JohnJBannan wrote:What don’t you get about the photon being timeless?

I get everything there is to get. I've been explaining it to you and it's obvious you're completely misunderstanding it. The timelessness of photons is a consequence of traveling at the speed of light (yes, even when they appear and disappear in a flash, they must still be traveling at the speed of light). When a thing travels at the speed of light, time is maximally dilated. That means, zero time goes by from the beginning of the travels to the end.

But here's the rub: there's only 0 time

for the thing travelling. For us who are watching the photon travel across the cosmos, it still takes thousands and thousands (or millions, or billions, etc.) of years to get from beginning to end (that's why it's called

relativity). Same is true for the photon appearing and disappearing in a flash. For an observer watching the photon appear and disappear, it takes time--an extremely brief period of time, but not zero.

But let's say, for the sake of argument, that you're right. Photons only ever exist by popping into existence and then popping out, and they do it so quickly, it's timeless--not just from their own perspective, not just from ours, but absolutely. Then I'm forced to accept it as a fact of nature--but it still doesn't make sense--appearing, existing, then disappearing? And no time goes by? Well, if that's the way the world works, I guess the world just doesn't make sense.

JohnJBannan wrote:You’re failing to appreciate the distinction between time and the indivisible unit of spacetime that creates time.

I must be, because the way you explain the distinction to me just doesn't make sense. You have me believing that your concept of this indivisible unit of spacetime is what spacetime is made of, like a wall is made of bricks, or water is made of H2O molecules. But I wouldn't say that when you divide space or time into smaller segments of space or time, they cease to be space or time. You can imagine a 1 meter cubed volume of space in your living room, right? It's a component, or building block, of the larger volume of your living room itself. Does the fact that it's a component of your living room's space mean it is not space itself? Now, it's possible that if you keep dividing time into every briefer periods, you eventually come to this fundamental unit that quantum physicists talk about. I don't see why just because it's the smallest piece it cease to be time. BUT... suppose that this smallest piece

is divisible after all, but it doesn't divide into shorter periods of time but into this indivisible unit that

you're thinking of--a sort of pre-time entity. Let's just say it divides into two such pieces. This seems consistent with what you've been saying--you don't get time with just one of these units but you do get time with a composite of them--so two? Ok, two it is. In this scenario, I just wouldn't have been describing it the way you have. I would have said there is a smallest unit of time which is 10^-33 seconds--and this is still time and it is not zero--but below this you get at most two of these pre-time entities which don't have a temporal duration but is still not zero because it's not a nothing. <-- If you had said this, it would have at least made some sense to me. I don't know if I would have believed it--I certainly don't think this is what scientists are saying--but we wouldn't get stuck on this point.

JohnJBannan wrote:In discrete time, there is a finite number of frames. In continuous time, there is an infinite number of frames.

I still don't get this. Why does discrete time mean there is a finite number of frames?

You must be thinking about a finite stretch of time--t0 to t1--and imagining the number of frames between t0 and t1. If time is discrete, then sure there can only be a finite number of them that fit between t0 and t1. And if time is continuous, well there are no fundamental units so you can fit as many as you want between t0 and t1. Ecmandu was right, you're pulling a Zeno.

But I'm not talking about t0 to t1; I'm talking about

all of time--and remember, I'm not convinced time had a beginning, so there is no t0 (probably no t1 either). In that scenario, you can fit as many discrete units of time as you want.