Time travel via wormholes

[dstebbins]

It is theorized that, if you can travel faster than light, you can go back in time. Some credence is lent to this theory by the fact that an incredibly small amount of time dilation has been detected in high-speed aircraft.

 

Although traveling faster than light by conventional means is impossible, it is theorized that you might could travel "faster than light" by going through wormholes. Scientists like to describe wormholes as, essentially, "holes" in the space time continuum, essentially shortcuts across the universe.

 

However, taking a shortcut does not amount to faster travel. It may result in reduced travel time, but that is due to reduced distance, not increased speed. If I take a shortcut to the grocery store and get there in five minutes whereas I usually get there in ten, I'm still driving at 35mph all the same.

 

But let's give an example on a larger scale. Let's assume that I'm at Point A, already going at a constant 299,000,000m/s (that's an even-steven 299 million meters per second, slightly below lightspeed, so it's possible under Newtonian physics, even if it would require an absurd amount of energy. Also, the "already" portion is so that we can ignore the need to actually reach top speed), and want to get to Point B, which is 299,000,000 meters away. Let's also assume that Points A and B are opposite sides of a planet (e.g. United States and China) that is precisely 299,000,000 meters in diameter, is a perfect sphere, and conveniently has a tunnel drawn down the middle. At my current speed, I could traverse the tunnel in only one second. To go around the planet in only one second, I would have to travel faster than light.

 

Does that mean that I de facto traveled faster than light? No! It just means I took a shortcut!

 

So, can someone explain to me how going through wormholes to take faster-than-light shortcuts across the universe is supposed to enable actual, bona fide time travel?

Edited June 9, 2012 by dstebbins

[Dekan]

It is theorized that, if you can travel faster than light, you can go back in time. Some credence is lent to this theory by the fact that an incredibly small amount of time dilation has been detected in high-speed aircraft.

 

Although traveling faster than light by conventional means is impossible, it is theorized that you might could travel "faster than light" by going through wormholes. Scientists like to describe wormholes as, essentially, "holes" in the space time continuum, essentially shortcuts across the universe.

 

However, taking a shortcut does not amount to faster travel. It may result in reduced travel time, but that is due to reduced distance, not increased speed. If I take a shortcut to the grocery store and get there in five minutes whereas I usually get there in ten, I'm still driving at 35mph all the same.

 

But let's give an example on a larger scale. Let's assume that I'm at Point A, already going at a constant 299,000,000m/s (that's an even-steven 299 million meters per second, slightly below lightspeed, so it's possible under Newtonian physics, even if it would require an absurd amount of energy. Also, the "already" portion is so that we can ignore the need to actually reach top speed), and want to get to Point B, which is 299,000,000 meters away. Let's also assume that Points A and B are opposite sides of a planet (e.g. United States and China) that is precisely 299,000,000 meters in diameter, is a perfect sphere, and conveniently has a tunnel drawn down the middle. At my current speed, I could traverse the tunnel in only one second. To go around the planet in only one second, I would have to travel faster than light.

 

Does that mean that I de facto traveled faster than light? No! It just means I took a shortcut!

 

So, can someone explain to me how going through wormholes to take faster-than-light shortcuts across the universe is supposed to enable actual, bona fide time travel?

 

Good thought-provoking post.

 

Suppose "wormholes" actually exist. That seems an unwarranted assumption - we've no physical evidence of them. But if they did exist, they'd only be "shortcuts" across space. Like in your US/China example. A straight tunnel, or wormhole, from one country to the other. In a direct line, through the inner thickness of the Earth. This would be a shorter distance, than going a longer circular way, half-way round the circumference of the planet's outer surface.

 

That's clear. You'd get to China quicker, so that could be regarded as a kind of speeded-up "Time travel" into the Future. Maybe.

 

Could this ever make "Time travel" into the Past possible though?

 

I mean - does the Past still exist: is there somewhere or other a place, a world of solid objects, where the Past is still happening? (A guy called O'Brien keeps asking me this).

[RichIsnang]

Time dilation can only slow your passage through time, you can slow your passage in time relative to the earth so when you come back, the earth will have undergone more time than you, so in effect you travelled into the future(as far as you and people on the earth are concerned). But you can never travel back in time, events that you have already whitnessed, you cannot see again. Wormholes are 'links' in the space time continuum that allow you to travel to another place regardless of it's distance away instantly, you will not travel back in time. You have to remember that wormholes are 'shortcuts' in the spaceTIME continuum, so you are also travellin through time, you will be 'in the time' of wherever you go. As far as understand it

[Aethelwulf]

 

 

Could this ever make "Time travel" into the Past possible though?

 

I mean - does the Past still exist: is there somewhere or other a place, a world of solid objects, where the Past is still happening? (A guy called O'Brien keeps asking me this).

 

The 64 million dollar question. I'd say, the effects of distortions would not be great enough to cause time travelling into the past - there is also the Chronological Protection theorem. You can cause some wierd effects within the present time frame however... just like when you stick a clock in the basement of a building then put one of the roof, you can measure a very small time delay.

 

But me saying the effects will never cause large ripples is a personal belief - there is absolutely no reason for me to think that other than choice.

[dstebbins]

Time dilation can only slow your passage through time, you can slow your passage in time relative to the earth so when you come back, the earth will have undergone more time than you, so in effect you travelled into the future(as far as you and people on the earth are concerned).

Exactly. Let's say that I'm put in a spacepod orbiting the earth at a rate of only one meter per second slower than lightspeed. I could theoretically arrive in the year 3000AD with only 24 hours passing by aboard my ship (not mathematically sound, but you get my point).

 

Again, some time dilation has been detected in high speed aircraft, so there is a sliver of credence to this theory.

 

But you can never travel back in time, events that you have already whitnessed, you cannot see again.

Well, the theory is that, if you travel precisely at lightspeed, time aboard your ship will stand still. Time travel into any point in the future using the example given earlier in this post would appear instantaneous (though that does beg the question of... how do you know what year you'll end up in, but that's a different question for a different day).

 

By that logic, if you can surpass lightspeed, your progression through time starts to delve into negative numbers, thus resulting in going back in time.

 

The problem is that... it's currently thought to be impossible to travel at or beyond the speed of light. So... what to do?

 

I mean - does the Past still exist: is there somewhere or other a place, a world of solid objects, where the Past is still happening? (A guy called O'Brien keeps asking me this).

 

Well, we do have the "parallel universe" theory to turn to.

Edited June 10, 2012 by dstebbins

[Bill Angel]

Suppose "wormholes" actually exist. That seems an unwarranted assumption - we've no physical evidence of them. But if they did exist, they'd only be "shortcuts" across space.

I think that another issue should be mentioned. Even if wormholes did exist, while matter and energy could enter one end of the wormhole and then exit at some other point in space-time, information would not. Matter would be ripped apart into its most elementary constituents before being spit out of the wormhole's other end. I'm just extrapolating here what is expected to happen to matter when it falls into a black hole. Why would the physics of a wormhole in this regard be any different?

[RichIsnang]

It's a good point bill, people overlook so many things when thinking about wormholes. Firstly, there is no current theory of how wormholes can be created, they theoretically are possible, so to travel through one, you would have to get lucky that it goes to the right place. Secondly, you have to survive travel into and through a black hole, and then out the other side of another one presumably, both of thee problems have many other problems associated with them.

 

Dstebbins, I'm intrigued by your point 'how do you know what year you'll end up in', do you mean as soon as you hit light speed(however you manage it) you will instantly stop your passage through time, so cannot then slow your ship down to drop back into time as you are frozen in time? Or will, in your reference frame, everything seem normal in your ship and everything else goes black? or is it not really worth thinking about because it is impossible?

[Mynameson]

Wormholes are only shortcuts the join point A very close to point B actually that close that u dont need an external force to get accelerated to light-speed. Now the entering of a wormhole is the blackhole which has nearly infinte gravitational pull and that means your body is accelerated directely above lights speed but nothing can pass through a black hole without being turned into "noodles" if u now wht i mean. So basically that's it. But that's just my opinion. PS after getting out of the wormhole u are ejeceted by the white hole at light speed But u may try the string theory if u dont like wormholes they also create shortcuts to go faster from A to B.