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Matterwave
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Breo said:Free falling observer measures proper time while Fiducial observer measures natural time?
What is natural time? All observers measure their own proper time.
Breo said:Free falling observer measures proper time while Fiducial observer measures natural time?
Per my post #29, fiducial observers define coordinate time for some chosen coordinates. There is nothing more 'natural' about this time than the proper time for any other observers. If you have coordinates based on a class of fiducial observers, coordinate time is proper time for those particular observers. Free fall observers measure their own proper time as well. All observers measure proper time.Breo said:Free falling observer measures proper time while Fiducial observer measures natural time?
Integral of the line element along the world line of any observer is proper time. Can you clarify your question, as this fact is like the 1+1=2 of relativity, so I am having a hard time believing this is what you are really asking.Breo said:After thinking a while about proper time. Can you give me an example with equations or not about how a frefo measures his proper time?
Breo said:After thinking a while about proper time. Can you give me an example with equations or not about how a frefo measures his proper time?
I'm glad you clarified, because that gives a more interesting question.Breo said:Yes, sure for a fiducial we take the time from integrating. But for a free falling observer... what formula gives the proper time.
Imagine you have ## e^0 = Adt -Bdx^i \\ e^i= Cdx^i ##
how to measure the proper time? in terms of the tetrad maybe?
Breo said:Yes, sure for a fiducial we take the time from integrating. But for a free falling observer... what formula gives the proper time.
Imagine you have ## e^0 = Adt -Bdx^i \\ e^i= Cdx^i ##
how to measure the proper time? in terms of the tetrad maybe?