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The paper examines and critiques the expression of entropy as the logarithm of the number of quantum states of a physical system. Boltzmann method of expressing entropy as the logarithm of the number of states of a gas with a given total energy is analyzed. We demonstrate that entropy is the product of subquantum processes and show that entropy is expressed as the ratio of the logarithm of the maximum number of realizations, over the observation period, of a macroscopic system's states with a given total energy, to the number of occurrences of its quantum states over this time.

One of the main challenges associated with the implementation of an Open RAN User-Centric Cell-Free network is the appropriate formulation of serving clusters. This problem can be effectively solved using a proposed algorithm that leverages cooperation between xApp and rApp. Simulation results have shown that the proposed solution allows for a 16% increase in the median of the user throughput distribution compared to the state-of-the-art network-centric architecture

In the last few years, a very original concept of holographic communication has gained a lot of interest among scientists from all over the world. The specificity of this approach, on the one hand, is very different from the known and currently used solutions, on the other hand, it creates great development opportunities in the field of wireless communication. The article provides an overview of two technological solutions that gave rise to the idea of holographic communication. First, the possibility of using the so-called metamaterials for the purposes of wireless data transmission, and the second, the use of reconfigurable antenna surfaces. The last part presents the assumptions of the idea of holographic communication, in which the principles of creating images known from optical holography have been transferred to the radio band, and to some extend, generalized.

Drony, dzięki możliwości ich szybkiego rozmieszczenia w trudnym terenie, uważane są za jeden z kluczowych elementów systemów bezprzewodowych 6G. Jednak w celu wykorzystania ich jako punkty dostępowe sieci konieczne jest zapewnienie łącza dosyłowego o odpowiedniej przepustowości. Dlatego w niniejszym artykule rozważane jest zwiększenie zasięgu sieci bezprzewodowej przez zapewnienie łącza dosyłowego dla końcowego punktu dostępowego z wykorzystaniem określonej liczby dronów-przekaźników oraz rekonfigurowalnych inteligentnych matryc antenowych (RIS). Zaprezentowane wyniki badań symulacyjnych pokazują, że użycie RIS pozwala na znaczące zwiększenie zasięgu sieci bez konieczności stosowania dodatkowych przekaźników. -- Unmanned Aerial Vehicles, due to the possibility of their fast deployment, are considered an essential element of the future wireless 6G communication systems. However, an essential enabler for their use as access points is to provide a sufficient throughput wireless backhaul link. Thus, in this paper we consider the aspect of extension of network coverage with the use of drone-based relaying and reconfigurable intelligent surfaces (RIS) for backhauling. Presented results o

Twisted bilayer graphene (TBG) near the magic twist angle of $\sim1.1^{o}$ exhibits a rich phase diagram. However, the interplay between different phases and their dependence on twist angle is still elusive. Here, we explore the stability of various TBG phases and demonstrate that superconductivity near filling of two electrons per moiré unit cell alongside Fermi surface reconstructions, as well as entropy-driven high-temperature phase transitions and linear-in-T resistance occur over a range of twist angles which extends far beyond those exhibiting correlated insulating phases. In the vicinity of the magic angle, we also find a metallic phase that displays a hysteretic anomalous Hall effect and incipient Chern insulating behaviour. Such a metallic phase can be rationalized in terms of the interplay between interaction-driven deformations of TBG bands leading to Berry curvature redistribution and Fermi surface reconstruction. Our results provide an extensive perspective on the hierarchy of correlated phases in TBG as classified by their robustness against deviations from the magic angle or, equivalently, their electronic interaction requirements.

In the presence of a large perpendicular electric field, Bernal-stacked bilayer graphene (BLG) features several broken-symmetry metallic phases as well as magnetic-field-induced superconductivity. The superconducting state is quite fragile, however, appearing only in a narrow window of density and with a maximum critical temperature $T_c\approx30$~mK. Here, we show that placing monolayer tungsten diselenide (WSe$_{2}$) on BLG promotes Cooper pairing to an extraordinary degree: superconductivity appears at zero magnetic field, exhibits an order of magnitude enhancement in $T_c$, and occurs over a density range that is wider by a factor of eight. By mapping quantum oscillations in BLG-WSe$_2$ as a function of electric field and doping, we establish that superconductivity emerges throughout a region whose normal state is polarized, with two out of four spin-valley flavours predominantly populated. In-plane magnetic field measurements further reveal a striking dependence of the critical field on doping, with the Chandrasekhar-Clogston (Pauli) limit roughly obeyed on one end of the superconducting dome yet sharply violated on the other. Moreover, the superconductivity arises only for pe

Researchers have achieved a major milestone by creating a long-sought two-dimensional quantum material and confirming its unusual conducting edge states。 The ability to control these states through strain could make the material a promising platform for future room-temperature quantum electronics

Scientists have identified new clues that could help astronomers spot one of the most famous hypothetical alien megastructures: a Dyson sphere。 The study finds that red dwarfs and white dwarfs are the most promising stars to examine, since advanced civilizations could potentially build energy-harvesting swarms around them more easily。 These objects

Water’s odd behavior becomes even more dramatic when it is supercooled, but scientists have struggled to compare the many different ways of describing its microscopic structure。 Researchers at the University of Osaka used an AI model trained on computer simulations to evaluate 16 different structural descriptors。 The system identified the most effe

Celebrating the United States' 250th anniversary, NASA released a stunning Hubble portrait of Messier 3, an ancient globular cluster with more than 500,000 stars。 The remarkable cluster is helping scientists unravel the Milky Way's past thanks to its rare stars and possible origins in a long ago cosmic merger

There's a separate $1,750 rebate for used EVs, but both rebates have a price cap

A new study suggests the brain begins making decisions much earlier than scientists previously thought。 Researchers found that even primary sensory regions are influenced by higher brain areas through rapid feedback loops, rather than simply passing information forward。 This more dynamic view of brain function could help engineers design future AI

Astronomers have released the largest gravitational wave catalog ever, revealing 161 new black hole collisions and pushing the total number of detections to 390。 Among the highlights are the clearest gravitational wave signal ever recorded, the most accurate location of a black hole merger, and growing evidence that some black holes are the product

AG: Deal will bring "higher prices, lower quality, and less content for film and TV

A newly developed material can control and "program" heat, allowing it to direct thermal radiation, switch modes, and remember its settings without continuous power。 The innovation could lead to smarter infrared sensors, better energy technologies, and memory devices that use light and heat instead of electrical charges

"If we can't control the force of nature, at least we can control the narrative

Reinforcement learning uses error information to adjust control algorithms

Hubble has captured a spectacular view of LH 95, where about 2,500 young stars are still on their journey to becoming full-fledged stars。 Scientists discovered these growing stars can keep pulling in gas and dust for millions of years, extending an important stage of stellar development。 The region also contains multiple generations of stars living

Scientists have developed a new framework that could finally apply the laws of thermodynamics to real, ever-changing black holes instead of only perfectly stable ones。 The advance may improve our understanding of black hole mergers, evaporation, and the powerful gravitational wave events detected by observatories like LIGO