Where are all the time travellers?

[avevale_intelligencer]

Somebody asked this question (rhetorically, of course) on a documentary we watched a while ago, and on the face of it, it's a good one. If time travel is possible, why haven't we been surrounded by quaintly-dressed strangers with futuristic camera phones snapping pictures of the London Eye before it blows up in 2011, pinching priceless art treasures before they get destroyed, or trying to fathom why supposedly intelligent people would ever elect Margaret Thatcher, John Major and Tony Blair?

Answer is simple, if you go with the theory of time travel as propounded by eminent crank and sf author James P Hogan in The Proteus Operation, which sadly seems to me to be the most plausible. Forget about the notion of new timelines sprouting off whenever someone chooses to have toast instead of cereal for breakfast; much too cumbersome. For the most part, the universe lumbers on along a single timeline, not predestined but going the way of the choices that people actually make, unless someone arrives in it from a different point in time. At that moment, a new alternate timeline is created, and the time traveller inhabits that timeline, not ours. If he's travelled back in time, it branches off from his arrival point; if he's gone forward, he goes to the future as seen from where he is, which is not the future the main line is heading for. (Example: someone going forward from here would travel to a world where global warming has wrecked the climate, while on the main line Professor Dinkelfwat's amazing discovery of greenhouse-gas-eating nanobots in 2014 will save us in the nick of time. I hope.) Either way, while these timelines are just as "real" as the main one by any criteria that the traveller can apply, they're not the main one. The one thing you can't do with this kind of time travel is go home.

Of course, this theory of time travel is extremely depressing and of limited use for stories, like most real-world science these days. But it seems plausible to me, and answers the rhetorical question above.

Comments

[filklore-on-lj.livejournal.com]

Then again, it might go more like this:

http://xkcd.com/716/

[zanda-myrande.livejournal.com]

Mmm. Not everyone would do that. It would only take one.

[legoline.livejournal.com]

If time travel is possible, why haven't we been surrounded by quaintly-dressed strangers with futuristic camera phones snapping pictures of the London Eye before it blows up in 2011, pinching priceless art treasures before they get destroyed

You know, I have never thought about it like that but it's a very valid point.

[redaxe.livejournal.com]

Haven't read that Hogan, but it sounds like he might have been inspired by Alfred Bester's The Men Who Murdered Mohammed. Either way, time travelers in their "own" worlds could work.

I subscribe more to the theory (as showin in, e.g., Connie Willis' The Doomsday Book), that time travelers are prepared with authentic-appearing clothing, et al.

Assuming, of course, the extreme unlikelihood of time travelers. (FTL seems orders of magnitude easier, scientifically, than time travel.)

[billroper]

I prefer Poul Anderson's Time Patrol, where a dedicated group is busily preventing others from messing up the time stream.

[keristor.livejournal.com]

The "fork[1] if it changes things"[2] theory is one way of solving it, and by Occam's Razor it seems to me to be the simplest. But there are others, such as only closed loops being viable (i.e. the time traveller created the world from which they came because they came, like in Spock Saves The Wales where Scotty tells the secret of transparent Aluminum to the person who 'invented' it).

[1] "Fork it!" he said...

[2] I don't think it's needed for going to the future. Probably in our past no one has invented one yet, and when one is invented and someone goes forward that may cause comment then but we still don't know about it yet.

[vixyish.livejournal.com]

Here's a joke for you!

"Time traveler!"
"What?"
"Knock knock!"

:D

(I forget where I saw that, but I didn't make it up, so I can't take credit.)

[howeird]

I don't see why the time traveler couldn't go home to the main timeline any time he/she/it wanted to. It is separate from the branches, the time traveler's travels would have no effect on it.

[armb.livejournal.com]

In some models, a time machine only allows travel back to the point where it was first built e.g. http://en.wikipedia.org/wiki/Tipler_cylinder
(Ignoring the "it does actually have to be infinite in length to work, you can't just assume an infinite length to simplify the maths and hope that a long enough approximation will work" detail....)