Is this the time travel breakthrough?

Calling Tom Bedlam, come in Tom!

Personally I have yet to read any theory on ATS that is similar to this and although time travel is not high on my list of interest I was a bit intrigued by this:

One of the most replayed commercials on television right now is the DirecTV ad with Doc Brown from Back to the Future. Doc, we learn, has forgotten to tell Marty McFly to buy DirecTV in the future. Never mind that the 1955 version of Doc never traveled through time, and therefore wouldn't know about DirecTV. More importantly, how's that whole time machine thing coming? When can we rev up the DeLorean and, like Marty, go to our parent's high school dance with our mother?

Never. But not never, never. Just never for us. First, back to the basics.

A physical time machine—a device available at Wal-Mart, as opposed to a natural wormhole somewhere in the cosmos—is possible. You begin with something square. Next, install mirrors at the corners and send a beam of light, perhaps from a laser, at one of the mirrors. The light will bounce to the second mirror, the third, the fourth and back through this cycle forever.

The force of this constantly circulating light will begin twisting the empty space in the middle. Einstein's theory of relativity dictates that everything happening to space must happen to time, so time begins twisting, too.

To fit a human inside this time machine we need to stack a bunch of these mirrors on top of each other, and add more light beams. Eventually, we'll have a cylinder of circulating light. Once we step inside, we're ready to fly through time.

Rubbish, you say? Well, unlike Doc Brown's second-generation DeLorean, which ran on garbage, the model for our time machine is actually testable. Place subatomic particles—pion or muons—on one side of the light cylinder, and a particle detector on the other side. Then send the particles across. Because these particles all live for the same amount of time—about a millionth of a second—they should all reach the detector at the same instant. Unless, of course, a time loop exists inside our light cylinder.

As soon as this time machine is built, time travel will commence, and continue to exist until someone turns off the machine. Here's the catch: The time machine only allows someone to travel as far back as when the machine was first activated. Since no time traveler has shown up yet—check-out aisle tabloids notwithstanding—no such machine has yet been invented.

These are the boundaries of time travel. If the machine is left on forever, you can travel forward forever, but you can't go back before the machine was built.

So, we can't travel back to our mother's high school prom. But, putting incest matters aside, it's conceivable for some future Marty McFly to do so. In this scenario, even if Marty interrupted the meeting of his parents, he would continue to exist—the picture of his family that fades in the movie would remain intact in our new world.

Instead, as soon as he stepped out of the light cylinder, a parallel universe would begin. Marty can alter this new universe if he'd like—perhaps even take credit for "Johnny B. Goode" and become a famous musician. He can even travel in time within this parallel world. But once the new universe changes, he's unable to return to the original one. (In which case, I call dibs on his girl Jennifer.)

It's all a bit confusing, which brings us back to Doc Brown's anachronistic advice in the DirecTV ad. The commercial's real take-home message is that, 22 years later, Christopher Lloyd looks great. Which just goes to show that, for now, a time traveler is only as good as his make-up artist.

That's interesting.

Do you have a link?

Oops! Sorry about that!

www.smithsonianmagazine.com...

As soon as this time machine is built, time travel will commence, and continue to exist until someone turns off the machine. Here's the catch: The time machine only allows someone to travel as far back as when the machine was first activated. Since no time traveler has shown up yet—check-out aisle tabloids notwithstanding—no such machine has yet been invented.

I don't really agree with this part . Why wouldn't you be able to travel back in time before the time you built the time machine ? I think this rule would only apply if ,somehow , going back before the time you create the machine would implicate on you building it in the first place .

Like in "The Time Machine (2002)" . No matter what the time traveller did , his girlfriend would always die in the end because if she didn't he would have never created the time machine therefore being unable to go back in time .

Man , I love to discuss time travel .

Sorry to break it to you, but Back To The Future was only a movie!

ok, forgive me if I am wrong - but shining a light at mirrors to infinity to create some 'wormhole' - that just doesn't make sense... perhaps I read the article wrong - but wouldn't that just create some kind of high energy beam or anomaly that would incinerate any living tissue?

Hmmm. Sounds like a lot of lasers and mirrors to me! So, how do you control when and where you go to? How do you get back? Does the "machine" go with you?

The article was published by the Smithsonian and written by a theoretical physicist, so the credentials are there from a layman's perspective. But, me being cynical, he's also got a book to sell.

Time travel discussions invariably tie me in knots, but I can't resist them

Grey

Originally posted by jbondo
Calling Tom Bedlam, come in Tom!

Personally I have yet to read any theory on ATS that is similar to this and although time travel is not high on my list of interest I was a bit intrigued by this:

Hrm. Well, Mallett is a theoretical physicist, and a good one, but he has a bug up his arse on the entire time travel thing. Not that that's bad, mind you. He would have you believe that his theoretical framework is a done deal, cut and dried, just needs to be tested. However, he used a singularity in his model to make the math work, and there's other reasons to believe that won't work that are beyond my level of math to say yes or no.

If you're into detailed rebuttals that invoke general relativity, here is the link:
arxiv.org...

It will be interesting to see if his frame-dragging lab experiments work, and if not, how they come out.

His use of mirrors to make his infinite cylinder of light require not only unearthly perfection, but also seem to pose several problems. First, a real mirror will interact with the light on each reflection, losing energy in Maxwell dissipation in the mirror. The photons will drop in frequency with each reflection until they are of such a long wavelength they pass through.

Next, unless the mirrors are infinitely rigid, each reflection imparts momentum to the mirror in terms of phonon interaction in the mirror's base material, with the lasers again losing energy to the mirror and either being absorbed, penetrating or dropping in frequency.

At the energy densities he's talking about, nothing material would do.

A lot of times you have to assume unnatural perfection in your materials. That can also end up with you assuming something will work that can't be made to work practically. For example, all you need to time travel is an infinite rotating cylinder (see Tipler). We're fresh out of them though.

That's not to say that his stuff doesn't seem creepily close to one of those projects that's a Big Hairy Deal, in an indirect sort of way. Thanks for pointing the article out to me, I passed it along to a friend. Now he can get an ulcer for his country.

From what I understand you end up with a circular vortex of light which you then step into (the center). Once you go back to your target time you then merely step out.

I guess the danger of skewing or creating a new time line could come into play. However, I would think that the reason you can't go back further than the machine was first fired up is because the machine wouldn't be there as it wasn't invented yet.

OK, now I'm confusing myself!

Originally posted by jbondo
From what I understand you end up with a circular vortex of light which you then step into (the center). Once you go back to your target time you then merely step out.

I guess the danger of skewing or creating a new time line could come into play. However, I would think that the reason you can't go back further than the machine was first fired up is because the machine wouldn't be there as it wasn't invented yet.

OK, now I'm confusing myself!

Exactly, very confusing!

But, how do you know you've reached your target time? If you can't get back to before the machine was invented....no. No, I'm not going to ask any more!!!!! No!

I sort of understood around a third of Tom's post and figured out the gist from that. But, this whole time travel thing is so full of anomolies and paradoxes (sp?) that it makes my brain hurt.

Please stop posting in this thread folks or I'm going to end up in hospital.

Grey

Originally posted by Tom Bedlam
Hrm. Well, Mallett is a theoretical physicist, and a good one, but he has a bug up his arse on the entire time travel thing. Not that that's bad, mind you. He would have you believe that his theoretical framework is a done deal, cut and dried, just needs to be tested. However, he used a singularity in his model to make the math work, and there's other reasons to believe that won't work that are beyond my level of math to say yes or no.

Deja vu?

Tom, am I losing my mind or did you post something similar before?

Tom, am I losing my mind or did you post something similar before?

[edit on 7-3-2007 by jbondo]

Originally posted by jbondo
Calling Tom Bedlam, come in Tom!

Personally I have yet to read any theory on ATS that is similar to this and although time travel is not high on my list of interest I was a bit intrigued by this:

One of the most replayed commercials on television right now is the DirecTV ad with Doc Brown from Back to the Future. Doc, we learn, has forgotten to tell Marty McFly to buy DirecTV in the future. Never mind that the 1955 version of Doc never traveled through time, and therefore wouldn't know about DirecTV. More importantly, how's that whole time machine thing coming? When can we rev up the DeLorean and, like Marty, go to our parent's high school dance with our mother?

Never. But not never, never. Just never for us. First, back to the basics.

A physical time machine—a device available at Wal-Mart, as opposed to a natural wormhole somewhere in the cosmos—is possible. You begin with something square. Next, install mirrors at the corners and send a beam of light, perhaps from a laser, at one of the mirrors. The light will bounce to the second mirror, the third, the fourth and back through this cycle forever.

The force of this constantly circulating light will begin twisting the empty space in the middle. Einstein's theory of relativity dictates that everything happening to space must happen to time, so time begins twisting, too.

To fit a human inside this time machine we need to stack a bunch of these mirrors on top of each other, and add more light beams. Eventually, we'll have a cylinder of circulating light. Once we step inside, we're ready to fly through time.

Rubbish, you say? Well, unlike Doc Brown's second-generation DeLorean, which ran on garbage, the model for our time machine is actually testable. Place subatomic particles—pion or muons—on one side of the light cylinder, and a particle detector on the other side. Then send the particles across. Because these particles all live for the same amount of time—about a millionth of a second—they should all reach the detector at the same instant. Unless, of course, a time loop exists inside our light cylinder.

These are the boundaries of time travel. If the machine is left on forever, you can travel forward forever, but you can't go back before the machine was built.

So, we can't travel back to our mother's high school prom. But, putting incest matters aside, it's conceivable for some future Marty McFly to do so. In this scenario, even if Marty interrupted the meeting of his parents, he would continue to exist—the picture of his family that fades in the movie would remain intact in our new world.

This is a pathetic, cringeworthy example of cargo cult physics abuse. The writer neither understand relativity or even basic physics. I'd waste no further time on it.

[edit on 7-3-2007 by disownedsky]

disownedsky,

Mind letting us in on the secret?

Actually, it's not so cringeworthy that it hasn't drawn a lot of interest including formal rebuttals in respected peer-reviewed journals.

I just think he's wrong, but I'm not in his league.

Disownedsky, Mallett's original work was also published in peer-reviewed journals: www.physics.uconn.edu...

My first take on it was that it's a sort of "kugelblitz" reversal of Tipler's original work "Rotating Cylinders and the Possibility of Global Causality Violation", most certainly not cringeworthy, only Mallett is trying to use photon frame dragging inside a cylinder instead of gravitational frame dragging outside as Tipler did.

But it turns Greek on me pretty fast. (McCoy voice ON-) Dammit, Jim, I'm a UFO mechanic, not a chronophysicist!

jbondo

Deja vu?

Tom, am I losing my mind or did you post something similar before?

Tom, am I losing my mind or did you post something similar before?

Wasn't there another time travel thread not long ago? Heh..look into Mallett's paper and he invokes Kerr metrics right off, that's the thing I was telling you about on that thread where you spin a black hole until it forms a doughnut.

[edit on 7-3-2007 by Tom Bedlam]

As soon as this time machine is built, time travel will commence, and continue to exist until someone turns off the machine. Here's the catch: The time machine only allows someone to travel as far back as when the machine was first activated. Since no time traveler has shown up yet—check-out aisle tabloids notwithstanding—no such machine has yet been invented.

This reminds me of the movie Primer, which was a great time travel movie.

Abe and Aaron confirm that they have accidentally created a time machine after they test the device on their watches. The device is unlike a traditionally envisioned time machine; it can only "travel" back to its turn-on time, and the user must spend as much time in the machine as he wants to go back. They first use their machines to succeed in the stock market, but as they begin to explore how the machine can allow them to alter not only their personal lifestyles but how they are perceived by the people around them, ethical and philosophical dilemmas soon ensue regarding the applications and dangers of the machine. The film explores different individuals' reactions to the power of foreknowledge, the temptation of correcting the smallest detail of one's life and the ramifications of that abuse of power as it inevitably affects on a larger and unforeseen scale.

Well, it is certainly true that photons (electromagnetic fields) are also source terms of the Einstein field equations and contribute to the stress-energy tensor, like mass. Classically there's the usual E^2+B^2 energy density and some cross terms.

The problem is that the energy density necessary to do anything as a source of gravitation is so preposterously large that it is impractical.

How much gravitational effect---i.e. as *creating* gravity does 1 gram of matter have? An absolutely tiny amount. The entire mass of the Sun can deflect starlight by fractions of a degree.

Now if you convert 1 gram of matter to photons, as E=mc^2, (e.g. antimatter annihilation) how much would that be? One hell of a BOOM and a FRY.

That level of energy density gives (roughly, as the terms are not exactly identical) the gravitation source effect of 1 gram of matter. Yow!

To have major exotic effects, you need just soooo much more, as in neutron star level densities.

So the intensity of the electric & magnetic fields would be so unbelievably ridiculously high that any matter nearby would be utterly fried, like the mirrors, and it would be so strong that you'd get spontaneous creation of e+/e- pairs, and maybe even p+/p- pairs and exotic stuff and it would turn into one uncontrollable matter/anti-matter plasma with hard gammas which can't be controlled or engineered to do anything.

Mallat's paper doesn't attempt to plug in any numbers.

Wouldn't it take a tremendous amount of mass to have any effect on local space at all? At least enough to begin twisting space? I don't think photons have the necessary mass.

Of course, I'm just a Missouri hillbilly. I think I hear a turkey gobblin'!

EDIT to add: Aw crap! I think mbkennel expressed this much more elegantly!!

[edit on 7-3-2007 by MrPenny]

Originally posted by mbkennel
So the intensity of the electric & magnetic fields would be so unbelievably ridiculously high that any matter nearby would be utterly fried.

This is what I was thinking and I can't see any way around it. However, would it effect something inside the vortex? I would think as it spins the destructive effects would happen only on the outside. Could there be a dead calm area such as in the eye of a hurricane?

That last movie mentionec sounds interesting. I'm going to have to watch that.

That was certainly my first response to it, which is why I called it a "kugelblitz version of Tipler".

Kugelblitz's are black holes formed by an ungodly concentration of energy, a collection of photons sufficiently dense so as to form a singularity from their relativistic mass.

What I meant by it was that if you can do the trick through Tipler using an infinite cylinder, then you could probably do the same with energy if you got its density up high enough to have the same effect. Only you couldn't generate that, and you couldn't contain it, and hell, you might as well just invoke an infinitely long rotating cylinder and be done with it.

I have heard that Mallett got the time travel bug due to his father dying - he wants to make it didn't happen. Wikipedia has the same cite, for what it's worth.

Originally posted by netobrev
As soon as this time machine is built, time travel will commence, and continue to exist until someone turns off the machine. Here's the catch: The time machine only allows someone to travel as far back as when the machine was first activated. Since no time traveler has shown up yet—check-out aisle tabloids notwithstanding—no such machine has yet been invented.

This reminds me of the movie Primer, which was a great time travel movie.

Abe and Aaron confirm that they have accidentally created a time machine after they test the device on their watches. The device is unlike a traditionally envisioned time machine; it can only "travel" back to its turn-on time, and the user must spend as much time in the machine as he wants to go back. They first use their machines to succeed in the stock market, but as they begin to explore how the machine can allow them to alter not only their personal lifestyles but how they are perceived by the people around them, ethical and philosophical dilemmas soon ensue regarding the applications and dangers of the machine. The film explores different individuals' reactions to the power of foreknowledge, the temptation of correcting the smallest detail of one's life and the ramifications of that abuse of power as it inevitably affects on a larger and unforeseen scale.

Yup, Primer is actually one of my favorite movies. If any of you guys like this thread, then do yourselves a favor. Go to the movie store and pick up Primer, it's an excelent movie. I also think it's been on HBO recently, so if you have that, look for it in the future.