Sign-preserving operations on two-dimensional grids
Zohar Ringel, Dmitry L. Kovrizhin / Science advances
In some quantum systems, the sign problem is fundamentally unsolvable. This means that they cannot be efficiently simulated on classical computers. Two physicists, including one from the Kurchatov Institute, have shown that such a problem arises from gravitational anomalies in systems with bosonic degrees of freedom, such as the fractional Hall effect. Article published in the journal Science Advances.
It is traditionally believed that all problems that can be efficiently solved on a classical computer can be solved just as efficiently on a quantum computer, but not vice versa. For example, effective classical simulators have not yet been found for many systems with bosonic degrees of freedom that arise naturally when studying models of interacting quantum many-body systems (quantum many-body systems). In the new work, scientists have shown that the absence of such simulations is due not to a lack of ingenuity of researchers, but to the fundamental impossibility of their existence.
The authors of the article note that proving the impossibility of classical simulations in general is an ill-defined problem. Therefore, they showed that fundamental problems arise when using the most common method of numerical research in the field, the quantum Monte Carlo method. The main tool of this method is the generating functional (partition function , should not be confused with the partition function from statistical mechanics). Knowing it, with the help of differentiation it is easy to find the correlation functions of the system. However, it turns out that the calculation of the functional is not always possible due to the sign problem when the phases of the integrands change rapidly.
The basic idea behind the physicist's proof is based on the concept of anomalies. Anomalies are peculiar effects that occur when the symmetry that is present at the level of classical field theory is violated at the level of quantum field theory. Both the usual Hall effect and the temperature (Rigi-Leduc effect, thermal Hall effect) can be understood in terms of anomalies - charge and gravitational (gravitational anomaly, the adjective "gravitational" appears due to the general covariance of the theory, and not due to gravitational effects ) respectively.
Often, when associating anomalous theories with static gauge fields, one finds that the flows of the gauge field lead to the appearance of complex phase factors in the generating functional. This makes it impossible to construct a generating functional without a sign problem, in which complex phases are forbidden by definition. However, this is not always the case, and there are various counterexamples. The subtlety lies in the fact that complex phases may arise not in the original theory, but as a result of the addition of a gauge field flux.
The proof that for the classical generating functional in the 2 + 1-dimensional theory of the bosonic fractional quantum Hall effect on a plane or on a torus it is impossible to get rid of the sign problem, physicists carried out in three steps. First, they established that gravitational anomalies cause chiral excitations at the boundary of the volume under study. They then showed that the existence of a spatially isolated chiral channel in this theory forbidden provided that the translation operator and the Perron-Frobenius operator are non-negative. At the same time, the existence of an unsigned generating functional (that is, one in which there is no sign problem) leads to the non-negativity of these operators. Thus, the obtained contradiction testifies to the impossibility of circumventing the sign problem in this theory.
Physicists then looked at frustrated quantum systems, in which states similar to those arising from the fractional Hall effect appear due to spontaneous breaking of time symmetry (time-reversal symmetry). For example, such systems include Kagome quantum antiferromagnets. In general, the above considerations apply to them, although some additional microscopic assumptions need to be made.
Thus, scientists have shown that for a wide class of quantum systems, when calculating using the quantum Monte Carlo method, it is fundamentally impossible to get rid of the sign problem. This means that such systems cannot be effectively simulated using conventional, classical computers. Perhaps this obstacle can be overcome in the future with the help of quantum computers.
Recently, we talked about how physicists solved the sign problem with the help of a neural network in the 1 + 1-dimensional Thirring model.
Dmitry Trunin
When Tesla and SpaceX founder Elon Musk made a fuss during Code Code 2016, declaring a high probability that humanity exists inside an artificial, virtual universe, the public reacted very strongly. Fans of The Matrix were delighted, while others were horrified. Alas, new research has shown that there is no supercomputer supporting the existence of millions of people in a simulation of reality, and there cannot be. It's not about philosophy or a special way of looking at life - just the bare facts.
Is The Matrix a lie?
A recent study by theoretical physicists at the University of Oxford, which was published in the journal Scientific Advances just last week, finally confirms that life and reality are not products of computer simulations. Researchers led by Zohar Ringel and Dmitry Kovrizhi came to this conclusion after noticing a new connection between gravitational anomalies and the complexity of quantum computing.
Proponents of a simulated universe theory, such as Musk himself and the popular astrophysicist Neil Degrasse Tyson, often point to the ever-increasing capabilities of modern computer systems as evidence that reality can be emulated. In concept simulated universe, which became popular thanks to the British philosopher Nick Bostrom back in 2003, it is likely that in the hypothetical future, highly developed civilizations will develop realistic virtual simulations that create the illusion of past eras. For us, this “past” is quite real, and it would be appropriate to compare the simulations themselves with computer games that also recreate interactive pictures of ancient civilizations.
However, according to a new study, the creation of such a complex simulation is seen by scientists as impossible even in theory. The reason is simple: in the part of the universe known to us, there are simply no elements capable of forming mechanisms of such high computational power to model something so colossal.
Reality or Simulation: Physics vs. Fiction
The Oxford team asked the question: is it possible to build a computer simulation powerful and complex enough to show the quantum effects of many physical bodies? For those who are poorly versed in quantum physics, we explain that in our Universe the number of interactions of quantums with each other is so large that it simply defies description. Specifically, the scientists tested an anomaly known as the quantum Hall effect using the Monte Carlo method, a computational technique that uses random sampling to study complex quantum systems.
The researchers found that in order to accurately model the quantum phenomena that occur in matter, the system must be extremely complex. This complexity increased exponentially as the number of particles needed to model the full picture increased. As a result, it became clear that this impossible purely physically - and this despite the fact that physicists included in their calculations only a part of the world known to mankind, and not the entire Universe as a whole. Scientists emphasized that in order to store complete information even about a couple of hundred electrons, a computer memory with more than is available in the world is needed. “However, the possibility cannot be ruled out that some physical property (meaning the characteristic of a hypothetical simulation) specifically creates an obstacle to efficient classical simulation of many-particle quantum systems,” they write.
The physical limitation demonstrated by the researchers is quite enough to nullify all hypotheses about the superintelligence, forcing people to live in a huge computer simulation. Contrary to the statements of Musk or Tyson, the achievements of mankind, apparently, are still the merit of the people themselves and their painstaking work, and not a pre-written program that leads the development of mankind along a course set from above.
However, it cannot be argued that a person has known the Universe so well to make such statements with 100% certainty. The assumption of probabilities, even fantastic ones, is one of the qualities due to which people make more and more breakthroughs in science, pushing the border of the “impossible” further and further over and over again.
The hypothesis of a computer simulation of our universe was put forward in 2003 by the British philosopher Nick Bostrom, but has already received its followers in the person of Neil deGrasse Tyson and Elon Musk, who said that the probability of the hypothesis is almost 100%. It is based on the idea that everything that exists in our universe is the product of a simulation, like the experiments carried out by machines from the Matrix trilogy.
Simulation theory
The theory suggests that, given enough computers with great computing power, it becomes possible to simulate in detail the entire world, which will be so believable that its inhabitants will be conscious and intelligent.
Based on these ideas, we can assume: what prevents us from already living in a computer simulation? Perhaps a more advanced civilization is conducting a similar experiment, having received the necessary technologies, and our whole world is a simulation?
Many physicists and metaphysicians have already created convincing arguments in favor of the idea, referring to various mathematical and logical anomalies. Based on these arguments, one can assume the existence of a space computer model.
Mathematical refutation of the idea
However, two physicists from Oxford and the Hebrew University in Jerusalem, Zohar Ringel and Dmitry Kovrizhin, proved the impossibility of such a theory. They published their findings in the journal Science Advances.
By modeling a quantum system, Ringel and Kovrizhin found that simulating just a few quantum particles would require huge computational resources, which, due to the nature of quantum physics, would increase exponentially with the number of simulated quanta.
A terabyte of RAM is required to store a matrix describing the behavior of 20 spins of quantum particles. Extrapolating this data over just a few hundred spins, we get that to create a computer with this amount of memory, it would take more atoms than the total number of atoms in the universe.
In other words, given the complexity of the quantum world that we observe, it can be proven that any proposed computer simulation of the universe will fail.
Or maybe it's a simulation?
On the other hand, continuing philosophical reasoning, a person will quickly come to the question: “Is it possible that more advanced civilizations deliberately put this complexity of the quantum world into the simulator in order to lead us astray?” Dmitry Kovrizhin answers this:
This is an interesting philosophical question. But it is outside the scope of physics, so I would prefer not to comment on it.
Scientists at Oxford University disproved the theory that the world exists in a computer simulation. Zohar Ringel and Dmitry Kovrizhin worked on the study.
Our species is much older than scientists previously thought Scientists studied the DNA of fossils that were found in Morocco, and came to the conclusion that the species Homo sapiens appeared in the period from 260 to 350,000 years ago. This is reported by the NY Post. Previously, the oldest known fossils of a human of our species were believed to be fossils from Ethiopia at the age of about 200 thousand years.
Scientists have refuted that a computer can create such a large number of simultaneous actions.
Ringel and Kovrizhin calculated that just storing information about a few hundred electrons would require computer memory, which would require more atoms than there are in the universe.
The study proved that it is impossible to simulate such a system on a classical computer, but it is likely that quantum computers will someday be able to cope with this.
American businessman and inventor Elon Musk is one of the adherents of the matrix theory. He believes that humanity lives in a simulation of the real world.
As Musk argued, video games are developing very quickly and people are already creating another reality through them and can control it. Therefore, the probability that humanity lives in a basic reality is one in billions.
See also: Nobel Prize in Physics awarded for discovery of gravitational waves
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Our species is much older than scientists previously thought Scientists studied the DNA of fossils that were found in Morocco, and came to the conclusion that the species Homo sapiens appeared in the period from 260 to 350,000 years ago. This is reported by the NY Post. Previously, the oldest known fossils of a human of our species were believed to be fossils from Ethiopia at the age of about 200 thousand years.
Nobel Prize in Medicine awarded to 'biological clock'
US scientists Jeffrey Hall, Michael Rosbash and Michael Young became the winners of the award Today in Stockholm the names of the Nobel Prize winners were announced. This is reported by the Nobel Committee on Twitter. The award was given to US scientists Jeffrey Hall, Michael Rosbash and Michael Young for discovering the molecular mechanisms that control circadian rhythms. Circadian rhythms help control sleep, nutrition, hormone production, and blood pressure.
Nobel Prize in Physics awarded for the discovery of gravitational waves
The Nobel Prize in Physics in 2017 was awarded to US scientists Rainer Weiss, Kip Thorne and Barry Barish Today, the Nobel Prize in Physics was received by US scientists Rainer Weiss, Barry Barish and Kip Thorne for detecting gravitational waves with the LIGO detector. This is reported by the Nobel Committee on Twitter. Last year, the Nobel Prize in Physics went to David Thouless, Duncan Haldane and Michael Kosterlitz "for their theoretical discoveries in topological phase transitions and topological phases of matter."
Ministry of Natural Resources initiates studies of the elk population in Ukraine
According to Semerak, if the information about the threats to the existence of moose is confirmed, the agency will return to the initiated dialogue on the ban on hunting. The Ministry of Ecology and Natural Resources will initiate scientific research on the European moose population in Ukraine. This was stated by the Minister of Ecology and Natural Resources Ostap Semerak during a joint press conference of the Ministry of Natural Resources and the Ministry of Agrarian Policy, the government portal reports. "The discussion about the ban on elk hunting is not over.
Turkish archaeologists claim to have found the tomb of Santa Claus
An intact tomb was found in the underground rooms of the Church of St. Nicholas near the Turkish city of Demre Turkish archaeologists reported that they supposedly found the burial place of St. Nicholas the Wonderworker, but so far they cannot get to his remains. It is reported by the Air Force. It is reported that the intact tomb was found in the underground premises of the Church of St. Nicholas in the Turkish city of Demre, in the southwestern province of Antalya.
Scientists have found a way to destroy HIV-infected cells
KYIV. October 13th. UNN. Modified DNA immune cells, which were invented by American molecular biologists, began to recognize cells infected with HIV and destroy them before the virus begins to destroy the immune system. Scientists have successfully conducted studies on mice, reports UNN with reference to PLoS Pathogens. These tronsgenic T-cells can protect the body of animals from the recurrence of the infection after the antiretroviral drugs are stopped. read also: 136 thousand people are HIV-infected in Ukraine
Scorpions are able to "tune" the poison for defense and attack
Scientists have come to the conclusion that prolonged exposure to appropriate environmental conditions leads to a change in the composition of the poison in scorpions. Scorpions are attacked by animals that are usually much larger than them in size, and the victims of the scorpions themselves are mainly smaller insects. Therefore, scorpions have learned to fine-tune the poisonous mixture to their current needs, according to Naked Science.
Scientists measure the Milky Way
KYIV. October 14. UNN. According to the latest measurements, the size of the Milky Way galaxy is 66.5 thousand light years. Writes about this edition of Science, reports UNN. It is noted that previously it was impossible, since direct measurements of distances to astronomical sources rely on parallax, which can usually be measured only relative to neighboring objects. The long side of the Milky Way could not be accurately measured because the parallax is very small and interstellar dust blocks optical light from these regions.
Scientists: Hallucinogenic mushrooms can help with depression
Psilocybin suppresses the amygdala, which is largely responsible for emotions such as fear and anxiety. Psilocybin, a substance found in hallucinogenic mushrooms, can "rewire" the brain of a person with severe chronic depression, raising hopes for a future course of treatment. These are the conclusions of a study conducted by a group of scientists at Imperial College London. In a small study, 19 patients were given a single dose of psilocybin.
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Physicists proved the impossibility of the existence of the Matrix Anonymous 03/10/17 Tue 21:26:33 # 1535110
Scientists have proved the impossibility of the matrix - www.vladtime.ru
Scientists from Russia and Israel proved the impossibility of the matrix, experts shared the results of their research with the public. This was told by journalists and published a detailed description of the process in Science Advances.
news/ - Physicists prove the impossibility of existence - 2ch.hk
Physicists proved the impossibility of the existence of the Matrix Anonymous 04/10/17 Wed 02:46:04 No. 1536255
We live in the Matrix - and here are 15 proofs! - fishki.net
Yes, and many other businessmen, scientists, philosophers believe that this is possible - with a probability of 20-50%. The most convincing argument in favor of our existence in the real Matrix is that 18 photographs proving that the matrix exists.
Physicists have proved the impossibility of life in the matrix
Chronicle of events » Incredible » Physicists have proved the impossibility of life in the matrix. Scientists are trying to find an answer to a hypothetical theory regarding the existence of a parallel world, as an alternative universe.
Scientists have disproved the theory about the unreality of our universe
However, two physicists from Oxford and the Hebrew University in Jerusalem, Zohar Ringel and Dmitry Kovrizhin, proved the impossibility of the existence of such a matrix. To store a matrix describing the behavior of 20 spins of quantum particles, a terabyte of RAM is required.
10 signs that we live in the "matrix" - computer - hi-news.ru
The Matrix offers an example of deja vu - when something seems inexplicably familiar. Scientists suggest that someone may have already done this and created our world. Of course, this postulate, like the existence of God, cannot be proved or disproved, but it is open to discuss
The impossibility of the matrix is proved: Science: Science and technology - lenta.ru
Physicists from Israel and Russia have demonstrated that humanity does not live in a matrix. As the number of particles increased in the simulation, the scientists found that the required
Science: Scientists prove the impossibility of the matrix - yodda.ru
Scientists from Russia and Israel proved the impossibility of the matrix, experts shared the results of their research with the public. British scientists have proven that the soul exists Scientists were able to scientifically prove the existence of the soul.
Not a single Neo was hurt: Physicists from Israel and Russia proved - www.yaplakal.com
The study suggests the impossibility of creating the illusion of reality. What kind of scientists are these who have neither a VR helmet nor LSD .. The fact that these scientists do not have such computing power does not cancel the existence of the matrix.
Scientists have tested the possibility that humanity | Gamebomb.ru - gamebomb.ru
Why do scientists reject the existence of the Matrix, only based on the alleged impossibility of hardware calculations of this magnitude? Why, Mr. Anderson? Why are you trying to prove that everything around is not a matrix? Like! Lvl 4.
Scientists have proved the impossibility of the matrix
Physicists from Russia and Israel have proven that humanity cannot live in the matrix. During the experiment, scientists simulated a quantum system of the behavior of gas particles using the computing power of the university, while gradually adding to the model
Physicists have proved the impossibility of the existence of the matrix
Physicists agreed that their study suggests the impossibility of creating the illusion of reality. Thus, the theory of SpaceX CEO Elon Musk about the presence of humanity in the matrix is erroneous. Previously, scientists have shown the existence
Scientists have proved the impossibility of the matrix - news.ivest.kz
ivest.kz » News » News feeds » tengrinews.kz » Scientists proved the impossibility of the matrix. Physicists from Israel and Russia have demonstrated that humanity does not live in a matrix, reports Lenta.ru.
Physicists have proved the impossibility of life in the matrix?: Can - www.vladtime.ru
The new work of Ringel and Kovrizhin proved that such simulations cannot exist at all, not because the researchers are not inventive, but because of a principled non-scientist from Kaliningrad put forward the version that humanity exists in the matrix.
Scientists have proved the impossibility of the matrix | Tengrinews - tengrinews.kz
Scientists proved the impossibility of the matrix - events in the scientific field in Kazakhstan and around the world. Physicists from Israel and Russia have demonstrated that humanity does not live in a matrix, reports Lenta.ru.
The Matrix hypothesis: now everything is serious
Scientists note that for us the possible existence of the Matrix does not fundamentally change anything in the approach to the perception of the world. So, do the above arguments prove that our universe is a simulation? Obviously not.
3 EXPERIMENTS PROVING WE ARE LIVE - www.youtube.com
3 EXPERIMENTS PROVING THAT WE LIVE IN THE "MATRIX" OF OUR ILLUSIONS. EVIDENCE OF THE VIRTUALITY OF OUR WORLD - Duration: 22:54. Top Five 3,695,417 views.
Wall | VKontakte - vk.com
Wall | VKontakte - vk.com
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Is it really possible to have a moving physical object with zero energy? From the point of view of common sense, this is impossible, because the movement itself is kinetic energy. This obvious physical fact was challenged by the concept of quantum space-time crystals, which was proposed in 2012 by physicist and Nobel Prize winner Frank Wilczek of the Massachusetts Institute of Technology. These space-time crystals are theoretical quantum systems that oscillate periodically while in the standard state, the lowest energy state.
The idea of creating a quantum space-time crystal turned out to be so attractive that a group of physicists from the University of California at Berkeley even started preparing for the creation of an experimental setup in which calcium ions trapped in an annular ion trap played the role of a crystal. Under the influence of an extremely weak magnetic field, calcium ions should begin to rotate slowly, while being in the lowest energy state. Theoretically, the rotation of such a system can continue indefinitely, even after the thermal death of the Universe, because such a system does not absorb or emit energy.
But, like any exotic physical theory, the theory of space-time crystals, in addition to adherents, also has ardent opponents. One of the opponents of this theory is the famous physicist Patrick Bruno (Patrick Bruno), who works in the laboratory of the European Synchrotron Radiation Facility, located in Grenoble, France. Bruno has repeatedly pointed out some "holes" in the theory of space-time crystals, and not so long ago he did not leave stone unturned from this theory, creating his own "stop theory", which completely excludes the possibility of infinite rotation of a wide class of systems located in standard state, which can be called space-time crystals.
According to Bruno's theory, the concept of space-time crystals has two main shortcomings. First, the rotating solitron (single wave impulse) that Vilkzek describes in his model is not in a standard, but in a higher energy state. Secondly, a system that performs rotational motion, albeit being in a standard state, can radiate energy into the surrounding space in the form of electromagnetic waves, which in itself is in conflict with the law of conservation of energy.
As the main argument of his theory, Bruno demonstrates that setting in motion a ring system of quantum particles around the ring of a magnetic trap will in any case increase the energy of the entire system, moving it from a standard to a higher energy state. Bruno believes that this is evidenced by the description of rotating systems described in the works of Nobel Laureate Anthony Leggett, who studied the properties of rotating superfluids, liquids with an infinite flow coefficient.
Bruno thinks his first argument should not come as a surprise, since a theory developed in 1964 by another Nobel Laureate, Walter Kohn, states that insulating materials are completely insensitive to magnetic fluxes and to their change. Since quantum space-time crystals are modeled as Wigner crystals, and Wigner crystals are known to be insulators, the magnetic flux and magnetic field cannot make the space-time crystal system rotate.
"I believe that by developing my "stopping theory", I put an end to the theory of the possibility of the existence of rotating space-time crystals. I am sorry that a lot of my time and the time of other scientists was spent on this initially incorrect theory. I have no plans to continue work in this direction, but if someone comes up with alternative options that do not conflict with existing theories, I will be happy to return to this topic again," writes Bruno.
