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Weird Science: Can Time Move Backwards?

Time_travelJohn Cramer, a physicist at the University of Washington, believes that light particles can act in reverse time, and he has compelling evidence behind his theory. Cramer is a well-respected experimental physicist with an impressive particle physics background.

The reality is that two subatomic particles split from a single particle do seem to somehow instantaneously communicate, regardless of how far apart they get in space and time. The bizarre phenomenon is described as "entanglement" and "non-local communication." Cramer believes he may be able to solve the mystery of how these particles react thousands of miles apart. His theory rests on a sort of time travel called quantum retrocausality.

Unfortunately, his ideas are so radical that none of the usual establishments, like NASA's Institute for Advanced Concepts, are willing to support his research. Like other “forward thinking” agencies, the branch of the military-science-industrial complex known as DARPA (Defense Advanced Research Projects Agency) also couldn’t wrap their minds around a “backward” concept that time can move in reverse. They rejected Cramer's proposal as "too weird”. This from an agency currently using tax dollars to support research aimed at creating killer “Terminator” liquid robots, you know—normal stuff!

"This country puts a lot more money into things that seem to me much crazier than this," said Mitch Rudman, a music industry executive in Las Vegas whose family foundation donated $20,000 to the experiment. "It's outrageous to me that talented scientists have to go looking for a few bucks to do anything slightly outside the box."

Cramer had all but given up his dream of unlocking the secrets of the space/time continuum, when individual supporters like Rudman started sending him checks in a grass roots effort to support innovative scientific research. It seems only the public will support something truly “outside the box” (or at least outside the box in a way that doesn’t involve killer liquid robots).

"He's looking into the fundamental qualities of the universe," said Denny Gmur, a scientist who works for a biotechnology firm in Bothell. "I had $2,000 set aside to buy myself a really nice guitar, but I thought, you know, I'd rather support something that's really mind-boggling and cool."

As a physicist, Cramer has been interested in this research for decades, because it could potentially resolve a fundamental paradox of quantum mechanics, the theory that accounts for the behavior of matter and energy at subatomic levels, called the Einstein-Podolsky-Rosen paradox.

In the 1930s, Albert Einstein and two other scientists (Rosen and Podolsky) attempted to disprove quantum theory. Einstein didn't like how it seemed to require subatomic particles to interact faster than the speed of light, heaven forbid.

A few unsatisfying efforts have been aimed at solving this puzzle, but there has never been any conclusive research for how subatomic particles communicate through time and space. Cramer proposes an explanation that doesn't violate the speed of light, which was Einstein’s objection to the theory.

"It could involve signaling, or communication, in reverse time," says Cramer.

Physicists John Wheeler and Richard Feynman promoted this idea of "retrocausality" as worth considering years ago, but it still remains untested. Cramer's version would be aimed at using retrocausality to resolve the EPR paradox. He dubs it the "transactional interpretation of quantum


Other notable physicists, such as the famed cosmologist Stephen Hawking, believe that time can only move forward. Cramer responds to that objection quite simply—there is no proven reason why time can only move one way. Basically, until someone proves otherwise, there’s no good reason why time can’t move backwards.

His proposal is a relatively simple experiment requiring lasers, prisms, splitters, and fiber-optic cables to see if he can detect "non-local" signaling between entangled photons. If he is successful, then he is likely to get support from "traditional funding sources", at which point he’ll have the money to acquire the needed equipment to test for photons communicating in reverse time.

His supporters are somewhat of a maverick crowd themselves, like businessman John Crow who donated $3,000 from his own pocket.

"I'm just a crass businessman, but in business we know high risk offers high reward. This isn't that much money to find out if time can go both forward and backward," says Crow.

"Heck, if it works we can go back in time and get our money back!" he laughs.

Retired physicist and rocket scientist, Walter Kistler, who started Redmond-based Kistler Aerospace, donated $5,000 as well. Kistler's struggled for years unsuccessfully promoting the concept of reusable rockets, even going bankrupt once. His company recently won a NASA contract.

"I know how difficult it can be to get people to even consider new or unusual ideas," he said. "Even Einstein had trouble accepting the basic ideas of quantum theory. I've talked to professor Cramer, and what he is trying to do could be very important."

Richard Miller, an artist and photographer who also made a contribution isn’t worried about the possibility of failure.

"I would say the predicted failure of this project is probably a good omen," he says. "Most predictions are wrong."

Rudman, the Las Vegas music mogul, relates another reason for contributing, "The rare hits we get

every once in a while pay for all the stiffs, and then some," Rudman said. "If this stiffs, it stiffs. But, man, you've got to try, don't you? You've got to be willing to take the risk of being wrong to find something new."

The University of Washington has set up a special account to which individuals or groups can contribute funds for John Cramer's experiment.

Tax-deductible contributions to the project may be made by contacting Jennifer Raines, UW Department of Physics, at, or mailing a check made out to the University of Washington with a notation on the check directing deposit to the account for "Non-Local Quantum Communication Experiment" to:

Jennifer Raines, Administrator
Department of Physics
University of Washington
Box 351560
Seattle, WA 98195-1560

Posted by Rebecca Sato

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Why not? If mind have power to see past and future ( im talking about ESP which is fact bcoz I experienced it, not imagination) then those particles that made this to happen really can communicate outside the present time. i think this is one example that there are existing particles that can help us make our dream of travelling in time possible.

I would like to point out that NIAC did not turn down John Cramer's proposal. His proposal, like dozens of others, was in the midst of a peer review process, and it might have been a funded proposal, but that peer review process had to be canceled as NASA has terminated its funding for NIAC. The NIAC funded credible ideas that represent advances in systems and architectures and because of it, a constellation of creative, valuable ideas have emerged to change the way many think about our future possibilities.

I for one will be watching John Cramer's progress with great interest.

Diana Jennings, PhD
Associate Director, NIAC (for a little while longer)

If it did work then wouldn't you think that he would have come back already? Unless your doing it as an observation anything you do to the past will change the future

Joseph I find your comment really irritating because it doesn't make any sense whatsoever.
At the moment it's only a hypothesis that reverse time travel is possible, there's yet sufficient evidence to back up the hypothesis. And that's why he's trying to gain funding so he could establish his research. So no Joseph "it" (whatever you mean) doesn't work and he wouldn't have came back. Infact where did he go in the first place and came back from where? And based on which Futurama episode for you to say that anything you do in the past will change the future? I'm a fan of Futurama too.

No, if it worked, he could not come back. This has not much to do with time travel.

We are talkin microscopical nanoseconds here.

Anyway, for enthiusiasts of "timetravel": knowing how something works, does not always allow you to operate it.

Time does not work that way. What happens, stayes happend.

Here we are trying to find out how some fundamentals of the universe work. Try operating the universe - its eternal, beat that first!

Pierre, I can't take you seriously that ESP is fact when you can't spell because.

If something can move forward, I don't see why it can't move in any direction. What is "forward" anyways but our perception of direction?

Seems natural that anything that can have motion would be able to move in any direction.

Is there anything in the Universe that only moves in one direction?

We know so little about time, to say it is for sure any one thing would be ignorant.

Time moves forward, it seems to move sideways too with an infinite number of parallel universe.

If time went forward, then it would seem that there is a record of whathappened previously and it would only be a matter of being able to see this stuff.

Isn't view old light waves a form of time traveling? Maybe it's all perception.

And does Merlin have anything to do with this. Since Merlin the Magician was said to age backwards. A concept I didn't find that unusual.

To me, anything that goes forwards would logically be able to go backwards.

Seems to me time is moving forward based on some sort of weird cosmic inertia.

Maybe time is just the expenditure of energy from the big bang/big bounce.

I wish I had completed my Jr High math classes.

If retrocausality were to occur then there would be a limit on how far you could travel back in time. Since energy can not be created nor destroyed there would be a time limit such that this law would not be violated.

Even if you can look into the past and see a previous time, that doesn't mean that you can travel there.

Seeing light waves from the past doesn't mean that you went back in time, all you did was see light that just now got to you. It may be really old light, but it is still in the current time.

Also, even if a scientist could see particles that communicated backwards through time, that doesn't mean that this time travel could be harnessed by us anytime soon (or at all) for this scientist to travel back and prove it to us.

Hmmm, if communication to the past is possible with technology, it seems to me that there would have to be some type of technology in the past with which to communicate through. Since such technology does not exist yet, actual communications with the past will not be possible until after the technology already exists. At the point in time of that technology being invented, the first message would not be from the past, but from our future, where they are then communicating into the past, out present. Of course that future would ostensibly be mere minutes or hours in the future. So, at that point in time, in order to obtain needed funding, the future should communicate the lottery results in time for the past to place the bet. Problem solved. Oh, wait, they need funding first. Darn.

Ha ha... far out.

Seriously, we are not talking about time travel here. We are talking about the possibility that time flows in both directions.

Perhaps in the future such a concept, if proven, would allow someone to figure out a way to communicate from future to past, but then only back as far as the time when such needed equipment is devised. --And to what end?

The only way I can think of *at the moment* would be in a special Q.M. super-computer (such as they are trying to build even now), where different computations could be undertaken and the future machine will send back a photon (or other wave/particle) with either of a couple different spins, telling the earlier machine "yes" or "no" ["yes that works" or "No, that didn't work -try a different computation."]

And of course, here we get into the many worlds concept, inasmuch as when the earlier machine ceases its first computation and starts a different one, then the future from which the answer was returned no longer exists, at least for our version of reality. Ignoring for the moment the practical problems of how a particular photon could be picked up as being the one with the answer from the future... It's an astronomically insurmountable problem, I would say.

No, I don't believe that retro causality is time travel, but aren't we talking about two sub-atomic particles being related in such that they can communicate through vast differences as though they were still connected? So wouldn't this suggest closer to something like a fourth dimension, reverse time seems possible too considering our lack of knowledge of time, but it seems more likely to me that the particles in this case still be connected in a fourth so that communications be instant between the pair. These are radical hypotheses, but in any case a hypothesis is required before it can be either disproved or proven. It is definitely worth research however, and I will be following the trail to see how it goes, I'd help if I could. Mail me if you get the chance, anyone, to discuss the topic more in-depth

I hope this does work because time travel would be amazing. I think I may of witnessed some today because i saw two clocks skip backwards at the same time and then skip forwards at the same time rite after it was only five seconds backwards and forwards but still kind of amazing.

Some people...
"Oh yeah, I think I saw some time travel today."


What goes up must come down. Everything seems to balance it self out, so if time goes forward why not backwards? How do we know we are actually going forwards in time, it's just the concept we have....maybe we are going backwards! What really are black holes? Are they reverse to stars exploding hence another concept of time going backwards... maybe time is on different that spelt right..? there is an equilibruim and we do not understand time yet as having it's own balance! I welcome any comments?

Time. Time is an equation that our human minds have created. Time does not actually exist. Even by our own infinitesimal understanding, existence and understanding of it, on the grand scale of the universe--it simply does not exist, it never has existed and it will never exist.

Many of us are told "Oh well, that can't be possible because it can't be explained". This is the biggest flaw in our evolution as a race in our universe. This is what so many people in history have thought until someone has been able to scientifically prove otherwise. At this very moment, someone is coming up with an idea or proposition of which they have experienced that simply can not be explained. This only happens because so many humans on this planet simply can never understand or comprehend it. That is another flaw in the evolution of our human brains. Still yet history and science has proven that we have all evolved in to our species as it is today--and we exist because somehow, somewhere, someone thought differently and survived ultimately in the past so that we are now sitting here typing in our computers on the wonders of the technology of the internet.

Some minds/brains will simply never be capable of being able to understand the concept of time. Only a very tiny portion of our human race are capable of understanding it, and the rest are not. That's just the way it is.

Having said all of this--even if we could send particles back in time, how would we know we sent it? Even if we were traveling back in time, how would we even know it? Even if right now particles are traveling backwards in time, how will we ever even notice?

My friends, we are all completely out of sync with time relative to everything else in the universe. At this very moment every single one of us is traveling at nearly 2 million miles per hour. If we were all to travel 341 times faster, we would all completely freeze in time because we would achieve the speed of light--and yet we would be completely unaware of it. This calculation is relative to the universe, and based on the theory of relativity.

So if we were to step off Earth, and travel to another galaxy, or even find a stationary position in the middle of nowhere in a stationary position relative to the universe--we would become out of sync and we would never even be aware of it.

Or are we really out of sync? Or is time a formula that we got wrong based on the revolution of our planet around the sun? Does time even matter? No it doesn't. It's this bending and refraction of time as we know which causes us to believe in dark matter and other unknown phenomenon. We are trying to explain something that simply does not exist, and something that our inherently flawed brain/mind can not comprehend or understand.

The answers to our most puzzling questions about our existence and our universe are so very simple to explain and understand. The problem is, our brains are not capable of fathoming or understanding it all--and most likely never will when you look at the grand scale of the universe. It simply is not meant to happen.

This goes far beyond the thinking of Stephen Hawking and Albert Einstein. You read it here first.

time is constant as sir Issac newton said. ya there is Einstein relative theory of time but this theory is based on two different velocity where velocity is distance covered per unit time hence time is constant i think. its just that the more the speed lesser time require to cover for given distance,its not that time is traveling slower compare to other body travelling at lower speed.

time, an illusion. quite likely, although.... for all we know our existence itself is an illusion, so why are we contemplating time (a concept that few people even have a clue what it might be) when time as we can see it is irrelevant to look at, since it only goes forward with our present perception. if time is an illusion, so what? illusions make up everything we know, our mind makes illusions for us every day, for instance, what do you think would happen if a particle was shown to us and no one looked at the particle? and the majority believed it didn't exist? that's simple, to every person that was told that it wasn't existent or was never told about it, it would be non-existent to them excluding those people that doubt what we are told. here's another thing for you all. the fact that we observe something means that its nature changes, if you shoot molecules through 2 slits in a wall that are parrallel to eachother, and watch them, there will be 2 lines on the other side where the molecules hit, but if you dont watch them, the lines will show up as if waves where being shot through these slits, not normal molecules.

truely fascinating............

No, i dont think that once time gone can come back,but someone putting a lot of effort can make the things possible.

no i dnt think time can travel backwards..time,as water,flows only in a single direction...hence we cannot travel to our past nor can time flow backwards creating paradox....

If light speed is constant
If you travel in rocket going close to speed of light, time would slow down.
If you could go faster than speed light, then time would have to go backwards

when a theory is disputed and reasons are given why it can't be,then an experiment proves it's factuality the answers to the disputed questions become apparent for the most part.

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