Attractive Gravitational Force Research Articles

New dynamical system for circular satellites relative motion

In this work, a new perturbed dynamical system to describe the satellites relative motion is derived considering that the gravitational attractive force is generated by the continued fraction potential. In this context, the parameter of continuation fraction creates an additional force which is the source of perturbation for motion. Aiming to find a simple and precise mathematical model to characterize this motion while maintaining high accuracy results, a new circular linear perturbed system is also derived under the effect of this parameter. Furthermore, the perturbed linear dynamical system of satellites relative motion is studied, along with finding the conditions of stable and periodic solutions. Finally, these solutions are calculated and their graphical simulation is introduced. We emphasize that the new proposed system could be applied in space rendezvous missions aiming at getting precise descriptions of satellites relative motion.

Calculation of the influence of the entropy of stars on the Earth's exosphere and the theory of entropic gravity

In the first part of this study, the entropic contribution of star objects, observable during the night between November 13 and 14, 2021, in the sky above Belgrade (Lat. 44o 49' 04'' N, Long. 20o 27' 25'' E, mean Elev. 117 m), Serbia, to the thermodynamic equilibrium of the Earth's exosphere, was determined. In the second part of the study, the force of gravitational attraction between the considered star objects and the Earth was calculated, by applying entropic gravity theory. The obtained results shed new light on the importance of star objects for sustaining the Earth's thermodynamic system.

Buffon, Species and the Forces of Reproduction.

Throughout the Histoire naturelle Buffon was ever aware of epistemological issues involving the reproduction of species, the only beings in nature. By the 1760s he had come to believe that empirical evidence, the source of all human knowledge, revealed that reproduction was a physical process, involving a common living (minute, active, and lively) matter and material forces, all of which he traced to the foundational force of gravitational attraction.

The role of Saturn’s magnetism in the equilibrium separation of particles of dense rings

For the first time we have demonstrated that, taking into account the interaction of Saturn's magnetic field with the diamagnetic ice particles of the rings, it is possible to explain the separation of particles. It is shown that there is an equilibrium distance between the particles when the force of gravitational attraction between them is compensated by the force of magnetic repulsion. An expression for calculating the equilibrium distance is obtained. It also becomes clear why the ring particles do not stick together.

Investigation of Companion Stars Around White Dwarfs

Astronomers have discovered numerous stars in galaxies, each with unique characteristics that mostly evolve into white dwarfs when reaching an evolutionary limit. A star with a low or medium mass less than about eight times the mass of the sun becomes a white dwarf after exhausting its nuclear fuels and begins to condense inwards by the force of gravitational attraction, leading to the final collapse. In this paper, the investigation analyzes three companion stars orbiting around three dwarfs by utilizing data provided by TESS (Tess Exoplanet Survey Satellite) Program G04137, providing more than 5200 candidate white dwarfs for a transiting planet. After testing 5200 known candidates of white dwarf provided by Tess Program G04137, the investigation decided to analyze three companion stars of TIC 403292348, TIC 1860468684, and TIC 356659664. In the first case study, the number of white dwarfs with the possibility of hosting planets is estimated from analyzing BLS data from listed white dwarfs in Sector 40, and the accuracy and limitations of this method are discussed qualitatively as well. In the second case of TIC-1860468684, the investigation analyzes a binary system with a young and bright White Dwarf and a low mass star, where the white Dwarf has tidally locked the star, and there may be nova formed in this system due to material transfer in the future. In the last case of TIC 356659664, the situation of a target is calculated, and possible cause of the target white dwarf’s flux curve is estimated. By analyzing three companion stars around white dwarfs, more data will be provided for astronomers for future scientific research.

THE EFFECT OF SOLAR RADIATION PRESSURE AND PLANET OBLATENESS ON THE LOCATION AND STABILITY OF LAGRANGIAN POINTS IN SOLAR SYSTEM PLANETS

The combined effect of the solar radiation pressure and the oblateness of the planets on the position and stability of the Lagrangian points within the restricted elliptic three-body problem was studied. We found that the solar radiation pressure and planet oblateness slightly changed the location of the Lagrangian points. New formulas for the location of the collinear points using the Lagrange inversion method were introduced. For large values of the force ratio B; the ratio between the solar radiation force and the gravitational attraction force due to the Sun; we found that the collinear point [Formula: see text] is stable.

Dark energy and dark matter in emergent gravity

Emergent gravity can be applied to a large $N$ matrix model by considering the vacuum of a noncommutative (NC) Coulomb branch that satisfies the Heisenberg algebra. Due to the fact that IR fluctuations in the NC Coulomb branch always pair with UV fluctuations, this UV/IR mixing is extendable to a macroscopic scale. These vacuum fluctuations in the NC Coulomb branch are described by a four-dimensional NC $U(1)$ gauge theory. The order parameter for the vacuum fluctuations is given by random four-vectors that have their own causal structure in the commutative limit unlike the conventional cosmological models based on a scalar field theory coupled to gravity. We show that their causal structure results in the different nature of gravitational interactions so that space-like fluctuations give rise to the repulsive gravitational force while time-like fluctuations generate the attractive gravitational force. Given the fact that the fluctuations are random in nature and we live in a (3+1)-dimensional spacetime, the ratio of the repulsive vs. attractive components ends up being 3:1 = 75:25, which is interestingly consistent with the dark components of the current universe. If we include ordinary matters acting as an attractive gravitational force, the emergent gravity could more accurately explain the dark side of our universe. This work is an expanded version of the conference proceedings (Yang in EPJ Web Conf 168:03006, 2018).

GRAVITATIONAL CASIMIR EFFECT IN INSPIRALLING NEUTRON STAR BINARY

Currently, the discussions and investigations for the vacuum energy are drawing great both theoretical and experimental attention. The vacuum states of variety of fields, subject to special boundary conditions, may contribute to non-trivial macroscopic vacuum energy, i.e., the Casimir effect, which become an interdisciplinary subject and plays an important role in a variety of fields of physics. We adopt Schwingers source theory and study the quantization of gravitation contributions to the Casimir effect, i.e., the gravitational Casimir effect, in inspiraling neutron star binaries with wide separation of 109 m. By considering gravitoelectromagnetism (GEM) arising from the spiral-in orbital motion and evaluating the gravitoelectromagnetic contributions to the vacuum energy of gravitons radiated during the orbital decay, we demonstrate that, when the radial separation of the system decay a distance L, the GEM results in a small Casimir correction to the gravitational vacuum energy, which contributes to an attractive gravitational Casimir force to the binary, in addition to the gravitational force. We also discuss the possible detections for such gravitational Casimir effect from both the future space-based gravitational wave observatories and cosmological observations.

GRAVITATIONAL CASIMIR EFFECT IN INSPIRALLING NEUTRON STAR BINARY

Currently, the discussions and investigations for the vacuum energy is drawing great both theoretical and experimental attention. The vacuum states of variety of fields, subject to special boundary conditions, may contribute to non-trivial macroscopic vacuum energy, i.e. the Casimir effect, which become an interdisciplinary subject and plays an important role in a variety of fields of physics. We adopt Schwinger's source theory and study the Casimir effect due to the quantization of gravitation, i.e. the gravitational Casimir effect (GCE), in inspiraling neutron star (NS) binaries with wide separation of $10^9 \rm m$. By considering gravitoelectromagnetism (GEM) arising from the spiral-in orbital motion and evaluating the contributions of GEM to the vacuum energy of gravitons radiated during the orbital decay, we demonstrate that, when the orbital separation of the binary decay a distance of $L$ in radial direction, the GEM results in a small Casimir correction to the gravitational vacuum energy, which contributes to an attractive gravitational Casimir force to the binary, in addition the gravitational force. The gravitational waves (GWs), emitted from wide inspiraling NS binaries, locate in the low-frequency band of $10^{-4}-1$ Hz. For a characteristic GW frequency of $10^{-3}$ Hz, the gravitational Casimir correction to the signals is estimated as of the order of $\sim10^{-24}$, which corresponds to a force of $10^{-20}$ N. By considering that the sensitivity of space-based gravitational wave observatory, LISA/eLISA and Taiji, can be reduced to $10^{-24}$, we would expect that LISA/eLISA and Taiji with sensitivity improvements give the powerful tool to detect GCE in the near future.

N-Body Simulation Inspired by Metaheuristics Optimization

The N-body problem in classical physics, is the calculation of force of gravitational attraction of heavenly bodies towards each other. Solving this problem for many heavenly bodies has always posed a challenge to physicists and mathematicians. Large number of bodies, huge masses, long distances and exponentially increasing number of equations of motion of the bodies have been the major hurdles in solving this problem for large and complex galaxies. Advent of high performance computational machines have mitigated the problem to much extent, but still for large number of bodies it consumes huge amount of resources and days for computation. Conventional algorithms have been able to reduce the computational complexity from to by splitting the space into a tree or mesh network, researchers are still looking for improvements. In this research work we propose a novel solution to N-body problem inspired by metaheuristics algorithms. The proposed algorithm is simulated for various time periods of selected heavenly bodies and analyzed for speed and accuracy. The results are compared with that of conventional algorithms. The outcomes show about 50% time saving with almost no loss in accuracy. The proposed approach being a metaheuristics optimization technique, attempts to find optimal solution to the problem, searching the entire space in a unique and efficient manner in a very limited amount of time.

Depression and anorexia detection in social media as a one-class classification problem

Taking advantage of the increasing amount of user-generated content in social media, some computational methods have already been proposed for detecting people suffering from depression and anorexia. Such complex tasks have been tackled as a binary classification problem using, in most cases, automatically generated training data. Despite its promising results, this approach has some important drawbacks, namely: it suffers from a severely skewed class distribution, the negative class is very diverse since it attempts to model all kinds of healthy users, and, above all, there is not a complete certainty about annotations, especially for the negative cases (i.e., healthy users). Motivated by these issues, in this paper, we propose to face the detection of these disorders following a one-class classification (OCC) approach. Particularly, we introduce two new instance-based OCC methods especially suited to manage the high diversity of content from social media documents. Taking up ideas from the gravitational attraction force, these methods evaluate the relation of documents by their strengths, considering their distances as well as their masses (relevance) with respect to the target task. Experiments were conducted on depression and anorexia benchmark datasets. The obtained results are encouraging; the overall performance was better than the results from other standard OCC methods, and competitive with regard to state-of-the-art results from binary classification approaches.

A Conceptual Model to Explain Dark Matter and Dark Energy

This paper considers a conceptual model that attempts to explain ‘Dark Matter’ and ‘Dark Energy’. The model is based on considering a gravitational field to be the result of a mass (a Higgs field) scattering pre-existing cosmic background space-time waves or ‘Uber-waves’. The term ‘Uber’ is used to denote an outstanding or supreme example of a particular kind of gravitational wave with cosmic-scale wavelengths that are far in excess of those associated with the gravitational waves generated by accelerating masses. Such waves are taken to be the very lowest frequency components associated with the spectrum of space-time waves generated by the ‘Big Bang’ and are supported by the expanding fabric of space-time produced at the point of the big bang, i.e. the lowest frequency components of a cosmological spectrum whose bandwidth is the a Planck frequency (～10∧43 Hz). Like electromagnetic waves, Uber waves are taken to propagate with an upper velocity consistent with the speed of light and interact with, and are scattered by, a Higgs field. This interaction produces the effect of a mass locally curving space-time, an idea that is contrary to the conventional model associated with General Relativity where mass is taken to curve space-time directly which otherwise remains ‘flat’. By assuming the pre-existence of background Uber waves, we consider the concave curvature of such waves to generate an apparent attractive gravitational force. This interaction produces the effect of a mass locally curving space-time, an idea that is contrary to the conventional model associated with General Relativity where mass is taken to curve space-time directly which otherwise remains ‘flat’. By assuming the pre-existence of background Uber waves, we consider the concave curvature of such waves to generate an apparent attractive gravitational force. This attractive force is taken to govern the formation of large scale structures of matter (galaxies and super-clusters of galaxies, for example) in the conventional sense but surrounded by a residual background gravitational field. It is this residual field that gives rise to the effect known as dark matter where more gravity (as an attractive only force) appears to be available than that which can be accounted for by the observed (luminous) mass, a luminosity that is generated primarily by nuclear fusion in stars. The convex curvature of Uber waves is considered to account for cosmic voids within which gravity is a repulsive force and where large scale structures of matter can therefore not be formed. This is considered to explain the super-large cosmic voids or super voids that are observed. These are regions of the universe where there is an absence of rich super clusters of matter. In these anti-gravity zones, only relatively small structures of matter can be formed by electrostatic forces alone which are then repelled from each other when their mass becomes significant enough for the force of anti-gravity to become significant. In such regions of an Uber wave, the matter generated from electrostatic forces builds up to produce a weak gravitational repulsive field due to the low mass density within a void. However, due to the immense size of these cosmic voids, they are taken to generate a net repulsive force which is considered to be the reason for the acceleration associated with the expansion of the universe; the effect of dark energy. This effect also accounts for the cosmic web structure in which luminescent matter appears to exist in relatively thin connective filaments. The purpose of this paper is to provide a conceptual model and not to investigate the ideas proposed in any significant mathematical detail. This is accomplished by building up the ideas on a case-by-case basis, coupled with a series of thought experiments but without resorting to specific physical scales or the physical parameters associated with these scales other than, by default, the speed of light and Newton’s gravitational constant.

Antigravity, an Answer to Nature’s Phenomena including the Expansion of the Universe

The gravitational attraction force being proportional to the mass has been experimentally shown for several hundred years now, but no gravitational repulsion has been identified within the accepted scientific reasoning. Here, we show that the gravitational repulsion force, similar to the gravitational attraction among particles has also been in existence in nature but, yet to be recognized. The results of experiments are shown in detail and are discussed in the recent series of-publications. It is also shown here that this gravitational repulsion force is proportional to the temperature which is an indicator of thermal energy of the particle, similar to the gravitational attraction that is proportional to the mass of the particle. The situations where heavy particles such as iodine, tungsten, and thorium in vacuum move against gravitational force have already been shown qualitatively. The increase in time-of-fall of water droplets (slowing down of fall) with rise in temperature is also quantitatively discussed. This article discusses two major phenomena observable in nature, clouds and the expansion of universe, which could be more preciously explained by the concept of antigravity.

Classical nonrelativistic effective field theory and the role of gravitational interactions

Coherent oscillation of axions or axion-like particles may give rise to long-lived clumps, called axion stars, because of the attractive gravitational force or its self-interaction. Such a kind of configuration has been extensively studied in the context of oscillons without the effect of gravity, and its stability can be understood by an approximate conservation of particle number in a non-relativistic effective field theory (EFT). We extend this analysis to the case with gravity to discuss the longevity of axion stars and clarify the EFT expansion scheme in terms of gradient energy and Newton's constant. Our EFT is useful to calculate the axion star configuration and its classical lifetime without any ad hoc assumption. In addition, we derive a simple stability condition against small perturbations. Finally, we discuss the consistency of other non-relativistic effective field theories proposed in the literature.

FROM THE CONTRACTING EARTH TO CONTINENTAL DRIFT: WEGENER'S INFLUENCE ON PORTUGUESE AND SPANISH SCIENCE TEXTBOOKS THROUGH THE TWENTIETH CENTURY

ABSTRACT Alfred Wegener's work on continental drift profoundly influenced the development of geology during the twentieth century. The main objective of this historical research is to explore how Wegener's hypothesis about the origin of continents and oceans influenced Portuguese and Spanish science textbooks published in the twentieth century. For this purpose, a qualitative method based on the Chevallard's concept of didactic transposition was used. The didactic transposition of the fundamentals of continental drift, including displacements forces and geographical, geophysical, geological, paleontological, biological, and paleoclimatic arguments used by Wegener to support this hypothesis, was studied in a comprehensive sample of twenty science textbooks published after the publication of Die Entstehung der Kontinente und Ozeane (Wegener 1915). The analysis of textbooks shows that the didactic transposition of continental drift was commonly present in Portuguese and Spanish textbooks beginning in the 1930s, although, with different degrees of development. Science textbooks since the 1950s presented the displacement forces of sial continental blocks proposed by Wegener, namely the centrifugal force of Earth's rotation and the attractive gravitational force that results from the interaction of the earth with the moon and sun. The geographical, geological, paleontological and biological arguments supporting continental drift were commonly addressed in many science textbooks, followed by the paleoclimatic arguments. The geophysical arguments were briefly addressed in only two textbooks. Many Portuguese and Spanish textbooks also presented critiques of Wegener's work, mainly focused on the lack of explanation for the origin and nature of forces that could move continents at the Earth's surface.

An Alternative Model of Rotation Curve that Explains Anomalous Orbital Velocity, Mass Discrepancy and Structure of Some Galaxies

A new model of galaxy rotation based on the cyclostrophic model of vortices found in nature is developed. The model is tested using the SPARC dataset of 175 galaxies and a smaller dataset comprising of 60 galaxies. Analysis of the datasets showed that galactic rotation can be adequately described using the observed surface brightness of galaxies and the newly developed cyclostrophic velocity model. The use of the luminosity and the inverse mass-to-light ratio in lieu of the surface brightness, also yield a very good fit of the observed and computed galaxy rotation velocity. Evidently, galactic rotation greatly depends on the cyclostrophic balance of the pressure gradient and the centrifugal forces and the seismic-induced radial expansion occurring in various stars. This is the most probable origin of the action of a single force law that has been overlooked in previous studies. Therefore, the need for a super-massive black hole at the center of galaxies or hidden dark matter can be eliminated. Attractive gravitational force can occur even without a massive black hole at the center of galaxies. There appears to be a pressure gradient force between the center and the outer parts of galaxies that sustains attraction. The cyclostrophic model appears to be the physical basis of the Tully-Fisher relation. Furthermore, the missing mass problem associated with galactic rotation can be attributed to the orbital expansion of celestial objects perturbed by seismic-induced forces. In addition, massive tremors or starquakes may create a domino effect in perturbing nearby stars along the axis of the seismic-induced force and this could result in the formation of elliptical galaxies as the orbits of seismic-perturbed neighboring stars become larger.

Kepler’s Ellipse Generated by the Trigonometrically Organized Gravitons

Johannes Kepler made his great breakthrough when he discovered the elliptical path of the planet Mars around the Sun located in one focus of that ellipse (on the 11th October in 1605 in a letter to Fabricius). The first generation of researchers in the 17th century intensively discussed about the possible mechanism needed for the generation of that elliptical orbit and about the function of the empty focus of that ellipse. First generations of researchers proposed an interplay between attractive and repulsive forces that might guide the planet on its elliptical orbit. Isaac Newton made a giant mathematical progress in his Principia and introduced the concept of the attractive gravitational force between the Sun and planets. However, Newton did not propose a possible mechanism behind this attractive force. Albert Einstein in 1915 left the concept of attractive and repulsive forces and introduced his Theory based on the elastic spacetime. In his concept gravity itself became fictitious force and the attraction is explained via the elastic spacetime. In our proposed model we try to re-open the discussion of Old Masters on the existence of attractive and repulsive forces. The guiding principle for our trigonometrical model is the generation of the ellipse discovered by one of the last ancient Greek mathematicians – Anthemius of Tralles – who generated the ellipse by the so-called gardener’s method (one string and two pins fixed to the foci of that ellipse). Frans van Schooten in 1657 invented a series of original simple mechanisms for generating ellipses, hyperbolas, and parabolas. Schooten’s antiparallelogram might simulate the interplay of attractive and repulsive forces creating the elliptical path. We propose a model with trigonometrically organized Solar and planet gravitons. In this model the Solar and planet gravitons are reflected and refracted in predetermined directions so that their joint momentum transferred on the planet atoms guides the planet on an elliptical path around the Sun. At this stage we cannot directly measure the gravitons but we can use the analogy with behavior of photons. We propose to observe paths of photons emitted from one focus of the ellipse towards the QUARTER-silvered elliptical mirror. 1/4 of photons will be reflected towards to the second empty focus and the ¾ of photons might be reflected and refracted into the trigonometrically expected directions. (Until now we have experimental data only for the FULLY–silvered elliptical mirrors). The observed behavior of photons with the quarter-silvered elliptic mirror might support this concept or to exclude this model as a wrong model. The quantitative values of attractive and repulsive forces could be found from the well-known geometrical properties of the ellipse. The characteristic lengths of distances will be inserted into the great formula of Isaac Newton - the inverse square law. (In order to explain some orbit anomalies, we can use Paul Gerber’s formula derived for the Pierre Fermat principle). We have found that the Kant’s ellipse rotating on the Keppler’s ellipse might express the co-operation of attractive and repulsive forces to guide the planet on its elliptic path. Finally, we have derived a new formula inspired by Bradwardine - Newton - Tan - Milgrom that might contribute to the MOND gravitational model. We have found that the Kepler ellipse is the very elegant curve that might still keep some hidden secrets waiting for our future research.

An axion-like scalar field environment effect on binary black hole merger

The environment, such as an accretion disk, could modify the signal of the gravitational wave from astrophysical black hole binaries. In this article, we model the matter field around intermediate-mass binary black holes by means of an axion-like scalar field and investigate their joint evolution. In detail, we consider equal mass binary black holes surrounded by a shell of axion-like scalar field both in spherically symmetric and non-spherically symmetric cases, and with different strengths of the scalar field. Our result shows that the environmental scalar field could essentially modify the dynamics. Firstly, in the spherically symmetric case, with increase of the scalar field strength, the number of circular orbits for the binary black hole is reduced. This means that the scalar field could significantly accelerate the merger process. Secondly, once the scalar field strength exceeds a certain critical value, the scalar field could collapse into a third black hole with its mass being larger than that of the binary. Consequently, the new black hole that collapses from the environmental scalar field could accrete the binary promptly and the binary collides head-on with each other. In this process, there is almost no quadrupole signal produced, and, consequently, the gravitational wave is greatly suppressed. Thirdly, when the scalar field strength is relatively smaller than the critical value, the black hole orbit could develop eccentricity through accretion of the scalar field. Fourthly, during the initial stage of the inspiral, the gravitational attractive force from the axion-like scalar field could induce a sudden turn in the binary orbits, hence resulting in a transient wiggle in the gravitational waveform. Finally, in the non-spherical case, the scalar field could gravitationally attract the binary moving toward the center of mass for the scalar field and slow down the merger process.

Dark Energy and Dark Matter from Emergent Gravity Picture

We suggest that dark energy and dark matter may be a cosmic uroboros of quantum gravity due to the coherent vacuum structure of spacetime. We apply the emergent gravity to a large N matrix model by considering the vacuum in the noncommutative (NC) Coulomb branch satisfying the Heisenberg algebra. We observe that UV fluctuations in the NC Coulomb branch are always paired with IR fluctuations and these UV/IR fluctuations can be extended to macroscopic scales. We show that space-like fluctuations give rise to the repulsive gravitational force while time-like fluctuations generate the attractive gravitational force. When considering the fact that the fluctuations are random in nature and we are living in the (3+1)-dimensional spacetime, the ratio of the repulsive and attractive components will end in ¾ : ¼= 75 : 25 and this ratio curiously coincides with the dark composition of our current Universe. If one includes ordinary matters which act as the attractive gravitational force, the emergent gravity may explain the dark sector of our Universe more precisely.

Baryonic Force for Accelerated Cosmic Expansion and Generalized U1b Gauge Symmetry in Particle-Cosmology

Based on baryon charge conservation and a generalized Yang-Mills symmetry for Abelian (and non-Abelian) groups, we discuss a new baryonic gauge field and its linear potential for two point-like baryon charges. The force between two point-like baryons is repulsive, extremely weak and independent of distance. However, for two extended baryonic systems, we have a dominant linear force α r. Thus, only in the later stage of the cosmic evolution, when two baryonic galaxies are separated by an extremely large distance, the new repulsive baryonic force can overcome the gravitational attractive force. Such a model provides a gauge-field-theoretic understanding of the late-time accelerated cosmic expansion. The baryonic force can be tested by measuring the accelerated Wu-Doppler frequency shifts of supernovae at different distances.