Wormholes and time travel

[Brian G Turner]

Okay, here's a link to a ercent article in Nature magazine about Wormholes - everyone's favourite* method of Time Travel.

Making a wormhole just got easier...but it's no simple matter.

*meaning most scientifically plausably practical.


So, to open up the discussion - Time Travel - possible or not?

If there is Time Travel then obviously none of us can go back in time and alter the past. Or could we? OR would the future then be part of the past and thus not negatable?

Is time even linear (past, present, future)?

Or wuold Time Travel actually never achieve more than travel into infinite possible universes where the past is like our own, only the future has not occurred - and if so, how would you know?

Or is Time Travel itself not even remotely likely in any of the above scenarios?


Comments, if you will. ;D

 

[nemesis]

If time travel were possible we would have met the future by now. The ability for humanity to invent time travel as fiction would have us believe is disproven by the conspicuous absence of time travellers.

 

[X Q mano]

"Time-travelling" forward wouldn't be impossible I think, but back again? Hmmm...

I suppose, if you could make a ship travelling at far above light-speed or something, then time would be different for the occupants on that ship compared to earth. But back again, that would be a problem methinks...

And there are people who claim to be time-travellers... But more often than not we lock them up in rooms with padded walls...

 

[Brian G Turner]

I like the idea that if time0travel were possible, it has alerady been accounted for by time, and hence the time travellers are here but are unable to change the past because the past always involved them and they were always unable to change whatever it was they wanted to change!

 

[nightwalker]

It can't be done. If it could there would be no future to create time travel because there would always be someone changing the timeline. People could time travel to prevent the time machine being built and so create a parado,,,,I think.

 

[X Q mano]

Anyone read Hitchhiker's guide to the galaxy series?

There you are presented with an interesting problem when it comes to time-travel... i think it's in the Restaurant at the end of the universe book...

 

[Brian G Turner]

Saw the BBC TV series but remember little of it, other than as a kid I just didn't "get it".

Would you care to enlighten as to the restaurant at the end of the universe issue? Intrigued.

 

[X Q mano]

I would have to grab my book at home... I'll see if I can do it tomorrow ok? It's really funny...

 

[X Q mano]

Ok, here goes... This is a quote from the book "The Restaurant at the end of the Universe" by Douglas Adams. If I'm doing something illegal here, I apologize. It's a really great book and a great trilogy (of five books) and it is highly recommended.

ONe of the major problems encountered in time travel is not that of accidentally becoming your own father or mother. There is no problem involved in becoming your own father or mother that a broadminded and well adjusted family can't cope with. There is also no problem about changing the course of history - the course of history does not change because it all fits together like a jigsaw. All the important changes have happened before the things they were supposed to change and it all sorts itself out in the end.

The major problem is quite simply one of gramma, and the main work to consult in this matter is Dr Dan Streetmentioner's Time Traveller's Handbook of 1001 Tense Formations. It will tell you for instance how to describe something that was about to happen to you in the past before you avoided it by time-jumping two days in order to avoid it. The event will be described differently according to whether you are talking about it from the standpoint of your own natural time, from a time in the further future, or a time in the further past and is further complicated by the possibility of conducting conversations whilst you are actually travelling from one time to another with the intention of becoming your own mother or father.

Most readers get as far as the Future Semi-Conditionally Modified Subinverted Plagal Past Subjunctive Intentional before giving up: And in fact in later editions of the book all the pages beyond this point have been left blank to save on printing costs.

 

[Brian G Turner]

That's actually pretty good.

 

[dwndrgn]

The Guide is hilarious! I recommend it to anyone who just needs a chuckle to make a bad day better. ;D

As for time travel...well, I'd like to believe it but it just doesn't fit into my own personal form of logic. Just the fact that time itself is an idea, not a fixed thing sort of makes the logistics a little weird. My brain is wiggling just trying to think about it.

I find the idea of *place* travel much more plausible - that there are parallel universes/realities that could be *jumped* to, as depicted often in fantasy novels. I couldn't really tell you why this seems more plausible ??? Maybe I am just more fascinated by it so want to believe it.

 

[Brian G Turner]

Would anybody actually want to go back in time and intentionally change the past?

 

[X Q mano]

It would be tempting sometimes... But I have made up my mind to never regret anything... So I would try not to change anything either...

 

[Brian G Turner]

Ah - but what about regretting what happens to other people, though? For example, I figure a lot of people would want to prevent the implementation of "the Final Solution" the Nazis. However, wouldn't stopping that have an inadvert negative impact? In the realm of genetics that we currently explore, the whole issue of Eugenics has been thoroughly destroyed precisely because of the Nazis. However, before them it was an entirely respectable field. Without Hitler, we could be stumbling into a whole different Eugenics nightmare right now - and with far, far, more powerful tools.

 

[Arch]

I would go back in time, collect some items I know are rare in the present day, and then bury them. Then I would return to the future to where I buried those things and then unbury them! Hence I become rich and the world and is enriched by my new discovery!

 

[littlemissattitude]

May I recommend Kage Baker's series of novels about an entity called the Company, which will, in a couple of hundred years or so, invent both time travel and immortality? She has some interesting takes on how time travel could work and how to avoid paradoxes. The books are: In the Garden of Iden, Sky Coyote, Mendoza in Hollywood, and The Graveyard Game. There is also a collection of loosely related short stories, the title of which I cannot recall offhand.

Oh, and also David Gerrold's The Man Who Folded Himself. This is a quick read from the man who gave us Tribbles, which postulates that wherever a paradox might logically occur during time travel (as, when we meet ourselves), another time thread or alternate universe opens up. It has been a long time since I read this one, but as I recall it was a fairly entertaining book.

For another take on time travel, one which is in a very real way much more pessimistic about its effect on the world, try Pastwatch: The Redemption of Christopher Columbus, by Orson Scott Card.

As far as the possible reality or possibility of time travel goes: I don't the know the physics involved, so I can't comment on it on that level.

I just know that I love time travel stories, and some part of me hopes that it is possible. I think it is the historian in me, who would love to be able to witness past events to see what really happened, as opposed to the interpretations of those events that have come down to us.

By the way, is there anyone here old enough to remember the old television series, "The Time Tunnel"? It was quite cartoonish, but lots of fun at a time when we really didn't have much science fiction on television.

 

[Brian G Turner]

Ah - now, we're really into multiverse theory there! Used to be a favourite of mine (now I simply don't think about it - or am simply not sure what to think).

Anyway, here is the website of David Deutsche, who is the effective progenitor of multiverse theory:

 

[dwndrgn]

I loved the Kage Baker books. Wish there were more. I love time travel stories as well - but usually only if they go backwards through time instead of forward.

Very nicely done - lots of thinking involved, good character develpment and wonderful historical scenes.

 

[Brian G Turner]

Just found something else about Wormholes from the Ne Scientist website:

Quantum wormholes could carry people

All around us are tiny doors that lead to the rest of the Universe. Predicted by Einstein's equations, these quantum wormholes offer a faster-than-light short cut to the rest of the cosmos - at least in principle. Now physicists believe they could open these doors wide enough to allow someone to travel through.

Quantum wormholes are thought to be much smaller than even protons and electrons, and until now no one has modelled what happens when something passes through one. So Sean Hayward at Ewha Womans University in Korea and Hisa-aki Shinkai at the Riken Institute of Physical and Chemical Research in Japan decided to do the sums.

They have found that any matter travelling through adds positive energy to the wormhole. That unexpectedly collapses it into a black hole, a supermassive region with a gravitational pull so strong not even light can escape.

But there's a way to stop any would-be traveller being crushed into oblivion. And it lies with a strange energy field nicknamed "ghost radiation". Predicted by quantum theory, ghost radiation is a negative energy field that dampens normal positive energy. Similar effects have been shown experimentally to exist.

Delicate balance

Ghost radiation could therefore be used to offset the positive energy of the travelling matter, the researchers have found. Add just the right amount and it should be possible to prevent the wormhole collapsing - a lot more and the wormhole could be widened just enough for someone to pass through.

It would be a delicate operation, however. Add too much negative energy, the scientists discovered, and the wormhole will briefly explode into a new universe that expands at the speed of light, much as astrophysicists say ours did immediately after the big bang.

For now, such space travel remains in the realm of thought experiments. The CERN Large Hadron Collider in Switzerland is expected to generate one mini-black hole per second, a potential source of wormholes through which physicists could try to send quantum-sized particles.

But sending a person would be another thing. To keep the wormhole open wide enough would take a negative field equivalent to the energy that would be liberated by converting the mass of Jupiter.

 

[GnomeoftheWest]

I would go back in time and become an oracle.

(and write the Beatles' "Yesterday" myself)