Time Travel... the fly in the ointment

[bilby]

The idea that the past and the future exist is the idea that time is a dimension similar to a space dimension. I don't see where there is any logical problem with this idea.

There is certainly a terminological problem. According to the idea that time is a dimension similar to a space dimension, if the past and the future exist they of course don't exist at the same time as the present, or as each other. Yet, all times would somehow exist together to make this space-like dimension. We still have to say that the past existed, that the future will exist etc. Yet, past, present and future form just one entity, the time dimension. Then the whole space-time is still. It's not changing at all.
EB

According to the video presented in this thread the claim is that the past and future do exist at the same time as the present.

The thought experiment was of some distant alien traveling towards earth at such a speed that it's "slice of now" becomes "tilted" and to that alien the past of earth is as real as the present of the alien.

So the entire past of earth is just sitting somewhere so that a distant alien could include any bit of it in that alien's "slice of now".

Space and time are relative. There are no preferred reference frames; a point in the past from the perspective of one observer may be a point in in the future from another perspective.

One way to understand this is to consider time as a dimension; the four dimensional entity that is spacetime is unchanging, and observers move through it, giving them the illusion of change.

 

[Speakpigeon]

The idea that the past and the future exist is the idea that time is a dimension similar to a space dimension. I don't see where there is any logical problem with this idea.

There is certainly a terminological problem. According to the idea that time is a dimension similar to a space dimension, if the past and the future exist they of course don't exist at the same time as the present, or as each other. Yet, all times would somehow exist together to make this space-like dimension. We still have to say that the past existed, that the future will exist etc. Yet, past, present and future form just one entity, the time dimension. Then the whole space-time is still. It's not changing at all.
EB

According to the video presented in this thread the claim is that the past and future do exist at the same time as the present.

If your claim is that some scientist is hopeless at conveying scientific ideas through common language then you may have a point but this a difficult exercise.

The thought experiment was of some distant alien traveling towards earth at such a speed that it's "slice of now" becomes "tilted" and to that alien the past of earth is as real as the present of the alien.

So what? Where's the logical flaw?

So the entire past of earth is just sitting somewhere so that a distant alien could include any bit of it in that alien's "slice of now".

To say that the entire past of earth is just sitting somewhere is somewhat misleading. If that's what the video says, bad for them. If it's only your interpretation, bad for you.

The idea of time as a space-like dimension is not so easy to discuss but if you can criticise others you should be able to offer better language.

Or perhaps you are unable to disentangle the issue of the language from that of the logic of it? In which case I don't see how we could constructively discuss your point.
EB