Talk:Time dilation/Archive 2014

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Why is time dilation proven or even observed through atomic clock disparities?
Greetings! Let me introduce myself by saying that I try to sponge up as much physics and biology when ever I can. I am fascinated with everything from viral evolution to the research into neutrinos. But one thing I have a problem with and always had since I was a little child learning about the grandfather paradox is time travel and time dilation and thus the theory of relativity and its cousin special relativity. I am curious to why you would source that effects on atom clocks created by very fast travel proves time dilation. We merely use atom clocks and other types of clocks to measure time and always measure it incorrectly. We can even use our own brain and "count" the seconds to the best of our abilities.

With all the whacky quantum physics out there and the fact that speed directly affects many things why would it be proof that there has occured an actual time dilation just because atoms behaved diffrently? Haven't we seen evidence of that in certain scenarios of quantum mechanics the observation of particles changes their movement? Could then mere observation change time? It sounds silly and proves nothing in my opinion and I would love for someone to put in a little clarification in this article concerning this.

Please :)

46.59.34.174 (talk) 08:13, 22 November 2013 (UTC)


 * Note that this article talk page is not a place where we can chat about the subject and teach each other or help each other understanding aspects of the subject. THis is the place where we discuss the article structure, content and format. See wp:Talk page guidelines. You can submit questions like these on the wp:reference desk/science. Good luck. - DVdm (talk) 08:34, 22 November 2013 (UTC)


 * That's fine then, maybe I will, thanks. Still none of these sources prove any type of time dilation. Time is a dimension in the sense that within it something is measured. When the vibrations of a clock or the photons of a clock move slower or faster depending on outer circumstances then time has not been changed but perhaps still something significant: the very fabrics of our universe. Please, I cannot see how we can change a dimension, a measurment. We can change the time or in other words and according to wikipedia the interval between when two things happen but we can not or at least it has not been proven that we can change time itself or if it has could you please point me to a reference/page which explains it.


 * That is the suggestion would be that we have warped time or in other words that all things equal (photons and atoms being affected in the same way) one would move faster than the other in this warp. Is it not true to say that all these experiments cited show effects on various clocks and not on the dimension time itself? This may be a bit silly but please take a look at this short youtube video made to explain time dilation in simple terms: http://www.youtube.com/watch?v=UO6ERCzAjk0 It shows that the photon has a longer travelpath and thus takes more time to travel. What we call time dilation is not the dilation of time but merely the curving of a photon and what better place to start changing this terminology than here. Not on the basis of want but on the basis of fact and the fact that time does not change but a photons path changes!


 * PS: I undid your reversion of your own reply since I guess some clarification couldn't hurt.

46.59.34.174 (talk) 08:52, 22 November 2013 (UTC)


 * Your question on atomic clocks is answered by the fact that they are sealed units hence the method (and effect) of observing is the same regardless of velocity. The diagrams next to the section "Time dilation due to relative velocity symmetric between observers" show how the effect arises as a result of time being a dimension. The evidence for the validity of the prediction is given in Experimental Confirmation so as far as I can see, the page is adequate. You need to take some time to learn the physics before criticising, there are many sources available or message me if you want to discuss it further, this is not the place. George Dishman (talk) 12:53, 4 February 2014 (UTC)

"'Space' and 'Length'; 'Time' and 'Duration'" ; and "How Measurement of 'Time' is different from the measurement of 'Length'"
The terms: 'space' and 'time' need some clarification. What contracts in special-relativity is 'length' of 'physical-objects', not 'space'. What gets dilated in special-relativity is 'duration' of an 'event', not 'time'. 'Space' is there, and 'objects' are in 'space'; so a ruler can measure 'length' of an 'object'. Whereas 'time' is a 'mental-concept'; the 'duration-between-two-tiks-of-a-clock' is defined as a 'duration-of-one-second'; actually there is nothing like 'time'. Thus the so-called 'relativistic-time-dilation' means, 'extension-of-duration-of-an-event' as perceived by 'relativistically-moving-observers'. Such relativistic 'length-contraction' and 'time-dilation' can be alternatively-understood' as described in a recent paper:titled: "Wave-theoretical in-sight into the Relativistic length-contraction and time-dilation-of-super-nova-light-curves", by Hasmukh K. Tank, published in Advanced Studies in Theoretical Physics. Full-text PDF is freely available at: http://www.m-hikari.com/astp/astp2013/astp17-20-2013/tankASTP17-20-2013-2.pdf 123.201.19.201 (talk) 10:40, 19 November 2013 (UTC)


 * What contracts in special-relativity is neither the 'length' of 'physical-objects' nor 'space' but the measuremens thereof. For example if you have two rigid rods of length L separated by a gap of length G in the rest frame of the rods, those distances wll transform to F' and G' in a frame moving with respect to the first when the Lorentz Transforms are applied to the coordinates of the ends of the rods. George Dishman (talk) 12:54, 6 February 2014 (UTC)

Speed vs. Velocity
It seems that most of the discussion of velocity is really a discussion of speed. The difference is that velocity is a vector, which has direction. If the discussion were really about velocity, direction should enter the discussion. — Preceding unsigned comment added by 70.114.193.181 (talk) 16:59, 7 February 2013 (UTC)


 * In some cases in this article (eg; in Time dilation and Time dilation), velocity also stands for the (positive of negative) projection —a number— of the vector on a single axis. - DVdm (talk) 17:10, 7 February 2013 (UTC)


 * I don't know who started it, but speed is all that matters. The East and West-bound jets in the atomic clock experiments make the problem worse.  That was done simply to get two different speeds (+ or - Earth's rotation) for checking the equations.  A casual reader could get the idea that direction matters.  Free of other factors, it does not.  I think the use of v came from the derivation of the equation. Frank Layden (talk) 19:56, 19 November 2013 (UTC)

Speed is NOT "all that matters" in a discussion of time for an event. It is necessary to avoid vector mismatch when computing time from displacement and velocity. Using light forward propagation speed for a component of displacement skewed to that propagation produces an incorrect time. Using a proper velocity component of light for an accumulated displacement component produces the correct time. When vectors are matched properly, time is identical calculated by stationary and moving observers of a particular event in which light spans a particular displacement (see Physics Essays, Volume 27(1), 2014,pp 116-125. --Rsauerheber (talk) 19:53, 30 June 2014 (UTC)