Can We Time Travel?

Can We Time Travel? A Theoretical Physicist Provides Some Answer

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The Conversation

• Peter Watson

 

Yes, into the future by traveling at relativistic speeds. There is no evidence, however, that the past actually exists.

 

I really enjoyed the movie Primer. It's on YouTube.

 

YouTube is a sort of time traveling system.
The past lives there as well.
So is my DVD and VHS player.

 

Indeed. And these time travel systems have built-in protection. You can't "wander off the path," scare the butterfly and change the future as you already know it. You won't come back from your YouTube session and find Donald Trump was re-elected in 2020, or something equally horrible.

I have CDs etc. of Blues originally recorded in the 1920s on 78s. To hear people like Blind Lemon Jefferson and Ma Rainey 100 years on is awesome! (They're also on YouTube.)

https://en.wikipedia.org/wiki/Blind_Lemon_Jefferson
https://en.wikipedia.org/wiki/Ma_Rainey

 

Amazing collection you got.
As to past elections for that we have parallel worlds
There Dokakis, Gore, Dole, Hillary, and others are presidents.

 

Spend enough time on YouTube viewing the past and then look up at the clock. Hey, you're in the future!

 

Literally into the future and at or very near the speed of light. Okay, I am not a physicist nor do I play one on TV but if travel back in time is possible, where are the time travelers?

Traveling forward in time faster than someone else does IS possible. Indeed, it's inescapable. Accelerate yourself to relativistic speeds and your clock will move slower than the clocks of those you pass by. But there's no going back.

 

That, by the way, is a pet peeve of mine. In science fiction movies they never seem to take the time changing consequences of light speed travel into account. You can't go warp speed bopping about the galaxy and come back to your origin. YOU might not have aged much but your planet and its star will be long burnt out.

 

In fact, I've never understood Isaac Asimov's willingness to ignore basic physics in his (otherwise very entertaining) seven volume Foundation Trilogy. He KNEW better!

 

Then again, he seemed to have some trouble with basic counting skills too.

 

Star Trek kind of works this out. “Warp speed” is achieved NOT through traveling faster than the speed of light. Instead, the warp drive literally warps space in front of, wrinkling so the ship can travel through its its accordion-like layers in shorter time. It is space that is warped, not the ship traveling faster than the speed of light. (Think of taking a sheet of paper, folding it many times, then driving a pencil through the folds.)

And how do they warp space? With the parabolic antenna on the front of the Enterprise, of course. What a silly question!

 

A long time ago, I watched some show on PBS where time travel was discussed. IIRC, the theory is that if time travel is possible, it's somehow not possible to travel backwards any further than the invention of time travel. So, if time travel is obtained on June 30, 2031, you can't go back to June 29, 2031. There is a reason for this that I cannot remember right now. It depends on the technologies used.

 

So weird that this topic comes up just now.
I just had a very intense experience with this.
Last night I had a very weird dream about my grandmother, grandfather and uncle (their son) who died 12, 13 and 16 years ago.
It felt so real. I could hear noises, the smell, everything.
It's so long ago yet I still dream so vividly about them that it feels like time-traveling.
I think it's because yesterday the topic of life insurances came up during my work.
The human mind is such a strange thing. It can be triggered by small things to an extent that it can throw you back years in the past for a moment.
Not completely related but this reminded me of it.

 

I remember many years ago some researchers who claimed to have had face-to-face meetings with extraterrestrials (not saying I believe it, that's just what they claimed) said that they told them it's not possible. The reasoning they gave was that "there is no past. There is no future. There is only now". This was said to mean that the past existed but since its time had passed it's no more, and that the future doesn't exist until you reach it and after it's gone it becomes the past as well and is then no more.

I dunno. I'm still mad that Alf ended on a cliffhanger.

 

That's exactly wrong if 1) Einstein was right and 2) I'm right about Einstein. The error sci-fi writers make consistently is to act as if there is a single absolute universal time framework. There isn't. Literally no two clocks in space will agree exactly if they are moving relative to each other. Einstein seems to have thought that all time exists at once and what you experience depends upon where you are.

 

The bit about not traveling back before time travel is invented gets a chapter in one of Kip Thorne's books "Black Holes and Time Warps." Thorne says you could create a worm hole and take one portal with you and leave the other at home. Problem is, that's possible if at all only with "exotic" material the like of which we've never seen. Ever. Anywhere.

 

Can it ever! You hit something there. It's like Marcel Proust's "madeleines" - those cookies that brought back his memories. I find that effect had increased in both frequency and intensity as I''ve gotten older. Some little thing can send me back 40-50-60 years or more and yes - it's like time travel -- I'm THERE.

Happens to me dreaming or can be triggered by whatever, when I'm awake. I've always been a vivid dreamer - and usually remember dreams - sometimes for years. Some are beautiful. Some are very upsetting. I'll take 'em all - gladly. I believe they teach me things.

I think sometimes that we all have internal / internalized knowledge that would fill universities -- but it's difficult to access.