What is the law of universal gravitation definition. Gravity and gravity
It is not by chance that Newton's law is called universal. Its scope is not limited to the Earth and even the Solar System. He describes the interaction of any bodies in the Universe: stars, planets, satellites, comets, meteorites.
Why do apples fall down?
At the same time that the young scientist Isaac Newton received his bachelor's degree, an epidemic of plague broke out in England. The University of Cambridge was closed, and Newton went to his mother's estate. The two years that he spent there completely changed the science of that time, because Newton made several fundamental discoveries, including the deduction of the law of universal gravitation.
As he told in old age, the idea of the existence of the law of universal gravitation came to him when he watched ripe apples fall from the trees. At that moment, the moon was visible in the sky. And now, looking at the Moon, which, as he knew, revolves around the Earth, and at the apples that are falling down, Newton suddenly realized that in both cases the same force is acting. This force makes earthly objects fall down, and it also keeps the Earth satellite in orbit, preventing it from rushing into space.
They say that the story of the apple falling on Newton's head is nothing more than a myth. But it is reliably known that the scientist loved to indulge in reflections in his mother's apple orchard.
It was the greatest discovery that explained with mathematical precision the movement of celestial objects and many phenomena that took place on Earth. The force of gravity (attraction) is one of the most universal in nature. It acts between any objects with mass. And since there is no matter without mass, there are no exceptions for this force. If we could see attraction in the form of threads, then at any point in space there would be an infinite number of such threads connecting everything with everything. It is impossible to "fence off" the force of gravity, there are no protective screens that would be an obstacle to this omnipresent force.
"Nature is simple and not luxurious with unnecessary reasons." Isaac Newton
Endless fall
Newton was not the first to notice bodies falling to Earth. Galileo also studied the acceleration of gravity. But he believed that the force of gravity acts only on the Earth, the maximum - extends to the Moon. Kepler, who discovered the laws of planetary motion, was convinced that these laws are valid only in space. And only the genius of Newton made it possible to unite "earthly" and "heavenly". Newton was the first to prove that the same forces and the same laws operate both on Earth and in space, and the most important of them is the law of universal gravitation.
In order to better understand the unity of this law, you can conduct a thought experiment. Imagine that we are standing on the edge of a high cliff, next to an old cannon, and heavy cast-iron cannonballs lie at our feet. If you just push the core off the cliff, then it will fall vertically downward. If you shoot a cannonball, it will also fall, but first it will fly forward and describe an arc in the air. Here, in addition to the gravitational force, the nucleus is acted upon by another force that gives it the initial acceleration.
Now let's try to imagine that our super-powerful cannon can shoot a core with such force that it flew around the Earth and again returned to its starting point. What happens in this case? The core will not fall, but will continue to move around our planet in a circular orbit. It turns out that we have created an artificial satellite.
This book by Newton is one of the most important in the history of mankind. Its title, translated from Latin, means "Mathematical Principles of Natural Philosophy."
In fact, the movement of the Moon around the Earth, the Earth around the Sun or an artificial satellite around the planet is a constant "fall" caused by the force of gravity and explained by the law of universal gravitation. Due to the fact that the speed of movement is very high, the smaller body does not fall for a larger one, tending to move in a straight line. But they also cannot fly away, since they are held by the omnipresent force of gravity - the same one that makes apples fall down.
"He did not allow himself any rest and respite ... he considered lost every hour not devoted to his studies ... I think he was saddened a lot by the need to spend time on food and sleep," his assistant recalled about Newton
I decided to dwell on lighting as much as I could. scientific heritage Academician Nikolai Viktorovich Levashov, because I see that his works today are not yet in demand, which they should have enjoyed in a society of truly free and reasonable people. People still do not understand the value and importance of his books and articles, because they are not aware of the degree of deception in which we have been living for the last couple of centuries; do not understand that information about nature, which we consider habitual and therefore true, is false by 100%; and they are deliberately imposed on us in order to hide the truth and prevent us from developing in the right direction ...
The law of universal gravitation
Why do we need to deal with this gravity? Don't we know something about her yet. What are you! We already know a lot about gravity! For example, Wikipedia kindly informs us that « Gravity (attraction, worldwide, gravitation) (from Lat. gravitas - "heaviness") - a universal fundamental interaction between all material bodies. In the approximation of low speeds and weak gravitational interaction, it is described by Newton's theory of gravitation, in the general case, it is described by Einstein's general theory of relativity ... " Those. Simply put, this Internet chatter says that gravity is the interaction between all material bodies, and even more simply - mutual attraction material bodies to each other.
We owe this opinion to Comrade Isaac Newton, credited with discovering in 1687 "The law of universal gravitation", according to which all bodies are allegedly attracted to each other in proportion to their masses and inversely proportional to the square of the distance between them. The good news is that Comrade Isaac Newton is described in Pedia as a highly educated scientist, unlike Comrade. credited with discovering electricity…
It is interesting to look at the dimension of the "force of attraction" or "force of gravity", which follows from com. Isaac Newton, which has the following form: F =m 1 *m 2 /r 2
The numerator contains the product of the masses of the two bodies. This gives the dimension "kilograms squared" - kg 2... The denominator is "distance" squared, i.e. meters squared - m 2... But strength is not measured in strange kg 2 / m 2, and in no less strange kg * m / s 2! It turns out a mismatch. To remove it, "scientists" have come up with a coefficient, the so-called. "Gravitational constant" G equal to approximately 6.67545 × 10 −11 m³ / (kg · s²)... If we multiply everything now, we get the correct dimension of the "Gravity" in kg * m / s 2, and this gibberish is called in physics "Newton", i.e. strength in today's physics is measured in "".
And I wonder what physical meaning has a coefficient G , for some reason decreasing the result in 600 billion times? None! "Scientists" called it "proportionality factor." And they introduced him to fit dimension and result under the most desirable! This is our science today ... It should be noted that, in order to confuse scientists and hide contradictions, the measurement systems in physics have changed several times - the so-called. "Systems of units"... Here are the names of some of them, replacing each other, as the need to create new disguises arises: MTS, MKGSS, SGS, SI ...
It would be interesting to ask Comrade Isaac: a as he guessed that there is a natural process of attracting bodies to each other? As he guessed that the "force of attraction" is proportional to the product of the masses of two bodies, and not to their sum or difference? How he so successfully comprehended that this Force is inversely proportional to the square of the distance between bodies, and not to a cube, doubling or fractional power? Where at Comrade there were such inexplicable guesses 350 years ago? After all, he did not conduct any experiments in this area! And, if you believe the traditional version of history, in those days even the rulers were still not quite even, but here such an inexplicable, simply fantastic sagacity! Where?
Yes out of nowhere! Comrade Isaac had no idea of anything like that and did not investigate anything of the kind and did not open... Why? Because in reality the physical process " attraction tel " to each other does not exist, and, accordingly, there is no Law that would describe this process (this will be convincingly proved below)! In reality, Comrade Newton in our indistinct, just attributed the discovery of the law of "Universal gravitation", at the same time awarding him the title of "one of the creators of classical physics"; in the same way as comrade. Bene Franklin, which had 2 class education. In "Medieval Europe" this did not happen: there was a lot of tension not only with the sciences, but also with life ...
But, fortunately for us, at the end of the last century, the Russian scientist Nikolai Levashov wrote several books in which he gave the "alphabet and grammar" undistorted knowledge; returned to earthlings the previously destroyed scientific paradigm, with the help of which easily explained practically all "insoluble" riddles of earthly nature; explained the basics of the structure of the Universe; showed under what conditions on all planets on which necessary and sufficient conditions appear, Life- living matter. Explained what kind of matter can be considered alive, and what physical meaning natural process called " life". He further explained when and under what conditions "living matter" acquires Intelligence, i.e. realizes its existence - it becomes reasonable. Nikolay Viktorovich Levashov conveyed to people in his books and films a lot undistorted knowledge... Including, he explained and what is "Gravity" where it comes from, how it works, what is its physical meaning in reality. Most of all this is written in books and. And now let's deal with the "Law of Universal Gravitation" ...
"The law of universal gravitation" is an invention!
Why am I so boldly and confidently criticizing physics? Isaac Newton and the "great" "Law of universal gravitation" itself? Because this "Law" is an invention! Deception! Fiction! A worldwide scam to lead earthly science to a dead end! The same scam with the same goals as the notorious "Theory of Relativity" comrade. Einstein.
Proof? Excuse me, here they are: very precise, strict and convincing. They were superbly described by the author O.Kh. Rustic in his wonderful article. In view of the fact that the article is quite voluminous, I will give here a very short version of some evidence of the falsity of the "Law of Universal Gravity", and citizens who are interested in the details will finish reading the rest themselves.
1. In our solar the system gravity is possessed only by the planets and the Moon - a satellite of the Earth. The satellites of the other planets, and there are more than six dozen of them, do not have gravity! This information is completely open, but not advertised by the "scientist" people, because it is inexplicable from the point of view of their "science". Those. b O Most of the objects in our solar system do not have gravity - they do not attract each other! And this completely refutes the "Law of universal gravitation".
2. Henry Cavendish's experience the attraction of massive blanks to each other is considered irrefutable proof of the presence of attraction between bodies. However, despite its simplicity, this experience is not overtly reproduced anywhere. Apparently, because it does not give the effect that some people once announced. Those. today, with the possibility of rigorous verification, experience shows no attraction between bodies!
3. Artificial satellite launch into orbit around the asteroid. Mid February 2000 of the year the Americans drove a space probe NEAR close enough to the asteroid Eros, equalized the speeds and began to wait for the capture of the probe by the gravity of Eros, i.e. when the satellite is gently pulled by the gravity of the asteroid.
But the first date for some reason did not work out. The second and subsequent attempts to surrender to Eros had exactly the same effect: Eros did not want to attract the American probe. NEAR, and without the engine running, the probe did not stay near Eros . This cosmic rendezvous ended in nothing. Those. no attraction between probe with mass 805 kg and an asteroid weighing more than 6 trillion tons could not be found.
Here one cannot fail to note the inexplicable stubbornness of the Americans from NASA, because the Russian scientist Nikolay Levashov living at that time in the United States, which he then considered a completely normal country, he wrote, translated into English and published in 1994 year his famous book, in which "on fingers" he explained everything that NASA specialists needed to know in order for their probe NEAR did not dangle a useless piece of iron in Space, but brought at least some benefit to society. But, apparently, exorbitant conceit played a trick with the local "scientists".
4. Next try they undertook to repeat the erotic experiment with an asteroid Japanese... They selected an asteroid called Itokawa, and sent on May 9 2003 years to him a probe called ("Falcon"). In September 2005 year, the probe approached the asteroid at a distance of 20 km.
Taking into account the experience of the "dumb Americans", the smart Japanese equipped their probe with several engines and an autonomous short-range navigation system with laser rangefinders, so that it could approach the asteroid and move around it automatically, without the participation of ground operators. “The first number of this program turned out to be a comedy stunt with the landing of a small research robot on the surface of an asteroid. The probe descended to the calculated height and carefully dropped the robot, which was supposed to slowly and smoothly fall to the surface. But ... he did not fall. Slowly and smoothly it suffered somewhere far from the asteroid... There he disappeared without a trace ... The next program number was, again, a comedy trick with a short-term landing of a probe on the surface "to take a soil sample." It turned out to be comedic because a reflective marker ball was dropped on the surface of the asteroid to ensure the best performance of the laser rangefinders. There were no engines on this ball either, and ... in short, there was no ball in its proper place ... So whether the Japanese "Falcon" sat on Itokawa, and what he did on it, if he sat down, is unknown to science ... "Conclusion: the Japanese miracle of Hayabusa is not was able to find no attraction between probe mass 510 kg and an asteroid mass 35 000 tons.
Separately, I would like to note that an exhaustive explanation of the nature of gravity by the Russian scientist Nikolay Levashov gave in his book, which he first published in 2002 year - almost a year and a half before the start of the Japanese "Falcon". Despite this, the Japanese "scientists" followed exactly in the footsteps of their American colleagues and carefully repeated all their mistakes, including the landing. Here is such an interesting continuity of "scientific thinking" ...
5. Where do the tides come from? A very interesting phenomenon described in the literature, to put it mildly, is not entirely correct. “... There are textbooks on physics, where it is written, what should be - in accordance with the "law of universal gravitation." And there are also tutorials on oceanography where it is written what they are, the tides, in fact.
If the law of universal gravitation is valid here, and ocean water is attracted, including to the Sun and the Moon, then the "physical" and "oceanographic" pictures of tides should coincide. Are they the same or not? It turns out that to say that they do not coincide is to say nothing. Because the "physical" and "oceanographic" pictures do not have each other at all. nothing in common... The actual picture of tidal phenomena is so different from the theoretical one - both qualitatively and quantitatively - that on the basis of such a theory one can predict the tides impossible... Nobody is trying to do it. Not crazy, after all. They do it this way: for each port or other point of interest, the dynamics of the ocean level is modeled by the sum of fluctuations with amplitudes and phases that are found cleanly empirically... And then extrapolate this amount of forward fluctuations - here you get the pre-calculations. The captains of the ships are happy - well, okay! .. "This all means that our earth tides too do not obey"The law of universal gravitation."
What is gravity in reality
For the first time in modern history, the real nature of gravity was clearly described by Academician Nikolai Levashov in his fundamental scientific work. For the reader to better understand what has been written about gravity, I will give a small preliminary explanation.
The space around us is not empty. It is all completely filled with many different matters, which academician N.V. Levashov named "Primary matter"... Previously, scientists called all this riot of matter "Ether" and even received convincing evidence of its existence (the well-known experiments of Dayton Miller, described in Nikolai Levashov's article "Theory of the Universe and Objective Reality"). Modern "scientists" have gone much further and now they "ether" are called "Dark matter"... Colossal progress! Some matter in the "ether" interact with each other to one degree or another, some do not. And some primary matter begins to interact with each other, falling into changed external conditions in certain curvatures of space (inhomogeneities).
Space curvatures appear as a result of various explosions, including "supernova explosions". « During a supernova explosion, fluctuations in the dimensionality of space arise, similar to the waves that appear on the surface of the water after a stone is thrown. The masses of matter ejected during the explosion fill these inhomogeneities in the dimension of space around the star. From these masses of matter, planets (and) begin to form ... "
Those. planets are not formed from space debris, as for some reason modern "scientists" assert, but are synthesized from the matter of stars and other primary matter, which begin to interact with each other in suitable inhomogeneities of space and form the so-called. "Hybrid matter"... It is from these "hybrid matters" that the planets and everything else in our space are formed. our planet, like the rest of the planets, is not just a "piece of stone", but a very complex system consisting of several spheres nested one into another (see). The densest sphere is called the "physically dense level" - it is visible to us, the so-called. physical world. The second in terms of density, a sphere of a slightly larger size is the so-called. The "etheric material level" of the planet. The third sphere - "astral material level". Fourth the sphere is the "first mental level" of the planet. The fifth the sphere is the "second mental level" of the planet. AND sixth the sphere is the "third mental level" of the planet.
Our planet should only be seen as the combination of these six spheres- six material levels of the planet, nested one into the other. Only in this case it is possible to get a full understanding of the structure and properties of the planet and of the processes occurring in nature. The fact that we are not yet able to observe the processes taking place outside the physically dense sphere of our planet indicates not that "there is nothing there," but only that at present our senses are not adapted by nature for these purposes. And one more thing: our Universe, our planet Earth and everything else in our Universe is formed from seven various types of primary matter merged into six hybrid matters. And this is neither divine nor unique. This is simply the qualitative structure of our Universe, due to the properties of the inhomogeneity in which it was formed.
Let's continue: the planets are formed when the corresponding primary matter merges in the regions of space inhomogeneities that have properties and qualities suitable for this. But in these, as in all the others, a huge number of prime matter(free forms of matter) of various types that do not interact or very weakly interact with hybrid matters. Getting into the area of heterogeneity, many of these primary matter are exposed to this heterogeneity and rush to its center, in accordance with the gradient (drop) of space. And, if a planet has already formed in the center of this heterogeneity, then primary matter, moving to the center of the heterogeneity (and the center of the planet), create directional flow, which creates the so-called. gravitational field... And, accordingly, under gravity you and I need to understand the impact of a directed flow of primary matter on everything that is on its way. That is, to put it simply, gravity is pinching material objects to the surface of the planet by the flow of primary matter.
Is not it, reality is very different from the fictitious law of "mutual attraction", which supposedly exists everywhere for no one understandable reason. Reality is much more interesting, much more complex and much simpler at the same time. Therefore, the physics of real natural processes is much easier to understand than fictional ones. And the use of real knowledge leads to real discoveries and the effective use of these discoveries, and not to sucked from the thumb.
Antigravity
As an example of today's scientific profanities we can briefly analyze the explanation by "scientists" of the fact that "rays of light are bent near large masses", and therefore we can see that it is closed to us by stars and planets.
Indeed, we can observe objects in Space that are hidden from us by other objects, but this phenomenon has nothing to do with the masses of objects, because the “universal” phenomenon does not exist, i.e. no stars, no planets NOT attract any rays to themselves and do not bend their trajectory! Why, then, are they "bent"? There is a very simple and convincing answer to this question: rays are not bent! They just do not spread in a straight line, as we used to understand, but in accordance with shape of space... If we consider a ray passing near a large cosmic body, then we must bear in mind that the ray bends around this body, because it is forced to follow the curvature of space, as if along a road of the corresponding shape. And there is simply no other way for the ray. The ray cannot but bend around this body, because the space in this area has such a curved shape ... Small to what has been said.
Now going back to antigravity, it becomes clear why Humanity does not manage to catch this nasty "anti-gravity" or achieve at least something from what the clever functionaries of the dream factory show us on TV. We are deliberately forced for more than a hundred years, internal combustion engines or jet engines have been used almost everywhere, although they are very far from being perfect both in terms of the principle of operation, in design, and in efficiency. We are deliberately forced mine using various generators of cyclopean sizes, and then transmit this energy through wires, where b O most of it dissipates in space! We are deliberately forced to live the life of unreasonable beings, therefore we have no reason to be surprised that we have nothing sensible, neither in science, nor in technology, nor in economics, nor in medicine, nor in organizing a decent life for society.
Now I will give you several examples of the creation and use of antigravity (aka levitation) in our life. But these ways to achieve antigravity are most likely discovered by accident. And in order to consciously create a really useful device that implements antigravity, you need to know the real nature of the phenomenon of gravity, to examine it, analyze and understand its whole essence! Only then can you create something sensible, effective and really useful to society.
The most common anti-gravity device we have is balloon and its many variations. If it is filled with warm air or a gas lighter than the atmospheric gas mixture, the ball will tend to fly up and not go down. This effect has been known to people for a very long time, but still does not have an exhaustive explanation- one that would no longer give rise to new questions.
A short search on YouTube led to the discovery of a large number of videos showing very real examples of antigravity. I will list some of them here so that you can make sure that antigravity ( levitation) does exist, but ... has not yet been explained by any of the "scientists", apparently, pride does not allow ...
The law of universal gravitation
Gravity (universal gravity, gravity)(from Lat. gravitas - "heaviness") - long-range fundamental interaction in nature, to which all material bodies are subject. According to modern data, it is a universal interaction in the sense that, unlike any other forces, all bodies without exception, regardless of their mass, are given the same acceleration. Mainly gravity plays a decisive role on a cosmic scale. Term gravity is also used as the name of the branch of physics that studies gravitational interaction. The most successful modern physical theory in classical physics describing gravity is general relativity; the quantum theory of gravitational interaction has not yet been built.
Gravitational interaction
Gravitational interaction is one of four fundamental interactions in our world. Within the framework of classical mechanics, the gravitational interaction is described the law of gravity Newton, who states that the force of gravitational attraction between two material points of mass m 1 and m 2 separated by distance R, proportional to both masses and inversely proportional to the square of the distance - that is
.Here G- gravitational constant equal to approximately 
m³ / (kg s²). The minus sign means that the force acting on the body is always equal in direction to the radius vector directed to the body, that is, the gravitational interaction always leads to the attraction of any bodies.
The law of universal gravitation is one of the applications of the inverse square law, which also occurs in the study of radiation (see, for example, Light pressure), and is a direct consequence of the quadratic increase in the area of a sphere with increasing radius, which leads to a quadratic decrease in the contribution of any unit area to the area of the entire sphere.
The simplest problem of celestial mechanics is the gravitational interaction of two bodies in empty space. This task is solved analytically to the end; the result of its solution is often formulated in the form of Kepler's three laws.
With an increase in the number of interacting bodies, the task becomes much more complicated. So, the already famous three-body problem (that is, the motion of three bodies with non-zero masses) cannot be solved analytically in a general form. With a numerical solution, the instability of the solutions with respect to the initial conditions sets in rather quickly. Applied to the solar system, this instability makes it impossible to predict the motion of the planets on scales exceeding a hundred million years.
In some special cases, it is possible to find an approximate solution. The most important is the case when the mass of one body is significantly greater than the mass of other bodies (examples: the solar system and the dynamics of Saturn's rings). In this case, as a first approximation, we can assume that light bodies do not interact with each other and move along Keplerian trajectories around the massive body. The interactions between them can be taken into account within the framework of perturbation theory and averaged over time. In this case, non-trivial phenomena such as resonances, attractors, chaos, etc. can arise. An illustrative example of such phenomena is the nontrivial structure of Saturn's rings.
Despite attempts to describe the behavior of a system of a large number of attracting bodies of approximately the same mass, this has not been possible due to the phenomenon of dynamic chaos.
Strong gravitational fields
In strong gravitational fields, when moving with relativistic speeds, the effects of the general theory of relativity begin to manifest themselves:
- deviation of the law of gravitation from Newtonian;
- potential lag associated with the finite speed of propagation of gravitational disturbances; the appearance of gravitational waves;
- nonlinearity effects: gravitational waves tend to interact with each other, so the principle of superposition of waves in strong fields is no longer fulfilled;
- changing the geometry of space-time;
- the emergence of black holes;
Gravitational radiation
One of the important predictions of general relativity is gravitational radiation, the presence of which has not yet been confirmed by direct observations. However, there is indirect observational evidence in favor of its existence, namely: the energy losses in the binary system with the PSR B1913 + 16 pulsar - the Huls-Taylor pulsar - are in good agreement with the model in which this energy is carried away by gravitational radiation.
Gravitational radiation can only be generated by systems with variable quadrupole or higher multipole moments, this fact suggests that the gravitational radiation of most natural sources is directional, which significantly complicates its detection. Gravitational power l-the field source is proportional to (v / c) 2l + 2 if the multipole is of electrical type, and (v / c) 2l + 4 - if the multipole is magnetic type, where v is the characteristic speed of movement of sources in the emitting system, and c is the speed of light. Thus, the dominant moment will be the quadrupole moment of the electric type, and the power of the corresponding radiation is equal to:
where Q ij is the tensor of the quadrupole moment of the mass distribution of the emitting system. Constant 
(1 / W) allows you to estimate the order of magnitude of the radiation power.
From 1969 (Weber's experiments) to the present day (February 2007), attempts have been made to directly detect gravitational radiation. In the USA, Europe and Japan at the moment there are several operating ground-based detectors (GEO 600), as well as the project of the space gravitational detector of the Republic of Tatarstan.
Subtle effects of gravity
In addition to the classical effects of gravitational attraction and time dilation, general relativity predicts the existence of other manifestations of gravity, which in terrestrial conditions are very weak and their detection and experimental verification are therefore very difficult. Until recently, overcoming these difficulties seemed beyond the capabilities of experimenters.
Among them, in particular, we can name the dragging of inertial frames of reference (or the Lense-Thirring effect) and the gravitomagnetic field. In 2005, NASA's robotic Gravity Probe B conducted an unprecedentedly accurate experiment to measure these effects near Earth, but the full results have yet to be published.
Quantum theory of gravity
Despite more than half a century of attempts, gravity is the only fundamental interaction for which a consistent renormalizable quantum theory has not yet been built. However, at low energies, in the spirit of quantum field theory, the gravitational interaction can be represented as an exchange of gravitons - gauge bosons with spin 2.
Standard theories of gravity
Due to the fact that the quantum effects of gravity are extremely small even under the most extreme experimental and observational conditions, there are still no reliable observations of them. Theoretical estimates show that in the overwhelming majority of cases one can restrict oneself to the classical description of the gravitational interaction.
There is a modern canonical classical theory of gravity - the general theory of relativity, and many hypotheses that refine it and theories of varying degrees of elaboration, competing with each other (see the article Alternative theories of gravity). All these theories give very similar predictions within the framework of the approximation in which experimental tests are currently being carried out. Several of the main, most well-developed or known theories of gravity are described below.
- Gravity is not a geometric field, but a real physical force field described by a tensor.
- Gravitational phenomena should be considered within the framework of the flat Minkowski space, in which the laws of conservation of energy-momentum and angular momentum are unambiguously fulfilled. Then the motion of bodies in Minkowski space is equivalent to the motion of these bodies in effective Riemannian space.
- In tensor equations to determine the metric, one should take into account the graviton mass, and also use the gauge conditions associated with the metric of the Minkowski space. This does not allow annihilating the gravitational field even locally by choosing some suitable frame of reference.
As in general relativity, in RTG, matter is understood as all forms of matter (including the electromagnetic field), with the exception of the gravitational field itself. The consequences of the RTG theory are as follows: black holes as physical objects predicted in general relativity do not exist; The universe is flat, homogeneous, isotropic, stationary and Euclidean.
On the other hand, there are no less convincing arguments from the opponents of RTG, which boil down to the following provisions:
A similar situation takes place in the RTG, where the second tensor equation is introduced to take into account the connection between the non-Euclidean space and the Minkowski space. Due to the presence of a dimensionless adjustable parameter in the Jordan - Brans - Dicke theory, it becomes possible to choose it so that the results of the theory coincide with the results of gravitational experiments.
| Theories of gravity | ||||||||
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Sources and Notes
Literature
- V.P. Vizgin Relativistic theory of gravitation (origins and formation, 1900-1915). M .: Nauka, 1981 .-- 352c.
- V.P. Vizgin Unified theories in the 1st third of the twentieth century. M .: Nauka, 1985 .-- 304c.
- Ivanenko D. D., Sardanashvili G. A. Gravity, 3rd ed. M.: URSS, 2008 .-- 200p.
see also
- Gravimeter
Links
- The law of universal gravitation or "Why does the moon not fall to the earth?" - Just about the difficult
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We all walk on the Earth because it attracts us. If the Earth did not attract all the bodies on its surface, then we, pushing off from it, would fly into space. But this does not happen, and everyone knows about the existence of gravity.
Are we pulling the Earth? The moon attracts!
Do we attract the Earth to ourselves? Funny question, isn't it? But let's figure it out. Do you know what the ebb and flow of the seas and oceans is? Every day the water leaves the shores, it is not known where it hangs for several hours, and then, as if nothing had happened, it returns back.
So the water at this time is not unknown where, but approximately in the middle of the ocean. There, something like a mountain is formed from water. Incredible, right? Water, which tends to spread, does not just flow itself down, but also forms mountains. And in these mountains a huge mass of water is concentrated.
Just estimate the entire volume of water that leaves the coast during low tides, and you will understand that we are talking about gigantic quantities. But since this happens, there must be some reason. And there is a reason. The reason lies in the fact that this water is attracted to the Moon.
Orbiting the Earth, the Moon passes over the oceans and attracts the oceanic waters. The moon revolves around the earth because it is attracted by the earth. But, it turns out that she herself at the same time attracts the Earth to herself. The land, however, is too big for her, but its influence is sufficient to move water in the oceans.
Force and the law of universal gravitation: concept and formula
Now let's go ahead and think: if two huge bodies, being nearby, both attract each other, is it not logical to assume that smaller bodies will also attract each other? Are they just much smaller and the force of their attraction will be small?
It turns out that this assumption is absolutely correct. Absolutely between all bodies in the Universe, there are forces of attraction, or, in other words, the forces of universal gravity.
Isaac Newton was the first to discover and formulate such a phenomenon in the form of a law. The law of universal gravitation says: all bodies are attracted to each other, while the force of their attraction is directly proportional to the mass of each of the bodies and inversely proportional to the square of the distance between them:
F = G * (m_1 * m_2) / r ^ 2,
where F is the magnitude of the vector of the force of attraction between the bodies, m_1 and m_2 are the masses of these bodies, r is the distance between the bodies, G is the gravitational constant.
The gravitational constant is numerically equal to the force that exists between bodies of mass 1 kg, located at a distance of 1 meter. This value was found experimentally: G = 6.67 * 〖10〗 ^ (- 11) N * m ^ 2⁄ 〖kg〗 ^ 2.
Returning to our original question: "are we pulling the Earth?", We can confidently answer: "yes." According to Newton's third law, we attract the Earth with exactly the same force with which the Earth attracts us. This force can be calculated from the law of universal gravitation.
And according to Newton's second law, the action of bodies on each other by any force is expressed in the form of the acceleration they impart to each other. But the acceleration imparted depends on the body weight.
The mass of the Earth is great, and it gives us the acceleration of free fall. And our mass is negligible compared to the Earth, and therefore the acceleration that we give to the Earth is practically zero. That is why we are attracted to the Earth and walk on it, and not vice versa.
Sir Isaac Newton, having received an apple on the head, deduced the law of universal gravitation, which reads:
Any two bodies are attracted to each other with a force directly proportional to the product of body masses and inversely proportional to the square of the distance between them:
F = (Gm 1 m 2) / R 2, where
m1, m2- body masses
R- the distance between the centers of the bodies
G = 6.67 10 -11 Nm 2 / kg- constant
Let's define the acceleration of gravity on the surface of the Earth:
F g = m body g = (Gm body m Earth) / R 2
R (radius of the Earth) = 6.38 10 6 m
m Earth = 5.97 10 24 kg
m body g = (Gm body m Earth) / R 2 or g = (Gm of the Earth) / R 2
Please note that the acceleration due to gravity is independent of body weight!
g = 6.67 10 -11 5.97 10 24 / (6.38 10 6) = 398.2 / 40.7 = 9.8 m / s 2
We said earlier that the force of gravity (gravitational attraction) is called weight.
On the surface of the Earth, weight and body mass have the same meaning. But with distance from the Earth, the weight of the body will decrease (since the distance between the center of the Earth and the body will increase), and the mass will remain constant (since mass is an expression of the body's inertia). Mass is measured in kilograms, weight - in newtons.
Due to the force of gravity, celestial bodies rotate relative to each other: the Moon around the Earth; Earth around the Sun; The sun is around the center of our Galaxy, etc. In this case, the bodies are held by centrifugal force, which is provided by the force of gravity.
The same applies to artificial bodies (satellites) orbiting the Earth. The circle around which the satellite rotates is called the orbit of rotation.
In this case, a centrifugal force acts on the satellite:
F c = (m satellite V 2) / R
Gravity:
F g = (Gm of satellite m of the Earth) / R 2
F c = F g = (m satellite V 2) / R = (Gm satellite m Earth) / R 2
V2 = (Gm Earth) / R; V = √ (Gm Earth) / R
Using this formula, you can calculate the speed of any body rotating in an orbit with a radius R around the Earth.
The natural satellite of the Earth is the Moon. Let's define its linear velocity in orbit:
Earth mass = 5.97 10 24 kg
R is the distance between the center of the Earth and the center of the Moon. To determine this distance, we need to add three quantities: the radius of the Earth; the radius of the moon; distance from the Earth to the Moon.
R moon = 1738 km = 1.74 10 6 m
R land = 6371 km = 6.37 10 6 m
R PLN = 384 400 km = 384.4 10 6 m
The total distance between the centers of the planets: R = 392.5 10 6 m
Linear velocity of the moon:
V = √ (Gm of the Earth) / R = √6.67 10 -11 5.98 10 24 / 392.5 10 6 = 1000 m / s = 3600 km / h
The moon moves in a circular orbit around the Earth with a linear velocity of 3600 km / h!
Let us now determine the period of the Moon's revolution around the Earth. During the period of revolution, the Moon overcomes a distance equal to the length of the orbit - 2πR... Moon's orbital speed: V = 2πR / T; on the other side: V = √ (Gm Earth) / R:
2πR / T = √ (Gm of the Earth) / R hence T = 2π√R 3 / Gm of the Earth
T = 6.28 √ (60.7 10 24) / 6.67 10 -11 5.98 10 24 = 3.9 10 5 s
The period of the Moon's revolution around the Earth is 2,449,200 seconds, or 40,820 minutes, or 680 hours, or 28.3 days.
1. Vertical rotation
Earlier in circuses it was a very popular trick in which a cyclist (motorcyclist) made a full revolution inside a circle located vertically.
What is the minimum speed a trick should have in order not to fall down at the top point?
To pass the top point without falling, the body must have a speed that creates such a centrifugal force that would compensate for the force of gravity.
Centrifugal force: F c = mV 2 / R
Gravity: F g = mg
F c = F g; mV 2 / R = mg; V = √Rg
Again, note that body weight is missing from the calculations! It should be noted that this is the speed that the body should have at the top point!
Let's say that a circle with a radius of 10 meters is set in the circus arena. Let's calculate the safe speed for the trick:
V = √Rg = √10 9.8 = 10 m / s = 36 km / h