Known physics defeated by simple puzzle?
in [Relativity]
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From: Edward Green on 30 Mar 2010 17:28 On Mar 29, 5:53 pm, "Sue..." <suzysewns...(a)yahoo.com.au> wrote: > On Mar 29, 5:40 pm, Edward Green <spamspamsp...(a)netzero.com> wrote: > > > > > On Feb 15, 8:11 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > <...> > > > > As I say, I don't think it is wrong. Relativity clearly works - or at > > > least to a sufficiently precise approximation. The point is that no > > > one seems to be able to explain some of its more esoteric assumptions > > > in physical terms - such as the constant speed of light no matter what > > > the velocity of the observer. > > > That's easy. Sort of. Physical processes propagate at (at most) the > > speed of light. This includes the processes which hold matter > > together. A given inertial observer watching a second relatively > > moving observe measure the "constant" speed of light concludes that > > the second observer's matter has shrunk in the direction of travel and > > his clocks have slowed, just so as to cause him to measure a constant > > speed of light. In straight SR, with complete Lorentz invariance, the > > situation is completely reciprocal. > > ============== > > > > > Mind you I haven't explained in detail how the dependence of the > > cohesion of matter on the speed of light causes this relative > > shrinking and slowing, but that's the gist of the physical argument > > why, against all odds, observers in relative inertial motion measure > > an invariant speed of light. > > <<In 1907 Einstein criticized the "ad hoc" character > of Lorentz's contraction hypothesis in his theory of > electrons, because according to him it was only > invented to rescue the hypothesis of an immobile ether. > Einstein thought it necessary to replace Lorentz's > theory of electrons by assuming that Lorentz's > "local time" can simply be called "time", and he > stated that the immobile ether as the theoretical > fundament of electrodynamics was unsatisfactory. >> http://en.wikipedia.org/wiki/Lorentz_ether_theory That's Einstein's problem. Mind you (who did I just pick up that annoying turn of phrase from?), I haven't necessarily resurrected the immobile aether, but if we stop at Einstein's dismissal, we will be left forever wondering just how this magic of a constant speed of light works. The devil is in the details, but _something_ like Lorentz contraction is going on, even if the "contraction" is completely reciprocal among frames. And mind you, it might not be, although it's a damn good approximation, apparently. > << where epsilon_0 and mu_0 are physical constants which > can be evaluated by performing two simple experiments > which involve measuring the force of attraction between > two fixed charges and two fixed parallel current carrying > wires. According to the relativity principle, these experiments > must yield the same values for epsilon_0 and mu_0 in all > inertial frames. Thus, the speed of light must be the > same in all inertial frames. >>http://farside.ph.utexas.edu/teaching/em/lectures/node108.html Well, that's one species of explanation. I don't see it as necessarily in conflict with mine (which I admit is rather vague at this point). Better watch it. You are starting to give relevant quotes. :-) :-) :-)
From: Sue... on 30 Mar 2010 18:18 On Mar 30, 5:28 pm, Edward Green <spamspamsp...(a)netzero.com> wrote: > On Mar 29, 5:53 pm, "Sue..." <suzysewns...(a)yahoo.com.au> wrote: > > > > > On Mar 29, 5:40 pm, Edward Green <spamspamsp...(a)netzero.com> wrote: > > > > On Feb 15, 8:11 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > <...> > > > > > As I say, I don't think it is wrong. Relativity clearly works - or at > > > > least to a sufficiently precise approximation. The point is that no > > > > one seems to be able to explain some of its more esoteric assumptions > > > > in physical terms - such as the constant speed of light no matter what > > > > the velocity of the observer. > > > > That's easy. Sort of. Physical processes propagate at (at most) the > > > speed of light. This includes the processes which hold matter > > > together. A given inertial observer watching a second relatively > > > moving observe measure the "constant" speed of light concludes that > > > the second observer's matter has shrunk in the direction of travel and > > > his clocks have slowed, just so as to cause him to measure a constant > > > speed of light. In straight SR, with complete Lorentz invariance, the > > > situation is completely reciprocal. > > > ============== > > > > Mind you I haven't explained in detail how the dependence of the > > > cohesion of matter on the speed of light causes this relative > > > shrinking and slowing, but that's the gist of the physical argument > > > why, against all odds, observers in relative inertial motion measure > > > an invariant speed of light. > > > <<In 1907 Einstein criticized the "ad hoc" character > > of Lorentz's contraction hypothesis in his theory of > > electrons, because according to him it was only > > invented to rescue the hypothesis of an immobile ether. > > Einstein thought it necessary to replace Lorentz's > > theory of electrons by assuming that Lorentz's > > "local time" can simply be called "time", and he > > stated that the immobile ether as the theoretical > > fundament of electrodynamics was unsatisfactory. > >>http://en.wikipedia.org/wiki/Lorentz_ether_theory > > That's Einstein's problem. Mind you (who did I just pick up that > annoying turn of phrase from?), I haven't necessarily resurrected the > immobile aether, =============== > but if we stop at Einstein's dismissal, we will be > left forever wondering just how this magic of a constant speed of > light works. Why not wait 'till Newton's light corpuscles are discovered before getting your knickers in a knot over it. << where epsilon_0 and mu_0 are physical constants which can be evaluated by performing two simple experiments which involve measuring the force of attraction between two fixed charges and two fixed parallel current carrying wires. According to the relativity principle, these experiments must yield the same values for epsilon_0 and mu_0 in all inertial frames. Thus, the speed of light must be the same in all inertial frames. >> http://farside.ph.utexas.edu/teaching/em/lectures/node108.html > The devil is in the details, but _something_ like > Lorentz contraction is going on, even if the "contraction" is > completely reciprocal among frames. And mind you, it might not be, > although it's a damn good approximation, apparently. > In relativity, only the pseudo-space contracts for calculating purposes. Same as AC circuit theory. http://en.wikipedia.org/wiki/Complex_number > > Well, that's one species of explanation. I don't see it as > necessarily in conflict with mine (which I admit is rather vague at > this point). You might avoid some other conflicts perusing these two pages. I sense the particle is wagging the dogged. http://nobelprize.org/nobel_prizes/physics/articles/ekspong/ http://en.wikipedia.org/wiki/Photoelectric_effect#Modern_view > > Better watch it. You are starting to give relevant quotes. :-) :-) :-) My parents were the same way. Just as I was putting adolescence behind they got smarter almost overnight. Sue...
From: spudnik on 30 Mar 2010 18:31 exactly, what I say, when someone mentions the "peri-WW2 cache of Roswell, New Mexico, other than the balsa-wood-and-aluminized-mylar- and-weather-balloon junkpile" (the actual, missing shrine of UFOlogy .-) "Duh?" > Off topic again Sue .. we are discussing SR. --They didn't follow that money! http://tarpley.net/bush12.htm
From: Ste on 31 Mar 2010 06:16 On 29 Mar, 22:40, Edward Green <spamspamsp...(a)netzero.com> wrote: > On Feb 15, 8:11 am, Ste <ste_ro...(a)hotmail.com> wrote: > > <...> > > > As I say, I don't think it is wrong. Relativity clearly works - or at > > least to a sufficiently precise approximation. The point is that no > > one seems to be able to explain some of its more esoteric assumptions > > in physical terms - such as the constant speed of light no matter what > > the velocity of the observer. > > That's easy. Sort of. Physical processes propagate at (at most) the > speed of light. This includes the processes which hold matter > together. A given inertial observer watching a second relatively > moving observe measure the "constant" speed of light concludes that > the second observer's matter has shrunk in the direction of travel and > his clocks have slowed, just so as to cause him to measure a constant > speed of light. In straight SR, with complete Lorentz invariance, the > situation is completely reciprocal. Unfortunately, this explanation has previously foundered when I've asked whether this "contraction" is real or apparent.
From: Inertial on 31 Mar 2010 08:13
"Ste" <ste_rose0(a)hotmail.com> wrote in message news:1a763a4d-f2be-4d9c-b38e-75432d145743(a)15g2000yqi.googlegroups.com... > On 29 Mar, 22:40, Edward Green <spamspamsp...(a)netzero.com> wrote: >> On Feb 15, 8:11 am, Ste <ste_ro...(a)hotmail.com> wrote: >> >> <...> >> >> > As I say, I don't think it is wrong. Relativity clearly works - or at >> > least to a sufficiently precise approximation. The point is that no >> > one seems to be able to explain some of its more esoteric assumptions >> > in physical terms - such as the constant speed of light no matter what >> > the velocity of the observer. >> >> That's easy. Sort of. Physical processes propagate at (at most) the >> speed of light. This includes the processes which hold matter >> together. A given inertial observer watching a second relatively >> moving observe measure the "constant" speed of light concludes that >> the second observer's matter has shrunk in the direction of travel and >> his clocks have slowed, just so as to cause him to measure a constant >> speed of light. In straight SR, with complete Lorentz invariance, the >> situation is completely reciprocal. > > Unfortunately, this explanation has previously foundered when I've > asked whether this "contraction" is real or apparent. I think it is your understanding that foundered. Just as different observers can measure different speeds for the same object, they can measure different length for it. Those different speeds are as real as the different lengths. Why is that so hard to understand? |