Some time ago the attention of the scientific community was drawn to an article by the Russian physicist Nikolai Garkavogo in which he questioned the existence of the Universe, the so-called dark energy. Dark energy is not found until now, the substance considered to be responsible for the accelerated recession of the Universe. In the modern astrophysical concept of dark energy to explain the accelerated expansion of the Universe many astrophysicists are trying to find traces of it, under such projects are allocated a lot of money. Nicholas gorkavyy, a graduate of Chelyabinsk state University, now Director, senior researcher Greenwich private scientific and technological Institute, Virginia (USA), in his article published in the journal MNRAS, the considered solution of the Einstein equations for collapsing Universe and came to the conclusion that due to the decrease in the total gravitational mass due to the emission of gravitational waves in such a system occurs a repulsive force which can transform the contraction of the Universe in the Big Bang.
Thus, says the author, observed rapid divergence of the Universe can be explained without involving mysterious substances like dark energy.
“This means that the accelerated expansion of the Universe is not a modern condition, and relic gravitational fields encountered in the process of Large strain,” explained the author in his blog, where he began a serious debate between supporters and critics of the work.
“Газета.Ru” talked with the author of the work, and took a comment from his opponent in order to understand whether early scientists to bury the dark energy.
— Nikolay Nikolaevich, can we assume that my assumption you bury the dark energy? And what are the arguments of the critics of your idea?
“I suppose it is. In our work it is shown that when the universe collapses into a compact volume and pumping their mass into gravitational radiation, then there is a strong repulsive or antigravity, the force is with absolutely transparent physics that can understand and student. Antigravity weakens over time, but remains at least ten billion years, and that is exactly what was missing to explain the accelerated expansion of the Universe.
This is simply the result of the General theory of relativity, which requires you to enter a fantastic antigravitons substance
Oxford University Orget the gravitational potential is often illustrated by a funnel from the rubber film, which stretches the heavy ball located in the center. In this simple model the sharp decrease of the gravitational mass corresponds to the rapid rise of the ball. Film attached to the ball, pulled the cone-shaped peak in the center of the crater. Light bulbs in the Central cone will rush from the center – this is a strong antigravity.
and to build cosmological models based on Einstein found repelling force. I wonder what causes the curvature of space that causes the observed acceleration of the Universe, is completely absent at present. Imagine that somewhere near Australia on the gentle wave tsunami slide surfers. Around no hurricane, no storm, and the cause of the wave is the earthquake that happened long ago and far away, somewhere near Alaska. And the present cosmological acceleration is set to the gravitational field, or, more precisely, space-time curvature, which originated with the collapse of the Universe of the previous cycle.
On the criticism. In the discussion of the article, it has been suggested that our decision violates the Birkhoff theorem, which forbids the existence of a non-stationary spherically symmetric gravitational field. But we pointed out with reference to known works that in the present case, there are emitters of gravitational waves, which immediately violates the strict spherical symmetry and Birkhoff’s theorem does not apply to our case. Frankly, I do not hope for serious criticism against exact solutions of Einstein’s equations it is difficult to argue, much easier to pretend that nothing happened
and enthusiastically to continue to drive articles about dark energy, which now publishes more than thousands per year.
— A fundamental condition for the emergence of repulsive forces — the reduction of the gravitational mass of the system (in this case the Universe). The mass decreases because the gravitational waves carry energy, and E=m*c<sup>2</sup>. But why in this case this formula does not work in the opposite direction and does not allow to calculate the mass of gravitational waves”? Where does the mass of the Universe?
In the famous equation E=m*c<sup>2</sup> is an inert mass. And in our work, we consider gravitational mass. If inertial mass and energy impose strict conditions such as conservation laws, there are no fundamental constraints on the variability of gravitational mass is not. I have often had to give such explanations, and educated listener in this place usually had no exact equality of gravitational and inertial masses is proved in the experiments of eötvös and taken by Einstein as the basis of his theory as the principle of equivalence. Have to explain the subtleties: there are four types of mass
passive inertial and passive gravitational, and active inert and active gravitational.
A lot? Now reduce. When the ball falls to the ground, then it is valid M1*g — the gravitational force, which is the passive mass m, which responds to gravity. The acceleration g contains the active mass of the Earth generates gravity. The force of inertia M2*a, which is valid on the falling ball (because M2*a=M1*g), is a passive inert mass. Einstein took eötvös experimentally proved by the equality of passive inertial and passive gravitational mass (or equality of acceleration g= a*M2/M1 for each of the considered bodies of different materials) and took him to the manifestation of iskrivlennoi the space in which the different bodies move on the same trajectories as different trains on one track. Thus Einstein, using the equality of passive gravitational and passive inert mass, removed from his the theory of these concepts, made them fictitious. In General relativity, remained the only active mass, inert, part of the E=m*c<sup>2</sup>, and gravity that is the source of the curved space. At the same time the gravitational field and gravitational waves Einstein did not include the sources in the curved space.
— In your scenario the universe is starting to expand, currently has only one giant black hole. This is consistent with the idea of the hot Universe, confirmed the same observations of the cosmic microwave background? Like in the Universe where there are only black holes, arose the rest?
— Our article is devoted not cosmology, and the discussion of the repelling force of Einstein’s theory. But for example, we used the simplest model of the Universe consisting of black holes. For more realistic models need to include at least electromagnetic radiation. My co-author Alexander Vassilkov, skilled theoretician, graduated from MIPT, which asks questions the nail on the head, reflect on this model of the Universe. If you take all the light quanta issued by the stars of the previous Universe for tens of billions of years, and then squeeze them into a small volume, the energy density that grows like 1/R<sup>4</sup>, will be incredible. Collapsing universe will be a bunch of gamma rays fantastic energy mixed with black holes. When the total mass of the black holes will fall sharply and there is antigravity tsunami, this bundle of electromagnetic energy to explode in all directions, increasing its energy and anti-gravity potential.
Such a process would look like the big Bang. But it is you climbed in a future article.
— It turns out your theory is to describe the current expansion (and its acceleration) of the Universe quantitatively? Is it possible to say something about the parameters of a previous Universe required for that impulse that we see today?
— In our article is not based cosmological model, it discusses a more basic level — the presence in the theory of gravitation of Einstein’s antigravity. The Einstein equation in the approximation of weak field had two known solutions: gravitational waves and the Newtonian law of gravity to constant weight. We got a third solution: the law of gravity for variable mass in which there was antigravity. Quantitative assessment applied to the Universe show that antigravity can exceed gravity even for those times when the universe was very compressed. But quantitative cosmological model that takes into account the possibility of antigravity, not yet built. On the last cycle while it is possible to say that at the end of compression of a previous Universe black holes constituted a significant share of its mass. In addition, there was a strong background of gravitational radiation.
The article suggests that our universe could be filled with high frequency (e.g., gigahertz) gravitational radiation carried over from a previous cycle of the Universe. There is great energy that is contained in this radiation? Can we measure it? I hope that soon we will know the answers to these questions and finally understand the world in which they live.
I’m sure we’ll find amazing discoveries and surprises. Perhaps, practically useful.
Pavel Ivanov, a leading researcher of Astro space center of Physical Institute. P. N. Lebedev of RAS, doctor of physico-mathematical Sciences:
— Paul Miller, the authors of this work claim the possibility of solving the dark energy problem. You as an expert agree that the result is really possible to accept?
— I strongly disagree and believe that the result is obtained, first, as a result of incorrect calculation and, secondly, from my point of view, from gravitational waves to do something that may be a candidate for dark energy, in principle, impossible. There’s a theorem: roughly speaking, to certain substance called an expanding Universe with acceleration (what there is now), she must have unusual properties. First, the pressure of this substance, which has the same units as the energy density must be negative and, taken with the negative sign, must not exceed the energy density divided by three. Then violated the so-called strong energy condition. Various scalar fields used in cosmology, this condition have, and gravitational waves, at least classic.
And what would gorkavyy nor figured, from my point of view, this theorem he can not violate.
The second part of the criticism is based on the fact that the calculation carried out by the author, is incorrect. It is not considered members of the same order of smallness as the term to the equation which he interpreted as giving the antigravity. This expression correctly, since its output was not taken into account the contribution of those gravitational waves emitted by the source.
There is a rigorous theorem: if we consider empty without material bodies and growan space-time, which has spherical symmetry, it is nothing but the well-known Schwarzschild solution, can not be. This is the theorem of Birkhoff.
And if you want to obtain a new substance, say anti-gravity, you’ll either have to break spherical symmetry, or space-time should be filled with some kind of matter. Have Garkavogo the role this material played flowing from the source of gravitational waves, which are themselves also can gravitate. So the contributions of gravitational waves in accelerating the author has not calculated taking into account only the contribution from the source.
It can be shown that the contribution he considered, is of the same order of smallness as the contribution from grewan that he did not realize. Although, generally speaking, it is my contention, too, must prove, to write comments in the same magazine, and more.
And here he is right when he says: if you want to refute me — down formula.
— As an argument in their favor (almost basic), the authors say that just found a solution to the Einstein equations under certain initial conditions. With the equations of General relativity is really hard to argue. But is it possible to argue with the formulation and interpretation of the obtained solution?
— What they found is not the exact solution. There are a lot of approximations, in particular, from my point of view, infidels. Roughly speaking, he took the well-known expression for the metric at large distances from a weak source of gravitational radiation and wrote one member, claiming that the rest is insignificant to the power of spherical symmetry. The task itself from a technical point of view incorrectly decided, it should be solved in new ways, maybe I’ll do it or another person will pay attention to this task.
“But in the scientific world there are a large number of the defenders of the dark energy, it allocated huge amounts of money, you assume that this substance may not be and antigravity can be derived from the Einstein equations?
— I believe in dark energy, from my point of view, its existence is a solid fact.
This is possible, but you need to modify the very theory of gravity. In fact, this has already been done in the model Starobin, and it is expanding with acceleration — however, in the early stages of the Universe.
