Mutual time slowdown means both clocks go slow
in [Relativity]
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From: artful on 7 Aug 2010 03:01 On Aug 7, 4:15 pm, BURT <macromi...(a)yahoo.com> wrote: > On Aug 6, 11:10 pm, Bernhard Schornak <schor...(a)web.de> wrote: > > > Hint: > > > If the train is really fast (574 km/h is the current > > record), you can't read clocks outside the train and > > no one outside can read a clock inside it. With that > > speed, a clock rushes by much faster than anyone can > > read it. > > > Greetings from Augsburg > > > Bernhard Schornak > > Still it could be photographed. Make sure you include that as part of the process that a passenger can use to measure the ticking rate of the station clock. If you ever decide to provide an answer.
From: artful on 7 Aug 2010 03:19 On Aug 7, 5:00 pm, Bernhard Schornak <schor...(a)web.de> wrote: > BURT wrote: > > Bernhard Schornak wrote: > >> Hint: > > >> If the train is really fast (574 km/h is the current > >> record), you can't read clocks outside the train and > >> no one outside can read a clock inside it. With that > >> speed, a clock rushes by much faster than anyone can > >> read it. > > >> Greetings from Augsburg > > >> Bernhard Schornak > > > Still it could be photographed. > > Yes. By whom? How fast can you shoot a pic- > ture and compare it against your clock? > > What kind of clocks are on the platform and > in the train? To measure any difference, it > requires very fast clocks (somewhere in the > range of Gigahertz or above). > > Did you put the Dopplereffect into account? > > Might be a better idea to wait for the next > station and read both clocks as long as the > train does not move. > > Greetings from Augsburg > > Bernhard Schornak This is a gedanken .. we can assume we have clocks that are accurate enough and can be read, and then when an observer is directly adjacent to a clock, he can read the time correctly and 'instantly'. But BURT still needs to come up with his method of how to determine the rate of the station clock. As understanding that is critical to understanding what time dilation means
From: Bernhard Schornak on 7 Aug 2010 05:14 artful wrote: > Bernhard Schornak wrote: >> BURT wrote: >>> Bernhard Schornak wrote: >>>> Hint: >> >>>> If the train is really fast (574 km/h is the current >>>> record), you can't read clocks outside the train and >>>> no one outside can read a clock inside it. With that >>>> speed, a clock rushes by much faster than anyone can >>>> read it. >> >> >>> Still it could be photographed. >> >> Yes. By whom? How fast can you shoot a pic- >> ture and compare it against your clock? >> >> What kind of clocks are on the platform and >> in the train? To measure any difference, it >> requires very fast clocks (somewhere in the >> range of Gigahertz or above). >> >> Did you put the Dopplereffect into account? >> >> Might be a better idea to wait for the next >> station and read both clocks as long as the >> train does not move. > > This is a gedanken .. we can assume we have clocks that are accurate > enough and can be read, and then when an observer is directly adjacent > to a clock, he can read the time correctly and 'instantly'. But BURT > still needs to come up with his method of how to determine the rate of > the station clock. As understanding that is critical to understanding > what time dilation means It is a problem of plausibility - real trains move at speeds, where no relativistic effects could be measured (it is beyond our technical abilities), while trains moving with one half the speed of light (or even more) aren't very realistic - they would lift off and leave the orbit. What we can measure with really high accuracy is the Dopplereffect - light is compressed if objects move towards each other and stretched if they move away from each other. Hence, the red- or blue-shift of a moving train could be used to determine time dilation or contration with _some_ precision. Probably it is cheaper than to use high precision clocks. Time dela- tion at 574 km/h must be in the range of some femtoseconds (just guessed)? Greetings from Augsburg Bernhard Schornak
From: artful on 7 Aug 2010 08:25 On Aug 7, 7:14 pm, Bernhard Schornak <schor...(a)web.de> wrote: > artful wrote: > > Bernhard Schornak wrote: > >> BURT wrote: > >>> Bernhard Schornak wrote: > >>>> Hint: > > >>>> If the train is really fast (574 km/h is the current > >>>> record), you can't read clocks outside the train and > >>>> no one outside can read a clock inside it. With that > >>>> speed, a clock rushes by much faster than anyone can > >>>> read it. > > >>> Still it could be photographed. > > >> Yes. By whom? How fast can you shoot a pic- > >> ture and compare it against your clock? > > >> What kind of clocks are on the platform and > >> in the train? To measure any difference, it > >> requires very fast clocks (somewhere in the > >> range of Gigahertz or above). > > >> Did you put the Dopplereffect into account? > > >> Might be a better idea to wait for the next > >> station and read both clocks as long as the > >> train does not move. > > > This is a gedanken .. we can assume we have clocks that are accurate > > enough and can be read, and then when an observer is directly adjacent > > to a clock, he can read the time correctly and 'instantly'. But BURT > > still needs to come up with his method of how to determine the rate of > > the station clock. As understanding that is critical to understanding > > what time dilation means > > It is a problem of plausibility - real trains > move at speeds, where no relativistic effects > could be measured (it is beyond our technical > abilities), while trains moving with one half > the speed of light (or even more) aren't very > realistic - they would lift off and leave the > orbit. > > What we can measure with really high accuracy > is the Dopplereffect - light is compressed if > objects move towards each other and stretched > if they move away from each other. Hence, the > red- or blue-shift of a moving train could be > used to determine time dilation or contration > with _some_ precision. Probably it is cheaper > than to use high precision clocks. Time dela- > tion at 574 km/h must be in the range of some > femtoseconds (just guessed)? > > Greetings from Augsburg > > Bernhard Schornak No .. its nothing to do with plausibility .. its a gedanken.
From: Bernhard Schornak on 7 Aug 2010 09:55
artful wrote: > Bernhard Schornak wrote: >> artful wrote: >>> Bernhard Schornak wrote: >>>> BURT wrote: >>>>> Bernhard Schornak wrote: >>>>>> Hint: >> >>>>>> If the train is really fast (574 km/h is the current >>>>>> record), you can't read clocks outside the train and >>>>>> no one outside can read a clock inside it. With that >>>>>> speed, a clock rushes by much faster than anyone can >>>>>> read it. >> >>>>> Still it could be photographed. >> >>>> Yes. By whom? How fast can you shoot a pic- >>>> ture and compare it against your clock? >> >>>> What kind of clocks are on the platform and >>>> in the train? To measure any difference, it >>>> requires very fast clocks (somewhere in the >>>> range of Gigahertz or above). >> >>>> Did you put the Dopplereffect into account? >> >>>> Might be a better idea to wait for the next >>>> station and read both clocks as long as the >>>> train does not move. >> >>> This is a gedanken .. we can assume we have clocks that are accurate >>> enough and can be read, and then when an observer is directly adjacent >>> to a clock, he can read the time correctly and 'instantly'. But BURT >>> still needs to come up with his method of how to determine the rate of >>> the station clock. As understanding that is critical to understanding >>> what time dilation means >> >> It is a problem of plausibility - real trains >> move at speeds, where no relativistic effects >> could be measured (it is beyond our technical >> abilities), while trains moving with one half >> the speed of light (or even more) aren't very >> realistic - they would lift off and leave the >> orbit. >> >> What we can measure with really high accuracy >> is the Dopplereffect - light is compressed if >> objects move towards each other and stretched >> if they move away from each other. Hence, the >> red- or blue-shift of a moving train could be >> used to determine time dilation or contration >> with _some_ precision. Probably it is cheaper >> than to use high precision clocks. Time dela- >> tion at 574 km/h must be in the range of some >> femtoseconds (just guessed)? > > No .. its nothing to do with plausibility .. its a gedanken. As in thought experiment? Well, I do not really like gedanken like that, they're quit stupid. How about a rocket flying over an airbase, where a _big_ clock is on the ground and a huge LED display is on the rocket (tip to wing)? The Helios space probes reached a speed of 70.2 km/h (0.000234 c)... Greetings from Augsburg Bernhard Schornak |