Results for 'curvature'

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  1. Is gravity, the curvature of spacetime or a quantum phenomenon.Alfonso Leon Guillen Gomez - 2014 - Journal of Advances in Physics 4 (1):194-203.
    Gravity is the curvature of spacetime, the structural property of static gravitational field, a geometric field, in curved coordinates, according the functions guv, that express geometric relations between material events. Course, general relativity is a relational theory, however, gravity, a thinking category, has symetric physical effects with matter. We use, analitic and critic method of reread the general relativity, since the perspective of the history of the science and the philosophy of the science. Our goal is driver the debate (...)
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  2. 2D geometry predicts perceived visual curvature in context-free viewing.Birgitta Dresp-Langley - 2015 - Computational Intelligence and Neuroscience 2015 (708759):1-9.
    Planar geometry was exploited for the computation of symmetric visual curves in the image plane, with consistent variations in local parameters such as sagitta, chordlength, and the curves’ height-to-width ratio, an indicator of the visual area covered by the curve, also called aspect ratio. Image representations of single curves (no local image context) were presented to human observers to measure their visual sensation of curvature magnitude elicited by a given curve. Nonlinear regression analysis was performed on both the individual (...)
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  3. An alternative to the Empirical Physics of Motion and Gravity in Explaining the Big Bang.Mohamed Magueramane - manuscript
    This paper is based on a proposition concerning the origins of the universe that would not hold without the following principles: (1) the big bang did not emerge from nothing, without a primordial cause; (2) the unempirical nature of Isaac Newton’s laws of inertia are unempirical lead to the conclusion that motion is inherent in the universe (3) gravity is a function of celestial objects falling and rotating around other objects as their natural motion gets obstructed; (4) Albert Einstein’s (...) of spacetime is not uniform. It follows that the massive cosmic explosion from the singularity event neither started spacetime, nor did it generate matter from nothing. The Spatial Discs Model (SDM) proposed here argues that all matter in our universe is finite, unstationary, and contained within interconnected spatial discs, that transfer the totality of the matter they contain to one other in a sequential manner. Hence, big bang explosions. Finally, because the nature of spatial discs is discrete and flexible, the universe will not expand forever. (shrink)
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  4. The Collapse of Supertasks.Gustavo E. Romero - 2014 - Foundations of Science 19 (2):209-216.
    A supertask consists in the performance of an infinite number of actions in a finite time. I show that any attempt to carry out a supertask will produce a divergence of the curvature of spacetime, resulting in the formation of a black hole. I maintain that supertaks, contrarily to a popular view among philosophers, are physically impossible. Supertasks, literally, collapse under their own weight.
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  5. Logic, mathematics, physics: from a loose thread to the close link: Or what gravity is for both logic and mathematics rather than only for physics.Vasil Penchev - 2023 - Astrophysics, Cosmology and Gravitation Ejournal 2 (52):1-82.
    Gravitation is interpreted to be an “ontomathematical” force or interaction rather than an only physical one. That approach restores Newton’s original design of universal gravitation in the framework of “The Mathematical Principles of Natural Philosophy”, which allows for Einstein’s special and general relativity to be also reinterpreted ontomathematically. The entanglement theory of quantum gravitation is inherently involved also ontomathematically by virtue of the consideration of the qubit Hilbert space after entanglement as the Fourier counterpart of pseudo-Riemannian space. Gravitation can be (...)
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  6. Generation of Biological Patterns and Form: Some Physical, Mathematical and Logical Aspects.Alfred Gierer - 1981 - Progress in Biophysics and Molecular Biology 37 (1):1-48.
    While many different mechanisms contribute to the generation of spatial order in biological development, the formation of morphogenetic fields which in turn direct cell responses giving rise to pattern and form are of major importance and essential for embryogenesis and regeneration. Most likely the fields represent concentration patterns of substances produced by molecular kinetics. Short range autocatalytic activation in conjunction with longer range “lateral” inhibition or depletion effects is capable of generating such patterns (Gierer and Meinhardt, 1972). Non-linear reactions are (...)
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  7. Fondamenti geometrici e problemi filosofici dello spazio-tempo.Luciano Boi - 2012 - Isonomía. Revista de Teoría y Filosofía Del Derecho:1-37.
    The answer to some of the longstanding issues in the 20th century theoretical physics, such as those of the incompatibility between general relativity and quantum mechanics, the broken symmetries of the electroweak force acting at the subatomic scale and the missing mass of Higgs particle, and also those of the cosmic singularity and the black matter and energy, appear to be closely related to the problem of the quantum texture of space-time and the fluctuations of its underlying geometry. Each region (...)
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  8. Identity, space-time, and cosmology.Jan Faye - 2008 - In Dennis Geert Bernardus Johan Dieks (ed.), The Ontology of Spacetime II. Elsevier. pp. 39-57.
    Modern cosmology treats space and time, or rather space-time, as concrete particulars. The General Theory of Relativity combines the distribution of matter and energy with the curvature of space-time. Here space-time appears as a concrete entity which affects matter and energy and is affected by the things in it. I question the idea that space-time is a concrete existing entity which both substantivalism and reductive relationism maintain. Instead I propose an alternative view, which may be called non-reductive relationism, by (...)
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  9. Reinterpreting Relativity: Using the Equivalence Principle to Explain Away Cosmological Anomalies.Marcus Arvan - manuscript
    According to the standard interpretation of Einstein’s field equations, gravity consists of mass-energy curving spacetime, and an additional physical force or entity—denoted by Λ (the ‘cosmological constant’)—is responsible for the Universe’s metric-expansion. Although General Relativity’s direct predictions have been systematically confirmed, the dominant cosmological model thought to follow from it—the ΛCDM (Lambda cold dark matter) model of the Universe’s history and composition—faces considerable challenges, including various observational anomalies and experimental failures to detect dark matter, dark energy, or inflation-field candidates. This (...)
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  10. A pressure-reversible cellular mechanism of general anesthetics capable of altering a possible mechanism of consciousness.Kunjumon Vadakkan - 2015 - Springerplus 4:1-17.
    Different anesthetics are known to modulate different types of membrane-bound receptors. Their common mechanism of action is expected to alter the mechanism for consciousness. Consciousness is hypothesized as the integral of all the units of internal sensations induced by reactivation of inter-postsynaptic membrane functional LINKs during mechanisms that lead to oscillating potentials. The thermodynamics of the spontaneous lateral curvature of lipid membranes induced by lipophilic anesthetics can lead to the formation of non-specific inter-postsynaptic membrane functional LINKs by different mechanisms. (...)
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  11. “Visualizing High-Dimensional Loss Landscapes with Hessian Directions”.Lucas Böttcher & Gregory Wheeler - forthcoming - Journal of Statistical Mechanics: Theory and Experiment.
    Analyzing geometric properties of high-dimensional loss functions, such as local curvature and the existence of other optima around a certain point in loss space, can help provide a better understanding of the interplay between neural network structure, implementation attributes, and learning performance. In this work, we combine concepts from high-dimensional probability and differential geometry to study how curvature properties in lower-dimensional loss representations depend on those in the original loss space. We show that saddle points in the original (...)
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  12. Imprints in time: towards a moderately robust past.Michael Tze-Sung Longenecker - 2018 - Philosophical Studies 175 (10):2429-2446.
    Presentism says that only present objects exist. But the view has trouble grounding past-tensed truths like “dinosaurs existed”. Standard Eternalism grounds those truths by positing the existence of past objects—like dinosaurs. But Standard Eternalism conflicts with the intuition that there is genuine change—the intuition that there once were dinosaurs and no longer are any. I offer a novel theory of time—‘The Imprint’—that does a better job preserving both the grounding and genuine change intuitions. The Imprint says that the past and (...)
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  13. ARE DARK MATTER AND DARK ENERGY OPPOSITE EFFECTS OF THE QUANTUM VACUUM? Guillen - manuscript
    In the standard model of cosmology, λCDM, were introduced to explain the anomalies of the orbital velocities of galaxies in clusters highest according estimated by General Relativity the dark matter and the accelerated expansion of the universe the dark energy. The model λCDM is based in the equations of the General Relativity that of the total mass-energy of the universe assigns 4.9% to matter (including only baryonic matter), 26.8%, to dark matter and 68.3% to dark energy adjusted according observed in (...)
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  14. Perverted Space-Time Geodesy in Einstein’s Views on Geometry.Mario Bacelar Valente - 2018 - Philosophia Scientiae 22:137-162.
    A perverted space-time geodesy results from the idea of variable rods and clocks, whose length and rates are taken to be affected by the gravitational field. By contrast, what we might call a concrete geodesy relies on the idea of invariable unit-measuring rods and clocks. Indeed, this is a basic assumption of general relativity. Variable rods and clocks lead to a perverted geodesy, in the sense that a curved space-time may be seen as a result of a departure from the (...)
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  15. On the uncertainty principle in Rindler and Friedmann spacetimes.Thomas Schürmann - 2020 - European Physical Journal C 80.
    We revise the extended uncertainty relations for the Rindler and Friedmann spacetimes recently discussed by Dabrowski and Wagner in [9]. We reveal these results to be coordinate dependent expressions of the invariant uncertainty relations recently derived for general 3-dimensional spaces of constant curvature in [10]. Moreover, we show that the non-zero minimum standard deviations of the momentum in [9] are just artifacts caused by an unfavorable choice of coordinate systems which can be removed by standard arguments of geodesic completion.
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  16. Are the waves detected by LIGO the waves according to Einstein, Pirani, Bondi, Trautmann, Kopeikin or what are they?Alfonso Guillen Gomez - manuscript
    From the geometric formulation of gravity, according to the Einstein-Grosmann-Hilbert equations, of November 1915, as the geodesic movement in the semirimennian manifold of positive curvature, spacetime, where due to absence of symmetries, the conservation of energy-impulse is not possible taking together the material processes and that of the gravitational geometric field, however, given those symmetries in the flat Minkowski spacetime, using the De Sitter model, Einstein linearizing gravitation, of course, really in the absence of gravity, in 1916, purged of (...)
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  17. On momentum operators given by Killing vectors whose integral curves are geodesics.Thomas Schürmann - 2022 - Physics 4 (4): 1440-1452.
    We consider momentum operators on intrinsically curved manifolds. Given that the momentum operators are Killing vector fields whose integral curves are geodesics, it is shown that the corresponding manifold is either flat, or otherwise of compact type with positive constant sectional curvature and dimension equal to 1, 3 or 7. Explicit representations of momentum operators and the associated Casimir element will be discussed for the 3-sphere. It will be verified that the structure constants of the underlying Lie algebra are (...)
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  18. Time's Arrow in a Quantum Universe: On the Status of Statistical Mechanical Probabilities.Eddy Keming Chen - 2020 - In Valia Allori (ed.), Statistical Mechanics and Scientific Explanation: Determinism, Indeterminism and Laws of Nature. Singapore: World Scientific. pp. 479–515.
    In a quantum universe with a strong arrow of time, it is standard to postulate that the initial wave function started in a particular macrostate---the special low-entropy macrostate selected by the Past Hypothesis. Moreover, there is an additional postulate about statistical mechanical probabilities according to which the initial wave function is a ''typical'' choice in the macrostate. Together, they support a probabilistic version of the Second Law of Thermodynamics: typical initial wave functions will increase in entropy. Hence, there are two (...)
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  19. On the construction of the properties of discrete space.Sydney Ernest Grimm - manuscript
    The proposed existence of relative time and the curvature of space – both combined into the concept of spacetime – influences the search for an adequate theoretical model that can describe the structure of space in an accurate way. The aim of building space is to develop a quantum theory of gravitation. This paper investigate the theoretical problems that have their origin in the concepts that are at the basis of phenomenological physics.
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  20. DNS Analysis on the Indirect Relationship between the Local Burning Velocity and the Flame Displacement Speed of Turbulent Premixed Flames.Kazuya Tsuboi - 2014 - Open Journal of Fluid Dynamics 4 (3):288-297.
    The local burning velocity and the flame displacement speed are the dominant properties in the mechanism of turbulent premixed combustion. The flame displacement speed and the local burning velocity have been investigated separately, because the flame displacement speed can be used for the discussion of flame-turbulence interactions and the local burning velocity can be used for the discussion of the inner structure of turbulent premixed flames. In this study, to establish the basis for the discussion on the effects of turbulence (...)
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  21. Solved what spacetime is?Alfonso Guillen Gomez - manuscript
    In this essay the author overcomes the theoretical contradiction between General Relativity that defines the gravitational field as a geometric aspect of spacetime, either as potential or curvature, and Quantum Gravity that defines it as a fundamental force of interaction, with the change in the conception of spacetime of structural geometric property from the gravitational field, to the conception of spacetime structural geometric property of matter in motion. Spacetime is not a continent of matter (Substantialism) but rather is contained (...)
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  22. Epistemology of Canonical Quantum Gravity - Loop Quantum Gravity.Nicolae Sfetcu - manuscript
    In the interpretation of canonical quantum gravity (CQG), gravity appears as a geometric pseudoforce, is reduced to spacetime geometry and becomes a simple effect of spacetime curvature. The scale at which quantum gravitational effects occur is determined by the different physical constants of fundamental physics: h, c and G, which characterize quantum, relativistic and gravitational phenomena. By combining these constants, we obtain the Planck constants at which the effects of quantum gravity must manifest. Loop quantum gravity attempts to unify (...)
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  23. Ontology of Gravitational Singularities.Nicolae Sfetcu - manuscript
    General relativity allows singularities, and we need to understand the ontology of singularities if we want to understand the nature of space and time in the present universe. Although some physicists believe that singularities indicate a failure of general relativity, others believe that singularities open a new horizon in cosmology, with real physical phenomena that can help deepen our understanding of the world. From the definitions of singularities, most known are the possibility that some spacetimes contain incomplete paths (most accepted), (...)
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  24. Classic gravitational tests of post-Einsteinian theories.Nicolae Sfetcu - manuscript
    Albert Einstein proposed three tests of general relativity, later named the classic tests of general relativity, in 1916: the precession of the perihelion of Mercury's orbit, sun light deflection, and the gravitational redshift of the light. For gravitational testing, the indirect effects of gravity are always used, usually particles that are influenced by gravity. In the presence of gravity, the particles move along curved geodesic lines. The sources of gravity that cause the curvature of spacetime are material bodies, depending (...)
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  25. A BRIEF OUTLINE OF THE POSSIBLE BASICS OF COSMOLOGY IN THE 22nd CENTURY, AND WHAT IT MEANS FOR RELIGION.Rodney Bartlett - manuscript
    This article’s conclusion is that the theories of Einstein are generally correct and will still be relevant in the next century (there will be modifications necessary for development of quantum gravity). Those Einsteinian theories are Special Relativity, General Relativity, and the title of a paper he published in 1919 which asked if gravitation plays a role in the composition of elementary particles of matter. This paper was the bridge between General Relativity and the Unified Field Theory he sought during the (...)
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  26. Mind an hourglass at the bed of time-space continuum.Reza Assadi - manuscript
    In this paper a new model of mind is proposed, to do so, at first it was assumed that our physical world a new structure and the mind defined in this context. In this model, the planets are massive curvature of time-space continuum that has made a trapping physical reality that we are located within. Then the mind is defined as an hourglass structure with half bulb within the physical reality and half out of it. This model with attention (...)
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  27. Remarks on Mӧller mistaken famous paper from 1943.Jaykov Foukzon - manuscript
    Einstein field equations was originally derived by Einstein in 1915 in respect with canonical formalism of Riemann geometry,i.e. by using the classical sufficiently smooth metric tensor, smooth Riemann curvature tensor, smooth Ricci tensor,smooth scalar curvature, etc.. However have soon been found singular solutions of the Einstein field equations with degenerate and singular metric tensor and singular Riemann curvature tensor. These degenerate and singular solutions of the Einstein field equations was formally accepted by main part of scientific community (...)
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  28. Gravity, Metaphysics or Physics ?Alfonso Leon Guillen Gomez - 2013 - International Journal of Fundamental Physical Sciences 3 (4):68 - 74.
    Gravity is the foundation of the current physical paradigm. Due to that gravity is strongly linked to the curvature of space-time, we research that it lacks of a valid physical concept of space-time, nevertheless that from the science philosophy, via substantivalism, it has tried respond. We found that is due to that the gnoseological process applied from the general relativity, necessarily us leads to metaphysic because ontologically space-time is a metaphysical entity. Thus, we arrive to the super substantivalism that (...)
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  29. Mathematical Nature of Reality, Plus Gravitation-Electromagnetism Unification, Derived from Revised Gravitational Tidal Forces and Mass-from-Gravity Concept.Rodney Bartlett - manuscript
    This article had its beginning with Einstein's 1919 paper "Do gravitational fields play an essential role in the structure of elementary particles?" Together with General Relativity's statement that gravity is not a pull but is a push caused by the curvature of space-time, a hypothesis for Earth's ocean tides was developed that does not solely depend on the Sun and Moon as Kepler and Newton believed. It also borrows from Galileo. The breakup of planets and asteroids by white dwarfs, (...)
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  30. Are the waves detected by LIGO the waves according to Einstein, Pirani, Bondi, Trautmann, Kopeikin or what are they?Alfonso Guillen Gomez - manuscript
    From the geometric formulation of gravity, according to the Einstein-Grosmann-Hilbert equations, of November 1915, as the geodesic movement in the semirimennian manifold of positive curvature, spacetime, where due to absence of symmetries, the conservation of energy-impulse is not possible taking together the material processes and that of the gravitational geometric field, however, given those symmetries in the flat Minkowski spacetime, using the De Sitter model, Einstein linearizing gravitation, of course, really in the absence of gravity, in 1916, purged of (...)
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  31. Gravity is a force.Alfonso Leon Guillen Gomez - manuscript
    The General Relativity understands gravity like inertial movement of the free fall of the bodies in curved spacetime of Lorentz. The law of inertia of Newton would be particular case of the inertial movement of the bodies in the spacetime flat of Euclid. But, in the step, of the particular to the general, breaks the law of inertia of Galilei since recovers the rectilinear uniform movement but not the repose state, unless the bodies have undergone their union, although, the curved (...)
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  32. Gravity is a quantum force.Alfonso Leon Guillen Gomez - manuscript
    The General Relativity understands gravity like inertial movement of the free fall of the bodies in curved spacetime of Lorentz. The law of inertia of Newton would be particular case of the inertial movement of the bodies in the spacetime flat of Euclid. But, in the step, from general to particular, breaks the law of inertia of Galilei since recovers apparently the rectilinear uniform movement but not the repose state, unless the bodies have undergone their collapse, although, the curved spacetime (...)
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  33. The role of virtual work in Levi-Civita’s parallel transport.Giuseppe Iurato & Giuseppe Ruta - 2015 - Proceedings of Applied Mathematics and Mechanics 15:705-706.
    According to current history of science, Levi-Civita introduced parallel transport solely to give a geometrical interpretation to the covariant derivative of absolute differential calculus. Levi-Civita, however, searched a simple computation of the curvature of a Riemannian manifold, basing on notions of the Italian school of mathematical physics of his time: holonomic constraints, virtual displacements and work, which so have a remarkable, if not dominant, role in the origin of parallel transport.
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  34. Mathematical Nature of Gravity, Which General Relativity Says is Space-Time : Topology Unites With the Matrix, E=mc2, Advanced Waves, Wick Rotation, Dark Matter & Higher Dimensions.Rodney Bartlett - manuscript
    General Relativity says gravity is a push caused by space-time's curvature. Combining General Relativity with E=mc2 results in distances being totally deleted from space-time/gravity by future technology, and in expansion or contraction of the universe as a whole being eliminated. The road to these conclusions has branches shining light on supersymmetry and superconductivity. This push of gravitational waves may be directed from intergalactic space towards galaxy centres, helping to hold galaxies together and also creating supermassive black holes. Together with (...)
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  35. ARE DARK MATTER AND DARK ENERGY OPPOSITE EFFECTS OF THE QUANTUM VACUUM?Alfonso Leon Guillen Gomez - manuscript
    In the standard model of cosmology, λCDM, were introduced to explain the anomalies of the orbital velocities of galaxies in clusters highest according estimated by General Relativity the dark matter and the accelerated expansion of the universe the dark energy. The model λCDM is based in the equations of the General Relativity that of the total mass-energy of the universe assigns 4.9% to matter (including only baryonic matter), 26.8%, to dark matter and 68.3% to dark energy adjusted according observed in (...)
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  36. A Curiosity about Newtonian Gravity v. 2.0.Paul Merriam - manuscript
    We give a very curious curiosity about Newtonian Gravity.
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