New-Time Travel

[Simon Bridge]

I am guessing that I-95 is a train? If so, you are travelling on and with a train, and with time, in the direction of north. North isn't travelling. Time is travelling from moment to moment.

I-95 could be "Interstate 95" as in "highway" if this is a yank.

You lost grip on your metafore though ... though he's travelling north, that's a direction like forward or backward.

I travel forward in time in that I remember the past (so I'm not travelling backwards) and one thing happens after another (so I'm travelling). However, I am not "time-travelling" forward in time (technical use here) because I cannot pass the present time.

Now, were I to travel in time only, but keep the same reference frame as you, then you would see me stationary for a while. Then I start moving and announce "I time-travelled" here. How would you know the difference?

(Check my watch against yours?)

 

[ynot]

I-95 could be "Interstate 95" as in "highway" if this is a yank.

Thanks - obvious when you think about it. Like you, I live in NZ - you know what it's like.

You lost grip on your metafore though ... though he's travelling north, that's a direction like forward or backward..

Travelling in the direction of north, not with it.

Now, were I to travel in time only, but keep the same reference frame as you, then you would see me stationary for a while. Then I start moving and announce "I time-travelled" here. How would you know the difference?

(Check my watch against yours?)

Nice trick. Can you give a real life demonstration.

 

[Simon Bridge]

For this kind of thing, it might be helpful to think of it in different terms. Don't think of it like "we" are travelling through time. Think instead that the physical processes involved in forming memories work only in the forward direction. In other words, our perception of the passage of time is a result of the state of our brains changing over time, and not a result of anything travelling through time.

Jeremy

Are we having fun yet?

Similarily, we don't travel in space at all, just our memories and bodies change state with our position.

We can get even more metaphysical ... our memories point in the opposite direction as increasing entropy. This is reasonable - to have a memory, one needs a process which is basically one-way. One-way processes are entropic. So all memories must accumulate in the direction of increasing entropy.

Imagine if the Universe were contracting in some "proper" time. Then entropy would decrease with this proper time, and we would "remember" the universe being smaller. That is, we will experience the universe expanding from past to present and we will experience time as flowing from the future (proper) to the past (proper).

Everything would look just the same as now.

(It's an ill wind that blows no minds...)

 

[Simon Bridge]

Jeremy should note that quantum physicists are used to measuring time in meters and astro-physicists are used to measuring distance in years.

 

[ingoa]

I tend to believe quite strongly that time travel will never be possible. The main reasoning I offer for this belief is as follows . . .

A particular moment of time is described by the exact relative positioning of every single part of the universe as it exists at that particular moment of time.

Nothing more convincing that a strong belief without knowledge...

But seriously. Your second sentence makes no sense. What the heck is a 'A particular moment of time' of the universe?

Not to mention the circular logic:
A particular moment of time is described by the exact relative positioning of every single part of the universe as it exists at that particular moment of time.

A is described as B as it exists at A. Hu?

Before starting discussing a paradox, one has to get the initial conditions right.