Bremen 2017 – scientific programme

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GR: Fachverband Gravitation und Relativitätstheorie

GR 10: Alternative Ansätze

GR 10.1: Talk

Wednesday, March 15, 2017, 16:30–16:50, SFG 0150

The color of stars vs. the time dilation — •Shukri Klinaku — University of Prishtina, Kosovo

In 1842 Christian Doppler explaining the color of binary stars found the "wave-length Doppler effect". The "frequency Doppler effect" is also well-known. Analogously, we can successfully define the "energy Doppler effect", and the "time Doppler effect". We know that the color of stars changes for the observer on Earth, while for an observer in frame of reference on the star doesn't change. So the increasing and decreasing of frequency; the extension and contraction of wavelength; the increasing and decreasing of radiation energy; and the period dilation and period contraction are symmetric and they are dependent on relative velocity between the velocity of light (c) and velocity of its source (v). Thus if we want to express these changes (color, frequency, wavelength or radiation energy) in terms of time, then we use the "time Doppler effect", that means the change of the period of receiving signals. In other words, the time interval in the frame of moving source within n periods of emission (nTs) is quite equal to the time interval in the frame of observer on Earth which contains the same number n of the same periods: n(To + Ts v/c), where the second term in the sum inside brackets represents the time within which the first signal (from n signals) arrives to the observer. The story about the "length contraction" and "time dilation" overs here. The most tragic moment in all modern physics is the misinterpretation of the change of wavelength as "length contraction" and the misinterpretation of the change of periods as "time dilation".