On Thursday, February 11, a group of scientists from the international project LIGO SCIENTFIC COLLABORATION said that they were able to exist in 1916 Albert Einstein predicted. According to researchers, on September 14, 2015, they recorded a gravitational wave, which was caused by a collision of two black holes weighing 29 and 36 times more than the mass of the Sun, after which they merged into one big black hole. According to them, this happened presumably 1.3 billion years ago at a distance of 410 megaparsecs from our galaxy.
Detail O. gravitational wavesah and large-scale opening of LІGA.net told Bogdan Gnatyk, Ukrainian scientist, Astrophysicist, Doctor of Physical and Mathematical Sciences, Leading Researcher of the Astronomical Observatory of Kiev national University Taras Shevchenko, who headed the observatory from 2001 to 2004.
Theory simple language
Physics studies interaction between bodies. It has been established that there are four types of interaction between bodies: electromagnetic, strong and weak nuclear interaction and gravitational interaction that we all feel. Due to the gravitational interaction of the planet rotate around the Sun, the body have a weight and fall to the ground. With gravitational interaction, a person is constantly facing.
In 1916, 100 years ago, Albert Einstein built the theory of gravity, which improved the Newtonian theory of gravity, made it mathematically correct: she began to answer all the requirements of physics, began to take into account the fact that gravity spreads with very large, but the final speed. This is right one of the most grand achievements of Einstein, as he built the theory of gravity, which meets all the phenomena of physics, which we are observing today.
This theory also assumed the existence gravitational waves. The basis of this prediction was that gravitational waves exist as a result of gravitational interaction, which arises due to the merger of two massive bodies.
What is a gravitational wave
Complex tongue This is the excitation of the Space-Time Metric. "Let's say, the space has a certain elasticity and the waves can run on it. It looks like when we throw the pebbles into the water and the waves run out of it," the doctor of physico-mathematical sciences told Liga.net.
Scientists managed to experimentally prove that such a oscillation took place in the universe and the gravitational wave ran in all directions. "Astrophysical method for the first time was recorded a phenomenon of such a catastrophic evolution dual systemWhen two objects are merged into one, and this merger leads to a very intense release of gravitational energy, which is then distributed in space in the form of gravitational waves, "the scientist explained.
What does it look like (photo - EPA)
These gravitational waves are very weak and so that they lay space-time, it is necessary to interact very large and massive bodies to tensions gravitational field It was big in the place of generation. But, despite their weakness, the observer through a certain time (equal to the distance to the interaction divided by the signal flow rate) will register this gravitational wave.
Let us give an example: if the land fell into the sun, the gravitational interaction would have happened: the gravitational energy would be released, a gravitational spherical-symmetric wave would have been formed and the observer could register it. "It also happened similar, but unique, from the point of view of astrophysics, the phenomenon: two massive bodies were collided - two black holes," said Gnatyk.
Let's go back to the theory
A black hole is another prediction of the general theory of Einstein's relativity, which provides that the body that has a huge mass, but this mass is concentrated in a small volume, can significantly distort the space around itself, up to its closure. That is, it was assumed that when the critical concentration of the mass of this body is achieved - such that the body size will be less than the so-called gravitational radius, then around this body, the space will be closed and the topology of it will be such that no signal from it beyond the closed space can not.
"That is, a black hole, simple wordsThis is a massive object that is so heavy that the space-time closes around itself, "the scientist says.
And we, according to him, we can send any signals to this object, and it is not for us. That is, no signals can go beyond the black hole.
Black Hole lives according to ordinary physical laws, but as a result of strong gravity, none material bodyEven the photon is not able to go beyond this critical surface. Black holes are formed during the evolution of ordinary stars, when the collapse of the central kernel and part of the star substance, collapsy, turns into a black hole, and the other part of the star is thrown into the form of a supernova shell, turning into the so-called "flash" of a supernova.
How we saw a gravitational wave
Let us give an example. When we have two floors and the water is calm - then the distance between them is constant. When the wave comes, it shifts these floats and the distance between the floats will change. The wave passed - and the floats are returned to their previous positions, and the distance between them is restored.
The gravitational wave in space - time is also distributed: it compresses and stretches the bodies and objects that are found on its path. "When a certain object is found on the path of the wave - it is deformed along his axes, and after its passage - returns to the previous form. Under the action of gravitational waves, all the bodies are deformed, but these deformations are very insignificant," says Gnatyk.
When the wave was held, which scientists recorded, the relative size of the bodies in space changed by magnitude of about 1 multiplied by 10 per minus 21th degree. For example, if you take a meter ruler, it squeezed on such a value that was its size multiplied by 10 per minus 21th degree. This is a very meager value. And the problem was that scientists needed to learn this distance to measure. Conventional methods gave the accuracy of about 1 to 10 V 9 degrees of Milionnam, and here is needed much higher accuracy. To do this, created the so-called gravitational antennas (gravitational wave detectors).
LIGO Observatory (Photo - EPA)
Antenna, which recorded gravitational waves, is constructed in this way: there are two pipes, approximately 4 kilometers in length, located in the form of the letter "g", but with the same shoulders and at right angles. When a gravitational wave falls on the system, it deforms the wings of the antenna, but depending on its orientation, it deforms one more, and the second is less. And then the difference difference occurs, the interference pattern of the signal changes - the total positive or negative amplitude occurs.
"That is, the passage of a gravitational wave is similar to the wave on the water passing between two floats: if we measure the distance between them during and after passing the wave, then we would see that the distance would change, and then it became the same again," said Gnatyk.
Here the relative change in the distance of two wings of the interferometer is measured, of which each has about 4 kilometers in length. And only very accurate technologies and systems make it possible to measure such a microscopic shift of the wings caused by the gravitational wave.
On the border of the Universe: where did the wave come from
Scientists recorded a signal with the help of two detectors, which in the US are located in two states: Louisiana and Washington at a distance of about 3 thousand kilometers. Scientists managed to evaluate where this signal came from and from what distance. Evaluations show that the signal came from a distance that is 410 megapars. Megaparec is the distance that light passes over three million years.
To make it easier to imagine: the nearest active galaxy to us with supermassive black hole in the center - Centaur A, which is from our four megaparseca, at the same time, the nebula of Andromeda is 0.7 megaparsec. "That is, the distance from which the signal of the gravitational wave came so large that the signal went to Earth about 1.3 billion years. These are cosmological distances that reach about 10% of the horizon of our universe," the scientist told.
At this distance in some distant galaxy, the fusion of two black holes occurred. These holes, on the one hand, were relatively small in size, and on the other hand, big power The amplitudes of the signal indicates that they were very heavy. It was established that their masses were, respectively, 36 and 29 masses of the sun. The mass of the sun, as is known, is the value that is equal to 2 multiply by 10 at 30 a kilogram degrees. After the merger, these two bodies merged and now one black hole was formed in their place, which has a mass equal to 62 solutions of the sun. At the same time, about three masses of the Sun spilled out as the energy of the gravitational wave.
Who and when did the discovery
Detect a gravitational wave managed by scientists from the international project LIGO on September 14, 2015. Ligo. LASER INTERFEROMETRY GRAVITATION OBSERVATORY) - This is an international project in which a number of states that have implemented a certain financial and scientific contribution, in particular the United States, Italy, Japan, who are advanced in these studies.
Profures Rainer Weiss and Kip Thorn (Photo - EPA)
The following picture was recorded: the wings of the gravitational detector occurred, as a result of the real passage of the gravitational wave through our planet and through this installation. This was not reported then, because the signal had to be processed, "clean", to find his amplitude and check. it standard procedure: from the real discovery, before the opening announcement - passes several months to issue a reasonable statement. "No one wants to spoil her reputation. These are all secret data, before the publication of which no one knew about them, only rumors went," said Gnatyk.
History
Gravitational waves are investigated from the 70s of the last century. During this time a number of detectors were created and a number of fundamental studies were held. In the 1980s, the American scientist Joseph Weber built the first gravitational antenna in the form of an aluminum cylinder, which had the size of the order of several meters, equipped with piezo sensors, which were supposed to fix the passage of the gravitational wave.
The sensitivity of this device was a million times worse than the current detectors. And, of course, he could not really fix the wave, although Weber stated that he did this: the press wrote about it and there was a "gravitacion boom" - the gravitational antennas began to build in the world. Weber stimulated other scientists to make gravitational waves and continue experiments on this phenomenon, thanks to which it was possible to raise the sensitivity of the detectors.
However, the phenomenon of gravitational waves was registered in the last century, when scientists have discovered a double pulsar. It was an indirect registration of the fact that gravitational waves exist, proven due to astronomical observations. Pulsar was opened by Russell Khals and Joseph Taylor in 1974, during the observations on a radio telescope Observatory Arecibo. Scientists were awarded Nobel Prize In 1993, "for the opening of a new type of pulsarov, which gave new opportunities in the study of gravity."
Research in peace and Ukraine
On the territory of Italy is close to completion, a similar project called Virgo. Japan also intends to launch a similar detector in a year, India also prepares such an experiment. That is, in many points of the world there are similar detectors, but they have not yet come to the mode of sensitivity so that you can talk about fixing gravitational waves.
"Officially, Ukraine is not included in Ligo and also does not participate in Italian and Japanese projects. Among such fundamental areas, Ukraine is now participating in the LHC project (Buck is a large adronle collider) and in CERN" E (officially by the participant only after payment of the entrance fee) "," said Lіga.net Doctor of Physical and Mathematical Sciences Bogdan Gnatyk.
According to him, Ukraine since 2015 is a full member of the CTA International Collaboration (MT-MID of the Cherenkov Telescope), which builds a modern multi telescope Tvgamma range (with photon energies up to 1014 eV). "The main sources of such photons are just the neighborhood of supermassive black holes, the gravitational radiation for the first time recorded ligo detector. Therefore, the opening of new windows in astronomy - gravitational wave and multi Tvthere is still many discoveries in the future, "adds a scientist.
What's next and how do new knowledge help people? Scientists disagree in opinions. Some say that this is only another step in understanding the mechanisms of the universe. Others see the first steps towards new movement technologies through time and space. One way or another - this discovery once again proved how little we understand and how much still have to find out.
A group of scientists from 16 countries first received proof of the existence of gravitational waves in practice. In this, they were helped by two black holes, which were connected to one 1.3 billion years ago. In the process there was such an emission of energy that forced the land to shake, like jelly. Fontanka tried to understand the proof presented.
Source: Ligo.
"We recorded a gravitational wave," Executive Director of Laser-Interferometric Gravitational Wave Observatory Laser-Interferometric Gravitational Wave Observatory stated at a press conference in Washington. His words caused a squall of applause. Nevertheless, not so often the fundamental science pleases the discoveries of a universal scale.
The study really goes beyond the planet. The source of oscillations, which managed to detect scientists, is somewhere in the southern part of the starry sky. The wave came from the side of the Magellan clouds, which are galaxies satellites Milky Way. The possible location of the source with a different probability is noted on the map below.
About 1.3 billion years ago, scientists believe, there were fantastic events, when two black holes fell under the influence of each other and began to converge. Recall, "black holes" - a conditional name for space objects that attract everything is nearby. The strength of attraction is so great that even the light cannot break out of their limits. Because of this on the background bright stars And the objects illuminated by them are "black holes" look absolutely dark.
And here two such objects began to attract each other, moving along the snail. Thus, they created indignation in the gravitational field, and gravitational waves began to disperse from their movement. The process ended logically: connected to one space object. Visually, it is similar to the division of the cell, which is familiar to all of the biology textbook, launched in the opposite direction.
LIGO researchers celebrate critical moment For the millisecond to the final connection of two "black holes" in one, when the energy release occurred, 50 times greater than the energy of all stars in the universe.
Source: Ligo.
A peculiar "ninth tree" passed through the universe and rushed to the Earth. The wave struck in the planet and influenced its gravitational field. For clarity, scientists explained that the effect was similar to what would be, if you poke something jelly and it will start shaking. However, for the planet, such concussions are not hazardous, and nothing but super-sensitive devices are not fixed. The co-founder LIGO Raigner Weiss clearly demonstrated how specifically the wave passes through the gravitational field.
By the time the wave reached the land, experimental studies in search of gravitational waves were already a quarter of a century. It must be said that the theoretical possibility of the existence of gravitational waves is mentioned in several theories. For example, according to the general theory of the relativity of Einstein, the speed of propagation of the gravitational wave is equal to the speed of light in the linear approximation.
However, it was impossible to experimentally experimentally or confirm one of theories, due to the fact that it is very difficult to detect a gravitational wave. To understand the scale of such a phenomenon, it is necessary to know that in the solar system the most powerful sources of gravitational waves are, in fact, the sun and Jupiter. And the power of these waves is insignificant, compared with the kinetic energy of these bodies, 5 kilowatt.
However, on September 14, 2015, at once, two gravitational and wave observatory in the United States managed to fix oscillations, which were subsequently identified by scientists as gravitational waves. At first, the oscillations were recorded in the city of Hanford Washington State, and after 7 milliseconds in Livingston, Louisiana. The recheck of all data took about six months. After that, scientists were able to tell how they managed to catch a gravitational wave.
A laser interferometer was used to measure. The essence of its work lies in the separation of the laser beam on two, characterized by intensity. Each of them further reaches the mirror, where it is reflected and returns to the system, and already from there it is sent to a special photodetector. The principle of operation of the system is depicted in the video below.
Source: Ligo.
Mirrors are at a considerable distance from the laser and are isolated from foreign oscillations. When the gravitational wave passes through the ground, its form changes, which means that the distance of the mirrors from the radiation source. As a result, after the reflection of the laser beam from the mirror, the beam needs more or less distance to reach the photodetector. The microscopic difference in the release of the laser onto the photodetector is precisely the method of determining the gravitational wave.
For greater clarity, scientists have determined the color of the amplitude of the gravitational wave. The representative of Ligo from the University of Louisiana Gabriela Gonzalez also stated that the gravitational wave is in the range that the human ear can catch. "We can literally hear a gravitational wave, we can hear the universe. However, this wave is so short that we will only hear the sound similar to the "plunk!" - explained Gonzalez.
Fontanka readers also suggest to hear the gravitational wave, which appeared about 1.3 billion years ago as a result of the connection of two black holes in a distant-distant galaxy.
"Not so long ago, the strong interest of the scientific community has caused a series of long-term experiments on the direct observation of gravitational waves, - wrote a specialist in the field theoretical physics Mitio Kaku in the book "Einstein space" in 2004. - The LIGO project ("Laser interferometer to observe gravitational waves") may be the first, during which the gravitational waves will be able to "see", most likely, from the collision of two black holes in the far space. Ligo - the next physics dream, the first installation of sufficient power to measure gravitational waves. "
Prediction Kaku came true: on Thursday, a group of international scientists from the LIGO Observatory announced the opening of gravitational waves.
Gravitational waves are oscillations of space-time that "run away" from massive objects (for example, black holes) moving with acceleration. In other words, gravitational waves are a propagating space-time perturbation, the running deformation of the absolute void.
The black hole is an area in space-time, the gravitational attraction of which even objects moving at the speed of light can not leave it (and the light itself). The border separating the black hole from the rest of the world is called the horizon of events: everything that happens inside the event horizon is hidden from the eye of an external observer.
Erin Ryan Cake snapshot, laid out in Erin Ryan.
Catch the gravitational waves scientists began to half a century ago: It was then that American physicist Joseph Weber became interested in the general theory of Einstein's relativity (from), took a creative vacation and began to study gravitational waves. Weber invented the first adaptation, detecting gravitational waves, and soon stated that she recorded the "sound of gravitational waves". However, the scientific community denied his message.
However, it was thanks to Joseph Weber a lot of scientists turned into "wave hunters." Today Weber is considered the father of the scientific direction of gravitational wave astronomy.
"It is the beginning of a new era of gravitational astronomy"
The LIGO Observatory in which scientists recorded gravitational waves consists of three laser installations in the USA: two are in Washington and one state in Louisiana. This is how Mitio Laser Detectors describes the work: "The laser beam is split into two separate beams, which further go perpendicular to each other. Then, reflected from the mirror, they are again connected. If a gravitational wave passes through the interferometer (measuring instrument), the length of the paths of two laser rays Put perturbation and will reflect in their interference picture. To make sure the signal is registered laser installation, not accidents, detectors should be placed in different points Earth.
Only under the action of a giant gravitational wave, much greater than the size of our planet, all detectors will work at the same time. "
Now the ligo collaboration recorded gravitational radiation caused by a merge of the double system of black holes with masses 36 and 29 solar masses In the object weighing 62 mass of the sun. "This is the first direct (it is very important that it is a direct!) Measurement of the action of gravitational waves," Professor of the Physics Department of Moscow State University gave a comment, Professor of the Physics Department of Moscow State University. - That is, a signal from the astrophysical catastrophe of the merger of two black holes is taken. And this signal is identified - it is also very important! It is clear that it is from two black holes. And it is the beginning new era gravitational Astronomywhich will allow to obtain information about the universe not only through optical, x-ray, electromagnetic and neutrine sources - but also through gravitational waves.
It can be said that percentage of 90 black holes ceased to be hypothetical objects. Some share of doubt remains, but still a signal that is caught, it hurts well well on what is predicted with countless simulations of the merger of two black holes in accordance with the general theory of relativity.
This is a strong argument that black holes exist. There is no other explanation to such a signal yet. Therefore, it is assumed that black holes exist. "
"Einstein would be very happy"
Gravitational waves in the framework of their general theory of relativity predicted Albert Einstein (which, by the way, skeptically referred to the existence of black holes). In addition to three spatial dimensions, time is added, and the world becomes four-dimensional. According to the theory that turned upside down on the head of all physics, gravity is a consequence of the curvature of space-time under the influence of mass.
Einstein proved that any matter moving with acceleration creates a disturbance of space-time - a gravitational wave. This indignation is the greater, the higher the acceleration and mass of the object.
Due to the weakness of gravitational forces compared to other fundamental interactions, these waves should have a very small amount, with difficulty registration.
Explaining from the humanities, physics often ask them to present a tensioned rubber sheet, which is lowered by massive balls. Balls pose rubber, and a sheet stretched (which personifies space-time) deformed. According to OTO, the entire Universe is a rubber on which each planet, every star and each galaxy leave dents. Our land revolves around the Sun as if a small ball, fastened to ride around the cone of the funnel formed as a result of the "plot" of space-time with a heavy ball.
Handout / Reuters
Heavy ball - this is the sun
It is likely that the opening of gravitational waves, which is the main confirmation of the Einstein theory, claims to the Nobel Prize in Physics. "Einstein would be very happy," said Gabriella Gonamez, a representative of LIGO collaboration.
According to scientists, while it is too early to talk about the practical applicability of the opening. "Although Henry Hertz (a German physicist, who has proven the existence of electromagnetic waves. -" Gazeta.Ru ") might think that mobile phone? Not! We can not imagine anything now, "said Valery Mitrofanov, Professor of Physical Faculty of Moscow State University. M.V. Lomonosov. - I focus on the film "InterSellar". He is criticized, yes, but even a wild man could imagine the carpet. And the carpet airplane was realized by the plane, and that's it. And here you already need to imagine something very complicated. In InterSellar, one of the moments is associated with the fact that a person can travel from one world to another. If you imagine, then do you believe that a person can travel from one world to another that there may be a lot of universes - whatever? I can't answer "no." Because the physicist cannot answer such a question "No"! Only if it contradicts some kind of conservation laws! There are options that do not contradict well-known physical laws. So traveling around the worlds can be! "
What means for us the detection of gravitational waves.
I think everything is already aware that a couple of days ago, scientists first announced the detection of gravitational waves. About it was a lot of news, on TV, on news sites and generally everywhere. However, no one made it difficult to explain available languageWhat gives us this discovery in a practical plan.
In fact, everything is simple, it is enough to carry out an analogy with a submarine:
A source:
The detection of submarines is the first and main task in dealing with them. Like any subject, the boat affects its presence on environment. In other words, the boat has its own physical fields. The more famous physical fields of the submarine include hydroacoustic, magnetic, hydrodynamic, electric, low-frequency electromagnetic, as well as thermal, optical. The discharge of the physical fields of the boat against the background of the ocean fields (sea) is based on the main methods of detection.
Ways to detect submarines are separated by type of physical fields: acoustic, magnetometric, radar, gas, thermal I.T.D.
With the same garbage space. We look at the stars through telescopes, make photos of Mars, we catch radiation and in general trying to know the heavens by all available methods. And now, after these waves are recorded, another study is added - gravitational. We will be able to inspect the space based on these fluctuations.
That is, as a submarine passed in the marine space, and left the "footprint", according to which it can calculate, exactly the same heavenly bodiesNow they can be studied at a different angle for a more complete picture. In the future, we will be able to see how the gravitational waves are enveloped by different shines, galaxies, planets, learn even better to calculate the space trajectories of objects (and may even know in advance and predict the approximation of meteorites) We will see the behavior of the waves in special conditions, Well, anything.
What will it give?
It's not clear yet. But over time, the equipment will become more accurate and sensitive, and rich material will be raised about gravitational waves. Based on these materials, the inquisitive minds will begin to find various kinds of anomalies, riddles and patterns. These patterns and anomalies, in turn, will serve either by refutation or confirmation of old theories. Additional will be created mathematical formulas, interesting hypotheses (British scientists found out that the pigeons find the way home focusing on gravitational waves!) And much like. And the yellow press, it will definitely launch any myth, like the "gravitational tsunami", which will once be granted, will cover our solar system and Kidyk will come to everything. And Vantu is shy away. In short, it will be fun:]
And what's the result?
As a result, we will get a more advanced area of \u200b\u200bscience that can give a more accurate and wide view of our world. And if some amazing effect goes and scientists will fall ... (like, if two gravitational waves in the full moon "are crashed" to each other at a certain angle at the right speed, the local focus of anti-gravity happens, O-Pa!) ... We can hope for serious scientific progress.
On February 11, 2016, an international group of scientists, including from Russia, at a press conference in Washington announced the opening, which sooner or later changes the development of civilization. It was possible in practice to prove gravitational waves or waves of space-time. Their existence was predicted 100 years ago Albert Einstein in his.
No one doubts that this discovery will be awarded the Nobel Prize. Scientists do not rush to talk about him practical application. But it reminds that even recently, humanity also did not know what to do with electromagnetic waves, which eventually led to a real scientific and technological revolution.
What is gravitational waves in simple language
Gravity and global gravity is the same thing. Gravitational waves are one of the solutions of OTS. They should spread with the speed of light. It radiates his any body moving with variable acceleration.
For example, it rotates in its orbit with variable acceleration directed towards the star. And this acceleration is constantly changing. solar system Rades the energy of the order of several kilowatts in gravitational waves. This is an insignificant value, comparable with 3 old color TVs.
Another thing is two spisar rotating around each other ( neutron stars). They rotate at very close orbits. Such a "couple" was discovered by astrophysics and was observed for a long time. Objects were ready to fall at each other, which indirectly testified that the pulsars emit the waves of space-time, that is, the energy in their field.
Gravity is the force of gravity. We are pulling to the ground. And the essence of the gravitational wave is a change in this field, extremely weak when it comes to us. For example, take the water level in the reservoir. The tension of the gravitational field is to accelerate the free fall at a specific point. On our reservoir runs the wave, and suddenly the acceleration of free fall is changing, quite a little bit.
Such experiments began in the 60s of the last century. At that time, they came up with this: huge aluminum cylinder were suspended, cooled to avoid domestic heat oscillations. And waited for us to suddenly make a wave from a collision, for example, two massive black holes. Researchers were full of enthusiasm and said that the entire globe could experience the impact of a gravitational wave flew from outer space. The planet will begin to fluctuate, and it will be possible to study these seismic waves (compression, shear and superficial).
An important article on the device is a simple language, and as Americans and Ligo stole the idea of \u200b\u200bSoviet scientists and built introfer meters that allowed to make a discovery. No one speaks about it, everyone is silent!
By the way, gravitational radiation is more interesting from the position of relict radiation, which is trying to change the spectrum of electromagnetic radiation. Relicate I. electromagnetic radiation 700 thousand years have appeared after a large explosion, then in the process of expanding the universe filled with hot gas with running shock waves, which later turned into galaxies. At the same time, naturally, a giant, a breathtaking amount of space-time waves affecting the wavelength of relict radiation, which was still optical at that time were still optical at that time. Domestic astrophysicist Sainza writes and regularly publishes articles on this topic.
Invalid interpretation of the opening of gravitational waves
"Hanging the mirror, a gravitational wave acts on it, and it begins to fluctuate. And even the most minor fluctuations in the amplitude less than the size of the atomic nucleus are noted by appliances, "such incorrect interpretation, for example, is used in the Wikipedia article. Do not be lazy, find the article of Soviet scientists in 1962.
First, the mirror must be massive to feel "ripples". Secondly, it needs to be cooled almost to absolute zero (Kelvin) to avoid their own thermal oscillations. Most likely not that in the 21st century, but in general will never be able to detect elementary particle - carrier of gravitational waves:
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