For budding time travellers, the future (or should that be the past?) is starting to look bleak. Hypothetical tunnels called wormholes once looked like the best bet for constructing a real time machine. These cosmic shortcuts, which link one point in the Universe to another, are favoured by science fiction writers as a means both of explaining time travel and of circumventing the limitations imposed by the speed of light. The concept of wormholes will be familiar to anyone who has watched the TV programmes Farscape, Stargate SG1 and Star Trek: Deep Space Nine. The opening sequence of the BBC's new Doctor Who series shows the Tardis hurtling through a "vortex" that suspiciously resembles a wormhole - although the Doctor's preferred method of travel is not explained in detail. But the idea of building these so-called traversable wormholes is looking increasingly shaky, according to two new scientific analyses. A common analogy used to visualise these phenomena involves marking two holes at opposite ends of a sheet of paper, to represent distant points in the Universe.

One can then bend the paper over so that the two remote points are positioned on top of each other. If it were possible to contort space-time in this way, a person might step through a wormhole and emerge at a remote time or distant location. The person would pass through a region of the wormhole called the throat, which flares out on either side. According to one idea, a wormhole could be kept open by filling its throat, or the region around it, with an ingredient called exotic matter. This is strange stuff indeed, and explaining it requires scientists to look beyond the laws of classical physics to the world of quantum mechanics. Exotic matter is repelled, rather than attracted, by gravity and is said to have negative energy - meaning it has even less than empty space.

View: Full Article | Source: BBC News

I think there's a lot more we need to learn about space itself before we even really consider time travel.

if it at all is possible...

Time travel is absolutely possible. I have gone a head in time 51 years. One day at a time! Unfortunately going back to the late 70's has proved difficult.

But if you see a long haired, white bearded, toothless, overweight, older man, ask him what he did in High School. He may close his eyes for a second. He may shed a small tear for lost loves and opportunitys missed. But he will take you back to a simpler time, where the problems of the world didn't mater as much. And a life time of love was still some thing to look forward to.

The best time machines in the World are your Grand Parents. Don't wast them.

Grandpa Roger,

Thanks for reminding me a great novel by Ray Bradbury

It is so.

bah, i knew that whole wormhole mumbo jumbo was crap...bahh

I doubt this will stop science fiction authors and directors from using them in their books, television shows and movies anytime soon!

Stargate SG1 never used the worm hole for time travel... they used the Ancient guy's time machine and one of their ships.

Indeed, however what you're saying is true, in fact in the episode 'The Empty Child', Graphically described and showed The Doctor and his Tardis chasing an unidentified object as it jumped between worm holes.

Doctor Who nut

Yea but the fact that we don't have time travelers popping out left, right, and centre should be self explanatory that we will never travel in time.

Nope. They actually had a wormhole pass by a solar flare and that redirected them to 1964 or 74.



Either that or we never make it to tech to do that.

I think one of their ships from the Azgard was named the O'Neil. I loved the eppy 1969.
I'm way off topic here. Actually the Stargate isn't a time machine it only takes them to other places. It was a solar flare that took them back in time. The Stargate isn't a time machine.
If someone already stated this sorry I'm just plain lazy.

I believe the Time Lords have their own black hole, and relay the power to all the tartases by like sub-space. There was an episode about it in the 80's but I don't remember to well. Getting old you know!

Black holes have no problem devouring whole planets.In light of that who is going to volunteer to be the first to step thru.-usdi Agaluga

I don't know about Volunteers, But I got a list of people I would push through!

Did I say that?

and in the episode 2010