LAT: It's official: Time machines won't work

[Larry]

From the LA Times Business section . . .


Doc's super fast car won't do it. Neither will Bill and Ted's magic telephone booth. Physicists at the Hong Kong University of Technology and Science have just proved that no machine will ever allow a person to travel through time because time travel is flat-out impossible. Not just unlikely, or we don’t have the technology yet, but, beyond the limits of the physical laws of the universe.

You might think time travel has always belonged in the world of fantasy, but 10 years ago some scientists began to believe time travel might actually be possible when superluminal -- or faster-than-light -- propagation of some specific medium were discovered. It was later found to be a visual effect, but the idea that a single photon could exceed the speed of light lingered, and with it, the possibility of time travel.

But in a study published in the peer-reviewed scientific journal Physical Review Letters, Shengwang Du and his team measured the ultimate speed of a single photon and showed that it cannot move faster than the speed of light.

Recalling a quote from Arthur C. Clarke:

When an aging and respected scientist announces that something is possible, he is almost invariably right. When the same scientist announces that something is impossible, he is almost invariably wrong.

Me, I refuse to believe that the warp drive is impossible.

http://techpaul.files.wordpress.com/2009/02/uss-enterprise-starship.jpg

[ixcuincle]

I am too lazy to find it, but Michio Kaku did a TV show in his sci-fi series on time travel. I think he said they would use wormholes or black holes, and navigate them throughout. He also mentioned some small molecular things...I don't remember, it was too long ago. Anyway that's a very interesting look at what Michio Kaku designed to deal with time travel in his sci-fi show.

[d0ublestr0ker0ll]

http://www.instructables.com/image/F5T3AF7FGZEMJ4G/DIY-Flux-Capacitor.jpg

[Chachie]

The Large Hadron Collider propels protons at each other over a 17 mile course at near light speed. I guess we now know why it's only near.

[HOF44]

We all time travel everyday at a steady rate into the future!!!

[Larry]

We all time travel everyday at a steady rate into the future!!!

Yeah, but that's only because I'm in the left lane, driving the speed limit.

[Hubbs]

Oh, bull****. Going faster than the speed of light is only one of the proposed ways that we could theoretically build a time machine, and from my limited understanding, it isn't one of the more promising ways.

[TheDoyler23]

If my calculations are correct, when this baby hits 88 miles per hour, you're gonna see some serious ****.

[mistertim]

We all time travel everyday at a steady rate into the future!!!

Actually it isn't a steady rate. Acceleration in the spacial dimensions causes time to slow down for the person experiencing it. Same with gravity (which is indistinguishable from acceleration according to relativity). So, really, any ship or vehicle that can accelerate is a "time machine" but usually the acceleration and velocity is such a small portion of the speed of light that its not noticeable. Also, if you had a ship that could hang out near an extremely massive object with an immense gravitational field, like a black hole, you would "time travel". Only thing is...this is all just time travel into the future, not the past.

[FanboyOf91]

If my calculations are correct, when this baby hits 88 miles per hour, you're gonna see some serious ****.


http://www.youtube.com/watch?v=atmwuQFRnjA

[Mickalino]

LAT: It's official: Time machines won't work

So, are they offering refunds on them ?

[mjah]

The Large Hadron Collider propels protons at each other over a 17 mile course at near light speed. I guess we now know why it's only near.
It's only near-light speed because it would require an infinite amount of time (or energy, depending on how you want to consider it) for those particles to actually reach light speed.


Going faster than the speed of light is only one of the proposed ways that we could theoretically build a time machine, and from my limited understanding, it isn't one of the more promising ways.
Came here to say the same thing. I don't think we have any chance at all of traveling through time in my lifetime, but I do recall that there are multiple proposed mechanisms for doing so. And perhaps others we don't yet know about.

It's a tricky thing to prove that something we don't fully understand is impossible in principle.

[Hubbs]

It's only near-light speed because it would require an infinite amount of time (or energy, depending on how you want to consider it) for those particles to actually reach light speed.


Came here to say the same thing. I don't think we have any chance at all of traveling through time in my lifetime, but I do recall that there are multiple proposed mechanisms for doing so. And perhaps others we don't yet know about.

It's a tricky thing to prove that something we don't fully understand is impossible in principle.

I've always thought that the proof that we won't invent a time machine that can travel back to this period is the fact that, well, nobody from 2387 has suddenly shown up in a time machine.

Now, you could buy into the "infinite multiverses" theory and say that in an alternate universe, somebody from 2387 has shown up. But, again, I find that to be pretty unconvincing, because if we really will invent a time machine that can go anywhere in time, then we're not just in the universe where one guy in one machine didn't make one of his stops, we happen to be in the universe where all of the people who traveled back in time haven't shown up even once. Each and every one of them forced one universe to spilt into two, and wouldn't you know it, we just happen to be in the one in which the time travelers didn't appear every single time.

(Granted, this does ignore the possibility that in the future, we'll be so very responsible and so very clever that we'll invent time machines that are invisible and establish some sort of Prime Directive which each and every time traveler always follows, resisting the temptation to break it 100% of the time. I find this unlikely. Human nature is what it is, and I don't expect it to have changed much in 100 years, or 1,000, or 10,000.)

I think it's more likely that if we do invent a time machine, it will be successful because of one of a couple theories I've seen about how we might be able to time travel, but we'll only be able to go back and forth between time after the time machine is invented, because the time machine essentially has multiple parts that move forward in time at different rates, and that's how we use it to travel—we get into the machine in one part that exists in one time, move to another part, and get out of the machine in that part's time. But all the parts are still only moving forward in time. They can't move backward, so there's still no way to travel to any point in time before the machine was first built.

On the other hand, I don't really know how any type of time travel into the past is possible if the multiverse theory isn't true, and I have my doubts. If it's not, then I don't see how you can overcome the grandfather paradox. It might be that time travel is a one-way phenomenon—you can go forward, but you can never go back.

[ixcuincle]

Sorry for the inverse, but it has to be like that to avoid copyright.

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To summarize, he is going forward and backward in time using wormholes and anti-matter

[Darth Tater]

I've always thought that the proof that we won't invent a time machine that can travel back to this period is the fact that, well, nobody from 2387 has suddenly shown up in a time machine.

Now, you could buy into the "infinite multiverses" theory and say that in an alternate universe, somebody from 2387 has shown up. But, again, I find that to be pretty unconvincing, because if we really will invent a time machine that can go anywhere in time, then we're not just in the universe where one guy in one machine didn't make one of his stops, we happen to be in the universe where all of the people who traveled back in time haven't shown up even once. Each and every one of them forced one universe to spilt into two, and wouldn't you know it, we just happen to be in the one in which the time travelers didn't appear every single time.

(Granted, this does ignore the possibility that in the future, we'll be so very responsible and so very clever that we'll invent time machines that are invisible and establish some sort of Prime Directive which each and every time traveler always follows, resisting the temptation to break it 100% of the time. I find this unlikely. Human nature is what it is, and I don't expect it to have changed much in 100 years, or 1,000, or 10,000.)

I think it's more likely that if we do invent a time machine, it will be successful because of one of a couple theories I've seen about how we might be able to time travel, but we'll only be able to go back and forth between time after the time machine is invented, because the time machine essentially has multiple parts that move forward in time at different rates, and that's how we use it to travel—we get into the machine in one part that exists in one time, move to another part, and get out of the machine in that part's time. But all the parts are still only moving forward in time. They can't move backward, so there's still no way to travel to any point in time before the machine was first built.

On the other hand, I don't really know how any type of time travel into the past is possible if the multiverse theory isn't true, and I have my doubts. If it's not, then I don't see how you can overcome the grandfather paradox. It might be that time travel is a one-way phenomenon—you can go forward, but you can never go back.
It is easy to overcome the grandfather paradox without the multiverse theory because the paradox assumes something that is not necessarily true. Remember, failure is always an option.

[Hubbs]

It is easy to overcome the grandfather paradox without the multiverse theory because the paradox assumes something that is not necessarily true. Remember, failure is always an option.

You seem to be implying that the universe would consciously know what you planned to do, and stop you every time. Sorry, the multiverse theory seems infinitely more probable than the Reverse Final Destination Theory.

[Larry]

So, are they offering refunds on them ?

No, but I bet soon we'll be seeing commercials on TV from trial lawyers:

"If you or someone you know has bought a time machine, then call us, and for a fee, we'll . . . "

---------- Post added July-27th-2011 at 07:02 AM ----------


You seem to be implying that the universe would consciously know what you planned to do, and stop you every time. Sorry, the multiverse theory seems infinitely more probable than the Reverse Final Destination Theory.

Remembering that Larry Niven once wrote a story about that. On Rotating Cylinders and the Possibility of Global Causality Violation.

[Kosher Ham]

If it could be made do you really think they would tell everyone.

[skinsfan_1215]

If time travel was possible, wouldn't there be future people walking around everywhere?

[Kosher Ham]

If time travel was possible, wouldn't there be future people walking around everywhere?

Who says they arent ?

[Dan T.]

So, are they offering refunds on them ?


His brother is looking for his money back:
http://2.bp.blogspot.com/_vp27qXrGhSY/R3kXEBwufwI/AAAAAAAAAi0/eFVBAI0uPwo/s400/Napoleon-Dynamite-fs21.jpg

---------- Post added July-27th-2011 at 11:10 AM ----------


If time travel was possible, wouldn't there be future people walking around everywhere?


Who says they arent ?

Indeed. Dude in sunglasses from 1940s:
http://www.boingboing.net/filesroot/201004161615.jpg

Woman caught on film talking on cell phone... in 1928:
TiIrpEMbQ2M

[China]

What?! But it's been done before. He assured me...

http://i205.photobucket.com/albums/bb141/ravin2979/Comment%20Pics/timetravel.gif