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Our proposed cosmological framework, which is based on fractional quantum cosmology, aims to address the issue of synchronicity in the age of the universe. To achieve this, we have developed a new fractional ΛCDM cosmological model. We obtained the necessary formalism by obtaining the fractional Hamiltonian constraint in a general minisuperspace. This formalism has allowed us to derive the fractional Friedmann and Raychaudhuri equations for a homogeneous and isotropic cosmology. Unlike the traditional de Sitter phase, our model exhibits a power-law accelerated expansion in the late-time universe, when vacuum energy becomes dominant. By fitting the model’s parameters to cosmological observations, we determined that the fractional parameter of Lévy equals α=1.986. Additionally, we have calculated the age of the universe to be 13.8196 Gyr. Furthermore, we have found that the ratio of the age to Hubble time from the present epoch to the distant future is finite and confined within the interval 0.9858≤Ht<95.238.

This paper is a comment on both Bunamano and Rovelli (Bridging the neuroscience and physics of time arXiv:2110.01976. (2022)) and Gruber et al. (in Front. Psychol. Hypothesis Theory, 2022) and which discuss the relation between physical time and human time. I claim here, contrary to many views discussed there, that there is no foundational conflict between the way physics views the passage of time and the way the mind/brain perceives it. The problem rather resides in a number of misconceptions leading either to the representation of spacetime as a timeless Block Universe, or at least that physically relevant universe models cannot have preferred spatial sections. The physical expanding universe can be claimed to be an Evolving Block Universe with a time-dependent future boundary, representing the dynamic nature of the way spacetime develops as matter curves spacetime and spacetime tells matter how to move. This context establishes a global direction of time that determines the various local arrows of time. Furthermore time passes when quantum wave function collapse takes place to an eigenstate; during this process, information is lost. The mind/brain acts as an imperfect clock, which coarse-grains the physical passage of time along a world line to determine the experienced passage of time, because neural processes take time to occur. This happens in a contextual way, so experienced time is not linearly related to physical time in general. Finally I point out that the Universe is never infinitely old: its future endpoint always lies infinitely faraway in the future.

In this research, we are interested in constraining the nonlinear interacting and noninteracting Tsallis holographic dark energy (THDE) with Ricci horizon cutoff by employing three observational datasets. To this aim, the THDE with Ricci horizon considering the noninteraction and nonlinear interaction terms will be fitted by the SNe Ia, SNe Ia+H(z), and SNe Ia+H(z)+GRB samples to investigate the Hubble (H(z)), dark-energy equation of state (ωDE), effective equation of state (ωeff), and deceleration (q) parameters. Investigating the H(z) parameter illustrates that our models are in good consistency with respect to observations. Also, it can reveal the turning point for both noninteracting and nonlinear interacting THDE with Ricci cutoff in the late-time era. Next, the analysis of the ωDE for our models displays that the dark energy can experience the phantom state at the current time. However, this lies in the quintessence regime in the early era and approaches the cosmological constant in the late-time epoch. Similar results will be given for the ωeff parameter with the difference that the ωeff will experience the quintessence region at the current redshift. In addition to the mentioned parameters, the study of the q parameter indicates that the models satisfy an acceptable transition phase from the matter- to the dark energy-dominated era. After that, the classical stability (vs2) will be analyzed for our models. The vs2 shows that the noninteracting and nonlinear interacting THDE with Ricci cutoff will be stable in the past era but unstable in the present and progressive epochs. Then, we will employ the Jerk (J) and OM parameters to distinguish between our models and the ΛCDM model. Finally, we will calculate the age of the Universe for the THDE and nonlinear interacting THDE with Ricci as the IR cutoff.

This book provides a comprehensive, self-contained introduction to one of the most exciting frontiers in astrophysics today: the quest to understand how the oldest and most distant galaxies in our universe first formed. Until now, most research on this question has been theoretical, but the next few years will bring about a new generation of large telescopes that promise to supply a flood of data about the infant universe during its first billion years after the big bang. This book bridges the gap between theory and observation. It is an invaluable reference for students and researchers on early galaxies. The First Galaxies in the Universestarts from basic physical principles before moving on to more advanced material. Topics include the gravitational growth of structure, the intergalactic medium, the formation and evolution of the first stars and black holes, feedback and galaxy evolution, reionization, 21-cm cosmology, and more. Provides a comprehensive introduction to this exciting frontier in astrophysicsBegins from first principlesCovers advanced topics such as the first stars and 21-cm cosmologyPrepares students for research using the next generation of large telescopesDiscusses many open questions to be explored in the coming decade

The present work is focused on the study of locally rotationally symmetric Bianchi type-II model with perfect fluid in f(R, T) gravity. Three types of f(R, T) gravity models are proposed (Harko et al. in Phys Rev D 84:024020, 2011). According to the first model, the function f(R,T)=R+2f(T), where R is Ricci scalar and f(T) is an arbitrary function of trace of stress energy tensor T. In this paper, the function f(T)=αT+βT2 is considered, where α and β are real numbers. The physical parameters are determined with respect to cosmic time as well as red shift by using the equation of state p=ϵρ and the scale factor a(t)=(sinh(ϕt))1k, where k>0 & ϕ≠0. The energy density is compared for dust and radiation-dominated models. The present values of deceleration parameter, Hubble parameter and age of the universe are determined and compared with the results of ΛCDM model. Further, the theoretical and experimental values of luminosity distance and apparent magnitude are compared.

From our exact solution of the Janus Cosmological equation we derive the relation of the predicted magnitude of distant sources versus their red shift. The comparison, through this one free parameter model, to the available data from 740 distant supernovae shows an excellent fit.

We investigate a spatially flat Friedmann–Robertson–Walker scenario with two interacting components, dark matter and variable vacuum energy densities, plus two decoupled components, one is a baryon term while the other behaves as a radiation component. We consider a linear interaction in the derivative dark component density. We apply the χ2 method to the observational Hubble data for constraining the cosmological parameters and analyze the amount of dark energy in the radiation era for the model. It turns out that our model fulfills the severe bound of Ωx(z≃1,100)<0.009 at 2σ level, so is consistent with the recent analysis that include cosmic microwave background anisotropy measurements from Planck survey, the future constraints achievable by Euclid and CMBPol experiments, reported for the behavior of the dark energy at early times, and fulfills the stringent bound Ωx(z≃1010)<0.04 at 2σ level in the big-bang nucleosynthesis epoch. We also examine the cosmic age problem at high redshift associated with the old quasar APM 08279+5255 and estimate the age of the universe today.

A result of calculation of the topological properties of the Universe and its large-scale substances is presented. An equation for calculating values of the Hubble constant of the substances of the Universe, and of the Universe and the Galaxy, Sun, and Earth has been obtained for the first time. Their age and the time of one full cycle and of five cycles of expansion and compression of the Universe are calculated. A new hypothesis about the formation of the relic background of the Universe is proposed. The infinity of its evolution in time is proven .

Recently, we published two papers in this journal. One of the papers dealt with the action of the radiation fields generated by a traveling-wave element and the other dealt with the momentum transferred by the same radiation fields and their connection to the time energy uncertainty principle. The traveling-wave element is defined as a conductor through which a current pulse propagates with the speed of light in free space from one end of the conductor to the other without attenuation. The goal of this letter is to combine the information provided in these two papers together and make conclusive statements concerning the connection between the energy dissipated by the radiation fields, the time energy uncertainty principle and the elementary charge. As we will show here, the results presented in these two papers, when combined together, show that the time energy uncertainty principle can be applied to the classical radiation emitted by a traveling-wave element and it results in the prediction that the smallest charge associated with the current that can be detected using radiated energy as a vehicle is on the order of the elementary charge. Based on the results, an expression for the fine structure constant is obtained. This is the first time that an order of magnitude estimation of the elementary charge based on electromagnetic radiation fields is obtained. Even though the results obtained in this paper have to be considered as order of magnitude estimations, a strict interpretation of the derived equations shows that the fine structure constant or the elementary charge may change as the size or the age of the universe increases.

The P-NP problem is the most important open problem in computer science, if not all of mathematics.The Golden Ticketprovides a nontechnical introduction to P-NP, its rich history, and its algorithmic implications for everything we do with computers and beyond. In this informative and entertaining book, Lance Fortnow traces how the problem arose during the Cold War on both sides of the Iron Curtain, and gives examples of the problem from a variety of disciplines, including economics, physics, and biology. He explores problems that capture the full difficulty of the P-NP dilemma, from discovering the shortest route through all the rides at Disney World to finding large groups of friends on Facebook. But difficulty also has its advantages. Hard problems allow us to safely conduct electronic commerce and maintain privacy in our online lives. The Golden Ticketexplores what we truly can and cannot achieve computationally, describing the benefits and unexpected challenges of the P-NP problem.