Search

The explanation of Einstein’s special theory of relativity in his original 1905 paper is examined. His analysis is confusing, as terms x, y, z, t, etc., have different meanings at various points, and he presents equations based on different and inconsistent assumptions. Adding subscripts clarifies these issues but exposes errors in his reasoning. To calculate his transformation equations, he selects a combination of equations which gives results matching the Lorentz transformation but he ignores other possible valid solutions. Also his calculations contain serious errors. Therefore, he fails to prove that his theory leads to the Lorentz equations as a unique solution. Einstein’s analysis includes “moving” clocks which show “stationary” time t, so the idea that a moving clock should run slower than a stationary clock is incompatible with his theory. Also, his calculation of time dilation contains serious errors. As a result, he fails to provide a theoretical justification for his famous “clocks paradox.” [ABSTRACT FROM AUTHOR]

Copyright of Physics Essays is the property of Physics Essays Publication and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, reference standards and reference multipliers are suggested as a means to compare the citation impact of earlier research publications in physics (from the period of “Little Science” in the early 20th century) with that of contemporary papers (from the period of “Big Science,” beginning around 1960). For the development of time-specific reference standards, the authors determined (a) the mean citation rates of papers in selected physics journals as well as (b) the mean citation rates of all papers in physics published in 1900 (Little Science) and in 2000 (Big Science); this was accomplished by relying on the processes of field-specific standardization in bibliometry. For the sake of developing reference multipliers with which the citation impact of earlier papers can be adjusted to the citation impact of contemporary papers, they combined the reference standards calculated for 1900 and 2000 into their ratio. The use of reference multipliers is demonstrated by means of two examples involving the time adjusted h index values for Max Planck and Albert Einstein. [ABSTRACT FROM AUTHOR]

The Einstein Papers Project (EPP) was honored to receive the British Society of Indexers' Wheatley Medal in 2009 for its cumulative index to the first ten volumes of The collected papers of Albert Einstein (CPAE). The experience introduced us to SI and its standards of excellence in the field. This, in turn, encouraged us to reflect on our methods of indexing and to consider ways of improving them. This article provides a measure of thanks for the recognition awarded by SI and for the lessons learned in the craft of indexing. We do this in the form of a brief narrative about the origins and aims of the EPP, vignettes from two CPAE volumes of events surrounding Einstein's breakthrough to celebrity, details of our working methods in preparing the volumes and indexes, and a discussion of improvements we are considering for the indexes of future volumes. [ABSTRACT FROM AUTHOR]

It is well-known that Einstein's first paper E=mc2 on as published in the Annalen der Physik in 1905 is problematic in that it suffers from the error of circular reasoning. This means that it uses as one of its premises a statement which is equivalent to the conclusion of the paper, namely, that . E=mc2 This difficulty with the paper has been pointed out by many writers including Max Planck, Herbert Ives, Max Jammer and also biographers of Einstein including Gerald Holton and Arthur I. Miller. Unfortunately, the derivation is repeated today as being correct without any mention of the above criticisms of it. In view of this it seems to us worthwhile to have a clear and as simple as possible explanation of the logical difficulties associated with Einstein's 1905 derivation, and it is to this end that this paper is written. Herewith we present a very simple treatment of the problem which makes absolutely clear the logical difficulties in Einstein's first published work on E=mc2 [ABSTRACT FROM AUTHOR]

Reproducibility of results is a cornerstone of the scientific method. Scientific computing encounters two challenges when aiming for this goal. Firstly, reproducibility should not depend on details of the runtime environment, such as the compiler version or computing environment, so results are verifiable by third-parties. Secondly, different versions of software code executed in the same runtime environment should produce consistent numerical results for physical quantities. In this manuscript, we test the feasibility of reproducing scientific results obtained using the IllinoisGRMHD code that is part of an open-source community software for simulation in relativistic astrophysics, the Einstein Toolkit. We verify that numerical results of simulating a single isolated neutron star with IllinoisGRMHD can be reproduced, and compare them to results reported by the code authors in 2015. We use two different supercomputers: Expanse at SDSC, and Stampede2 at TACC. By compiling the source code archived along with the paper on both Expanse and Stampede2, we find that IllinoisGRMHD reproduces results published in its announcement paper up to errors comparable to round-off level changes in initial data parameters. We also verify that a current version of IllinoisGRMHD reproduces these results once we account for bug fixes which have occurred since the original publication. [ABSTRACT FROM AUTHOR]

Copyright of Physics Essays is the property of Physics Essays Publication and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article reviews the web site Collected Papers of Albert Einstein, available at einsteinpapers.press.princeton.edu/, from Princeton University Press, the California Institute of Technology, and the Hebrew University of Jerusalem.

In his groundbreaking 1905 paper on special relativity, Einstein distinguished between local and global time in inertial systems, introducing his famous definition of distant simultaneity to give physical content to the notion of global time. Over the following decade, Einstein attempted to generalize this analysis of relativistic time to include accelerated frames of reference, which, according to the principle of equivalence, should also account for time in the presence of gravity. Characteristically, Einstein's methodology during this period focused on simple, intuitively accessible physical situations, exhibiting a high degree of symmetry. However, in the final general theory of relativity, the a priori existence of such global symmetries cannot be assumed. Despite this, Einstein repeated some of his early reasoning patterns even in his 1916 review paper on general relativity and in later writings. Modern commentators have criticized these arguments as confused, invalid, and inconsistent. Here, we defend Einstein in the specific context of his use of global time and his derivations of the gravitational redshift formula. We argue that a detailed examination of Einstein's early work clarifies his later reasoning and demonstrates its consistency and validity. [ABSTRACT FROM AUTHOR]

Although high school physics students solve problems using the expression E = mc², the origin of this expression and its deep conceptual meaning are hardly ever discussed due to students' limited prior knowledge. In 1946, a year after the atomic bombs were first dropped, Albert Einstein published a popular scientific paper explaining the equivalence between mass and energy to the general public and the implications of this principle for our daily lives. This paper describes the utilization of Einstein's paper in a high-school physics lesson on the equivalence of mass and energy, and discusses the instructional affordances of discussing exemplary popular scientific texts in a physics lesson. [ABSTRACT FROM AUTHOR]

Copyright of Studia Historiae Scientiarum is the property of Jagiellonian University Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The derivation of mass-energy equivalence, called Einstein's Relation, was derived through different ways by Einstein and appeared in his article published in 1905. In this research paper, the authors present Einstein's method in new ways, where a general method valid to all of the relativistic and non-relativistic phenomena is proposed by applying the physical law and the classical principle of relativity. [ABSTRACT FROM AUTHOR]

Abstract: Examination of Einstein''s 1905 landmark paper On the electrodynamics of moving bodies reveals that his obtaining of the Lorentz transformation equations contains shortcomings apparently previously unnoticed or unremarked. Modifications of his analysis as well as extension of the procedures he has chosen allows his approach to be made into a complete proof, while still remaining within the framework of his method. [Copyright &y& Elsevier]

This article reviews Albert Einstein's first published paper, submitted for publication in 1900. At that time, Einstein was 21 and a recent college graduate. His paper uses modeling and least squares to analyze data in support of a scientific proposition. Einstein is shown to be well trained, for his day, in using statistics as a tool in his scientific research. This paper also shows his ability to make trivial arithmetic mistakes and some clumsiness in data recording. A major aim of this article is to help provide a better appreciation of Einstein as an active user of statistical arguments in this and other of his important publications. [ABSTRACT FROM AUTHOR]

Copyright of Physics Essays is the property of Physics Essays Publication and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In a 1936 manuscript submitted to the Physical Review, Albert Einstein and Nathan Rosen famously claimed that gravitational waves do not exist. It has generally been assumed that there was a conceptual error underlying this fallacious claim. It will be shown, through a detailed study of the extant referee report, that this claim was probably only the result of a calculational error, the accidental use of a pathological coordinate transformation. [ABSTRACT FROM AUTHOR]

During the 99 years of its history, the Journal of Comparative Physiology A has published many of the most influential papers in comparative physiology and related disciplines. To celebrate this achievement of the journal's authors, annual Editors' Choice Awards and Readers' Choice Awards are presented. The winners of the 2023 Editors' Choice Awards are 'Contact chemoreception in multi‑modal sensing of prey by Octopus' by Buresch et al. (J Comp Physiol A 208:435–442, 2022) in the Original Paper category; and 'Magnetic maps in animal navigation' by Lohmann et al. (J Comp Physiol A 208:41–67, 2022) in the Review/Review-History Article category. The winners of the 2023 Readers' Choice Awards are 'Coping with the cold and fighting the heat: thermal homeostasis of a superorganism, the honeybee colony' by Stabentheiner et al. (J Comp Physiol A 207:337–351; 2021) in the Original Paper category; and 'Einstein, von Frisch and the honeybee: a historical letter comes to light' by Dyer et al. (J Comp Physiol A 207:449–456, 2021) in the Review/Review-History category. [ABSTRACT FROM AUTHOR]

We considered in Example 3.1 of the paper [1] an S-structure on R2 n+ s. We concluded that when s > 1 this manifold cannot be of constant φ-sectional curvature. Unfortunately this result is wrong. In fact, essentially due to a sign mistake in defining the φ-structure and a consequent transposition of the elements of the φ-basis (3.2), some of the Christoffel’s symbols were incorrect. In the present rectification, using a more slendler tecnique, we prove that our manifold is of constant φ-sectional curvature −3 s and then it is η-Einstein. [ABSTRACT FROM AUTHOR]

Reports that Princeton University Press will publish the first volume of the 'Collected Papers and Correspondence of Albert Einstein' in 1984. Funding for the publication; Scope of the book; Obstacles in translating Einstein's German writings.

Arthur Stanley Eddington (1882–1944) was one of the leading astrophysicists of the first half of the 20th century. He is remembered today chiefly for his research into stellar structure and general relativity, both of which he began to explore in the mid-1910s. He was also a key participant in the famous eclipse expeditions of 1919 that tested Einstein's theory of gravity. Rather than consider these topics, in this paper I will instead examine Eddington's early astronomical career, that is, from 1906 to about 1915. In this period, he became a well-trained practical astronomer. Eddington also established himself as a brilliant theoretical astronomer, and in so doing helped to create the role of theoretical astrophysicist through his research into star streaming. He was also, unusually for astronomers of this period, an enthusiastic advocate of the use of "working hypotheses" as crucial tools in astronomical practice. The study of Eddington's early career therefore has much to tell us about the nature of astronomy in the years around 1910 and about Eddington. The paper underlines, for example, the continuing relevance of the "Greenwich-Cambridge Axis" for the power structure of British astronomy, and the importance of the so-called Sidereal Problem for astronomers at this time even though today it is largely forgotten. [ABSTRACT FROM AUTHOR]

Gravitational waves are being shown to derive directly from Newtonian dynamics for a continuous mass distribution, e.g. compressible fluids or equivalent. It is shown that the equations governing a continuous mass distribution, i.e. the inviscid Navier–Stokes equations for a general variable gravitational field g(t,x) , are equivalent to a form identical to the Maxwell equations from electromagnetism, subject to a specified condition. The consequence of this equivalence is the creation of gravity waves that propagate at a finite speed. The latter implies that Newtonian gravitation as presented in this paper is not 'spooky action at a distance' but rather is similar to electromagnetic waves propagating at finite speed, despite the apparent form appearing in the integrated field formula. In addition, this proves that, in analogy to the Maxwell equations, the Newtonian gravitation equations are Lorentz invariant for waves propagating at the speed of light. Since gravitational waves were so far derived only from Einstein's general relativity theory, it becomes appealing to check if there is a connection between the Newtonian waves presented in this paper and the general relativity type of waves at least in a certain limit of overlapping validity, i.e. as a flat-space approximation. The latter is left for follow-up research. [ABSTRACT FROM AUTHOR]

Presents information on the importance of gravitational lensing, as an astrophysical consequence of the general theory of relativity. Reason for Albert Einstein's disregard of gravitational lensing as a speculative idea; Basic features of the lensing effect; Background information on gravitational lensing.

We review and extend the results of our 2021 paper concerning the problem of tidal evolution of a binary system with a rotating primary component with rotation axis arbitrarily inclined with respect to the orbital plane. Only the contribution of quasi-stationary tides is discussed. Unlike previous studies in this field we present evolution equations derived "from first principles." The governing equations contain two groups of terms. The first group of terms determines the evolution of orbital parameters and inclination angles on a long time scale determined by the rate of energy dissipation often described as a "viscous" time scale though radiative damping may also be included. It can be shown that these terms are formally equivalent to corresponding expressions obtained by other authors after a map between the variables adopted is established. The second group of terms is due to stellar rotation. These terms are present even when dissipation in the star is neglected. They may lead to conservative evolution of the angles specifying the orientation of the stellar rotation axis and the orbital eccentricity vector on a relatively short time scale. The corresponding evolution is also linked to the rate of apsidal precession of the binary orbit. Unlike in our 2021 paper we consider all potentially important sources of apsidal precession in an isolated binary, namely precession arising from the tidal distortion and rotation of the primary as well as Einstein precession. We solve these equations numerically for a small sample of input parameters, leaving a complete analysis to an accompanying paper. Periodic changes to both the inclination of the rotational axis and its precession rate are found. In particular, for a particular binary parameters periodic flips between prograde and retrograde rotation are possible. Also, when the inclination angle is allowed to vary, libration of the apsidal angle becomes possible. Furthermore, when the spin angular momentum is larger than the orbital angular momentum there is a possibility of a significant periodic eccentricity changes similar those coming about from the well-known Kozai–Lidov effect. These phenomena could, in principle, be observed in systems with relatively large inclinations and eccentricities such as, e.g., those containing a compact object. In such systems both large inclinations and eccentricities could be generated as a result of a kick applied to the compact object during a supernova explosion. The paper is based on a talk presented at the astrophysical memorial seminar "Novelties in Understanding the Evolution of Binary Stars," dedicated to the 90th anniversary of Professor M.A. Svechnikov. [ABSTRACT FROM AUTHOR]

Copyright of Physics Essays is the property of Physics Essays Publication and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of the present paper is to clarify, as far as it is possible, the overall picture of experimental results in the field of non-conventional phenomena in nuclear matter published in the scientific literature, accumulated in the past few decades and still missing a widely accepted interpretation. Completeness of the collection of the experiments is not among the aims of the effort; the focus is on adopting a more comprehensive and integral approach through the analysis of the different experimental layouts and different results, searching for common features and analogous factual outcomes in order to obtain a consistent reading of many experimental evidences that appear, so far, to lack a classification in a logic catalogue, which might be compared to a building rather than a collection of single stones. Particular attention is put on the issue of reproducibility of experiments and on the reasons why such a limitation is a frequent characteristic of many experimental activities reported in published papers. This approach is innovative as compared with those already available in the scientific literature. In a synoptical table, a comprehensive classification is given of the twenty experiments examined in terms of types of evidences that are ascertained by the experimenters in their published papers but are "unexpected" according to well-established physical theories. Examples of such unexpected evidences (named also non-conventional or weird) evidences are: excess heat generation, isotope production, reduction of radioactivity levels, and production of neutrons or alpha particles. These evidences are classified taking into account both the material where the evidence takes place (solutions, metals, rocks and artificial materials) and the stimulation techniques (supply of electric voltage, irradiation by photons, mechanical pressure) used to generate the evidences (which do not appear in the absence of such stimuli at an appropriate intensity). Also, in our paper, "identity cards" are provided for each experiment examined, including details that emerged during the experiment and were reported in each respective paper, that sometimes are not given adequate consideration either by the author of the experiment or in other review papers. The analysis of the details provides suggestions (also referred to as clues in this papers) used to formulate the content of the second part of each identity card, where inferences deduced from facts are outlined in view of presenting tentative interpretation at the microscopic level. This is done by concentrating attention on the clues repeated in different experiments in order to yield possible explanations of the "unexpected" evidences. The main outcome of such analysis is that, in all examined cases, a common "operation" can be identified: the stimulation techniques mentioned above can be interpreted as a sort of compression producing a ramp of energy densification (with reference to volumes in space or time coordinates). Here we use the term "compression" to indicate an operation activated by the experimenter; as such, it is objective. We consider energy densification an inference of possible consequences of the operation on the status of the system. Five types of densifications were identified. This reading in terms of energy densification is in accordance with the predictions of the Deformed Space Time theory, reported in the scientific literature, in the context of a generalization of the Einstein relativity theory, according to which the existence of energy thresholds is found to separate, for each interaction, the flat metric part from the deformed metric part and the appearance of new microscopic effects as a consequence of trespassing such thresholds. The phenomena occurring in the deformed part of the interaction metric are governed by the energy density in the space-time (volume and time interval). This energy density is computed from the threshold energies and is peculiar to the phenomenology under consideration. As a conclusion, it is suggested that the revealed qualified information, homogenized and elaborated on, might help in repeating, with proper adjustments and adequate additional instrumentation, some key experiments, in order to ensure systematic reproducibility, which is a prerequisite for interpretations and explanations to be sound and credible, as well in deriving from such an effort, indications for new experiments. It is uncomfortable that, after thirty years, there are still pending questions to which the most acknowledged physical theories are not capable of giving an answer. Even a definitive demonstration that all these experiments have decisive faults would be preferable than leaving the issue unaddressed. Major research agencies, for instance in the USA and in Europe, are moving in this direction. [ABSTRACT FROM AUTHOR]

At first glance, thermodynamic properties of gravity with asymptotically AdS conditions and those with box boundary conditions, where the spatial section of the boundary is a sphere of finite radius, appear similar. Both exhibit a similar phase structure and Hawking-Page phase transition. However, when we introduce a U(1) gauge field to the system, discrepancies in thermodynamic properties between the two cases has been reported in [7] (JHEP 11 (2016) 041). In this paper, by accepting the assumption that all Euclidean saddles contribute to the partition function, I found that these discrepancies are resolved due to the contribution from the "bag of gold (BG)," which is the class of Euclidean geometries whose area of bolt is bigger than that of the boundary. As a result, the Hawking-Page phase structure is restored, with the unexpected properties that the upper bound of thermodynamic entropy is always larger than the boundary area divided by 4G when the chemical potential is non-zero, and that such high entropy states are realized at sufficiently high temperature. [ABSTRACT FROM AUTHOR]

This paper is the fourth in a series dedicated to the mathematically rigorous asymptotic analysis of gravitational radiation under astrophysically realistic set-ups. It provides an overview of the physical ideas involved in setting up the mathematical problem, the mathematical challenges that need to be overcome once the problem is posed, as well as the main new results we will obtain in upcoming work. From the physical perspective, this includes a discussion of how post-Newtonian theory provides a prediction on the gravitational radiation emitted by N infalling masses from the infinite past in the intermediate zone, i.e. up to some finite advanced time. From the mathematical perspective, we then take this prediction, together with the condition that there be no incoming radiation from I− , as a starting point to set up a scattering problem for the linearized Einstein vacuum equations around Schwarzschild and near spacelike infinity, and we outline how to solve this scattering problem and obtain the asymptotic properties of the scattering solution near i0 and I+. The full mathematical details will be presented in the sequel to this paper. This article is part of a discussion meeting issue 'At the interface of asymptotics, conformal methods and analysis in general relativity'. [ABSTRACT FROM AUTHOR]

Recently proposed duality relates the critical level limit of WZW models to a classical three-dimensional Einstein gravity on a sphere. In this paper, we propose a dimensional reduced version of this duality. The gravity side is reduced to a Jackiw-Teitelboim (JT) gravity on S2 with a non-standard boundary term, or a BF theory with SU(2) gauge symmetry. At least in low temperature limit, these two-dimensional gravity theories completely capture the original three-dimensional gravity effect. The CFT side is reduced to a certain complex Liouville quantum mechanics (LQM) with SU(2) gauge symmetry. Our proposal gives an interesting example of a holography without boundary. We also discuss a higher-spin generalization with SU(N) gauge symmetry. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the concepts of Riemannian warped-twisted product submersions and examine their fundamental properties, including total geodesicity, total umbilicity and minimality. Additionally, we investigate the Ricci tensor of Riemannian warped-twisted product submersions, specifically about the horizontal and vertical distributions. Finally, we obtain Einstein condition for base manifold if the horizontal and vertical distributions of the ambient manifold is Einstein. [ABSTRACT FROM AUTHOR]

In previous works, we have proven that there are local tetrads in four-dimensional curved Lorentzian spacetimes that can be written in terms of two kinds of local structures, the skeletons and the gauge vectors. These tetrads diagonalize locally and covariantly the stress–energy tensors for systems of differential equations of the Einstein–Maxwell kind in the Abelian electromagnetic case, or of the Einstein–Maxwell–Yang-Mills kind when non-Abelian Yang–Mills fields are included, along with suitable Yang–Mills stress–energy tensors. Under local Lorentz transformations, these new tetrads conserve their skeleton-gauge vector structure. In this short paper, we will prove that given any general unit orthogonal tetrad in spacetime, we will be able to construct a new tetrad in the skeleton-gauge vector form. We will prove a theorem stating that the original orthonormal tetrad can be constructed or reexpressed with this same local tetrad skeleton-gauge vector structures. The theorems proved in this paper will enable the demonstration of new results in group isomorphism theorems in the future. [ABSTRACT FROM AUTHOR]

There are only limited theoretical results published on the transition properties of the X1Σ+, A1Π, B1Σ+, C1Δ, D1Σ−, E1Δ, a3Π, b3Σ+, and c3Δ states of BeS, and even some of the states have no theoretical and experimental reports on the relevant aspects of these transitions. Therefore, we derived these transition properties in this study. The potential energy curves of X1Σ+, A1Π, B1Σ+, C1Δ, D1Σ−, E1Δ, a3Π, b3Σ+, c3Δ, d3Σ−, and e3Σ− states of the BeS molecule with their Ω states and the transition dipole moments between them were calculated by the complete active space self-consistent field method, followed by the internally contracted multireference configuration interaction method. For the accurate computation of the transition properties, scalar relativistic corrections and core–valence correlation were considered. The radiative lifetimes were approximately 10−6 s for the A1Π and b3Σ+ states, 10−7 s for the E1Δ state, 10−7–10−8 s for the C1Δ and D1Σ− states, and 10−8 s for the B1Σ+, c3Δ, and e3Σ− states. The transition properties of the seven Ω states generated by the X1Σ+, A1Π, B1Σ+, and a3Π electronic states, including several electric dipole-forbidden transitions were researched. In particular, the B1Σ+0+–X1Σ+0+, B1Σ+0+–A1Π1, and A1Π1–X1Σ+0+ systems have strong transitions. In this paper, the radiative lifetimes of A1Π1, B1Σ+0+, a3Π0−, a3Π0+, and a3Π1 electronic states were also computed. For the A1Π1, B1Σ+0+, and a3Π1 states, the distribution of the radiation lifetime with the rotational angular momentum quantum number J at 0 ≤ υ ≤ 15 and J ≤ 70 was evaluated. It is expected that the outcome of the calculations in this paper can contribute some meaningful guidelines for conducting further theoretical and experimental investigations. [ABSTRACT FROM AUTHOR]

In this paper, we make a detailed side-by-side comparison between Jordan and Einstein frames in the context of cosmic magnetogenesis. We have computed the evolution of the vector potential in each frame along with some observables such as the spectral index and the magnetic field amplitude. We found that contrary to the Einstein frame, the electric and magnetic energy densities in the Jordan Frame do not depend on any parameter associated with the scalar field. Furthermore, in the Einstein frame, and assuming scale invariance for the magnetic field, most of the total energy density contribution comes from the electric and magnetic densities. Finally, we show the ratio between magnetic field signals in both frames printed in the CMB. [ABSTRACT FROM AUTHOR]

The aim of this paper is to prove some results about almost Yamabe soliton and almost Ricci-Bourguignon soliton with special soliton vector field. In fact, we prove that every compact non-trivial almost Ricci-Bourguignon soliton with constant scalar curvature is isometric to a Euclidean sphere. Then we show that every compact almost Ricci-Bourguignon soliton whose soliton vector field is divergence-free is Einstein and its soliton vector field is Killing. Finally, we prove that a complete almost Ricci-Bourguignon soliton (M, g, V, λ, ρ) has V as the contact vector field of a contact manifold M with metric g and its Reeb vector field is geodesic, then it becomes a Ricci-Bourguignon soliton and g has constant scalar curvature. In particular, if V is strict, then g is a compact Sasakian Einstein. [ABSTRACT FROM AUTHOR]

A topological interlocking assembly (TIA) is an assembly of blocks together with a non-empty subset of blocks called the frame such that every non-empty set of blocks is kinematically constrained and can therefore not be removed from the assembly without causing intersections between blocks of the assembly. TIA provides a wide range of real-world applications, from modular construction in architectural design to potential solutions for sound insulation. Various methods to construct TIA have been proposed in the literature. In this paper, the approach of constructing TIA by applying the Escher trick to tilings of orientable surfaces is discussed. First, the strengths of this approach are highlighted for planar tilings, and the Escher trick is then exploited to construct a planar TIA that is based on the truncated square tiling, which is a semi-regular tiling of the Euclidean plane. Next, the Escher-Like approach is modified to construct TIAs that are based on arbitrary orientable surfaces. Finally, the capabilities of this modified construction method are demonstrated by constructing TIAs that are based on the unit sphere, the truncated icosahedron, and the deltoidal hexecontahedron. [ABSTRACT FROM AUTHOR]

In this paper, we aim to characterize the sequential warped product κ -almost gradient conformal Ricci–Bourguignon soliton. We derive applications of some vector fields like conformal vector field, torse-forming vector field, torqued vector field on κ -almost conformal Ricci–Bourguignon soliton. The inheritance properties of the Einstein-like sequential warped product κ -almost gradient conformal Ricci–Bourguignon solitons of class types ℙ , , are investigated in this paper. Later we show that if M ̄ = (M 1 × f I M 2 ) × f ̄ I M 3 is a sequential warped product of a complete connected (n − 2) -dimensional Riemannian manifold M 1 and one-dimensional Riemannian manifolds I M 2 and I M 3 admitting κ -almost conformal Ricci–Bourguignon soliton, then (M 1 , g 1) becomes a (n − 2) -dimensional sphere of radius ρ = n − 2 r 1 + (μ − 1 2 (p + 2 n) + ρ R) (4 − n) . We have discovered that for a κ -almost gradient conformal Ricci–Bourguignon soliton sequential warped product, the warping functions are constants under certain conditions. [ABSTRACT FROM AUTHOR]

This research paper explores the properties of quasi-Einstein manifolds with a unit concircular generator vector field within doubly warped product structures. The paper begins by investigating the characteristics of quasi-Einstein manifolds that possess a unit concircular generator vector field. Subsequently, it analyzes the behavior of the Hessian, Riemann, and Ricci vector fields in the context of a doubly warped product. Moreover, the impact of the quasi-Einstein condition on both the doubly warped product and its factor manifolds is studied. Finally, conditions are derived to determine whether a doubly warped product satisfying the quasi-Einstein condition can be classified as a warped or a direct product. By presenting these findings, this study contributes to the comprehension of quasi-Einstein manifolds and their interactions within doubly warped product structures. [ABSTRACT FROM AUTHOR]

In this study, we characterize LP-Kenmotsu manifolds admitting *-Ricci-Yamabe solitons (*-RYSs) and gradient *-Ricci-Yamabe solitons (gradient *-RYSs). It is shown that an LP-Kenmotsu manifold of dimension n admitting a *-Ricci-Yamabe soliton obeys Poisson's equation. We also determine the necessary and sufficient conditions under which the Laplace equation is satisfied by LP-Kenmotsu manifolds. Finally, by using a non-trivial example of an LP-Kenmotsu manifold, we verify some results of our paper. [ABSTRACT FROM AUTHOR]

The spin-torsion theory is a gauge theory approach to gravity that expands upon Einstein's general relativity (GR) by incorporating the spin of microparticles. In this study, we further develop the spin-torsion theory to examine spherically symmetric and static gravitational systems that involve free-falling macroscopic particles. We posit that the quantum spin of macroscopic matter becomes noteworthy at cosmic scales. We further assume that the Dirac spinor and Dirac equation adequately capture all essential physical characteristics of the particles and their associated processes. A crucial aspect of our approach involves substituting the constant mass in the Dirac equation with a scale function, allowing us to establish a connection between quantum effects and the scale of gravitational systems. This mechanism ensures that the quantum effect of macroscopic matter is scale-dependent and diminishes locally, a phenomenon not observed in microparticles. For any given matter density distribution, our theory predicts an additional quantum term, the quantum potential energy (QPE), within the mass expression. The QPE induces time dilation and distance contraction, and thus mimics a gravitational well. When applied to cosmology, our theory yields a static cosmological model. The QPE serves as a counterpart to the cosmological constant introduced by Einstein to balance gravity in his static cosmological model. The QPE also offers a plausible explanation for the origin of Hubble redshift (traditionally attributed to the universe's expansion). The predicted luminosity distance–redshift relation aligns remarkably well with SNe Ia data from the cosmological sample of SNe Ia. In the context of galaxies, the QPE functions as the equivalent of dark matter. The predicted circular velocities align well with rotation curve data from the SPARC (Spitzer Photometry and Accurate Rotation Curves database) sample. Importantly, our conclusions in this paper are reached through a conventional approach, with the sole assumption of the quantum effects of macroscopic matter at large scales, without the need for additional modifications or assumptions. [ABSTRACT FROM AUTHOR]

The Janis–Newman–Winicour spacetime corresponds to a static spherically symmetric solution of Einstein equations with the energy momentum tensor of a massless quintessence field. It is understood that the spacetime describes a naked singularity. The solution has two parameters, b and s. To our knowledge, the exact physical meaning of the two parameters is still unclear. In this paper, starting from the Janis–Newman–Winicour naked singularity solution, we first obtain a wormhole solution by a complex transformation. Then, letting the parameter s approach infinity, we obtain the well-known exponential wormhole solution. After that, we embed both the Janis–Newman–Winicour naked singularity and its wormhole counterpart in the background of a de Sitter or anti-de Sitter universe with the energy momentum tensor of massive quintessence and massive phantom fields, respectively. To our surprise, the resulting quintessence potential is actually the dilaton potential found by one of us. It indicates that, by modulating the parameters in the charged dilaton black hole solutions, we can obtain the Janis–Newman–Winicour solution. Furthermore, a charged wormhole solution is obtained by performing a complex transformation on the charged dilaton black hole solutions in the background of a de Sitter or anti-de Sitter universe. We eventually find that s is actually related to the coupling constant of the dilaton field to the Maxwell field and b is related to a negative mass for the dilaton black holes. A negative black hole mass is physically forbidden. Therefore, we conclude that the Janis–Newman–Winicour naked singularity solution is not physically allowed. [ABSTRACT FROM AUTHOR]

Copyright of Physics Essays is the property of Physics Essays Publication and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Focuses on logbook records of the "Physical Review" citing the single possible encounter by professional physicist Albert Einstein with anonymous peer review regarding a paper he had written on gravitational waves. Factors that led Einstein to the conclusion that gravitational waves do not exist; Problems faced by Einstein in proving that gravitational waves do not exist; Description of how Einstein criticized the work of other physicists.

The article reviews the web site The Digital Einstein Papers: The Collected Papers of Albert Einstein, located at http://einsteinpapers.press.princeton.edu/ from the Princeton University Press.

In 1909, Lewis and Tolman, then physical chemists at the Massachusetts Institute of Technology, wrote a paper which built on an earlier paper by Lewis. This gave a more mechanics-based approach to the subject, in contrast to Einstein's original work which drew on electrodynamics. This work played a significant role in the early development of special relativity theory, then only four years old and still under heated discussion worldwide. This paper with Tolman, though a relatively minor part of Lewis's overall work, has historical and pedagogical value and gives a glimpse of his breadth, early growth and influence as a scientist. The present article outlines the arguments of their 1909 paper, and places it in context. [ABSTRACT FROM AUTHOR]

This paper investigates GPT-4's role as a research partner, particularly its ability to scrutinize complex theories like Einstein's Special Relativity Theory (SRT). GPT-4's advanced capabilities prove invaluable in complex research scenarios where human expertise might be limited. Despite initial biases, an inclination to uphold Einstein's theory, and certain mathematical limitations, GPT-4 validated an inconsistency within the SRT equations, leading to a questioning of the theory's overall validity. GPT-4 contributed significantly to honing the analytical approach and expanding constraints. This paper explores the strengths and challenges associated with the use of GPT-4 in scientific research, with a strong emphasis on the need for vigilance concerning potential biases and limitations in large language models. The paper further introduces a categorization framework for AI collaborations, and specific guidelines for optimal interaction with advanced models like GPT-4. Future research endeavors should focus on augmenting these models' precision, trustworthiness, and impartiality, particularly within complex or contentious research domains. [ABSTRACT FROM AUTHOR]

Copyright of Physics Essays is the property of Physics Essays Publication and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)