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I thought it already started -- on the first Wednesday in November. The Democrats won't take control officially until January. Don't count them out yet! Both parties are such excellent cooks when it comes tossing up a meal of red herring with some tripe on the side. Regarding immigration reform, I see that as a populist movement more than an issue either party can claim as its own. Whether it continues to pick up momentum or withers away depends on how the economy performs. To tell the truth, I suspect the leadership of both parties would rather not be bothered with immigration reform.

A pseudoscientist is quick to write an internet blog on his "theories", complete with twirly, animated GIFs and multiple copyright statements. A pseudoscientist is quick to post his "theories" on not-quite-professional web sites such as SFN (we have some professionals here, but they discuss the serious stuff elsewhere). A pseudoscientist does not post his "theories" on web sites where multiple professionals who could rip those "theories" to shreds hang out. Jeesh. Edit here: A pseudoscientist is might be well-versed in HTML and Word but does not know how to use LaTeX.

The ball is subject to length contraction. Big deal. We can shrink its diameter down to the Planck length with a high enough relativistic velocity. The ball still has some location as perceived by the crew. This location is some fixed point on the ball. A point is not subject to length contraction. It remains a dimensionless point regardless of the observer's velocity relative to the point. The speed of light is the same to all observers. How can some object (e.g., the ball) be observed to exceed the speed of light by the crew? It cannot (unless you reject special relativity also). One can get a superuminal velocity by mixing frames. Case in point: Sure. The crew can traverse multiple light years (as measured in the galaxy frame) per picosecond (as measured by the crew). Do you see the mixing of frames going on here? If you want to measure the velocity of some object as perceived by an observer in some frame, the distances must be measured with rulers fixed in the observer's frame and times must be measured with clocks fixed in the observer's frame. You are not doing this. In other words, you want to measure the ball's crew-frame velocity using a ruler in star frame. I'm sorry for the poor wording here. Obviously the ball is moving in the crew frame. What I meant was that this vector is expressed in the crew frame. I used fixed here meaning not subject to length contraction. Correcting that poor choice of words, It had better be expressed in the crew frame or the resultant velocity will be invalid. No, I just choose my words poorly. Right back at ya, you are a pedant and a crackpot.

All it takes is a little thought to see that this cannot be the case and remain consistent with special relativity (with which zanket claims to agree). If the ball can traverse the rocket in an arbitrarily short interval of time in the frame of the crew, the ball can exceed the speed of light in the frame of the crew. Something is obviously wrong here! Most reasonable people would think, "Oops, I screwed up somewhere. Now where did I make my mistake?" Crackpots do not think that way. They cannot be make mistaken. They charge forward, piling one mistake on top of another. They use non sequitur, rhetoric, false analogy, and argue till you are blue in the face. They refuse to admit errors, just like happened over at the website to which you referred in post 54 (this one: http://forum.physorg.com/index.php?showtopic=9591&st=122). Just because zanket pulled the wool over the eyes at some other website does not mean zanket is right. Here is another website to which zanket posted his garbage: http://www.sciforums.com/showthread.php?t=58421. What happened there is a different story. One of the users knows general relativity. There has been no reply from zanket after his "theory" was shown to be rubbish. Typical crackpot reaction. No apology; no response at all. Untangling the web of errors in a crackpot theory is a chore and leads to little of any use. This is why a lot of reasonable people on this website don't bother addressing crackpot theories. This is why dead-serious physics websites (those that attract a lot more physics professionals than does SFN) simply ban the crackpots.

My bad. There are not enough nines here to make the galaxy 1 millimeter in diameter. I want [math]\gamma=\frac 1{\sqrt{1-(v/c)^2}} = \frac{10^5\ \text{ly}}{10^-3\ \text{m}} = 10^8 \frac{\text{ly}}{\text{w}} \approx 10^{24}\text{\ using\ } 1\ \text{ly} \approx 10^{16}\ \text{m}[/math] The correct velocity is v = 99.99999999999999999999999999999999999999999999995% c.

A quick question: Let the height of the rocket be [math]h[/math]. Suppose the ball can traverse the rocket in an arbitrarily small amount of time in the frame of the crew. In particular, suppose the crew observes the ball to traverse the rocket in time [math]0.1 h/c[/math]. What is the velocity of the ball in the frame of the crew? Edited to add I looked at your diagram. You are indeed mixing frames. This time, you be the one to keep an open mind. CXXXXXB is fixed in the frame of the crew and is not subject to length contraction. You even used braces to show that this is in the frame of the crew. XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXS is in the frame of the star S and is subject to length contraction. It is the length contraction that makes the crew able to traverse the length of the galaxy in an arbitrarily short period of time. The CXXXXXB length is not contracted. Suppose our spacecraft is 10 meters long and that we are moving at 99.99999999999999999999999999999999995% the speed of light relative to some galaxy that is about 10⁵ light years in diameter. Our velocity shrinks that galaxy down to an apparent diameter of 1 millimeter. It does not take long at all (about 3.34 picoseconds) for a particular point on the spacecraft to traverse the length of that apparently miniscule galaxy. It takes a bit longer (33.4 nanoseconds) between the time the nose of the spacecraft passes over the first arm of the galaxy and the tail passes over the last arm. The spacecraft is still 10 meters long. Add a whole bunch more 9s and our spacecraft can traverse tip-to-tail an entire galactic supercluster in 33.4 nanoseconds. Add a whole bunch more 9s and we can make that 33.4 nanoseconds to traverse the known universe, tip-to-tail. But it still takes 33.4 nanoseconds for the rocket to pass tip-to-tail over any one particular star in the known universe. Or, for that matter, 33.4 nanoseconds to pass tip-to-tail over a ball tossed into the air on a planet orbiting that one particular star. Mods, please put this thread in Speculations.

You would not be pulled back toward the ring. It is a fictitious force, after all. However, when you jump, you retain the tangential velocity you had prior to your jump. End effect: You collide with the wall. In short, you could simulate gravity by making a big ring and spinning it. Your inner ear might not like it. (It is a fictitious force, after all.) The effects on your inner ear can be reduced by making a big ring.

So what? The rocket traverses the galaxy in an arbitrary period of time because the galaxy shrinks due to length contraction. The rocket itself does not shrink in the frame of the crew. You are mixing frames, a very bad thing to do, particularly when dealing with relativistic effects. The ball cannot move faster than the speed of light as seen by the crew. In particular, the point at center of the ball, as seen by the crew, cannot traverse the length of the rocket in time [math]h/c[/math] or less. The black hole at the center of the galaxy (or any other point) is subject to the same constraint. This is the misapplication of the equivalence principle that gets you into trouble. From http://relativity.livingreviews.org/Articles/lrr-2001-4/: The outcome of any local non-gravitational experiment is independent of where and when in the universe it is performed. You are not performing a non-gravitational experiment here. You are asking how a point mass accelerates a body with negligible mass. You misapplied those equations. The second postulate (the speed of light is the same to all observers) is very applicable. Think about what you are saying in your paper in light of this postulate. By saying the ball can traverse the spacecraft in an arbitrarily small amount of time, you are saying the ball can exceed the speed of light.

Wrong. A sufficient velocity relative to the galaxy makes the galaxy shrink to the size of a pinhead in the crew's frame. The rocket has zero velocity in the crew's frame. I do not equate those anywhere in the paper.I do not equate those anywhere in the paper. Quote me. This is the crux of your mistake. The equivalence principle talks about the inability to distinguish between uniform acceleration and a uniform gravitational field. You are applying the principle erroneously. It is not surprising that you are getting erroneous results. The nonuniform gravitational field produced by a point mass is everywhere nonuniform. That’s like trying to refute GR by referencing a paper on Newtonian mechanics. It proves nothing. People like you are dangerous. People who don't know math very well may see you spouting nonsense and not see that what you spout is nonsense. You showed us how to solve the problem incorrectly. I posted the link to show how the problem can be solved correctly.

Don't dismiss yourself so easily. Almost everyone can count; even crows can "count". But only the most gifted can grasp abstract mathematics on their own. For most of us, it takes quite a bit of education and a lot of practice to become proficient in math. As far as "proving" to your friend that the earth is not young, try some subtle hints rather than in-your-face arguments. Telling him you just read an interesting article on a 3.3 million baby protohuman: not subtle. Telling him there is an interesting exhibit on cave drawings at some local musuem: subtle.

Looking at your paper, Fig. 1. An inconsistency of general relativity. The drawing at left depicts a ball free to move within a relativistic rocket. The drawing at right depicts a ball in free fall within a uniform gravitational field above a planet. The equations in section 8 show that the ball can traverse the rocket vertically in either direction in an arbitrarily short time in the frame of its crew. Try again. In the frame of the crew (fixed with respect to the rocket), the ball takes more than [math]h/c[/math] time to traverse the rocket, where [math]h[/math] is the height of the rocket. Your principal mistake is a misinterpretation of the equivalence principle: According to general relativity’s equivalence principle, the crew experiences the equivalent of a uniform gravitational field. This is not quite right; the equivalence principle holds no experiment performed in a closed system can distinguish between an accelerated reference frame or a reference frame in a uniform gravitational field. You explicitly propagate this mistaken interpretation of the equivalence principle in section 1, where you equate the non-uniform gravitational field induced by a point mass to a uniform gravitational field. This is invalid. Your entire analysis hinges on this fatal flaw. For a proper analysis of the problem of a particle of negligible mass falling from rest at [math]r=\infty[/math] toward a point mass, see Voracek, P., "Relativistic gravitational potential and its relation to mass-energy", Astrophysics and Space Science, vol. 65, no. 2, Oct. 1979, p. 397-413. The theory of relativity is 90+ years old. Don't you think that this blatant flaw, should it exist, would have been uncovered by now?

Yes, we have. He misapplies the equivalence principle and proceeds from this point to assume a uniform gravitational field everywhere. According to the equivalence principle, the crew of a relativistic rocket experiences the equivalent of a uniform gravitational field. The equivalence principal only applies at a point. I do not see a single tensor equation in the paper. The equations of motion in general relativity are tensor equations. I do see a lot of hand-waving and misapplications of various equations. The free-fall velocity will asymptote to c, but this occurs at the Schwarzschild radius, not at r = 0.

Could a mirror based on a material with a negative index of refraction possibly work?

His idea was that someone on this forum would do his homework for him. It looks like he has the wrong idea.

It is a counter-intuitive result. Think about it this way. It takes smaller and smaller changes in the rope length to move the boat by the some fixed distance as [math]\theta\to\frac{\pi}2[/math]. The boat always moves faster than the rope.

Einstein's 1921 Nobel Prize was "for services to theoretical physics and especially for the discovery of the law of the photoelectric effect." The first part implicitly and rather vaguely recognizes his other works; 1921 was too soon for his work on general relativity. Evidence for special relativity did not appear until 1941, in the midst of World War II. Sweden was a neutral party to this war. Perhaps the Nobel Prize committee was playing politics. Perhaps they just screwed up. Its all a moot point. They can't award him posthumously.

Zanket, This deserves to be put into "Speculations" because it is a crackpot conjecture. Mods on other forums are a little less forgiving of crackpot notions. Yes, it does. You are using equation 17, which assumes the Minkowski metric over all space. This is an invalid assumption in the presence of a gravitational source. is based on inappropriately applying the Minkowski metric to all space. All your paper does is show an inconsistency between special and general relativity. BFD. Why do you think Einstein called one theory "special" (i.e., true only under special circumstances) and the other, "general"? General relativity yields special relativity in the limit [math]M\to0\text{\ or\ }r\to\infty[/math]. I have a feeling you’ll ignore that again though.

By exchange of virtual particles across the Schwarzschild radius. See question D.09 "How can gravity escape from a black hole?" in these FAQ.

Apparently you are not aware. The Schwarzschild metric applies outside the Schwarzschild radius. Equation 17 does not apply, from which your whole argument fails.

Use a single curved mirror. This works best (least distortion) when the curvature is limited to a small portion of the mirror (for example, a 90 degree bend in the middle of the mirror).

Equation 17 is from special relativity. It follows from the Minkowski metric for flat spacetime, [math]ds^2 = -c^2dt^2 + dr^2 + r^2d\theta^2 + r^2\sin^2\theta d\phi^2[/math] Quoting from the paper, Reader: Special relativity does not apply to curved spacetime. Author: It is used only in flat spacetime herein. It is indeed used, but that use is incorrect. From the paper, Let a test particle fall radially from rest at infinity toward a large point mass ... The Minkowski metric does not apply in such a case. The mass curves spacetime. The governing equations in the case of a point mass [math]M[/math] with zero angular momentum are the Schwarzschild metric, [math]ds^2 = -c^2\left(1-\frac{2GM}{c^2 r}\right)dt^2 + \left(1-\frac{2GM}{c^2 r}\right)^{-1} dr^2 + r^2d\theta^2 + r^2\sin^2\theta d\phi^2[/math] or by a misapplication of the Minkowski metric when the Schwarzschild metric should have been used instead. This thread belongs in "Speculations" with all of the other "I found a flaw in relativity" conjectures.

The gravitational force between two objects is a function of center of mass to center of mass only in the simplifying cases of point masses. The gravitational attraction on an orbiting spacecraft by the Earth varies as a satellite moves over mountains, oceans, etc. The Grace project measures these variations. The primary products of the project are sets of spherical harmonic gravity coefficients, to a ridiculously high order. If gravity was center of mass to center of mass, only the zeroth order coefficient (i.e., the mass) would be needed. An overview of Grace with a video is here: http://www.csr.utexas.edu/grace/gallery/animations/measurement/ From the video, "Since the earth has varied features such as mountains, valleys, and underground caverns, the mass is not evenly distributed around the globe. The "lumps" observed in the Earth's gravitational field result from an uneven distribution of mass inside the Earth."

Especially since the only math in the OP is flawed. TreborS: The entire underpinnings of the Gravity Recovery and Climate Experiment http://www.csr.utexas.edu/grace/ would be deeply flawed if gravitational attraction to a collection of objects could always be reduced to an acceleration to the center of mass of the objects.

TreborS Your argument has a basic flaw. You are using Newtonian gravity, in which the gravitational attraction to an object inside a spherical distribution of mass is zero. The universe appears to have a very even mass distribution. The net gravitational attraction of the rest of the universe on the Earth is essentially zero under Newtonian gravity. You have to go much more elaborate models of gravity to get something inertia out of gravity. Which is exactly what Einstein did with general relativity.

I too was in that big tent. Now we shall see which party is first to learn the wrong lesson from this election: Republicans thinking they lost because the republicans haven't been conservative enough in the last few years Democrats thinking they won because we, the people, lust for some far left utopian future. From what I have seen so far, the Democrats are well on the way to learning the wrong lesson. I am sure the Republicans are not too far behind.