The real twin paradox.
in [Relativity]
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From: Sue... on 29 Nov 2007 13:16 On Nov 29, 12:10 pm, "Sue..." <suzysewns...(a)yahoo.com.au> wrote: > 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) In GR it is completely rational to grid a region of space as Newton's ether so its volume can has a relationship to electromagnetic energy or the equivalent mass. That is how inertia enters the field equations. But it is completly unnecessary to hold SR's postulates to a Newtonian space to resolve a conflict that does not even exist and is already resolved in classical EM. That may be unclear, even in the 1920 paper << in reality there is not the least incompatibility between the principle of relativity and the law of propagation of light >> http://www.bartleby.com/173/7.html but is seems perfectly clear in Weinberg's statement: <<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 Sue... > > 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- Hide quoted text - > > - Show quoted text -
From: Daryl McCullough on 29 Nov 2007 14:22 Sue... says... > >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. It's hard to imagine a more incorrect answer than that. No, that's completely wrong. Proper time is the time shown on a *local* clock. Look at your watch. Note the time. Now walk a couple of blocks and look at your watch again. The difference in the two times is the proper time for the path that you just took. It doesn't have anything to do with distant clocks. -- Daryl McCullough Ithaca, NY
From: Sue... on 29 Nov 2007 14:39 On Nov 29, 2:22 pm, stevendaryl3...(a)yahoo.com (Daryl McCullough) wrote: > Sue... says... > > > > > > > > >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. > > It's hard to imagine a more incorrect answer than that. > No, that's completely wrong. Proper time is the time > shown on a *local* clock. Look at your watch. Note > the time. Now walk a couple of blocks and look at > your watch again. The difference in the two times is > the proper time for the path that you just took. > > It doesn't have anything to do with distant clocks. << A clock in a moving frame will be seen to be running slow, or "dilated" according to the Lorentz transformation. The time will always be shortest as measured in its rest frame. The time measured in the frame in which the clock is at rest is called the "proper time". >> http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/tdil.html It's a good job my temper isn't as short as your memory. That is in the 1920 paper and both were quoted to you yesterday. If you haven't heard that Roosevelt lost to Taft then maybe you've been on a long voyage and there really is something to this time travel thing. :o) Sue... > > -- > Daryl McCullough > Ithaca, NY- Hide quoted text - > > - Show quoted text -
From: Daryl McCullough on 29 Nov 2007 15:35 Sue... says... > >On Nov 29, 2:22 pm, stevendaryl3...(a)yahoo.com (Daryl McCullough) >wrote: >> Sue... says... >> >Proper time is the appearace of a distant clock. >> >> It's hard to imagine a more incorrect answer than that. >> No, that's completely wrong. Proper time is the time >> shown on a *local* clock. Look at your watch. Note >> the time. Now walk a couple of blocks and look at >> your watch again. The difference in the two times is >> the proper time for the path that you just took. >> >> It doesn't have anything to do with distant clocks. > ><< A clock in a moving frame will be seen to be >running slow, or "dilated" according to the Lorentz >transformation. The time will always be shortest as >measured in its rest frame. The time measured in the >frame in which the clock is at rest is called the >"proper time". >> >http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/tdil.html Proper time, as it says right there is the time measured in the frame in which the clock is at rest. It has nothing to do with distant clocks. As usual, you have no idea what you are talking about. -- Daryl McCullough Ithaca, NY
From: Daryl McCullough on 29 Nov 2007 15:41
Sue... says... > >On Nov 29, 2:22 pm, stevendaryl3...(a)yahoo.com (Daryl McCullough) >wrote: >Sue wrote: >> >Proper time is the appearace of a distant clock. >> >> It's hard to imagine a more incorrect answer than that. >> No, that's completely wrong. Proper time is the time >> shown on a *local* clock. Look at your watch. Note >> the time. Now walk a couple of blocks and look at >> your watch again. The difference in the two times is >> the proper time for the path that you just took. >> >> It doesn't have anything to do with distant clocks. > ><< A clock in a moving frame will be seen to be >running slow, or "dilated" according to the Lorentz >transformation. The time will always be shortest as >measured in its rest frame. The time measured in the >frame in which the clock is at rest is called the >"proper time". >> >http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/tdil.html I have no idea why you think that passage supports your claim. Here's another article that explains what I was saying: http://www.iep.utm.edu/ancillaries/Proper-Time.htm "Proper time is also called clock time, or process time. It is a measure of the amount of physical process that a system undergoes. E.g. proper time for an ordinary mechanical clock is recorded by the number of rotations of the hands of the clock." As usual, you have no idea what you are talking about. -- Daryl McCullough Ithaca, NY |