eBay in sensational Back to the Future coupon deal

Of course...

...the best thing to do is to buy the time machine itself from eBay, using a coupon in 1970, then when you're done with it, take it back to 1970 and list it on eBay so that it can be used as something to buy with the coupon. Otherwise there won't be anything to buy.

P.S DON'T forget to take it back. I mean, really, don't.

Epochalypse now!

Hey, I just invented a catchy new term to describe the y2038 bug when it rolls around!

<dons sandwich board> Beware, unbelievers! The Epochalypse is coming!

Time travel

One interesting idea I read a long time ago in a sci-fi book far far away, was that we can posit 100% that (backwards) time travel does not exist, and will never exist by the hypothesis;

Should time travel be discovered, it will be used.

Should it be used, its users will make mistakes and leak information about it's existence how it is done to the travelled-to time.

Given the infinite nature of time, the probability of those leaks (via the users) will approach 1. Also, all times will be vistied an infinite number of times.

Given the above, the fact that we haven't heard about real time travel now means that it does not exist in any future, no matter how much time passes.

QED, time travel is impossible.

Backwards Time travel is possible

Angus Wood is correct in everything he postulates, but has forgotten that every time a decision is made all possible results are played out (the cat is alive/dead/dying etc). It just so happens that we are in the time stream that has no time travel discoveries in it, and has not been visited. If we jump to another reality, then we will see all those other us's talking with time travelers.

OR

The ghosts that people see are really time travelers (they are round us all the time, we just can't see them), but they can only observe and not interact with anything or anyone - some sort of natural time law prevents this, you cannae change the laws of quantum physics Jim!

OR

Some other badly researched, scientifically flakey, made up during a meeting with the green fairy, idea that has no possible chance of being true - but could form the basis of a movie.

Science Lesson...

It is possible that ebay exists in 1970 due to them travelling back in time from some point in *our* future. By changing time in 1970 the timeline will skew to form an alternate 1970+ (shall we call it 1970A), thereby leaving our timeline with a dissapeared ebay time team.

Now comes the hard part. With the timeteam jumping realities, so to speak, there exists an entropy imbalance against our side. This explains the appearance of said coupon in our time, as the confusion it is causing with el reg readers is helping address the imbalance of life without the timeteam.

Finally we need to consider when said timeteam will actually attempt the jump. My theory predicts that the jump should take place a few hours before the epochalypse (copyleft DaveK). I reach this conclusion based on the availability of power sources for flux capacitors. The UK and US will have enough nuclear plants by then to ensure a steady supply of plutonium tat being listed.

For further information please see Back to the future part II and Stargate SG1 (available from any good encrypted torrent merchant), UK.gov (various pages listing nuclear ambition) and ebay.co.uk (for tat, flux technology and U-238)

Erm, yes, black with a silver zip. No i don't want the white one with the pretty wraparound sleeves.

@DaveK

Great Minds/Fools etc.

http://epochalypse.com/

@Angus Wood

> Also, all times will be vistied an infinite number of times.

"Vistied" (past tense) - From the verb "to Vista", meaning, "to install a malfunctioning and technically deficient mess of an operating system on a computer, in order to damage the mental health of all users of said computer and in order to render it completely unusable."

Pish!

This is nothing!

SkyNet, the computer intelligence that Google will inevitably grow into, has done loads of stuff with time travel...

Well... not yet... but it will do!

@Angus Wood

Some of the more plausible time travel theories suggest that you can only travel back as far as the time from which you started, thus your argument doesn't necessarily hold.

It's entirely possible that in the future, time travel will be attempted (e.g. by dragging one end of a wormhole at relativistic speeds around the sun and back) and we'll immediately know if it works because the test subject will instantly arrive back at our time.

Of course, we should really consider spacetime rather than thinking of time and space being separate.

Anyway, we are all already travelling in time, just forwards, at the same speed (nearly) as everything else around us. So we are all time travellers!

The first time machine builder...

Had better test it in a large, open area!

The last theory I read said that if you build a time machine, you can't travel any further back than the first time it's first turned on. So... the best test that a time machine works is that someone from the future pops out of it to witness the first time machine being activated.

Of course, thousands, possibly millions of time travelers will want to witness such an historic event, so there will be a flood of people popping out of it to witness it's creation.

I'd recommend plenty of restroom facilities and a good caterer!

On another note:

Say Bob has built a time machine, but keeps it locked for security reasons.

Jim wants to use it and asks Bob for the key.

Bob: "Ok, but I have an experiment ready to go in two minutes."

Jim: "No problem, I'll come back before I leave!"

So, just as Bob reaches for his pocket to get the key, Jim pops out of the machine, back from his trip, and tosses the key to The Jim that hasn't left yet, who then enters the machine and leaves. (You still with me?)

Now here's the question: If Bob reaches into his pocket, is the key still there?

@Wilco

> http://epochalypse.com/

Hey, thanks for the link, I guess it was fairly obvious after all.

What's really brilliantly beautifully poetically ironic about it is that when I surf to that address, all I see is a web page announcing:

Epochalypse Countdown: 00 years 0 months 0 weeks 0 days 00:00:00:000

;-)

[yeh, I know it's only because of noscript really...]

Time Travel Sense

Please read "By His Bootstraps" by Heinlein BEFORE posting any sci-fi-based time travel mumbo-jumbo.

@Angus Wood

You miss the small point that if you cannot travel back in time to before Time Travel was invented, it just means that, at some time in the future, someone will say "hang on a minute, how did they invent Time Travel in 2009 when the technology wasn't available", jump back in time to see how it was done, then find that, of course, the technology wasn't available, so they have to invent it in order to make their trip possible in the first place...

Proof of Time Travel on eBay!

A Ford Focus from 1899- 4 years before the Ford Motor Company was even created!

http://cgi.ebay.co.uk/1899-Ford-Focus-LX-1-8TD-MANUAL-5-doors-Hatchback_W0QQitemZ280185111600QQihZ018QQcategoryZ9844QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Shame it's not a DeLorean, really...

And Captain Daft, yes the key would still be there. Future Jim gave his key to Present Jim, who then became Future Jim and gave his key... and so forth back to the initial and highly controversial creation of the universe. Bob's key isn't interacted with.

The real conundrum is what would happen after a few trillion loops for this poor key- what if it wore out and couldn't unlock the time machine door anymore? If the loop stopped, the key wouldn't exist or would at least not be damaged. And there'd be 2 Jims in the world.

@ DaveK

Epochalypse Countdown: 30 years 2 months 1 weeks 3 days 23:25:19:979

The other thing about time travel

If time travel is invented and all the problems with being the father of your grandfather etc apply then...

...time will no longer be a matter of past, present and future in straight lines and we will need to think in terms of numbers of dimensions rather than one line.

Hollywood's version

I think it's funny how Hollywood's version of a "Time Machine" does not involve any real thought. Let's all for a moment ignore the fact that time and space are indeed connected and that you can't make a time machine out of ordinary household goods (minus the radioactive bits stolen from the commies). Let's say I jump in my shinny new time machine and go back 50 years. Hollywood's version of a Time Machine is convenient in that they not only control time, but can move me through vast distances too! 50 years ago, the Universe, Galaxy, Solar System, Planet, Continent, and soil have all moved from there present locations... we are in a constant state of motion! If I jumped back 50 years... I most likely would be in a void of space FAR from where I started... so much for that. I would spend all of my time trying to figure out where the hell I am, the crazy thing is... that is the easiest problem to overcome. It makes for nice Sci-Fi though.

@Ben Cross

Thanks for that, but I missed you posting - what time does it say *now*?

@Steven Knox

and then David Gerrold took the concept to the logical conclusion in "The Man Who Folded Himself", considered by many to be the quintessential time travel tale.

The same David Gerrold, by the way, who took Heinlein's Martian Flat Cats and turned them into the Star Trek episode "The Trouble With Tribbles".