver Member (Idle past 3671 days) Posts: 4129 From: UK Joined: |
Nice and concise... I only hope you did actually read my previous posts
It's bed time (as in several hours past), but I think I'll make a quick reply:
Means that the universe is: 04% ordinary matter 23% dark matter 73% dark energy Yes? No, not really.
ps -- I trust you also agree that these sources are not hyperbolic media reports misrepresenting science for sensationalism ... Well, ok, but they're not reporting the facts very well. This is a case in point:
quote: What does this mean? By mass, by weight, by flavour, by sponginess, or by contribution to density? It is very misleading, and is really the root of your troubles. It is very silly comparing the dark energy composition to the matter composition... they are such different concepts. The real mystery is still the 1:6 luminous_matterark_matter ratio. But there is no reason that the dark matter is anything more than normal gravitating matter (from hypothetical axions to neutrinos to machos). And as I've said repeatedly, the dark energy contribution is part of GR... it is to be expected. It is also predicted by supergravity and superstring theory. These sources you quote are reasonably accurate but still layman's guides... believe me, as a one-time expert at probably the world-centre for such stuff. When they talk about dark energy being unknown, they are not giving the correct view. I know what they mean, but it is not what you are taking it to mean, not that that is your fault. My question was always "why is it [dark energy] zero [absent]?". Now we know it's not. I can assure you, once the acceleration was verified, many of us were going "I knew it had to be there". Just because we didn't mention the cosmological constant when we described BB theory to people doesn't mean we didn't know about it.
Would you agree that we have no idea of the (who\what\where\when\why\how} of dark matter Not "no idea" at all, we have plenty of ideas. We just need more observational (astronomical, cosmological and particle) evidence to narrow down the possibilities.
or dark energy We have one primary candidate which has been about for 90 years! This is what I keep saying. Just because the sources you are reading give the impression that we're in the dark, it doesn't make it true.
(A) The universe is composed of ordinary matter, the stuff of stars, planets, cosmic dust, asteroids, animals, trees and people -- and the theory is {wrong\incomplete}, Possible
(B) The universe is 96% +/- 96% (refigure all %s accordingly)(*) unknown in composition, behavior, derived theories, etcetera (there can be no theories about the existence\behavior of things we do not know about) No. Most if not all of the possibilities for this "96%" are known with known or predicted behaviour.
-- and the theory is irrelevant as it only deal with the behavior of 4% of the total, Absolutely no. The theory of GR deals with all 100%. The 4% is the luminous matter. GR could not care less whether stress-energy is in the form of luminous matter, dark matter, dark energy, any other form of energy. It deals with it all very comfortably.
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RAZD Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
What does this mean? By mass, by weight, by flavour, by sponginess, or by contribution to density? Well, for starters I would assume we are talking about matter and energy and More later
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cavediver Member (Idle past 3671 days) Posts: 4129 From: UK Joined: |
I saw that you had made a super quick reply, and I was going congratulate you... and then I saw this measly offering...
More later Couldn't be any less
Well, for starters I would assume we are talking about matter and energy and E=mc2conversion of energy to mass. Unfortunately not that simple... especially as "dark energy" appears as an effective -ve energy! Tends to screw up simple %'s. As I said, this comparison is very naive.
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RAZD Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
"dark energy" appears as an effective -ve energy! oh that helps ! ... but isn't gravity supposed to be negative energy, so that you get(which would of course make % impossible to calculate) Perhaps they used sum{|each item in universe|} as the base. {wanders off muttering ... } we are limited in our ability to understand by our ability to understand RebelAAmerican.Zen[Deist
... to learn ... to think ... to live ... to laugh ... to share.
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RAZD Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
The real mystery is still the 1:6 (luminous_matter/dark_matter) ratio. But there is no reason that the dark matter is anything more than normal gravitating matter (from hypothetical axions to neutrinos to machos). Except that (as you say) there has to be 6 times as much of {it} as everything else we have ever been able to observe, measure, postulate or tweak out of the depths. That's a lot of quarks in the system! And that is still a quarter of the {total stuff} (by whatever metric they used).
And as I've said repeatedly, the dark energy contribution is part of GR... it is to be expected. It is also predicted by supergravity and superstring theory. ... Not "no idea" at all, we have plenty of ideas. We just need more observational (astronomical, cosmological and particle) evidence to narrow down the possibilities. So ... no solid enough ideas to bet a "would it" nickel on eh? Expected when you make lamda (cosmological, non-zero vacuum energy, whatever) non-zero except that it is zero for all normal space -- that part?
Possible Good
No. Most if not all of the possibilities for this "96%" are known ... Sorry, but didn't you just say that you have tons of ideas, but not any {evidence\observation\test} to narrow the field ... or tell you if you are even in the right ballpark?
Absolutely no. The theory of GR deals with all 100%. But you still only have validated, hard observation\data of the {normal matter\energy} and not any for the dark stuffs ... How can you say that GR deals with stuff when you don't know what the stuff is? All you have are postulates about what the stuff would be like if it were around and operated according to GR, when in {possibility} it could be something entirely different, which is also why we are having so much trouble finding it. Enjoy.
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Ingvar Inactive Member |
RAZD wrote:
quote: "The accelerating universe" is a misinterpretation of measurings of the galaxies' radiation where Edwin Hubble found that the spectral lines are redshifted. The right explanation is that the radiation's waves are fractionally dissipating by elongation, which implies accelerated displacement of the radiation’s wave-spectrum. This phenomenon was not understood but interpreted as a Doppler-velocity caused by the galaxies recession -- so Hubble multiplied the redshift-rate with the light-speed (c) and fond (1929) that all galaxies seem to move away at 500 km/s/Mpc. Max Planck also analyzed measurements from (heat) radiation and he found that there was a constant change with the increasing wavelengths. Planck interpreted it as changes of energy measured as temperature, but didn't understand his interpretation. (See his Nobel speech at Management trainee till Nobelstiftelsen - NobelPrize.org) The answer is that both Hubble and Planck have measured the same phenomenon but made different and wrong interpretations. It is not the universe that is expanding or accelerating, but it is the radiation's wave-spectrum that is accelerating by elongation. Planck analyzed measurings of heat-radiation’s wavelengths-units, but transformed it to frequency-units to compare the temperature as energy per time-unit (effect). But it isn't the heat-radiation's energy (temperature) that is quantified, it is the radiation’s wave-units that are constantly displaced by the fractional rate of 6.6 x 10^-34. Wien's displacement law demonstrates that wavelength and temperature are proportional to each other. So, Hubble found but didn't understand that the radiation is displaced by the same rate that Planck found but neither understood. It implies that the galaxies' radiation is redshifted 1 Angstrom per 16 million light-year. Astronomers have reduced this number by an asymptotic equation to not exceed 100% of the light-spectrum's redshift, which should imply velocities faster than c. RAZD wrote:
quote:Dark matter is an interpretation of the misunderstood distribution of the velocity of the stars in the rotating spiral galaxies. Measurements show that all stars have the same velocity. This has been interpreted as if the galaxies rotate as a stiff plate which should be impossible according to Kepler's laws. Their orbital velocities must decrease with their increasing distance. So dark matter was invented as a help-hypothesis to explains this anomaly. But the right explanation is that they (Zwicky and Rubin et. al.) have mixed up angular velocity with orbital velocity. But the Doppler-measurings reveal the same orbital velocity of all stars in a galaxy-arm, which means that their angular velocities decreases proportionally with increasing distance and in balance with the decreasing gravitation from the galaxy-center. Which is in harmony with Kepler’s laws. So there is no need for dark matter to explain the rotating galaxies' just apparent velocity-anomaly. There is nether need for dark energy to explain the accelerating redshift. Ingvar Astrand, SwedenThe Unified Theory of Physics
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RAZD Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
welcome to the fray.
I'll let the big guns demolish your position, which has already been refuted before on this forum. (peachharris and "tired light") seeEvC Forum: Falsifying a young Universe. (re: Supernova 1987A) you may need to read through a lot of side comments to get to the issue of distance versus speed of light versus red-shift. Enjoy. This message has been edited by RAZD, 09*21*2005 08:24 AM by our ability to understand RebelAAmerican.Zen[Deist
... to learn ... to think ... to live ... to laugh ... to share.
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