Do you believe that time travel is possible?

[DrPizza]

JLGatsby
1. I don't think you understand, particularly the concept of the two clocks.
Suppose I wear a watch (that has the date) and there WAS a time machine. Now, when I get into the time machine, it takes 3 minutes to get to 100 years from now. When I arrive at 100 years from now, you seem to be arguing that I didn't travel in time, but my watch is off?? "The clocks are simply off, but they both still exist in the present time. One clock is not 'in the future.'" Rethink that statement. It's mind boggling at first.

2. Travelling forward in time is obviously theoretically possible. Travelling backwards in time is a different issue, and relates to the question of someone not killing off Hitler, etc. However,
a) who's to say that there were no positive consequences of Hitler's actions. I mean, without Hitler, what if there were a different chain of events leading to a 2nd World War *AFTER* the development of nuclear weapons?
b) One of the methods which would theoretically allow time travel backwards in time does not allow for time travel to before the device was invented.

3. "infinite past" for the universe is treading thin ice. The Big Bang theory states that space time *began* at the moment of the big bang. There wasn't necessarily a "before". Thus, if the present age of the universe is 15 billion years, there is no such thing as 16 billion years ago.

 

[Rubycon]

Originally posted by: DrPizza
Who says you can't travel 100 light years in 1 second? Isn't 100 light years the distance light travels in one year in the Earth's frame of reference? So, if we have that distance, then something traveling very close to the speed of light (I attempted to calculate how close, but had rounding errors on my calculator) could travel that distance in 1 second, relative to them, which would be 100 years, relative to the earth.


Anyway, perhaps this explanation might help. (although it's not perfect, scientifically)
The speed of light is exactly 299,792,458 meters per second (by definition)

Now, for a moment, imagine you're in the concorde airliner, capable of supersonic flight (faster than the speed of sound). While the jet is traveling faster than the speed of sound, the person 2 rows behind you yells "omg! There's a fire in the engine!" Does the sound reach you and cause you to panic with the rest of the passengers? Yes. That's because the medium through which the sound is travelling from passenger B to you is stationary with respect to you and that passenger (this is a horrible analogy at this point, but it might work.)

Now, since the concorde has been banned, and after it lands safely with that bad engine, aliens come to earth and replace the engines with something making the jet capable of flying at nearly the speed of light (with respect to the earth) The speed of light, again, is 299,792,458 m/s. The jet is capable of traveling at 299,792,457.9 m/s. Again, the guy two rows behind you starts yelling, but he says something more like "holy ******, did you see that alien pass us? That guy is a maniac." Again, it should seem plausible to you that you're going to hear him almost immediately. And, you see his mouth moving while you hear him talking. Then, he pulls out a green pen laser from his pocket, shines it toward you, where it just misses your head, goes into the cockpit and out through the windshield.

If you've followed along so far, you need to stop and think about this: when that laser passes through windshield, it's actually going to be going slightly faster (light travels faster in the vacuum of space than it does in air.) Suddenly, the spaceship crashes into an interplanetary chicken. Frozen of course due to the extremely low temperatures, and it goes through the windshield, releasing all of the air from inside the space ship. Now, the passenger 2 rows behind you blinks out "S O S" in morse code during his dying seconds. Of course, the light is now traveling at c inside your spaceship, no longer going *slightly* slower due to the index of refraction of air.

Did I mention that the aliens put giant headlights on the jet? Now, as those flashes of green light go forward, relative you to, they are traveling forward at the speed of light. Just about this time the space ship is going by the earth.
Does an observer on earth see the light traveling forward at nearly twice the speed of light? Can't happen.
But, how can an observer on earth see the light coming from your ship and moving at the speed of light, if your ship is moving at the speed of light? There's only one way possible: the rate of change of time is different for you on the ship than it is for us on earth.
Einstein's idea was that the speed of light was a constant, rather than the speed of time.

That's like the age old query "If my Ferarri is traveling at the speed of light and I turn on my headlights, what happens?"

BTW we all know what happens if you shine a green laser through a cockpit. Just make sure you're drunk so the beatings won't feel so bad.

 

[BurnItDwn]

Drink 1 bottle of whisky as fast as you can. TIME TRAVEL ... Wake up in an unknown location missing pants.

Time travel happens, it just has side effects. (pants are missing, and also headache, and vomiting)

 

[JLGatsby]

Originally posted by: DrPizza
JLGatsby
1. I don't think you understand, particularly the concept of the two clocks.
Suppose I wear a watch (that has the date) and there WAS a time machine. Now, when I get into the time machine, it takes 3 minutes to get to 100 years from now. When I arrive at 100 years from now, you seem to be arguing that I didn't travel in time, but my watch is off?? "The clocks are simply off, but they both still exist in the present time. One clock is not 'in the future.'" Rethink that statement. It's mind boggling at first.

2. Travelling forward in time is obviously theoretically possible. Travelling backwards in time is a different issue, and relates to the question of someone not killing off Hitler, etc. However,
a) who's to say that there were no positive consequences of Hitler's actions. I mean, without Hitler, what if there were a different chain of events leading to a 2nd World War *AFTER* the development of nuclear weapons?
b) One of the methods which would theoretically allow time travel backwards in time does not allow for time travel to before the device was invented.

3. "infinite past" for the universe is treading thin ice. The Big Bang theory states that space time *began* at the moment of the big bang. There wasn't necessarily a "before". Thus, if the present age of the universe is 15 billion years, there is no such thing as 16 billion years ago.

1. Your watch would be off because it exists in the condition of the day you were in originally, but you still traveled in time. The clock study is implying that the airplane WAS the time machine because the speed increased the time, but in the end, neither of the clocks existed in different times. "Time Travel" is taking a bit of matter and placing it in a different place in time.

Example: Taking something that existed in it's 2005 condition and placing it in 1920 (in it's 2005 condition), or forward in time, 2015 in it's 2005 condition.

2. Traveling into the future is not possible, at all, simply by the fact that the future does not exist yet.

3. The Big Bang does not state when universe itself began, it states when the objects (stars, galaxies, etc) took formation. The Big Bang was a burst of energy when everything existed in one mass. One day everything will exist in one mass again (the Big Crunch). This is how I understand the theory. I believe the universe is a never ending cycle of Big Bangs and Big Crunches. The universe itself has no beginning, only the objects within it.

 

[dexvx]

Originally posted by: JLGatsby
Also, if time travel will one day be possible, why hasn't someone gotten rid of all the problems of the past?

Why didn't anyone kill Hilter before he committed his crimes?

Why didn't anyone travel to 1930 and tell the Federal Reserve to quit raising interest rates during a bad economy, which helped cause the Great Depression?

Why didn't anyone travel back to the time of Jesus to meet him and see if he was a hoax or not?

Why hasn't a time traveler appeared before us and gave us the technology to rid the world of disease and hunger?

There are three options which would anwer these...

1.) Humans will not exist long enough on this Earth to invent time travel, even though it is possible.

2.) Parrellel dimensions exist and time travelers have traveled/created parralell dimensions where these problems are fixed.

3.) Time travel is not possible.

Take your pick.

Oooh... temporal ethics come into play. Lets assume time travel in the past is possible and it *will* change the future. Why would people not do any of the above good deeds? Simple answer... it will irrefutably change history, for the better or worse.

Simple example I'll bring up is Hitler:

If there was no Hitler, then a lot of "good" things won't happen. Technological advances from World War II, such as the jet, rocket, nuclear fission or conceptuals such as world peace, facism (and how to prevent it) will never happen. But lets be REALLY abstract...

Suppose that post-WWII, an American GI met some girl in France and got married and had children. The children have children, and so on. Suppose that generations down the line in that family, a person is a key researcher that had a significant role in inventing the next big thing (I dunno? Anti-matter reactor? Warp drive?). By killing Hitler and thus changing World War II's timeline, that couple would NEVER have met and thus you just killed off one of your great future scientist.

The point is, changing details in history has an incalculable amount of consequences that are impossible to predict. The longer you travel back in time and change things, the worse it gets... the Complexity is just astronomical (for you Math/Comp-Sci students).

 

[dexvx]

Moreover, assuming someone did go back in time and change some random events, we would not know. To us, relatively, this timeline is "normal". It would be literally impossible for us to tell the difference between a timeline that is "tampered" and one that has not been "tampered" with... (insert conspiracy theory here).

But back to the OP's question:

Atomic clocks placed on probes and shuttles have indicated a slight differential in time. If you know how atomic clocks work, then you would know that it is indeed true that time is relative. The closest thing to traveling to the future would be getting on a vehicle that can sustain near light-speed (say .995c), traveling to Alpha Centauri and back. About 9 years would pass for you while (ok I'm gonna be lazy on this) a few hundred hears will have passed for the rest of humanity.

 

[HBalzer]

Originally posted by: Legend
Forward, I'm betting is possible. Backwards, I'm not so sure about.


We really don't know a lot to really say what we can or cannot do. Relativity and Einstein are like our time's Greek Philosophers talking about our solar system.

I am traveling into the future as we speak soon I will be in tomorrow.

 

[Vic]

Originally posted by: cshel
I hope so, cause I want to live in the 70's!

I already did. It sucked.


To everyone: the OP specifically said non-relativistic time travel. Non-Einsteinian.

"Say I have some machine that can take me 100 light years in 1 second. When I reach my destination, I have aged 1 second. So have the people on earth. If I come back in 1 second, I'll have been gone for 2 seconds total, and both me and the people on earth have aged 2 seconds."

It's not possible.

 

[DaShen]

Possible, yes. Will humankind ever reach a point where they will be able to do it No.

 

[JLGatsby]

Originally posted by: dexvx

Atomic clocks placed on probes and shuttles have indicated a slight differential in time. If you know how atomic clocks work, then you would know that it is indeed true that time is relative. The closest thing to traveling to the future would be getting on a vehicle that can sustain near light-speed (say .995c), traveling to Alpha Centauri and back. About 9 years would pass for you while (ok I'm gonna be lazy on this) a few hundred hears will have passed for the rest of humanity.

You need to ask yourself, is it a "slight difference in time" or is the speed simply having an effect on the clocks?

If these two clocks have different times, does that mean one exists in a different time than the other? Did time really slow down with one? Or more likely, did the speed cause the clock to slow down? Does high speed slow time or slow atoms?

If not, how does this study support time travel?

 

[LeiZaK]

Everyone knows all you need to travel time is a 1986 Ford Taurus...

edit: I don't feel like getting into a serious discussion on the subject even though I know the truth... Just seems like beating a dead horse at this point. Some people fail to see the undeniable truth even when it is right in front of them.

Time travel into the future is very possible. Time travel to the past is not (at least through any currently existing conventions).

Time is an illusion.

I won't explain myself further in accordance to the above statement.

 

[Kenazo]

I would say no. We'd be overrun by time tourists otherwise...

 

[RaDragon]

Originally posted by: GagHalfrunt
Geesh, this must be a repost, I already answered this question next week.

You sure you didn't go back in time?

 

[JLGatsby]

Originally posted by: Kenazo
I would say no. We'd be overrun by time tourists otherwise...

Time travel can still exist and we would not experience or be effected by it.

Two of my three explanations:

1.) Humans will not exist long enough on this Earth to invent time travel, even though it is possible.

2.) Parrellel dimensions exist and time travelers have traveled/created parralell dimensions where these problems are fixed.

The second one dictates that you cannot travel backward in the same dimension. A dimension simply exists either for every possibility (infinite dimensions) or a new one is created with each time travel.

 

[dexvx]

Originally posted by: JLGatsby
You need to ask yourself, is it a "slight difference in time" or is the speed simply having an effect on the clocks?

If these two clocks have different times, does that mean one exists in a different time than the other? Did time really slow down with one? Or more likely, did the speed cause the clock to slow down? Does high speed slow time or slow atoms?

If not, how does this study support time travel?

The way atomic clocks work:

http://en.wikipedia.org/wiki/Atomic_clock

Translation/Induction: Since the matter is "slowing" down at the atomic level, one would assume that ALL atomic entities encapsulated within that space-time is also "slowing" down. Now how do you test that hypothesis? Scientists can accelerate sub-atomic particles close to the speed of light in mass drivers. Muons that take micro-seconds to decay can have their life expectancy increased several hundred fold. In theory, that should hold true for larger atomic structures (eg humans) as well.

Practical Theory: If you orbit the Earth at near critical velocity for 1 year, in actuality all the atoms in your space-time has been "slowed" down. So while 1 year has passed for you, 10 years (or more) may have passed for people on Earth. Unless you think the entire Earth is playing some kind of practical joke on you, that would be the ultimate proof of relativity. Unfortunately, it is impossible with today's technology.