Newtonian Gravitation Research Articles

Gravitational and Anti-Gravitational Applications

Because gravitation operates by a flow from the attracting object acting on the attracted object as shown in the prior papers Connecting Newton’s G With the Rest of Physics-Modern Newtonian Gravitation Resolving the Problem of “Big G’s” Value and The Mechanics of Gravitation-What It Is; How It Operates, it is now possible to partially deflect gravitation away from an object so that the gravitational attraction on the object is reduced. That effect makes it possible to extract energy from the gravitational field, which makes the generation of gravito-electric power technologically feasible. Such plants would be similar to hydro-electric plants and would have their advantages of not needing fuel and not polluting the environment. Physically, the action of deflecting away gravitational attraction, which of course is directed toward the gravitation source, produces an equal but opposite reaction on the mechanism that produces the deflection of the gravitational action [the deflector], a reaction directed away from the gravitation source. The result is the combination of reducing the gravitational attractive acceleration of the object toward the gravitation source plus the introducing of a reactive acceleration on the object in the direction away from the gravitation source. Such a deflector, engineered to enable controlled adjustment of the amount and the direction of its action, could provide for a spacecraft both launch levitation and deep space travel acceleration. It could provide both levitation and horizontal motion for a flying vehicle over a planet surface. This technology, which uses readily abundantly available materials and techniques, is ready now for research and engineering refinement.

Generalising the coupling between spacetime and matter

We explore the idea that the coupling between matter and spacetime is more complex than the one originally envisioned by Einstein. We propose that such coupling takes the form of a new fundamental tensor in the Einstein field equations. We then show that the introduction of this tensor can account for dark phenomenology in General Relativity, maintaining a weak field limit compatible with standard Newtonian gravitation. The same paradigm can be applied any other theory of gravitation. We show, as an example, that in the context of conformal gravity a generalised coupling is able to solve compatibility issues between the matter and the gravitational sector.

A paradox of Newtonian gravitation and Laplace’s solution

Newton’s theory of gravitation solvedmany problems of celestialmechanics but led to some major problems, one of which was that it gave rise to a serious paradox discussed in this article. The paradox has a number of manifestations one of which is presented here. It should be remembered that the root cause of all these paradoxes is fundamentally the same. Laplace attempted an ad hoc solution. However, it could not be mathematically demonstrated that his proposal solves the difficulty. In this article, it is shown that his suggestion removes the problem. A physical phenomenon that can justify Laplace’s suggestion is also mentioned briefly. This article also poses an interesting mathematical problem that can be attempted by interested readers. The computational solution is presented here.

Dark Matter, a Direct Detection

In a previous paper, we demonstrated that the linearized general relativity could explain dark matter (the rotation speed of galaxies, the rotation speed of dwarf satellite galaxies, the movement in a plane of dwarf satellite galaxies, the decreasing quantity of dark matter with the distance to the center of galaxies’ cluster, the expected quantity of dark matter inside galaxies and the expected experimental values of parameters Ωdm of dark matter measured in CMB). It leads, compared with Newtonian gravitation, to taking in account the second component (gravitational field) of the gravitation (imposed by general relativity) without changing the gravity field (also known as gravitomagnetism). In this explanation, dark matter would be a uniform gravitational field that embeds some very large areas of the universe generated by the clusters. In this article we are going to see that this specific gravitational field, despite its weakness, could be soon detectable, allowing testing this explanation of dark matter. It should generate a slight discrepancy in the expected measure of the Lense-Thirring effect of the Earth. In this theoretical frame, the Lense-Thirring effect of the “dark matter” would be a value between around 0.3 milliarcsecond/year and 0.6 milliarcsecond/year in the best case. In the LAGEOS or Gravity Probe B experiments, there was not enough precision (around 0.3% for the expected 6606 mas·y﹣1geodetic and around 19% for the expected 39 mas·y﹣1 frame-dragging precessions). In the GINGER experiment, there could be enough one; the expected accuracy would be around 1%. If this discrepancy was verified, it would be the first direct measure of the dark matter.

A Note on non-relativistic gravitation

Using the Jefimenko theory of gravitation [1] and the Le-Bellac, Levy-Leblond non relati-vistic approximations of Maxwellequations, we prove that in addition to newtonian gravi-tation, there exists a second non-relativistic gravitation.

On the meaning of Painlevé–Gullstrand synchronization

Following on from two recent papers, here we examine the relationship between Newtonian gravitation and general relativity in more depth. This allows us to define a scalar potential which is just the proper time of the vector potential when the latter is interpreted as the geodesic velocity field. The results are closely related to spacetimes that admit Painlev\'{e}--Gullstrand synchronization.

Are Newtonian Gravitation and Geometrized Newtonian Gravitation Theoretically Equivalent?

I argue that a criterion of theoretical equivalence due to Clark Glymour [Nous 11(3), 227-251 (1977)] does not capture an important sense in which two theories may be equivalent. I then motivate and state an alternative criterion that does capture the sense of equivalence I have in mind. The principal claim of the paper is that relative to this second criterion, the answer to the question posed in the title is yes, at least on one natural understanding of Newtonian gravitation.

Curved non-relativistic spacetimes, Newtonian gravitation and massive matter

There is significant recent work on coupling matter to Newton-Cartan spacetimes with the aim of investigating certain condensed matter phenomena. To this end, one needs to have a completely general spacetime consistent with local non-relativistic symmetries which supports massive matter fields. In particular, one cannot impose a priori restrictions on the geometric data if one wants to analyze matter response to a perturbed geometry. In this paper, we construct such a Bargmann spacetime in complete generality without any prior restrictions on the fields specifying the geometry. The resulting spacetime structure includes the familiar Newton-Cartan structure with an additional gauge field which couples to mass. We illustrate the matter coupling with a few examples. The general spacetime we construct also includes as a special case the covariant description of Newtonian gravity, which has been thoroughly investigated in previous works. We also show how our Bargmann spacetimes arise from a suitable non-relativistic limit of Lorentzian spacetimes. In a companion paper [M. Geracie et al., e-print arXiv:1503.02680], we use this Bargmann spacetime structure to investigate the details of matter couplings, including the Noether-Ward identities, and transport phenomena and thermodynamics of non-relativistic fluids.

Newtonian wormholes with spherical symmetry and tidal forces on test particles

A spherically symmetric wormhole in Newtonian gravitation in curved space, enhanced with a connection between the mass density and the Ricci scalar, is presented. The wormhole, consisting of two connected asymptotically flat regions, inhabits a spherically symmetric curved space. The gravitational potential, gravitational field and the pressure that supports the fluid that permeates the Newtonian wormhole are computed. Particle dynamics and tidal effects in this geometry are studied. The possibility of having Newtonian black holes in this theory is sketched.

The 2D surfaces that generate Newtonian and general relativistic orbits with small eccentricities

Embedding diagrams prove to be quite useful when learning general relativity as they offer a way of visualizing spacetime curvature through warped two dimensional (2D) surfaces. In this manuscript, we present a different 2D construct that also serves as a useful conceptual tool for gaining insight into gravitation: orbital dynamics—namely, the cylindrically symmetric surfaces that generate Newtonian and general relativistic orbits with small eccentricities. Although we first show that no such surface exists that can exactly reproduce the arbitrary bound orbits of Newtonian gravitation or of general relativity (or, more generally, of any spherically symmetric potential), surfaces do exist that closely approximate the resulting orbital motion for small eccentricities (exactly the regime that describes the motion of the solar system planets). These surfaces help to illustrate the similarities and differences between the two theories of gravitation (i.e., stationary elliptical orbits in Newtonian gravitation and precessing elliptical-like orbits in general relativity) and offer, in this age of 3D printing, an opportunity for students and instructors to experimentally explore the predictions made by each.

Using Gravitational Search Algorithm for in Advance Reservation of Resources in Solving the Scheduling Problem of Works in Workflow Workshop Environment

The scheduling problem of N independent works on M machines in the environment of permutation workflow workshop along with processing time and the desired delivery date are types of static problems, and except the machinery limitation as resources, no other limitation governs on it. Due to the importance of on time completion of work and minimizing delivery time of work, checking them is necessary in real word situations and will be properly effective on orders expedition and customer satisfaction. In this paper, one purpose of minimizing the sum of delays and on times (ΣE/T), is factor of recourses in advance reservation. The other main purpose is to present a new method called TIME_GSA using the Gravitational Search Algorithm (GSA) in order to solve the scheduling problem of works in workflow workshop environment, based on minimizing criteria of the sum of works delays and on times for resources in advance reservation. In this article, a novel optimization algorithm in the basis of gravitation law and mass interactions is presented to resolve the above problem. The suggested algorithm utilizes two of four basic factors connected to velocity and gravitational force in physics, based on random search concepts. The searcher agents are a group of masses which interact with each other based on the Newtonian gravitation and the laws of motion. The suggested procedure is compared with GA algorithm; the results approve the excellent performance of the suggested procedure to resolve the above problem.

Friedman׳s thesis

This essay examines Friedman׳s recent approach to the analysis of physical theories. Friedman argues against Quine that the identification of certain principles as ‘constitutive’ is essential to a satisfactory methodological analysis of physics. I explicate Friedman׳s characterization of a constitutive principle, and I evaluate his account of the constitutive principles that Newtonian and Einsteinian gravitation presuppose for their formulation. I argue that something close to Friedman׳s thesis is defensible.

Dark matter, dark energy and gravity

Within the framework of the Generation Model (GM) of particle physics, gravity is identified with the very weak, universal and attractive residual color interactions acting between the colorless particles of ordinary matter (electrons, neutrons and protons), which are composite structures. This gravitational interaction is mediated by massless vector bosons (hypergluons), which self-interact so that the interaction has two additional features not present in Newtonian gravitation: (i) asymptotic freedom and (ii) color confinement. These two additional properties of the gravitational interaction negate the need for the notions of both dark matter and dark energy.

A Constructive Model of Newtonian Gravitation

The paper explores whether Newtonian gravitation is mediated by force fields, and, if so, whether it can explain known gravitational phenomena. In conformity with the historical and conventional practice, the paper presents a physical model in which gravit...

Adjacency in hospital planning

Adjacencies stand at the beginning of a multitude of planning tasks. Especially in hospital planning they are essential for describing relationships between different organizational units - e.g. ‘close’, ‘distant’ or ‘neutral’. Mathematically, these terms map to relative weights between each pair of units in the range [-1, 1] which are put into a (symmetric) adjacency matrix. This matrix subsequently determines relative locations of individual spaces (preliminary space layout). The paper deals with the effective definition of this adjacency matrix in the context of early-stage architectural planning. In contrast to current planning practice, which looks at each adjacency relation in isolation, our approach uses a Newtonian gravitation model to propagate changes to a single relationship immediately to the whole space layout. As a result, we are able to supply architects with a design tool that accelerates the definition of adjacencies and lets them preview the preliminary space layout at the same time.

What Is a Singularity in Geometrized Newtonian Gravitation?

I discuss singular space-times in the context of the geometrized formulation of Newtonian gravitation. I argue first that geodesic incompleteness is a natural criterion for when a model of geometrized Newtonian gravitation is singular, and then I show that singularities in this sense arise naturally in classical physics by stating and proving a classical version of the Raychaudhuri-Komar singularity theorem.

Newtonian wormholes

A wormhole solution in Newtonian gravitation, enhanced through an equation relating the Ricci scalar to the mass density, is presented. The wormhole inhabits a spherically symmetric curved space, with one throat and two asymptotically flat regions. Particle dynamics in this geometry is studied, and the three distinct dynamical radii, namely, the geodesic, circumferential, and curvature radii, appear naturally in the study of circular motion. Generic motion is also analysed. A limiting case, although inconclusive, suggests the possibility of having a Newtonian black hole in a region of finite (nonzero) size.

Homothetic motions and Newtonian cosmology

We consider the homothetic motion group. We construct a homothetic covariant Newtonian gravitation theory which unifies inertial homothetic forces and gravitational fields. This is achieved through an equivalence principle based on a local homothetic frame of motion. As a consequence, we can obtain a coherent Newtonian cosmology which admits a cosmological principle and leads to the Friedman equations for a dust universe. Finally we prove that this gravity theory can be obtained as the non-relativistic limit of a class of metrics in General Relativity. The Friedmann-Lema\^\i tre-Robertson-Walker (FLRW) metric and its limit are also studied.

The Geometry of Conventionality

There is a venerable position in the philosophy of space and time that holds that the geometry of spacetime is conventional, provided one is willing to postulate a “universal force field.” Here we ask a more focused question, inspired by this literature: in the context of our best classical theories of space and time, if one understands “force” in the standard way, can one accommodate different geometries by postulating a new force field? We argue that the answer depends on one’s theory. In Newtonian gravitation the answer is yes; in relativity theory, it is no.

Galaxy rotation curves from a fourth order gravity

While the standard and most popular explanation for the flatness of galaxy rotation curves is dark matter, one cannot at this stage rule out an explanation based on a modified law of gravitation, which agrees with Newtonian gravitation on the scale of the Solar system, but differs from it on larger length scales. Examples include Modfied Newtonian Dynamics (MOND) and Scalar-Tensor-Vector Gravity (STVG). Here, we have reported on a fourth order modification of the Poisson equation, which yields the same Yukawa type modification of Newtonian gravity as STVG, and which can explain flat galaxy rotation curves for a large sample of galaxies, once specific values for two parameters have been chosen. We have speculated on two possible origins for this modified Poisson equation: First, a possible fourth order modification of general relativity, and second, quadrupole gravitational polarization induced on a galaxy because of the pull of neighbouring galaxies.