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No dark matter?
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 (May 4, 2011 at 10:49 am)Wormhole199 Wrote: Physics wise keep your mouth shut. "This then is the entire content of the Theory of Special Relativity: the Laws of Physics are the same in any inertial frame, and, in particular, any measurement of the speed of light in any inertial frame will always give 3×10^8 meters per second." http://galileoandeinstein.physics.virgin...c_rel.html
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 RE: No dark matter?
May 4, 2011 at 11:22 pm
(This post was last modified: May 5, 2011 at 12:02 am by Wormhole199.)
(May 4, 2011 at 7:27 pm)theVOID Wrote: "This then is the entire content of the Theory of Special Relativity: the Laws of Physics are the same in any inertial frame, and, in particular, any measurement of the speed of light in any inertial frame will always give 3×10^8 meters per second." Not all frames are inertial. In non-inertial frames the measured speed of light is not 299792.458 km/sec. In General Relativity (different than Special Relativity) it becomes "local inertial frames". In the presence of gravity the speed of light can be measured in a non-local inertial frame to be any value less than or greater than 299792.458 km/sec. An observer in a strong gravitational field, near a black hole for example, measures the speed of light at your location at a zillion km/sec. (May 4, 2011 at 6:12 am)theVOID Wrote:(April 26, 2011 at 7:04 am)Wormhole199 Wrote: It is about the effect of gravity on frames of reference. 299792.458 km/sec is the measured speed of light in local inertial frames. So if you want to make a comparison with "299792.458 km/sec" then you have to make it in a "local inertial frame". You never even defined your frame of reference. You should have kept your mouth shut.
My favorite site: Speed of Light.
 RE: No dark matter?
May 5, 2011 at 4:01 am
(This post was last modified: May 5, 2011 at 4:02 am by lilphil1989.)
(May 4, 2011 at 11:22 pm)Wormhole199 Wrote: In General Relativity (different than Special Relativity) it becomes "local inertial frames". In the presence of gravity the speed of light can be measured in a non-local inertial frame to be any value less than or greater than 299792.458 km/sec. A non-local frame means a global frame, and a globally inertial frame cannot exist in a non-Minkowski spacetime. That is, there are no non-local inertial frames in general relativity. The statement would be true if you said "not locally inertial" but this has a very different meaning to "non-local inertial frame". Should have kept your mouth shut? (Sorry, couldn't resist  )Chuck asked you a question, would you care to answer it? I think the answer is quite important because you seem to be making a "heads I win, tails you lose" kind of argument: It seems that if it turns out that a string theory is a good description of nature you'll jump up and down shouting that the quran predicted it; whereas if it is discredited, you'll claim that you just misinterpreted or start denying that you ever made the claim.
Galileo was a man of science oppressed by the irrational and superstitious. Today, he is used by the irrational and superstitious who claim they are being oppressed by science - Mark Crislip
RE: No dark matter?
May 5, 2011 at 4:31 am
(This post was last modified: May 5, 2011 at 4:37 am by Wormhole199.)
My favorite site: Speed of Light.
Not true. A local frame is one that only valid at a point or in a small region centred on some point (with small defined with reference to the curvature tensor components).
Nothing to do with observers or events. Wikipedia Wrote:In theoretical physics, a local reference frame (local frame) refers to a coordinate system or frame of reference that is only expected to function over a small region or a restricted region of space or spacetime. And the converse is that non-local reference frames are valid for an unrestricted region of spacetime i.e. a global frame. Chuck asked you a question, would you care to answer it? I think the answer is quite important because you seem to be making a "heads I win, tails you lose" kind of argument: It seems that if it turns out that a string theory is a good description of nature you'll jump up and down shouting that the quran predicted it; whereas if it is discredited, you'll claim that you just misinterpreted or start denying that you ever made the claim.
Galileo was a man of science oppressed by the irrational and superstitious. Today, he is used by the irrational and superstitious who claim they are being oppressed by science - Mark Crislip
RE: No dark matter?
May 5, 2011 at 5:35 am
(This post was last modified: May 5, 2011 at 5:37 am by Wormhole199.)
In all versions of String Theory there are 10 dimensions: "Time" plus the usual three spatial dimensions x,y,z (4 dimensions, our observable universe) plus six extra spatial dimensions making a total of ten dimensions (1 time + 9 spatial = 10 dimensions). Other competing theories like M-Theory has one extra spatial dimension (making the total 11 dimensions), however this extra spatial dimension is for the description of strings themselves (whether a string is a one-dimensional object like a thread, or whether a string is a rolled up two-dimensional membrane like a tube).
If the strings have thickness (or variable thickness as in this video) then we need this 11th dimension in order to describe them (to describe the tube). However if the strings have no thickness (always unity) then there is no need for the 11th dimension. In any case, in all currently competing theories, this Dark Matter is strings vibrating in six extra spatial dimensions. In this video the strings with different colors are actually vibrating in different dimensions. They do not interact with each other except gravitationally. The two dimensional membrane that they are attached to in this video is the three dimensions that we are used to projected on 2D (for this presentation). Photons only travel on this 2D plane (again for this presentation), and this is why we cannot see them. We can only detect the strings gravitational shadow on the 2D plane. (May 4, 2011 at 10:33 am)theVOID Wrote:Quote:however this extra spatial dimension is for the description of strings themselves (whether a string is a one-dimensional object like a thread, or whether a string is a rolled up two-dimensional membrane like a tube). What a clown.
My favorite site: Speed of Light.
(May 5, 2011 at 5:35 am)Wormhole199 Wrote: If the strings have thickness (or variable thickness as in this video) then we need this 11th dimension in order to describe them (to describe the tube). However if the strings have no thickness (always unity) then there is no need for the 11th dimension. In any case, in all currently competing theories, this Dark Matter is strings vibrating in six extra spatial dimensions. Infinitesimal not unity. Unity means, literally, "of unit". So "thickness unity" depends entirely on whether you're using metres, inches, h=c=1 or whatever. You call out others' knowledge when you've demonstrated quite clearly that you don't have much of a grasp on the concepts you're trying to discuss. I think there is but one clown in this thread. Spoiler: Chuck asked you a question, and I've asked you twice now to address it. If you want a discussion, then take part in it. If you're not interested in discussion and just want to keep spamming the same crap whilst ignoring everyone's replies, go right ahead, but don't be surprised when you get banned.
Galileo was a man of science oppressed by the irrational and superstitious. Today, he is used by the irrational and superstitious who claim they are being oppressed by science - Mark Crislip
** MOD NOTICE ***
Wormhole and alemcodon .. cut out the links to your prosthelytizing sites. As this is in the science and not religious section, address the points succinctly with references. Your refusal to address direct questions while continuing to preach is not in line with our forum rules. If you can't do this you'll have to earn your way back through the gauntlet [/mod hat]
"There ought to be a term that would designate those who actually follow the teachings of Jesus, since the word 'Christian' has been largely divorced from those teachings, and so polluted by fundamentalists that it has come to connote their polar opposite: intolerance, vindictive hatred, and bigotry." -- Philip Stater, Huffington Post
always working on cleaning my windows- me regarding Johari  RE: No dark matter?
May 8, 2011 at 5:16 pm
(This post was last modified: May 8, 2011 at 5:20 pm by little_monkey.)
(May 5, 2011 at 4:31 am)Wormhole199 Wrote: Sorry for being late on this thread. However, that is totally wrong. The speed of light near a black hole, or anywhere else, is the same. Deny that, and you're denying the foundation of Special and General Relativity. Inside the black hole, the light doesn't escape because it is bent by gravity into a circle, and so doesn't escape, but its speed remains the same. Outside the BH, your clock will slow down and your ruler will shrink, nevertheless, you will end up measuring the speed of light to be c. RE: No dark matter?
May 8, 2011 at 11:48 pm
(This post was last modified: May 8, 2011 at 11:50 pm by Wormhole199.)
(May 8, 2011 at 5:16 pm)little_monkey Wrote:(May 5, 2011 at 4:31 am)Wormhole199 Wrote: Suppose that you are outside gravitational fields, and that you have a clock and a ruler (which is not rotating with respect to stars), and that you are not accelerating. Based on your clock and ruler what is the measured speed of light near a black hole?
My favorite site: Speed of Light.
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