Time\'s Arrow (General)

by dhw, Thursday, May 01, 2014, 14:32 (3858 days ago) @ David Turell

Dhw: I don't understand how "the speed of light" can be reconciled with "time does not pass". Surely you cannot have speed without time, and we all know that whatever we see is past, because it depends precisely on the speed of light. If I look at a star, I will see it as it was x light years ago. Can you please explain, then, how light can be called timeless? -DAVID: Einstein imagined moving away from a clock at the speed of light. The hands never changed position. Time is stopped. Proven in satellites.-ROMANSH: Regarding time in theory of relativity ... My understanding it [relativity] can be expressed without the dimension of time. Which of course is difficult for someone like me who is firmly stuck in a Euclidean universe that has a Newtonian clock ticking away.-I sympathize (unusually!) with Romansh, and I hesitate to ask these questions, David, of you and Einstein, but I am here to learn. I did as Einstein told me, but I'm assured by my fellow earthlings that the hands of the clock went on changing position. It's I the observer who thought the hands never moved, because what I observed depended on my position in relation to the object I was observing and the speed at which I was moving. In other words, if I stopped moving, wouldn't I see the hands of the clock changing, though offering a time relative to where I am positioned? Do these experts mean that if there is no observer, there is no time? Surely not. A supernova explosion will take place whether observed or not (and presumably did before life began), which inevitably entails a past leading up to the explosion. Swenson wrote: "I don't pretend to know how tomorrow can exist simultaneously with today and yesterday. But at the speed of light they actually and rigorously do. Time does not pass." I can see how observers of time can telescope yesterday and today, though I'm not sure about tomorrow. But can you please explain to me how time itself can be telescoped?