The real twin paradox.
in [Relativity]
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From: bz on 29 Nov 2007 08:25 "Sue..." <suzysewnshow(a)yahoo.com.au> wrote in news:80872278-f968-454b-a5d5-b520372179cf(a)s12g2000prg.googlegroups.com: > On Nov 29, 4:40 am, bz <bz+...(a)ch100-5.chem.lsu.edu> wrote: >> "Sue..." <suzysewns...(a)yahoo.com.au> wrote in >> news:2141a9a7-70f6-4527-a1fa- >> e931094c4...(a)j44g2000hsj.googlegroups.com: ..... > > Your problem is that; > I don't believe spacetime displacememts can > become temporal displacements just because BZ and H.G Wells would > like it to be true. :-) It is not a matter of what BZ would like to be true. It is a matter of wanting to KNOW what is true. You, on the other hand, seems to think you KNOWS what is true and want everyone else to join your sect. I won't drink the cool-aid. I am not convinced by tangential thrusts, citations that are only related to the subject at hand in that they discuss physics and have a few of the key words somewhere in them. In any case, the 'currently accepted' view seems to be that the traveling twin would return younger than his stay at home sister. You, on the other hand 'state as if it were an accepted fact' the hypothesis that the observed effects have a different explanation and that there would be no difference in biological age nor in time kept by any clock except a light clock. May I suggest that if you took the approach "Many believe ... but I have reason to believe ..., hopefully an experiment will soon show which is right", you might have greater credibility, at least with me. I also suggest you stop 'correcting' statements which correctly state either Einstein's 1905, 1920, or other commonly held ideas of SR or GR as if such statements were KNOWN to be wrong. It is perfectly all right to say 'that is correct according to Einstein's 1905 paper. In later revisions the idea was changed to .... And now there are even some that believe ....' There are, of course, some things KNOWN to be wrong, such as Newton's Laws of physics, that are still quite useful. Pointing out WHEN these laws fail and others MUST be used to get CORRECT answers IS valuable. -- bz please pardon my infinite ignorance, the set-of-things-I-do-not-know is an infinite set. bz+spr(a)ch100-5.chem.lsu.edu remove ch100-5 to avoid spam trap
From: Daryl McCullough on 29 Nov 2007 10:58 Sue... says... >The page shows a young twin beside an old twin after >one twin has traveled. >Does one of the twins have a medical disorder or is the page >it offering argument against the principle of relativity? One twin looks older because he is *older*. He has lived longer. The "time" that is important for physical processes is not coordinate time, but *proper* time. ><< The general principle of relativity states that physical >laws are the same in all reference frames -- inertial or non- >inertial.>> >http://en.wikipedia.org/wiki/Principle_of_relativity Yes, and what those laws say is that the amount of aging of any twin is equal to the proper time since he is born, where proper time is computed by: tau = integral of square-root(g_uv dx^u dx^v) -- Daryl McCullough Ithaca, NY
From: Sue... on 29 Nov 2007 11:19 On Nov 29, 8:25 am, bz <bz+...(a)ch100-5.chem.lsu.edu> wrote: > "Sue..." <suzysewns...(a)yahoo.com.au> wrote innews:80872278-f968-454b-a5d5-b520372179cf(a)s12g2000prg.googlegroups.com: > > > > > On Nov 29, 4:40 am, bz <bz+...(a)ch100-5.chem.lsu.edu> wrote: > >> "Sue..." <suzysewns...(a)yahoo.com.au> wrote in > >> news:2141a9a7-70f6-4527-a1fa- > >> e931094c4...(a)j44g2000hsj.googlegroups.com: > .... > > > Your problem is that; > > I don't believe spacetime displacememts can > > become temporal displacements just because BZ and H.G Wells would > > like it to be true. :-) > > It is not a matter of what BZ would like to be true. > > It is a matter of wanting to KNOW what is true. > > You, on the other hand, seems to think you KNOWS what is true and want > everyone else to join your sect. I won't drink the cool-aid. > I am not convinced by tangential thrusts, citations that are only related > to the subject at hand in that they discuss physics and have a few of the > key words somewhere in them. > > In any case, the 'currently accepted' view seems to be that the traveling > twin would return younger than his stay at home sister. You, on the other > hand 'state as if it were an accepted fact' the hypothesis that the > observed effects have a different explanation and that there would be no > difference in biological age nor in time kept by any clock except a light > clock. I won't deny that is a *popular* view that you can support with citations from many long established schools. But they don't square all four corners and there are plenty of credible sources that explain why and DO square all four corners. > > May I suggest that if you took the approach "Many believe ... but I have > reason to believe ..., hopefully an experiment will soon show which is > right", you might have greater credibility, at least with me. > See above. > I also suggest you stop 'correcting' statements which correctly state > either Einstein's 1905, 1920, or other commonly held ideas of SR or GR as > if such statements were KNOWN to be wrong. > I don't, if a URL is offered so the context can be seen. Many of his statements about some particular clock are absurd out of context but are quite rational when taken in relation to other clocks in an illustration. > It is perfectly all right to say 'that is correct according to Einstein's > 1905 paper. In later revisions the idea was changed to .... And now there > are even some that believe ....' > > There are, of course, some things KNOWN to be wrong, such as Newton's Laws > of physics, that are still quite useful. Pointing out WHEN these laws fail > and others MUST be used to get CORRECT answers IS valuable. If I was interviewing a college graduate for a job, I wouldn't refuse to consider his most recent 15 years of academic achievement. Likewise, I give Einstein the mulligan rather than wannabe time travelers that insist on the 1905 paper over the 1920 which benefits from his experience in developing GR and his confrontation with the paradox by Langevin and others. << Pseudoscience relies heavily on anachronistic thinking. The older the idea, the more attractive it is to pseudoscience--it's the wisdom of the ancients!--especially if the idea is transparently wrong and has long been discarded by science. >> http://www.quackwatch.org/01QuackeryRelatedTopics/pseudo.html Sue... > > -- > bz > > please pardon my infinite ignorance, the set-of-things-I-do-not-know is an > infinite set. > > bz+...(a)ch100-5.chem.lsu.edu remove ch100-5 to avoid spam trap
From: Daryl McCullough on 29 Nov 2007 11:31 colp says... > >On Nov 29, 1:32 pm, stevendaryl3...(a)yahoo.com (Daryl McCullough) >wrote: >> If you want to show that that formula is applicable, >> then *derive* it from the postulates of Special Relativity. > >You are making the claim. The burden of proof is yours, not mine. What? You are making the claim that relativity is contradictory. If that's true, then *derive* a contradiction from the postulates of relativity. If you can't do it, (and obviously, you can't), then what basis do you have for saying that it is contradictory? -- Daryl McCullough Ithaca, NY
From: Sue... on 29 Nov 2007 12:10
On Nov 29, 10:58 am, stevendaryl3...(a)yahoo.com (Daryl McCullough) wrote: > Sue... says... > > >The page shows a young twin beside an old twin after > >one twin has traveled. > >Does one of the twins have a medical disorder or is the page > >it offering argument against the principle of relativity? > > One twin looks older because he is *older*. He has lived longer. > > The "time" that is important for physical processes is not > coordinate time, but *proper* time. Proper time is the appearace of a distant clock. That can have no influence on phenomena aboard the ship. ....Unless you are holding to Newton's concept of an inertial ether. As I have mentioned previously you are making a splendid argument in its favor. > > ><< The general principle of relativity states that physical > >laws are the same in all reference frames -- inertial or non- > >inertial.>> > >http://en.wikipedia.org/wiki/Principle_of_relativity > > Yes, and what those laws say is that the amount of aging > of any twin is equal to the proper time since he is born, > where proper time is computed by: > > tau = integral of square-root(g_uv dx^u dx^v) > Ah... I don't find that interpretation on the page. My browser finds about 5 occurance of pAGE but no occurance of AGE. Sue... > -- > Daryl McCullough > Ithaca, NY |