The real twin paradox.
in [Relativity]
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From: colp on 25 Nov 2007 22:04 On Nov 26, 3:48 pm, Dono <sa...(a)comcast.net> wrote: > On Nov 25, 3:46 pm, colp <c...(a)solder.ath.cx> wrote: > > > Dirk's misdirects by describing the return leg in a way which is > > inconsistent with SR. > > Umm, no. SR describes time dilation. SR does not describe time compression. Dirk's description of time dilation: "While clock A is coasting, according to clock A, each tick on clock A is simultaneous with some tick on clock B with a smaller time value. " Dirk's description of time compression: "After clock A has made its turnaround, it has shifted to another inertial frame, in which according to clock A, each tick on clock A is simultaneous with some tick on clock B with a larger time value." > > > This misdirection serves to hide the paradox. > > Also no. SR must predict a total nil observed dilation for the entire experiment in order to avoid a paradox. By misreprenting the time value of the outgoing leg as larger rather then smaller as SR would predict, he gives the impression that the larger and smaller values cancel each other out to give a resultant nil dilation. > > > One could argue that switching reference frames half way through the > > experiment is another form of misdirection. > > Again, no. This argument is based on the fact that switching frames implies a loss of time simultaneity for the remote twin according to standard theory. > > > He has neither admitted not denied his error, and has resorted to > > insults in favour of arguments. > > http://www.catshoes.com/Tubes/Cartoons/Dumbo03.gif
From: Sue... on 26 Nov 2007 00:45 On Nov 25, 9:45 pm, colp <c...(a)solder.ath.cx> wrote: > On Nov 26, 3:31 pm, Dono <sa...(a)comcast.net> wrote: > > > > > > > > The error is his claim that relativistic time dilation is reversed on > > > the return leg of the experiment. > > > > From Dirk's opening post: > > > > When your two clocks fly apart, each clock will measure > > > this time to be longer and conclude that the other clock > > > is "running slower". > > > While clock A is coasting, according to clock A, each > > > tick on clock A is simultaneous with some tick on clock B > > > with a smaller time value. > > > While clock B is coasting, according to clock B, each > > > tick on clock B is simultaneous with some tick on clock A > > > with a smaller time value. > > > > After clock A has made its turnaround, it has shifted to > > > another inertial frame, in which according to clock A, each > > > tick on clock A is simultaneous with some tick on clock B > > > with a larger time value. > > > After clock B has made its turnaround, it has shifted to > > > another inertial frame, in which according to clock B, each > > > tick on clock B is simultaneous with some tick on clock A > > > with a larger time value. > > > Dirk is describing the Doppler effect piece to you,http://www.catshoes.com/Tubes/Cartoons/Dumbo03.gif > > Wrong. Here is the context: > > No, special relativity says much more precise than that > "moving clocks" are running slow. > > It says something about intertial observers who measure > times between ticks on remote, moving clocks. > > When your two clocks fly apart, each clock will measure > this time to be longer and conclude that the other clock > is "running slower". Put a light-clock which slows with motion on the traveler. Use it for inertial mass. http://www.bartleby.com/173/15.html http://en.wikipedia.org/wiki/Free_space http://www-ssg.sr.unh.edu/ism/what.html Also put a normal clock on the traveler. (or give her cable TV) Use that for causality and doppler calculation. ....Then you can have a solution for everyone without paradox. No need to mix them because light does not move inertially. <<A Lorentz transformation or any other coordinate transformation will convert electric or magnetic fields into mixtures of electric and magnetic fields, but no transformation mixes them with the gravitational field. >> http://www.aip.org/pt/vol-58/iss-11/p31.html << Light-quanta or with modern terminology, photons, were explicitly mentioned in the reports on which the prize decision rested only in connection with emission and absorption processes. The Committee says that the most important application of Einstein's photoelectric law and also its most convincing confirmation has come from the use Bohr made of it in his theory of atoms, which explains a vast amount of spectroscopic data. >> http://nobelprize.org/physics/articles/ekspong/index.html Sue...
From: Sue... on 26 Nov 2007 01:07 On Nov 26, 12:45 am, "Sue..." <suzysewns...(a)yahoo.com.au> wrote: [...] > > Also put a normal clock on the traveler. > (or give her cable TV) > Use that for causality and doppler calculation. BTW... An old synchronous motor clock with a very long cord works well here; unless someone can make a valid case that power cords have cycle thieves inside them. Sue... >
From: colp on 26 Nov 2007 03:43 On Nov 24, 11:27 am, Bryan Olson <fakeaddr...(a)nowhere.org> wrote: > colp wrote: > > Bryan Olson wrote: > >> Colp's theory is that somehow he gets the time-dilation of SR, but > >> the effect of changing inertial frames somehow does not count. > > > You are unable to show that the effect of changing inertial frames > > solves the paradox. > > Paradox solved here: > > <12q1j.19192$4V6.17...(a)newssvr14.news.prodigy.net> That is a link to this thread. You haven't show a solution. > > Part of SR that colp ignores, making his theory contradictory: > > http://www.bartleby.com/173/9.html Relativity of simultaneity is not relevant because the paradox can be demonstrated from a single frame of reference (the outgoing leg) which has spatial and tempoaral symmetry with the inbound leg. > > >> Colp's theory leads to a contradiction. > > > It's not my theory. It is standard special relativity. > > As we still lack any citation attributing the wrong theory to > anyone else, I stand by my description of it as Colp's own. The essential element of the paradox is time dilation as observed by one of the twins. This time dilation is standard SR http://en.wikipedia.org/wiki/Time_dilation > > >> In SR, the relativity of > >> simultaneity implies that each twin's view of his far-away sibling's > >> age changes upon the turn-around. > > > The turnaround cannot affect the observed time of the remote clock. > > A radio clock signal from the remote twin does not change just because > > the spacecraft rotates. > > "Turn-around" refers to change of direction, not orientation. Your statement is ambiguous. Please clarify.
From: Bryan Olson on 26 Nov 2007 04:38
colp wrote: > On Nov 24, 11:27 am, Bryan Olson <fakeaddr...(a)nowhere.org> wrote: >> colp wrote: >>> Bryan Olson wrote: >>>> Colp's theory is that somehow he gets the time-dilation of SR, but >>>> the effect of changing inertial frames somehow does not count. >>> You are unable to show that the effect of changing inertial frames >>> solves the paradox. >> Paradox solved here: >> >> <12q1j.19192$4V6.17...(a)newssvr14.news.prodigy.net> > > That is a link to this thread. You haven't show a solution. It's the message ID of the post. You can also find it at: http://groups.google.com/group/sci.physics.relativity/msg/1694288bbb6d6b21?hl=en >> Part of SR that colp ignores, making his theory contradictory: >> >> http://www.bartleby.com/173/9.html > > Relativity of simultaneity is not relevant because the paradox can be > demonstrated from a single frame of reference (the outgoing leg) which > has spatial and tempoaral symmetry with the inbound leg. Let's try that. Let's choose the outgoing frame of twin A as our inertial frame of reference, and stick to it. Note that given the outgoing/inbound symmetry you specify, the outgoing frame of one is the in inbound frame of the other. Outbound, twin A is in the frame of reference, so clock A runs normally. Twin B's is time-dilated to run slow. After they turn around (meaning reverse direction for the trip back), twin B is in our inertial frame of reference, and twin A is moving according to our frame of reference, making clock A run slow. We're not talking about what twin A observes; we sticking to our one chosen frame of reference, just as you suggested above. For each twin, one leg is in the frame of reference, the other is time dilated. They arrive back at Earth showing equal time having passed. Try sticking to any other single inertial frame of reference, and you'll get the same answer. So where is the paradox that you just said this should demonstrate? >>>> Colp's theory leads to a contradiction. >>> It's not my theory. It is standard special relativity. >> As we still lack any citation attributing the wrong theory to >> anyone else, I stand by my description of it as Colp's own. > > The essential element of the paradox is time dilation as observed by > one of the twins. This time dilation is standard SR > > http://en.wikipedia.org/wiki/Time_dilation If we stick to one inertial frame of reference, then there's no paradox. If we take a twin's point of view and change frames, we account for our far-away twin's age being different in the new frame, and once again there's no paradox. Only colp-theory says we can change inertial frames and somehow be immune to the relativity of simultaneity. Colp-theory makes no sense; it leads to contradictions. >>>> In SR, the relativity of >>>> simultaneity implies that each twin's view of his far-away sibling's >>>> age changes upon the turn-around. >>> The turnaround cannot affect the observed time of the remote clock. >>> A radio clock signal from the remote twin does not change just because >>> the spacecraft rotates. >> "Turn-around" refers to change of direction, not orientation. > > Your statement is ambiguous. Please clarify. Rotation is irrelevant. Turn-around refers to a twin changing direction: when the outbound leg is done, he turns around and heads back to Earth. That's when he changes inertial frames. What age does twin B reach simultaneously with twin A's turn-around? The answer is different in different frames. Let's not hear more nonsense about SR not saying such a thing, because look - there it is: http://www.bartleby.com/173/9.html -- --Bryan |