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Well have to invent a new cosmology Physicists question the Well have to invent a new cosmology Physicists question the

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“We’ll have to invent a new cosmology.” Physicists question the theory of gravity

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Scientists have found that the structure of star clusters closest to the Earth contradicts Newton’s laws and Einstein’s general theory of relativity, but at the same time confirms one of the alternative concepts of gravity, which denies dark matter. This is a challenge to the whole system of views on how the Universe works.

Well have to invent a new cosmology Physicists question the

Gravitational waves

The assumption of the existence of a substance that cannot be detected was first made 89 years ago by the Swiss astronomer Fritz Zwicky. He showed that at the speed with which the galaxies are moving, they should fly apart, but this does not happen.

Therefore, there is still some mass. Zwicky called it dark matter. According to calculations, there is much more of it in the Universe than usual. But it does not reflect, absorb, or emit light, making it invisible in any part of the electromagnetic spectrum.

For several decades, this hypothesis was hardly remembered – until the American astronomers Vera Rubin and Kent Ford revealed the same pattern inside the spiral galaxy Andromeda Nebula (M31), and then in dozens of other spiral galaxies, including the Milky Way. This happened in 1970.

According to Keplerian mechanics, the speed of stars should decrease with distance from the galactic center. But it turned out that the stars in the center and on the periphery of spiral galaxies move approximately the same way. As if they were connected by some kind of framework, a grandiose cloud with a colossal mass. Scientists have suggested that particles of an unknown nature, inaccessible to direct observation, are involved in the formation of galactic gravitational fields. The same dark matter Zwicky.

Despite numerous experimental efforts, there is still no direct evidence for its existence. Nevertheless, physicists actively use this hypothesis to explain many cosmic phenomena: gravitational lensing – the curvature of light coming from distant stars, the temperature distribution of hot gas in galaxies, the anisotropy of the microwave background, and others.

In all these cases, we are talking about deviations from the classical theory of gravity. However, there are those who believe that all inconsistencies can be removed. There have been hundreds of attempts to create alternative theories.

Modified Newtonian dynamics (MOND) model was developed in 1982 by Israeli physicist Mordechai Milgrom. He suggested that the acceleration depends nonlinearly on the mass and for small accelerations the law of universal gravitation does not apply. The movement is determined not only by its own mass, but also by the mass of surrounding objects – this is the so-called external field effect.

An international team of scientists led by Pavel Krupa from the University of Bonn recently published the results of a study of stars in clusters in the journal Monthly Notices of the Royal Astronomical Society.

We are talking about the five clusters closest to Earth: Hyades, Manger, Coma Berenices, NGC 752 and COIN-Gaia 13. All of them consist of young stars formed from clouds of dust and gas. According to astronomical data, as they move, such clusters lose stars under the influence of galactic gravity.

Tidal tails form at the edges of clusters, long, thin structures of stars and gas ahead and behind as they travel. According to the classical theory of gravity, both tails must be the same.

According to Newton’s laws of gravity, which tail a lost star ends up in is a matter of chance.”, – says one of the authors of the study, Dr. Jan Pflamm-Altenburg.

However, in all clusters in the forward tails, which are closer to the center of the galaxy, there are more stars than in the rear ones. The distribution fits well into MOND, which assumes that gravity at low accelerations is stronger than it follows from Newton’s laws.

Simply put, according to MOND, stars can leave the cluster through two different doors. One leads to the rear tidal tail, the other to the front. According to Newton, both doors must be the same. In fact, the first is much narrower than the second.”, explains Professor Krupa.

In addition, the real lifetime of scattered constellations does not exceed 50 percent of that calculated by the classical gravitational model. MOND suggests that an excess of stars in the forward tail causes the cluster to slow down and rotate around the center of the galaxy in an increasingly elongated orbit, while spinning in the opposite direction of the orbital rotation, which leads to accelerated decay.

Other MOND confirmations have been pointed out previously. In particular, in 153 different galaxies, a nonlinear dependence of the orbital velocity of stars and gas on the distance to the galactic center was recorded. According to scientists, this may be due to the effect of an external field, due to which objects in strong gravitational fields slow down more than in weak ones. With this approach, it is not required to explain the stability of dark matter.

Nevertheless, the authors of the study themselves admit that the alternative theory of gravity explains only a limited range of phenomena and should be treated very carefully.

More than a few twisted star clusters are needed to prove it. If the theory is correct, all calculations regarding the formation, movement of galaxies and their interaction with each other are incorrect. We’ll have to invent a new cosmology”, emphasizes Krupa.

In the meantime, most of the facts still point to dark matter. And the processes in the Universe are most successfully described by Einstein’s general theory of relativity (GR), postulating that gravitational and inertial forces have the same nature. Hence it follows that gravitational effects are caused not by the force interaction of bodies and fields located in space-time, but by the deformation of space-time itself, which is associated, in particular, with the presence of mass-energy.

The most important confirmation of general relativity is the experimental detection in 2016 of gravitational waves generated by the collision of two neutron stars. In 2017, the Nobel Prize in Physics was awarded for this discovery.

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Latest Dimensity 8200 and 120W charger. iQOO Neo 7 SE parameters became known

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Latest Dimensity 8200 and 120W charger iQOO Neo 7 SE

The iQOO Neo 7 SE smartphone, which will be presented on December 2, will receive a very productive platform, albeit not a flagship level.

Latest Dimensity 8200 and 120W charger.  iQOO Neo 7 SE parameters became known

Thanks to the TENAA base, it became known that the new product will be equipped with the Dimensity 8200 SoC, which has not yet been presented. Also, the device will receive a battery with a capacity of 5000 mAh with 120-watt charging. As you can see, this level of charging is becoming more common in mid-range smartphones.

Of course, we do not yet know the prices of iQOO Neo 7 SE, but iQOO Neo 6 SE started at $390. By the way, this device also offered optical stabilization for the main camera, so you can expect it in the novelty.

iQOO Neo 7 SE should also get a 6.78-inch AMOLED screen, 8 to 16 GB of RAM, 128 to 512 GB of flash memory and a 64-megapixel main camera.

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Will the GeForce GTX 1660 Ti stay for at least another year? Nvidia is ending production of almost all mid-range graphics cards.

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Will the GeForce GTX 1660 Ti stay for at least

Nvidia has decided to completely stop the production of several models of video cards of past generations.

Will the GeForce GTX 1660 Ti stay for at least another year?  Nvidia is ending production of almost all mid-range graphics cards.

We are talking about the GeForce RTX 2060 Super, RTX 2060, GTX 1660 Super and GTX 1660 cards. The source does not have any details, but we already know that there is an RTX 3050 to replace the RTX 2060/2060 Super, but the GTX 1660 cards there are simply no replacements. The source doesn’t mention the GTX 1660 Ti, though, so it’s possible Nvidia is keeping this card alone to close the hole in the sub-$300 segment.

In particular, in Europe now for the GTX 1660/1660 Super/1660 Ti they are asking for about the same money: from about 230-240 euros. At the same time, the cheapest RTX 3050 now costs 300 euros. No more affordable cards will appear in the RTX 30 line, and it’s not worth waiting for cheap RTX 40 cards in the foreseeable future, because even the RTX 4060 is supposedly released only next summer.

For comparison, AMD has a modern Radeon RX 6600 in the sub-$300/Euro segment, which is much more powerful than any GTX 1660, and along with the RTX 3050.

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Mutny Continent hosted mobile internet for the first time

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Mutny Continent hosted mobile internet for the first time

VimpelCom (trademark Beeline) announced that it has become the first and currently the only operator that has built infrastructure and launched cellular mobile communications in the village of Mutny Materik.

Mutny Continent hosted mobile internet for the first time

“Mudny Mainland” is a remote settlement in the Komi Republic, the distance to the nearest city is almost 300 km. As part of expanding Beeline network coverage in the region, the operator launched 4G in this village as well. Previously, only voice calls were available to a population of about 900 people, and even then, not cellular, but through Beeline satellite communication channels.

As the operator notes, the launch of cellular communication was complicated not only by the remoteness of the village from other settlements, but also by its inaccessibility. “Mudny Continent” is located on the banks of the Pechora River, it can be reached in the warm season only by water transport or by helicopter, and in the cold season along a temporary road – a winter road.

Director of the Syktyvkar branch of Beeline Konstantin Ikonnikov noted:

Communication is now one of the vital needs, and the mobile Internet allows you to quickly resolve many important issues and gain access to digital services, such as government services. Understanding what social task we are performing, Beeline is building a network even in the most remote and hard-to-reach corners of the Komi Republic and the whole country, despite the rather harsh climate and vast distances. Developing communication in such conditions is always a challenge that we cope with, and the launch of 4G Internet in the village of Mutny Mainland is another confirmation of this.

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