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Physicists Reverse Time Using Quantum Computer (phys.org)
fahrbot-bot shares a report from Phys.Org: Researchers from the Moscow Institute of Physics and Technology teamed up with colleagues from the U.S. and Switzerland and returned the state of a quantum computer a fraction of a second into the past. They also calculated the probability that an electron in empty interstellar space will spontaneously travel back into its recent past. The study is published in Scientific Reports.
Quantum physicists from MIPT decided to check if time could spontaneously reverse itself at least for an individual particle and for a tiny fraction of a second. That is, instead of colliding billiard balls, they examined a solitary electron in empty interstellar space. "Suppose the electron is localized when we begin observing it. This means that we're pretty sure about its position in space. The laws of quantum mechanics prevent us from knowing it with absolute precision, but we can outline a small region where the electron is localized," says study co-author Andrey Lebedev from MIPT and ETH Zurich. The physicist explains that the evolution of the electron state is governed by Schrodinger's equation. Although it makes no distinction between the future and the past, the region of space containing the electron will spread out very quickly. That is, the system tends to become more chaotic. The uncertainty of the electron's position is growing. This is analogous to the increasing disorder in a large-scale system -- such as a billiard table -- due to the second law of thermodynamics.
"However, Schrodinger's equation is reversible," adds Valerii Vinokur, a co-author of the paper, from the Argonne National Laboratory, U.S. "Mathematically, it means that under a certain transformation called complex conjugation, the equation will describe a 'smeared' electron localizing back into a small region of space over the same time period." Although this phenomenon is not observed in nature, it could theoretically happen due to a random fluctuation in the cosmic microwave background permeating the universe. The team set out to calculate the probability to observe an electron "smeared out" over a fraction of a second spontaneously localizing into its recent past. It turned out that even across the entire lifetime of the universe -- 13.7 billion years -- observing 10 billion freshly localized electrons every second, the reverse evolution of the particle's state would only happen once. And even then, the electron would travel no more than a mere one ten-billionth of a second into the past. The researchers then attempted to reverse time in a four-stage experiment by observing the state of a quantum computer made of superconducting qubits, instead of an electron. The researchers "found that in 85 percent of the cases, the two-qubit quantum computer returned back into the initial state," reports Phys.Org. "When three qubits were involved, more errors happened, resulting in a roughly 50 percent success rate. According to the authors, these errors are due to imperfections in the actual quantum computer. As more sophisticated devices are designed, the error rate is expected to drop."
Quantum physicists from MIPT decided to check if time could spontaneously reverse itself at least for an individual particle and for a tiny fraction of a second. That is, instead of colliding billiard balls, they examined a solitary electron in empty interstellar space. "Suppose the electron is localized when we begin observing it. This means that we're pretty sure about its position in space. The laws of quantum mechanics prevent us from knowing it with absolute precision, but we can outline a small region where the electron is localized," says study co-author Andrey Lebedev from MIPT and ETH Zurich. The physicist explains that the evolution of the electron state is governed by Schrodinger's equation. Although it makes no distinction between the future and the past, the region of space containing the electron will spread out very quickly. That is, the system tends to become more chaotic. The uncertainty of the electron's position is growing. This is analogous to the increasing disorder in a large-scale system -- such as a billiard table -- due to the second law of thermodynamics.
"However, Schrodinger's equation is reversible," adds Valerii Vinokur, a co-author of the paper, from the Argonne National Laboratory, U.S. "Mathematically, it means that under a certain transformation called complex conjugation, the equation will describe a 'smeared' electron localizing back into a small region of space over the same time period." Although this phenomenon is not observed in nature, it could theoretically happen due to a random fluctuation in the cosmic microwave background permeating the universe. The team set out to calculate the probability to observe an electron "smeared out" over a fraction of a second spontaneously localizing into its recent past. It turned out that even across the entire lifetime of the universe -- 13.7 billion years -- observing 10 billion freshly localized electrons every second, the reverse evolution of the particle's state would only happen once. And even then, the electron would travel no more than a mere one ten-billionth of a second into the past. The researchers then attempted to reverse time in a four-stage experiment by observing the state of a quantum computer made of superconducting qubits, instead of an electron. The researchers "found that in 85 percent of the cases, the two-qubit quantum computer returned back into the initial state," reports Phys.Org. "When three qubits were involved, more errors happened, resulting in a roughly 50 percent success rate. According to the authors, these errors are due to imperfections in the actual quantum computer. As more sophisticated devices are designed, the error rate is expected to drop."
And he can actually go to MIT and study statistics, like for really-real instead of lying 5 sigma insignificantly about it on slashdot, like a punk might do. The Lori Loughlin of statistics, stolen valor MIT, ridiculous. R = 0
then why did he have to steal the plutonium from libyians?
The experiment was about reversing entropy, not actually reversing the flow of time.
That is interesting enough, why make up stupid headlines?
Same thing happened a ways back about some chemist unboiling an egg, which some copywriters (not linked article) tried to make it sound like time was being reversed.
They did not "send it back in time" anymore than the antimatter travels back in time.
If time was a thermodynamic phenomenon, why doesn't shit get younger when you put it in the fridge?
Quantum mechanics defines the position of the electron as a probabilistic random model.
You calculated the probability of it moving back to the same place in that model.
You then measured that in a system that is cleaner, and it violated that probability.
Ergo you've disproved QM's random position model.
Rather than accept the QM model is wrong, you're disavowing causality and reversing time to fix it up.
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Probalistic model of electron
You're measuring the position of the -ve monopole. It's dancing around randomly and at seemingly infinite speed violating conservation of momentum, so Schrodinger declared it's position to be 'probablistic' to fix that up momentum problem.
That was a physics fix-up. An unproven one. Now you've proven it to be false (again). And again you won't accept the conclusion.
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The electron is moving with the oscillating electric F field. It is never 'smeared out', it is always in one place, it simply follows the best slot in the oscillating field as the field oscillates under it. It's doing no work, as long as it stays in the same slot in the field. It has no mass.
It will return to the same position at some multiple of F oscillations if you had it perfectly isolated in a perfectly clean F field. Or in this case, you're trying to force a clean F field to get it back to its original position.
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Resonant electric field is UNDENIABLE
1. Look, you've seen oscillations in particles
2. You know that all sub-atomic particles have charged components, even Neutrons can be spread into two charges. You observed this.
3. So you know that there is an oscillating electric field because oscillations + electric = oscillating electric field!
4. The existence of the oscillating electric field is UNDENIABLE.
5. That the field would even out, as it pushes and shoves, is also UNDENIABLE.
6. Resonance is UNDENIABLE.
7. And so the electron must be moving in that field, again UNDENIABLE consequence of the above thought experiment.
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8. And light must be moving over that field, because its electro-magnetic, it MUST BE RESONANT with the resonant field, because it is electric in nature! How could it move against resonance without experiencing the same pushes and pulls?
9. Since the motion of light is a result of this electric field, speed of light comes from the field, so the electric force (lets start calling it Electric-H0 ) must propagate infinitely fast. Speed of light comes from resonance, resonance comes from oscillations of electric-H0, so electric-H0 cannot depend on the speed of light.
10. So we have an oscillating electric field, lets call that electric-H1 whose oscillations at some arbitrary frequency F, match/drive the speed of light. i.e. motions over electric-H1 happen at the speed of light, because the speed of light is driven by those oscillations!
electric-H0 is the underlying force.
electric-H1 is the force oscillating at some universe frequency F.
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You only know electric-H1
11. You've only ever made electric forces using electrons, these are dancing in the F field, so you've only ever known electric-H1. You've never understood electric-H0 force, the models you have are for electric-H1.
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There is no mass.
Velocity isn't driven by momentum, which is driven by mass, which is created by velocity, which is driven by momentum, which is driven by mass, which is created by velocity, which is driven by momentum..... loop infinitely.
That was circular reasoning. It's difficult to let go of mass, and you keep trying to save it, even if it means screwing up time and space and everything else.
In classical physics it was 'quantity of matter'.
In modern physics its 'quantity of energy'.
In reality it's "measure of stickiness at current F". A useless metric!
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There *is* time
1. Consider a world where there is only two charged particles -ve, +ve. One force, electric, no ma
>> The physicist explains that the evolution of the electron state is governed by Schrodinger's equation.
They reversed a calculation on a quantum computer. Time was moving forward throughout the entire experiment.
Maybe some part of their algorithm might be useful somehow, but overall it seems like they were wasting time rather than reversing it.
This doesn't prove time reversal, it show a quantum computer can unreliably implement the Undo-Redo pattern.
Make Time Travel Great Again
1 in 10 billion in 13.7 billions years...
which should explain and predict the results seen. This is metastability and not time reversal.
Somebody tell Cher!
I thought time evolution in quantum mechanics was given by unitary operators, which are always invertible. What's so interesting?
I notice you omitted two things:
1. A defense of this 'reverse time' claim
2. A logical disprove of my claim.
Really, its sad, they've disproved Schrodinger, that's big news, big science, but that's not where the money is at. Congress science budget approved $1 billion for quantum conputing research (sic), and if you want to get a slice of that research fee, you have to suspend a little disbelief and pretend time is being reversed.
Without Schrodinger, the electron isn't in all places till detected and the quantum conputer isn't testing all solutions to find the optimal one. Poof there goes the budget and there goes the funding with it.
I reverse the time on my computer all the time and it's not a quantum computer.
You talk as if you can *in isolation* reverse time *for a single electron* and yet the forces from that electron are somehow disconnected from the forward time universe around it.
So all of physics is true for other electrons x = f(t), but for this particular electron x = f(-t) is true, at the same time x=f(t) for other electrons.
That's what the claim is here.
That electron is interacting with other things via the electric field, and yet somehow all its properties are reversed for a split second so it can move back to its original observed location.
Well either that, or an electron isn't dancing a random probabilistic dance until it's location is measured and Schrodinger was wrong.
Gee, I wonder which it is? Does measuring the location of an electron set the location of the electron, or did the electron always have a location whether you measured it or not?
In other news, the earth is the center of the solar system, and the planets are doing a probabilistic loop-de-loop to explain the observation of their apparent temporary backwards movement as they process around the earth..... IT'S THE ONLY EXPLANATION!
"in 85 percent of the cases, the two-qubit quantum computer returned back into the initial state," ... According to the authors, these errors are due to imperfections in the actual quantum computer.
Maybe the amazing headline result is due to one of these errors, rather than the null hypothesis being due to errors?
Corruption is convincing someone that the selfless ideal is the same as their selfish ideal.
nothing to defy the laws of physics, especially and including time travel
Politics is Treachery, Religion is Brainwashing
This isn't reversing time, it's zeroing bits.
Make Time Travel Great Again
Much better than the Democrat's desire for the 1850s.
How DARE you leave the thought plantation!
I can't believe it. We finally have a working time machine. It's fantastic. Amazing. I don't know who to thank first... When will I be able to purchase one for my home, for my daily walks which have in recent years become implausible due to the destruction of these once-idyllic neighbourhoods?!
I had read the original article. They did not actually reverse time. What they did was cause events that normally only go one way in time to go the other way: e.g., breaking an egg - one can't cause an egg to re-assemble. Well, they did, so to speak. But it did so in the forward time direction.
... why Deja Vu happens...
The electron is not moving back in time. It is recreating a past state, but in the present time frame. It is not possible to actually measure backwards time travel without the observer also moving back in time. These are my thoughts on the subject.
I'm always doing stuff over and over again.
It always makes me feel like I am time traveling.
For this reason, God sends them a powerful delusion(operation of wandering)(planet) so that they will believe the lie.
Mystery Red of the Great American Eclipse
It has blood on it!
ABCNews: Eclipse makes pendulum wander
Sound of Silence
Sun researchers find strange eclipse reading
Is this accomplishment an implementation of reversible computing?
Decentralization: the brief interval between the decline of one centralized regime and rise of another.
These will have been my thoughts on the subject.
FTFY
The convention on Time Travel will be held last week. Tickets went on sale next month. Get yours yesterday before they run out!
Great civilizations have lived and died on false theories. Don't mess up mine with a few facts.
I came here to say that phase conjugation is not time reversal but I thought about it some more and there are limited ways you might call it pseudo time reversal.
Phase conjugation of a light wave is old stuff. When you do it reverses the direction a shaped wavefront propagates. Since the argument of a wave function f(k*z-w*t) goes backwards when you change the sign on t it's mathematically the same as making time negative. So the wave goes back to where it came from. Notably if it went through phase distorting media then the distortion is not doubled but actually is undone leaving the wave just as it was on the way out.
However if the media was attenuating the wave is not magically amplified on the way back!
So it's not really sending it back in time. It's just phase reversal or conjugation .
The same thing happens in NMR and things like Rabi frequencies. And photon echos.
The same will be true in QM. All they did was created a photon echo.
Except this is with matter not photons so it's pretty banned cool and you don't need to make it sound cooler by sayin it went backward in time.
Keeping matter coherent enough to phase conjugate us aswesome!!!
But I'll note how you could actually time reverse. That would require making the whole container phase conjugate. If we phase conjugated a photon and an attenuating medium the the photon would be amplified so really time reversed!
Some drink at the fountain of knowledge. Others just gargle.
I can't wait to see if this was a IEEE floating point rounding problem.
Democrat's don't want to carry us back then. There were no social programs then (it's a wonder anybody survived).
No. They want to transport us physically....to Russia...so they can have their full-fledged socialism.
Aah, change is good. -- Rafiki
Yeah, but it ain't easy. -- Simba
There were no social programs then (it's a wonder anybody survived).
Actually, there were social programs in the 1850s, in the form of jobs programs that came out of...
Reconstruction
Transcontinental railroad
Expanding the military
Republicans today like to whine about big government, except they forgot that it was the party of Lincoln that expanded government greatly in the Civil War and kept it that way after it ended. This paved the way to the Progressive movement.
It was actually just ntpd!
Naive interpretation or summary.
This is like trying to drive in reverse to spin back the odometer. Even if it did spin back, it doesn't mean that the car is magically newer again.
A record player arm plays the record and returns to the starting position. Time was reversed!
A wheel turns one full revolution and returns to the original orientation. Time was reversed!
A door opens and then closes. Clearly, time has gone backwards!
I order a drink in a bar, drink it, and the waiter refills the glass. Whoa, mysterioso Jules Verne stuff going on man!
Yeah, probably not the same thing as this experiment, but the point remains. Calling this 'time travel' is uber-Dumb.