Credit: @tsarcyanide/MIPT

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.

"This is one in a series of papers on the possibility of violating the second law of thermodynamics. That law is closely related to the notion of the arrow of time that posits the one-way direction of time from the past to the future," said the study's lead author Gordey Lesovik, who heads the Laboratory of the Physics of Quantum Information Technology at MIPT.

"We began by describing a so-called local perpetual motion machine of the second kind. Then, in December, we published a paper that discusses the violation of the second law via a device called a Maxwell's demon," Lesovik said. "The most recent paper approaches the same problem from a third angle: We have artificially created a state that evolves in a direction opposite to that of the thermodynamic arrow of time."

What makes the future different from the past

Most laws of physics make no distinction between the future and the past. For example, let an equation describe the collision and rebound of two identical billiard balls. If a close-up of that event is recorded with a camera and played in reverse, it can still be represented by the same equation. Moreover, it is not possible to distinguish from the recording if it has been doctored. Both versions look plausible. It would appear that the billiard balls defy the intuitive sense of time.

However, imagine recording a cue ball breaking the pyramid, the billiard balls scattering in all directions. In that case, it is easy to distinguish the real-life scenario from reverse playback. What makes the latter look so absurd is our intuitive understanding of the second law of thermodynamics—an isolated system either remains static or evolves toward a state of chaos rather than order.

Most other laws of physics do not prevent rolling billiard balls from assembling into a pyramid, infused tea from flowing back into the tea bag, or a volcano from "erupting" in reverse. But these phenomena are not observed, because they would require an isolated system to assume a more ordered state without any outside intervention, which runs contrary to the second law. The nature of that law has not been explained in full detail, but researchers have made great headway in understanding the basic principles behind it.

Spontaneous time reversal

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 Schrödinger'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.

The four stages of the actual experiment on a quantum computer mirror the stages of the thought experiment involving an electron in space and the imaginary analogy with billiard balls. Each of the three systems initially evolves from order toward chaos, but then a perfectly timed external disturbance reverses this process. Credit: @tsarcyanide/MIPT

"However, Schrödinger'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.

Large-scale phenomena involving billiard balls and volcanoes obviously unfold on much greater timescales and feature an astounding number of electrons and other particles. This explains why we do not observe old people growing younger or an ink blot separating from the paper.

Reversing time on demand

The researchers then attempted to reverse time in a four-stage experiment. Instead of an electron, they observed the state of a quantum computer made of two and later three basic elements called superconducting qubits.

Stage 1: Order. Each qubit is initialized in the ground state, denoted as zero. This highly ordered configuration corresponds to an electron localized in a small region, or a rack of billiard balls before the break.

Stage 2: Degradation. The order is lost. Just like the electron is smeared out over an increasingly large region of space, or the rack is broken on the pool table, the state of the qubits becomes an ever more complex changing pattern of zeros and ones. This is achieved by briefly launching the evolution program on the quantum computer. Actually, a similar degradation would occur by itself due to interactions with the environment. However, the controlled program of autonomous evolution will enable the last stage of the experiment.

Stage 3: Time reversal. A special program modifies the state of the quantum computer in such a way that it would then evolve "backwards," from chaos toward order. This operation is akin to the random microwave background fluctuation in the case of the electron, but this time, it is deliberately induced. An obviously far-fetched analogy for the billiards example would be someone giving the table a perfectly calculated kick.

Stage 4: Regeneration. The evolution program from the second stage is launched again. Provided that the "kick" has been delivered successfully, the program does not result in more chaos but rather rewinds the state of the qubits back into the past, the way a smeared electron would be localized or the billiard balls would retrace their trajectories in reverse playback, eventually forming a triangle.

The researchers found that in 85 percent of the cases, the two-qubit quantum computer returned back into the initial state. 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.

Interestingly, the time reversal algorithm itself could prove useful for making quantum computers more precise. "Our algorithm could be updated and used to test programs written for quantum computers and eliminate noise and errors," Lebedev explained.

More information: G. B. Lesovik et al. Arrow of time and its reversal on the IBM quantum computer, Scientific Reports (2019). Journal information: Scientific Reports G. B. Lesovik et al. Arrow of time and its reversal on the IBM quantum computer,(2019). DOI: 10.1038/s41598-019-40765-6</s>Scientists have reversed the direction of time with a quantum computer.

The breakthrough study seems to contradict basic laws of physics and could alter our understanding of the processes governing the universe.

In a development that also represents a major advance in our understanding of quantum computers, by using electrons and the strange world of quantum mechanics researchers were able to turn back time in an experiment that can be likened to causing a broken rack of pool balls to go back into place.

We’ll tell you what’s true. You can form your own view. From 15p €0.18 $0.18 USD 0.27 a day, more exclusives, analysis and extras.

Anyone watching the computer would see the event as if time had turned backwards.

The researchers – from the Moscow Institute of Physics and Technology (MIPT) and helped by colleagues in Switzerland and the US – expect the technique to improve, becoming more reliable and precise with time.

Lead researcher Dr Gordey Lesovik, who heads the Laboratory of the Physics of Quantum Information at the MIPT, said: “We have artificially created a state that evolves in a direction opposite to that of the thermodynamic arrow of time.”

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The “time machine” described in the journal Scientific Reports consists of a rudimentary quantum computer made up of electron “qubits”.

A qubit is a unit of information described by a “one”, a “zero”, or a mixed “superposition” of both states.

In the experiment, an “evolution program” was launched which caused the qubits to become an increasingly complex changing pattern of zeros and ones.

During this process, order was lost – just as it is when the pool balls are struck and scattered with a cue.

But then another program modified the state of the quantum computer in such a way that it evolved “backwards”, from chaos to order.

It meant the state of the qubits was rewound back to its original starting point.

Most laws of physics work both ways, in the future and the past. If you see a video of a pool ball knocking into another one, for instance, and then reverse that same video, the physical processes would both make sense and it would be impossible at the level of physics to know which way around would be correct.

But the universe does have one rule that goes only in one way: the second law of thermodynamics, which describes the progression from order to disorder.

If you saw a video of someone breaking a perfectly arranged triangle of pool balls into a mess, for instance, then watching that backwards would obviously look nonsensical.

The new experiment is like giving the pool table such a perfectly calculated kick that the balls rolled back into an orderly pyramid.

The scientists found that, working with just two qubits, “time reversal” was achieved with a success rate of 85 per cent. When three qubits were involved more errors occurred, resulting in a 50 per cent success rate.

The error rate is expected to drop as scientists improve the sophistication of the devices used, the researchers behind the discovery said.

The experiment could have a practical application in the development of quantum computers, the scientists said.

“Our algorithm could be updated and used to test programs written for quantum computers and eliminate noise and errors,” said Dr Lesovik.</s>An international team of scientists led by researchers at the Moscow Institute of Physics and Technology demonstrated the possibility of time reversal in a development that contradicts the basic laws of physics, Newsweek reported on Wednesday. The researchers were assisted by colleagues in Switzerland and the United States.

Lead researcher Dr Gordey Lesovik, who heads the Laboratory of the Physics of Quantum Information at the Moscow Institute of Physics and Technology, said, “We have artificially created a state that evolves in a direction opposite to that of the thermodynamic arrow of time.”

In a study published in the journal Scientific Reports on March 13, the scientists experimentally showcased time reversal by sending a qubit from a more complex state to a simpler one using an algorithm on an IBM quantum computer. A qubit, or quantum bit, is the basic unit of quantum information. It is the quantum version of a computer binary bit, which can be a one or a zero.

The quantum physicists decided to check if time could spontaneously reverse itself, at least for an individual particle, and for a tiny fraction of a second. As a result, they examined a single electron in empty interstellar space.

“Suppose the electron is localised when we begin observing it. This means that we are pretty sure about its position in space,” said the study’s co-author Andrey Lebedev from the Moscow Institute of Physics and Technology. “The laws of quantum mechanics prevent us from knowing it with absolute precision, but we can outline a small region where the electron is localised.”

The researchers attempted to calculate the probability of observing an electron over a fraction of a second spontaneously localising into its recent past. Later, they made the same attempt to reverse time using qubits. They employed a programme to convert the qubits into a more complex pattern of ones and zeros, and then used another programme to bring them back to their original state. This successfully caused the qubits to evolve backwards, from chaos towards order.

The team found that in 85% of the cases, the two-qubit quantum computer returned back to the initial state. However, more errors occurred when a third qubit was introduced, with the success rate falling to around 50%.

“Such an unfortunate growth of the complexity explains why do we not observe such time-reversed objects in nature,” said Lebedev. “The probability of a spontaneous appearance of a time-reversed object [particle of a system of particles] is negligible.”</s>Web Desk: You have already witnessed in the movies that how time travels and how altering the timeline can cause chaos, implode the universe.

Scientists have just used a quantum computer to effectively reserve time. They haven’t swung reality backwards or anything, but they have demonstrated a phenomenon that goes against the laws of physics.

Researchers from the Moscow Institute of Physics and Technology along with colleagues from Switzerland and the US, built their “time machine” using a fairly rudimentary quantum computer. In regular computers, information is stored in bits, which is represented as a 0 or a 1. In quantum computing, qubits can be 0, 1, or even both simultaneously.

They designed an experiment called an “evolution program” that basically causes these ordered qubits to change into increasingly complex patterns of zeroes and ones. However, they also had another program designed to modify the state of the quantum computer in such a way that the experiment evolved backwards.

Basically, the chaos of the qubits rewound to their starting states and became ordered once more. To someone watching, it would have been like time rewinding.

That’s in direct violation of the second law of thermodynamics, which governs how order progresses to chaos. It’s like how a pile of dead leaves would scatter if the wind blew at it. If you recorded a video of that and played it backward, it would look completely strange.

And yet, that’s exactly what this experiment achieved, by calculating the exact kind of gust needed to blow scattered leaves into a neat pile.

“We have artificially created a state that evolves in a direction opposite to that of the thermodynamic arrow of time,” said Dr Gordey Lesovik, lead researcher at the Laboratory of the Physics of Quantum Information at the Moscow Institute of Physics & Technology (MIPT).

Their system was able to perform this metaphorical time reversal with a success rate of 85 percent when using two qubits. When working with three however, it had a 50 percent error rate. However, the researchers believe this error rate isn’t insurmountable, they just need more sophisticated hardware.</s>March 13 (UPI) -- Physicists in Russia have turned back time using a quantum computer.

For some time, researchers at the Moscow Institute of Physics and Technology have been working to prove the second law of thermodynamics can be violated.

"That law is closely related to the notion of the arrow of time that posits the one-way direction of time from the past to the future," lead researcher Gordey Lesovik said in a news release.

Lesovik and his colleagues have already published two papers on the subject. For the latest study, scientists teamed with physicists in the United States and Switzerland to construct a quantum computer capable of violating the second law.

"We have artificially created a state that evolves in a direction opposite to that of the thermodynamic arrow of time," Lesovik said.

The second law of thermodynamics posits that an isolated system can only remain static or evolve toward a state of chaos. If a video of a cue ball colliding with a pyramid of billiard balls was played backward and forward, the viewer would quickly be able to discern which direction revealed the actual sequence of events. The viewer intuitively understands the second law of thermodynamics.

There are no physical laws that explicitly prevent the violation of the second law, but violations have remained unobserved.

To better understand the odds of the second law being violated, quantum physicists analyzed the behavior individual particles.

"Suppose the electron is localized when we begin observing it," said Andrey Lebedev, who works at both MIPT and ETH Zurich. "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."

Schrödinger's equation describes the evolution of a particle's electron state. The region of space containing the electron quickly expands. Chaos increases as systems scale.

"However, Schrödinger's equation is reversible," said Valerii Vinokur, a researcher at the Argonne National Laboratory in the United States. "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."

Researchers crunched the numbers and found that if 10 billion freshly localized electrons were observed every second for the entirety of the universe's lifetime, 13.7 billion years, only one particle would be observed reversing time -- spontaneously localizing against the arrow of time.

Next, scientists attempted to manufacture a violation of the second law of thermodynamics. They built a quantum computer with two and three superconducting qubits. Physicists used the quantum computer to conduct a four-stage experiment.

Stage one features an ordered state, with each qubit grounded at zero, like a single electron confined to a small localized region. During the second stage, order is lost. Scientists used an evolution program on the quantum computer to trigger the degradation of order, causing the qubits to begin assuming an increasingly complex pattern of zeros and ones, like an electron getting smeared out across a larger and larger region of space.

For stage three, scientists used another program to reverse time, causing the qubits to evolve from chaos to order -- to reground themselves at zero. For stage four, the evolution program is relaunched from the second stage, causing the qubits to reverse time and revert to their earlier state.

When scientists used a two-qubit computer to conduct the four stage experiment, they observed qubits moving from chaos to order every time. When they introduced a third qubit, the computer produced more errors, and the qubits were able to reverse time only half of the time.

Researchers suggest their findings -- published this week in the journal Scientific Reports -- could be used to improve the precision of quantum devices.

"Our algorithm could be updated and used to test programs written for quantum computers and eliminate noise and errors," Lebedev said.</s>An international team of scientists claims to have reversed time with the help of a quantum computer.

By using electrons and quantum mechanics researchers claim they were able to turn back time in an experiment likened to causing a broken rack of pool balls to roll back into place.

The experiment used quantum computer programs to ‘rewind’ scattered quantum bits or qubits back to their starting points.

Researchers from the Moscow Institute of Physics and Technology, helped by colleagues in Switzerland and the U.S., expect the technique to become more efficient.

“Our findings break ground for investigations of the time reversal and the backward time flow in real quantum systems,” the scientists wrote in their conclusion to ‘Arrow of time and its reversal on IBM Quantum Computer.’

“Another fundamental question is whether it is possible at all to design a quantum algorithm that would perform time-reversal more efficiently.”

The scientists found that, working with just two qubits, time reversal was achieved with a success rate of 85 per cent.

When three qubits were involved more errors occurred and the experiment was successful just half the time.</s>We all mark days with clocks and calendars, but perhaps no timepiece is more immediate than a mirror. The changes we notice over the years vividly illustrate science's "arrow of time" -- the likely progression from order to disorder. We cannot reverse this arrow any more than we can erase all our wrinkles or restore a shattered teacup to its original form.

Or can we?

An international team of scientists led by the U.S. Department of Energy's (DOE) Argonne National Laboratory explored this question in a first-of-its-kind experiment, managing to return a computer briefly to the past. The results, published March 13 in the journal Scientific Reports, suggest new paths for exploring the backward flow of time in quantum systems. They also open new possibilities for quantum computer program testing and error correction.

To achieve the time reversal, the research team developed an algorithm for IBM's public quantum computer that simulates the scattering of a particle. In classical physics, this might appear as a billiard ball struck by a cue, traveling in a line. But in the quantum world, one scattered particle takes on a fractured quality, spreading in multiple directions. To reverse its quantum evolution is like reversing the rings created when a stone is thrown into a pond.

In nature, restoring this particle back to its original state -- in essence, putting the broken teacup back together -- is impossible.

The main problem is that you would need a "supersystem," or external force, to manipulate the particle's quantum waves at every point. But, the researchers note, the timeline required for this supersystem to spontaneously appear and properly manipulate the quantum waves would extend longer than that of the universe itself.

Undeterred, the team set out to determine how this complexity might be overcome, at least in principle. Their algorithm simulated an electron scattering by a two-level quantum system, "impersonated" by a quantum computer qubit -- the basic unit of quantum information -- and its related evolution in time. The electron goes from a localized, or "seen," state, to a scattered one. Then the algorithm throws the process in reverse, and the particle returns to its initial state -- in other words, it moves back in time, if only by a tiny fraction of a second.

Given that quantum mechanics is governed by probability rather than certainty, the odds for achieving this time-travel feat were pretty good: The algorithm delivered the same result 85 percent of the time in a two-qubit quantum computer.

"We did what was considered impossible before," said Argonne senior scientist Valerii Vinokur, who led the research.

The result deepens our understanding of how the second law of thermodynamics -- that a system will always move from order to entropy and not the other way around -- acts in the quantum world. The researchers demonstrated in previous work that, by teleportating information, a local violation of the second law was possible in a quantum system separated into remote parts that could balance each other out.

"The results also give a nod to the idea that irreversibility results from measurement, highlighting the role that the concept of "measurement" plays in the very foundation of quantum physics," said article coauthor Gordey Lesovik of the Moscow Institute of Physics and Technology.

This is the same notion Austrian physicist Erwin Schrödinger captured with his famous thought experiment, in which a cat sealed in a box might remain both dead and alive until its status is monitored somehow. The researchers suspended their particle in this superposition, or form of quantum limbo, by limiting their measurements.

"This was the essential part of our algorithm," Vinokur said. "We measured the state of the system in the very beginning and at the very end, but did not interfere in the middle."

The finding may eventually enable better methods of error correction on quantum computers, where accumulated glitches generate heat and beget new ones. A quantum computer able to effectively jump back and clean up errors as it works could operate far more efficiently.

"At this moment, it's very hard to imagine all the implications this can have," Vinokur said. "I am optimistic, and I believe that it will be many."

The study also begs the question, can the researchers now figure out a way to make older folks young again? "Maybe," Vinokur jokes, "with the proper funding."

The work was done by international team including researchers from the Moscow Institute of Physics and Technology (Gordey Lesovik, Andrey Lebedev, Mikhail Suslov), ETH Zurich (Andrey Lebedev) and Argonne National Laboratory, U.S. (Valerii Vinokur, Ivan Sadovskyy).

Funding for this research was provided by the DOE Office of Science and Strategic Partnership Projects (Swiss National Foundation and the Foundation for the Advancement of Theoretical Physics "BASIS").

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation's first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America's scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy's Office of Science.

The U.S. Department of Energy's Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit the Office of Science website.</s>Move over, TARDIS: Scientists just reported that they were able to turn back time by using a quantum computer.

A team of scientists from the Moscow Institute of Physics and Technology, the U.S., and Switzerland, published their findings in Scientific Reports, and said they reversed time by a fraction of a second on an IBM quantum computer, New York Daily News reported. In the report, the scientists also determined the “probability that an electron in empty interstellar space will randomly travel back into its recent past,” Phys.org noted.

According to the report, finding the origin of the “arrow of time” is still a major scientific challenge. The scientists’ experiment challenged the second law of thermodynamics, which dictates the direction of events from the past to the future and involves the transition of energy within a system from usable to unusable, The Daily Mail reported.

Most laws of physics do not make a distinction between the past and future, but the scientists claim that their experiment, which involved “reversing time,” showed that these laws can be violated. For their research, scientists were curious if individual particles could impulsively reverse themselves.

To put this concept to the test, the scientists formulated two separate hypothesis: Time reversal would require supersystem manipulation to occur and “in most cases,” would not likely take place in nature. Second, if a supersystem were to “emerge for some specific situation,” a time reversal would need time that “exceeds the universal lifetime” to work.

The scientists tried to accomplish time reversal for a scattered electron with the help of an IBM quantum computer. For the experiment, the scientists used an “evolution program” that would impact “qubits,” also known as quantum bits. A quantum bit is the “fundamental unit of information in a quantum computer, capable of existing in two states, 0 and 1, at the same time or at a different time,” according to Dictionary.com.

Here’s how it works: Following the launch of the evolution program, the particles would move into a changing pattern of zeros and ones. Following this scattering, a program would alter the computer’s state, enabling it to go backwards to its original state. Next, the evolution pattern would be kickstarted from the second state again and rewind the qubits to their original state and the past.

According to the team, in 85 percent of cases, the two-qubit quantum computer returned back into its original state. When three qubits were involved in testing, more errors occurred, and resulted in an approximately 50 percent success rate. The scientists said the error rate is anticipated to drop as more devices are designed. With this experiment, time reversal can help make quantum computers more accurate in the future.</s>The breakthrough came as they were able to go a fraction of a second into the past. It was discovered by researchers from the Moscow Institute of Physics and Technology (MIPT) who teamed up with experts from the US and Switzerland. They discovered the time travel as they checked if time could spontaneously reverse itself for an individual particle and for a tiny fraction of a second.

The research was also able to calculate the probability that an electron in empty interstellar space will spontaneously travel back into its recent past according to the research published in the journal Scientific Reports. Lead author Gordey Lesovik, head of the Laboratory of the Physics of Quantum Information Technology at MIPT, said: "This is one in a series of papers on the possibility of violating the second law of thermodynamics. “That law is closely related to the notion of the arrow of time that posits the one-way direction of time from the past to the future. "We began by describing a so-called local perpetual motion machine of the second kind. READ MORE: Time travel PROOF? ‘Time traveller’ from 2030 warns Mexico SURRENDERS border to USA

“Then, in December, we published a paper that discusses the violation of the second law via a device called a Maxwell's demon. "The most recent paper approaches the same problem from a third angle. We have artificially created a state that evolves in a direction opposite to that of the thermodynamic arrow of time." Study co-author Andrey Lebedev from MIPT and ETH Zurich said: "Suppose the electron is localised 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 localised.”The discovery contradicts the laws of physics, which suggests that time is linear and can only travel in one direction - forward. However, the quantum computer can be described as a semi-time machine and has defied the second law of thermodynamics, which is the arrow of time. By using the computer, researchers were able to unscramble a set of electrons which was akin to pool balls on a table going back in to a starting triangle-formation.</s>Although many Americans turned their clocks forward an hour over the weekend, these scientists reported they were able to turn back time.

According to a report published in the journal Scientific Reports on Tuesday, a team of physicists was able to reverse time on an IBM quantum computer by a fraction of a second.

The experiment was done by a team of scientists from the Moscow Institute of Physics and Technology, the U.S. and Switzerland.

“Uncovering the origin of the ‘arrow of time’ remains a fundamental scientific challenge,” the report said.

The experiment challenged the second law of thermodynamics — which states “as energy is transferred or transformed, more and more of it is wasted. It also states that “there is a natural tendency of any isolated system to degenerate into a more disordered state,” as explained by Live Science.

A majority of the laws of physics — like the second, primarily considered in the experiment — do not differentiate between the past and future, as explained in Science X. However, the scientists said the experiment where they “reversed time” show these laws can be violated.

For example, if two pool balls colliding was recorded, the same law would explain the balls colliding and rebounding off one another if the video was played normally and in reverse.

More at the NY Daily News
A team of physicists at the Moscow Institute of Physics and Technology, assisted by colleagues in Switzerland and the United States, successfully returns the state of a quantum computer a fraction of a second into the past.