History
I try not to talk about these things too often, but Stephen Hawking, speaking loosely and probably after knocking back one-too-many, has publicly suggested the possibility of time travel. He reaffirms that travel into the past is impossible, so there's no need to quibble on that point. However, he posits the potential to travel forward, relying on Einstein's theory that objects nearing the speed of light progress through time at a "relatively" slower rate than objects on Earth. That is, a person moving at 98% of the speed of light for 20 years would find the Earth had "aged" 7,500 years.
Yet this is not due to a traveler having stepped outside a "stream" of time and reinserting himself in an extant, "future" age already in place and waiting to be discovered. Rather, in accordance with static theories of time as a non-progressive measurement of "aging," it simply reveals the unified application of time's effect on various objects in a consistent manner, according to their relative conditions (i.e., speed). So, there is no future world (or infinite worlds) already in place, merely awaiting our arrival. Time is simply the observation of material entropy and the extinction of potential possibilities (i.e., thoughts and actions) through the free-willed choice of particular decisions during a single, ever-present moment.
Steve is so sloppy about these things sometimes.
I think he just caught planet of the apes on cable.
Time travel? I got yer time travel right here.
Plus, for non-scientists, the possibility of future time travel is cool because it allows you to see what the future holds for you. Well, if you're sitting on a damn train for 7500 years, nothing really happens to you, except your house gets foreclosed upon. Now, granted, it would be pretty cool to see how things turn out in 7500 years, but you'll never really know if that girl from 7th grade liked you, or liked you liked you.
This isn't particulary new, either conceptually or practically. Gott discussed both time dilation as well as the possibility of travelling backwards over a decade ago in Time Travel in Einstein's Universe.
https://en.wikipedia.org/wiki/J._Richard_Gott
Tom
Well, I'll give Dr. Hawking half-credit because technically we all are traveling through time, or time is travelling through us, or both. Anyway, Brutus is right. Chuck Heston has already been down this road. Statue of Liberty, talking primates, Dr. Zeus! Dr. Zeus!. Doc-tor Zeus! (sung to Rock me Amadeus) etc.
Mr. Paulette,
You're knocking down a straw man, and it's hard even to figure out what your straw man consists of. Neither Hawking nor any physicist that I've ever heard of claims that traveling into the future by means of time dilation involves "stepping outside a 'stream' of time, and reinserting himself in an extant, 'future' age already in place and waiting to be discovered." If you want to be understood, you should say what you think Einstein's time dilation does involve or imply.
Tom Trumpinski,
It goes back a whole lot further than Gott. Einstein's time dilation was popularized certainly no later than the 1950s (I knew about it as a teenager), and I wouldn't be surprised to learn that it was popularized in the 1920s or even earlier. Moreover, the space travelers example was practically the only example the popular books ever used.
This is pretty funny.
Two analogies, related.
First analogy. Two computers. The first has a 500 MHz clock speed. The second has a 1.5 GhZ. To the computers, one billion calculations is one billion calculations done in one billion operations, no more, no less. To us on the outside, there is a substantial difference--time.
Second analogy. One tire or flywheel, two different RPMs. But only one power input--the same at both speeds. Thus two different torques, and two different accelerations.
Wow! That dude Hawking must have gotten hold of a Heinlein novel from the 1950's.
In a sense he's proven that travel into the past is possible even as he denies it's possibility. Talk about a paradox.
The author of another blog site used the application of the Lorentz transformations and E=mc sq. to explain a problem with the amount of energy required to put a spaceship of any mass near the speed of light.
According to my physics professor, Hawkings is not considered the best physicist, but the most famous.