Log in

Relevant bibliographies by topics / One form metric / Journal articles

To see the other types of publications on this topic, follow the link: One form metric.

Journal articles on the topic 'One form metric'

Author: Grafiati

Published: 3 June 2025

Last updated: 31 July 2025

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'One form metric.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Zhao, Wen Jing, Yan Yan, Li Nan Shi та Bo Chao Qu. "The Projectively Flat Conditions of One Special Class (α, β)-Metrics". Advanced Materials Research 756-759 (вересень 2013): 2528–32. http://dx.doi.org/10.4028/www.scientific.net/amr.756-759.2528.

Full text

Abstract:

The-metric is an important class of Finsler metrics including Randers metric as the simplest class, and many people research the Randers metrics. In this paper, we study a new class of Finsler metrics in the form ,Whereis a Riemannian metric, is a 1-form. Bengling Li had introduced the projective flat of the-Metric F. We find another method which is about flag curvature to prove the projective flat conditions of this kind of-metric.

APA, Harvard, Vancouver, ISO, and other styles

2

Heefer, Sjors, Christian Pfeifer, Jorn van Voorthuizen, and Andrea Fuster. "On the metrizability of m-Kropina spaces with closed null one-form." Journal of Mathematical Physics 64, no. 2 (2023): 022502. http://dx.doi.org/10.1063/5.0130523.

Full text

Abstract:

We investigate the local metrizability of Finsler spaces with m-Kropina metric F = α1+ m β− m, where β is a closed null one-form. We show that such a space is of Berwald type if and only if the (pseudo-)Riemannian metric α and one-form β have a very specific form in certain coordinates. In particular, when the signature of α is Lorentzian, α belongs to a certain subclass of the Kundt class and β generates the corresponding null congruence, and this generalizes in a natural way to arbitrary signature. We use this result to prove that the affine connection on such an m-Kropina space is locally m

APA, Harvard, Vancouver, ISO, and other styles

3

Elgendi, Salah G. "Parallel one forms on special Finsler manifolds." AIMS Mathematics 9, no. 12 (2024): 34356–71. https://doi.org/10.3934/math.20241636.

Full text

Abstract:

<p>In this paper, we investigated the existence of parallel 1-forms on specific Finsler manifolds. We demonstrated that Landsberg manifolds admitting a parallel 1-form had a mean Berwald curvature of rank of at most $ n-2 $. As a result, Landsberg surfaces with parallel 1-forms were necessarily Berwaldian. We further established that the metrizability freedom of the geodesic spray for Landsberg metrics with parallel 1-forms was at least $ 2 $. We figured out that some special Finsler metrics did not admit a parallel 1-form. Specifically, no parallel 1-form was admitted for any Finsler me

APA, Harvard, Vancouver, ISO, and other styles

4

Zohrehvand, M., та H. Maleki. "On general (α,β)-metrics of Landsberg type". International Journal of Geometric Methods in Modern Physics 13, № 06 (2016): 1650085. http://dx.doi.org/10.1142/s0219887816500857.

Full text

Abstract:

In this paper, we study a class of Finsler metrics, which are defined by a Riemannian metric [Formula: see text] and a one-form [Formula: see text]. They are called general [Formula: see text]-metrics. We have proven that, every Landsberg general [Formula: see text]-metric is a Berwald metric, under a certain condition. This shows that the hunting for an unicorn, one of the longest standing open problem in Finsler geometry, cannot be successful in the class of general [Formula: see text]-metrics.

APA, Harvard, Vancouver, ISO, and other styles

5

Mandal, Khageshwar. "β-Change of Riemannian Space and Special Cases of one-form β". Journal of Nepal Mathematical Society 1, № 1 (2018): 30–37. http://dx.doi.org/10.3126/jnms.v1i1.42172.

Full text

Abstract:

In this paper, we consider β-change of Finsler metric L given by L = f(L; β), where f is any positively homogeneous function of degree one in L and β. The objectives of the paper are to obtain the β-change of a Riemannian space, projective change of Finsler metric and to discuss the special cases of one-form β.

APA, Harvard, Vancouver, ISO, and other styles

6

Dillen, Franki, Luc Vrancken, and Sahnur Yaprak. "Affine hypersurfaces with parallel cubic form." Nagoya Mathematical Journal 135 (September 1994): 153–64. http://dx.doi.org/10.1017/s0027763000005006.

Full text

Abstract:

As is well known, there exists a canonical transversal vector field on a non-degenerate affine hypersurface M. This vector field is called the affine normal. The second fundamental form associated to this affine normal is called the affine metric. If M is locally strongly convex, then this affine metric is a Riemannian metric. And also, using the affine normal and the Gauss formula one can introduce an affine connection ∇ on M which is called the induced affine connection. Thus there are in general two different connections on M: one is the induced connection ∇ and the other is the Levi Civita

APA, Harvard, Vancouver, ISO, and other styles

7

Li, Wenbin, Yang Gao, Lei Wang, Luping Zhou, Jing Huo, and Yinghuan Shi. "OPML: A one-pass closed-form solution for online metric learning." Pattern Recognition 75 (March 2018): 302–14. http://dx.doi.org/10.1016/j.patcog.2017.03.016.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Kushwaha, Ramdayal Singh, та Gauree Shanker. "On the ℒ-duality of a Finsler space with exponential metric αeβ/α". Acta Universitatis Sapientiae, Mathematica 10, № 1 (2018): 167–77. http://dx.doi.org/10.2478/ausm-2018-0014.

Full text

Abstract:

Abstract The (α, β)-metrics are the most studied Finsler metrics in Finsler geometry with Randers, Kropina and Matsumoto metrics being the most explored metrics in modern Finsler geometry. The ℒ-dual of Randers, Kropina and Matsumoto space have been introduced in [3, 4, 5], also in recent the ℒ-dual of a Finsler space with special (α, β)-metric and generalized Matsumoto spaces have been introduced in [16, 17]. In this paper, we find the ℒ-dual of a Finsler space with an exponential metric αeβ/α, where α is Riemannian metric and β is a non-zero one form.

APA, Harvard, Vancouver, ISO, and other styles

9

Soleiman, A., and S. G. Elgendi. "Generalized second approximation Matsumoto metric." Journal of Dynamical Systems and Geometric Theories 22, no. 1&2 (2024): 65–85. https://doi.org/10.47974/jdsgt-2024-005.

Full text

Abstract:

In this paper, we tackle a more general coordinate-free investigation of the second approximation Matsumoto metric. Specifically, we establish various geometric objects corresponding the second approximation Matsumoto metric L̃(x,y) = L + B + B2/L + B3/L2 in terms of the objects of L with a Finsler structure (M,L) and a one form B. Here we consider L is Finslerian and so we call L̃ the generalized second approximation Matsumoto metric. We describe the metric tensor of L̃ and its nondegeneracy. We limit the one form B to a one form associated with a concurent π-vector field in order to determin

APA, Harvard, Vancouver, ISO, and other styles

10

Ahmad, Daud, and Kashif Habib. "Homotheties of a Class of Spherically Symmetric Space-Time Admitting G3 as Maximal Isometry Group." Advances in Mathematical Physics 2018 (2018): 1–8. http://dx.doi.org/10.1155/2018/8195208.

Full text

Abstract:

The homotheties of spherically symmetric space-time admitting G4, G6, and G10 as maximal isometry groups are already known, whereas, for the space-time admitting G3 as isometry groups, the solution in the form of differential constraints on metric coefficients requires further classification. For a class of spherically symmetric space-time admitting G3 as maximal isometry groups without imposing any restriction on the stress-energy tensor, the metrics along with their corresponding homotheties are found. In one case, the metric is found along with its homothety vector that satisfies an additio

APA, Harvard, Vancouver, ISO, and other styles

11

Vitter, Al. "Hermitian–Einstein metrics and jumping lines forSp(n+1)-homogeneous bundles over ℙ2n+1". Mathematical Proceedings of the Cambridge Philosophical Society 114, № 3 (1993): 443–51. http://dx.doi.org/10.1017/s0305004100071735.

Full text

Abstract:

Stable holomorphic vector bundles over complex projective space ℙnhave been studied from both the differential-geometric and the algebraic-geometric points of view.On the differential-geometric side, the stability ofE-→ ℙncan be characterized by the existence of a unique hermitian–Einstein metric onE, i.e. a metric whose curvature matrix has trace-free part orthogonal to the Fubini–Study Kähler form of ℙn(see [6], [7], and [13]). Very little is known about this metric in general and the only explicit examples are the metrics on the tangent bundle of ℙnand the nullcorrelation bundle (see [9] an

APA, Harvard, Vancouver, ISO, and other styles

12

Dillen, Franki, та Luc Vrancken. "3-dimensional affine hypersurfaces in ℝ4 with parallel cubic form". Nagoya Mathematical Journal 124 (грудень 1991): 41–53. http://dx.doi.org/10.1017/s0027763000003767.

Full text

Abstract:

In this paper, we study 3-dimensional locally strongly convex affine hypersurfaces in ℝ4. Since the publication of Blaschke’s book [B] in the early twenties, it is well-known that on a nondegenerate affine hyper-surface M there exists a canonical transversal vector field called the affine normal. The second fundamental form associated to the affine normal is called the affine metric. In the special case that M is locally strongly convex, this affine metric is a Riemannian metric. Also, using the affine normal, by the Gauss formula one can introduce an affine connection on M, called the induced

APA, Harvard, Vancouver, ISO, and other styles

13

CHENG, XINYUE, ZHONGMIN SHEN, and YUSHENG ZHOU. "ON LOCALLY DUALLY FLAT FINSLER METRICS." International Journal of Mathematics 21, no. 11 (2010): 1531–43. http://dx.doi.org/10.1142/s0129167x10006616.

Full text

Abstract:

Locally dually flat Finsler metrics arise from information geometry. Such metrics have special geometric properties. In this paper, we characterize locally dually flat and projectively flat Finsler metrics and study a special class of Finsler metrics called Randers metrics which are expressed as the sum of a Riemannian metric and a one-form. We find some equations that characterize locally dually flat Randers metrics and classify those with isotropic S-curvature.

APA, Harvard, Vancouver, ISO, and other styles

14

KATSUKI, MIYUKI, AKIO SUGAMOTO, and SHIN’ICHI NOJIRI. "TWO-FORM GRAVITY AND THE GENERATION OF SPACE-TIME." International Journal of Modern Physics A 11, no. 17 (1996): 3033–48. http://dx.doi.org/10.1142/s0217751x96001474.

Full text

Abstract:

In the framework of the two-form gravity, which is classically equivalent to the Einstein gravity, the one-loop effective potential for the conformal factor of metric is calculated in the finite volume and in the finite temperature by choosing a temporal gauge condition. There appears a quartically divergent term which cannot be removed by the renormalization of the cosmological term and we find there is only one nontrivial minimum in the effective potential. If the cutoff scale has a physical meaning, e.g. the Planck scale coming from string theory, this minimum might explain why the space-ti

APA, Harvard, Vancouver, ISO, and other styles

15

Ontaneda, Pedro. "Deforming an є-close-to-hyperbolic metric to a hyperbolic metric". Proceedings of the Royal Society of Edinburgh: Section A Mathematics 148, № 3 (2018): 629–41. http://dx.doi.org/10.1017/s0308210518000021.

Full text

Abstract:

We show how to deform a metric of the form g = gr + dr2 to a metric = Hr + dr2, which is a hyperbolic metric for r less than some fixed λ, and coincides with g for r large. Here by hyperbolic metric we mean a metric of constant sectional curvature equal to -1. We study the extent to which is close to hyperbolic everywhere, if we assume g is close to hyperbolic. A precise definition of the close to hyperbolic concept is given. We also deal with a one-parameter version of this problem. The results in this paper are used in the problem of smoothing Charney–Davis strict hyperbolizations.

APA, Harvard, Vancouver, ISO, and other styles

16

MASCHLER, GIDEON. "METRIC PAIRS AND THE FUTAKI CHARACTER." International Journal of Mathematics 13, no. 01 (2002): 1–9. http://dx.doi.org/10.1142/s0129167x02001125.

Full text

Abstract:

The non-vanishing of the Futaki character gives an obstruction to the existence of Kähler metrics of constant scalar curvature, having a Kähler form belonging to a fixed Kähler class [4, 6]. It is shown that, in combination with the resolution of the Calabi conjecture [18], one has an analogous obstruction on pairs of metrics having Kähler forms belonging to a fixed pair of Kähler classes. If the difference of the Futaki characters on two classes of fixed total volume does not vanish identically, there cannot exist a pair of metrics, with Kähler forms in these classes, having the same Ricci fo

APA, Harvard, Vancouver, ISO, and other styles

17

Palmer, J. H., and R. B. Mann. "Post-Newtonian expansion of an algebraically extended theory of gravity." Canadian Journal of Physics 69, no. 5 (1991): 641–54. http://dx.doi.org/10.1139/p91-108.

Full text

Abstract:

The post-Newtonian expansion is analyzed for an algebraically extended theory of gravity equivalent to a theory with a real, nonsymmetric metric, previously referred to as Algebraically Extended Hilbert Gravity (AHG). The hermiticity of the algebra-valued covariant and contravariant metrics is found to constrain the form of the expansion of the antisymmetric part of the real metric to one of two possibilities. Both of these display a qualitatively new technical feature: the lowest order equations are nonlinear, depriving the post-Newtonian expansion of its greatest asset. In one case, they lea

APA, Harvard, Vancouver, ISO, and other styles

18

Lipatova, S. Yu. "Metrics transformations preserving the types of one-dimensional minimal fillings." Filomat 33, no. 4 (2019): 1081–89. http://dx.doi.org/10.2298/fil1904081l.

Full text

Abstract:

Given a class F of metric spaces and a family of transformations T of a metric, one has to describe a family of transformations T' ? T that transfer F into itself and preserve some types of minimal fillings. The article considers four cases. First, when F is the class of all finite metric spaces, T = {(M,?) ? (M, f??) | f : R>0 ? R>0}, and the elements of T' preserve all non-degenerate types of minimal fillings of four-point metric spaces and finite non-degenerate stars, and we prove that T' = {(M,?) ? (M,?? + a):a > ?a?}. Second, when F is the class of all finite metric spaces, the c

APA, Harvard, Vancouver, ISO, and other styles

19

ALVES, M. "A SIMPLE LINE ELEMENT FOR THE DILATON GRAVITY." International Journal of Modern Physics D 10, no. 04 (2001): 575–78. http://dx.doi.org/10.1142/s0218271801001323.

Full text

Abstract:

The metric for the two-dimensional dilaton gravity can be writen in an alternative form, similar to the two-dimensional Schwarzschild metric, and allow us the identification of some quantitiies with those equivalent in the Schwarzschild solution. This new form, however, presents a nonphysical singularity at the horizon in the same way that in the realistic four dimensional case. We show a procedure to eliminate this horizon singularity and, as an application, the resulting metric is used to obtain the associated Hawking temperature. We discuss also some differents between this metric and the S

APA, Harvard, Vancouver, ISO, and other styles

20

Baines, Joshua, Thomas Berry, Alex Simpson, and Matt Visser. "Painlevé–Gullstrand form of the Lense–Thirring Spacetime." Universe 7, no. 4 (2021): 105. http://dx.doi.org/10.3390/universe7040105.

Full text

Abstract:

The standard Lense–Thirring metric is a century-old slow-rotation large-distance approximation to the gravitational field outside a rotating massive body, depending only on the total mass and angular momentum of the source. Although it is not an exact solution to the vacuum Einstein equations, asymptotically the Lense–Thirring metric approaches the Kerr metric at large distances. Herein we shall discuss a specific variant of the standard Lense–Thirring metric, carefully chosen for simplicity, clarity, and various forms of improved mathematical and physical behaviour, (to be more carefully defi

APA, Harvard, Vancouver, ISO, and other styles

21

Aslam, Muhammad Suhail, Mohammad Showkat Rahim Chowdhury, Liliana Guran, Manar A. Alqudah, and Thabet Abdeljawad. "Fixed point theory in complex valued controlled metric spaces with an application." AIMS Mathematics 7, no. 7 (2022): 11879–904. http://dx.doi.org/10.3934/math.2022663.

Full text

Abstract:

<abstract><p>In this article we have introduced a metric named complex valued controlled metric type space, more generalized form of controlled metric type spaces. This concept is a new extension of the concept complex valued $ b $-metric type space and this one is different from complex valued extended $ b $-metric space. Using the idea of this new metric, some fixed point theorems involving Banach, Kannan and Fisher contractions type are proved. Some examples togetheran application are described to sustain our primary results.</p></abstract>

APA, Harvard, Vancouver, ISO, and other styles

22

FITRIANI, FENNY, and SARI CAHYANINGTIAS. "GRAF DUAL ANTIPRISMA DAN DIMENSI METRIKNYA." E-Jurnal Matematika 10, no. 1 (2021): 6. http://dx.doi.org/10.24843/mtk.2021.v10.i01.p313.

Full text

Abstract:

Dual graph is one form of graph that can only be formed from graphs whose edges do not intersect each other. One of the graphs that can be converted into dual graphs is the antiprism graph Amn . Antiprism graph Amn is a graph that is formed from the absorption of vertices in the prism graph Pmn . One of the operations performed on a graph is finding the metric dimension of the graph. These metric dimensions are looking to find a minimum cardinality value of the graph. This article discusses the metric dimensions of the dual antiprism graph A'm,n. Dimanesion of dual antiprism graph A'm,n is obt

APA, Harvard, Vancouver, ISO, and other styles

23

Mönkkönen, Keijo. "Boundary rigidity for Randers metrics." Annales Fennici Mathematici 47, no. 1 (2021): 89–102. http://dx.doi.org/10.54330/afm.112492.

Full text

Abstract:

 If a non-reversible Finsler norm is the sum of a reversible Finsler norm and a closed 1-form, then one can uniquely recover the 1-form up to potential fields from the boundary distance data. We also show a boundary rigidity result for Randers metrics where the reversible Finsler norm is induced by a Riemannian metric which is boundary rigid. Our theorems generalize Riemannian boundary rigidity results to some non-reversible Finsler manifolds. We provide an application to seismology where the seismic wave propagates in a moving medium.

APA, Harvard, Vancouver, ISO, and other styles

24

Druta-Romaniuc, Simona-Luiza. "Quasi-Statistical Schouten–van Kampen Connections on the Tangent Bundle." Mathematics 11, no. 22 (2023): 4614. http://dx.doi.org/10.3390/math11224614.

Full text

Abstract:

We determine the general natural metrics G on the total space TM of the tangent bundle of a Riemannian manifold (M,g) such that the Schouten–van Kampen connection ∇¯ associated to the Levi-Civita connection of G is (quasi-)statistical. We prove that the base manifold must be a space form and in particular, when G is a natural diagonal metric, (M,g) must be locally flat. We prove that there exist one family of natural diagonal metrics and two families of proper general natural metrics such that (TM,∇¯,G) is a statistical manifold and one family of proper general natural metrics such that (TM∖{0

APA, Harvard, Vancouver, ISO, and other styles

25

Fino, Anna, Gueo Grantcharov, and Luigi Vezzoni. "Astheno–Kähler and Balanced Structures on Fibrations." International Mathematics Research Notices 2019, no. 22 (2017): 7093–117. http://dx.doi.org/10.1093/imrn/rnx337.

Full text

Abstract:

Abstract We study the existence of three classes of Hermitian metrics on certain types of compact complex manifolds. More precisely, we consider balanced, strong Kähler with torsion (SKT), and astheno-Kähler metrics. We prove that the twistor spaces of compact hyperkähler and negative quaternionic-Kähler manifolds do not admit astheno-Kähler metrics. Then we provide a construction of astheno-Kähler structures on torus bundles over Kähler manifolds leading to new examples. In particular, we find examples of compact complex non-Kähler manifolds which admit a balanced and an astheno-Kähler metric

APA, Harvard, Vancouver, ISO, and other styles

26

Garcia de Andrade, L. C. "Unified theories metrics and primordial magnetic fields in Riemann–Cartan spacetime." International Journal of Geometric Methods in Modern Physics 18, no. 05 (2021): 2150072. http://dx.doi.org/10.1142/s0219887821500729.

Full text

Abstract:

Several spacetime metrics in teleparallel geometry of Einstein like unified field theory (UFT) are presented. Cosmic magnetic fields are obtained in terms of the early universe torsion and other stages of the universe. For example, in one of the metrics, integration of the 2-form torsion 0-component is written in terms of magnetic flux, from Faraday’s induced equation. These ideas were obtained from a recent paper we published [Class. Quantum Grav. (2015)] on non-stationary teleparallel metrics, where at coherent length of [Formula: see text] a magnetic field of [Formula: see text] is obtained

APA, Harvard, Vancouver, ISO, and other styles

27

Shukla, H. S., та A. P. Tiwari. "Conformal Correspondence of Finsler Spaces with Special(α,β)-Metric". Journal of the Tensor Society 6, № 01 (2007): 35–41. http://dx.doi.org/10.56424/jts.v6i01.10462.

Full text

Abstract:

The purpose of the present paper is to discuss the conformal transformation of a Finsler space with a special (α,β) metric given by L2 = c1α2+2c2αβ+c3β2, where c1, c2, c3 are constants,αis Riemannian metric andβis one form. We have proved that for such a Finsler metric, the Berwald spaces, the locally Minkowski spaces and the projectively flat spaces are not invariant under nonhomothetic conformal transformation.

APA, Harvard, Vancouver, ISO, and other styles

28

Ren, Ruonan, and Yongming Li. "Uncertainty relation based on metric-adjusted skew information with quantum memory." Laser Physics 33, no. 1 (2022): 015203. http://dx.doi.org/10.1088/1555-6611/aca4cb.

Full text

Abstract:

Abstract The uncertainty principle is one of the most essential features of quantum mechanics. Recently, uncertainty relations of skew information have been widely studied. In this paper, general and conditional uncertainty relations based on metric-adjusted skew information are put forward to study the case of the uncertainty relation with the existence of a quantum memory for the bipartite quantum system. These uncertainty relations include the product form and the sum form. The results show that the lower bounds contain two parts: one is characterizing the degree of compatibility of two mea

APA, Harvard, Vancouver, ISO, and other styles

29

DAHL, MATIAS F. "A RESTATEMENT OF THE ALGEBRAIC CLASSIFICATION OF AREA METRICS ON 4-MANIFOLDS." International Journal of Geometric Methods in Modern Physics 09, no. 05 (2012): 1250046. http://dx.doi.org/10.1142/s0219887812500466.

Full text

Abstract:

An area metric is a [Formula: see text]-tensor with certain symmetries on a 4-manifold that represents a non-dissipative linear electromagnetic medium. A recent result by Schuller, Witte and Wohlfarth gives a pointwise algebraic classification for such area metrics. This result is similar to the Jordan normal form theorem for [Formula: see text]-tensors, and the result shows that pointwise area metrics divide into 23 metaclasses and each metaclass requires two coordinate representations. For the first 7 metaclasses, we show that only one coordinate representation is needed. For the remaining 1

APA, Harvard, Vancouver, ISO, and other styles

30

Santoro, Antonio. "Characterization of Crystal Lattices." Acta Crystallographica Section A Foundations and Advances 70, a1 (2014): C1453. http://dx.doi.org/10.1107/s2053273314085465.

Full text

Abstract:

At present time, crystal lattices are characterized by means of the 44 reduced forms tabulated in Int. Tables for Crystallography, Vol. A, 1983, pag.737. Recently, we have found that this classification can be improved by a more careful analysis of the metric properties of each reduced form. Foe example, we know that the reciprocal cell of a face-centered lattice is body-centerd, and vice-versa. In the orthorhombic system there are two oF reduced forms (#16 and #26) and three oI (#8, 19 and 42) and therefore there is no one to one relationship between direct and reciprocal reduced forms. In fa

APA, Harvard, Vancouver, ISO, and other styles

31

Duggal, K. L., and R. Sharma. "Totally umbilicalCR-submanifolds of Semi-Riemannian Kaehler manifolds." International Journal of Mathematics and Mathematical Sciences 10, no. 3 (1987): 551–55. http://dx.doi.org/10.1155/s0161171287000668.

Full text

Abstract:

We study totally umbilicalCR-submanifolds of a Kaehler manifold carrying a semi-Riemannian metric. It is shown that for dimension of the totally real distribution greater than one, these submanifolds are locally decomposable into a complex and a totally real submanifold of the Kaehler manifold. For dimension equal to one, we show, in particular, that they are endowed with a normal contact metric structure if and only if the second fundamental form is parallel.

APA, Harvard, Vancouver, ISO, and other styles

32

VACARU, S. "ON GENERAL SOLUTIONS OF EINSTEIN EQUATIONS." International Journal of Geometric Methods in Modern Physics 08, no. 01 (2011): 9–21. http://dx.doi.org/10.1142/s0219887811004938.

Full text

Abstract:

We show how the Einstein equations with cosmological constant (and/or various types of matter field sources) can be integrated in a very general form following the anholonomic deformation method for constructing exact solutions in four- and five-dimensional gravity (S. Vacaru, IJGMMP 4 (2007) 1285). In this paper, we prove that such a geometric method can be used for constructing general non-Killing solutions. The key idea is to introduce an auxiliary linear connection which is also metric compatible and completely defined by the metric structure but contains some torsion terms induced nonholo

APA, Harvard, Vancouver, ISO, and other styles

33

Chen, Zhen-Qing, Michael Röckner, Masayoshi Takeda, and Anita Winter. "Recent Developments in Dirichlet Form Theory and Related Fields." Oberwolfach Reports 21, no. 3 (2025): 2425–510. https://doi.org/10.4171/owr/2024/42.

Full text

Abstract:

Theory of Dirichlet forms is one of the main achievements in modern probability theory. It has numerous interactions with other areas of mathematics and sciences. The recent notable developments are its role in the study of Liouville Brownian motion, Gaussian free field, stochastic partial differential equations, stochastic analysis on metric measure spaces, and Markov processes in random environments.The workshop brings together top experts in Dirichlet form theory, stochastic analysis and related fields, with the common theme of developing new foundational methods and their applications to s

APA, Harvard, Vancouver, ISO, and other styles

34

Tiwari, S. K., Brijesh Kumar Maurya та C. P. Maurya. "The conformal β-change of Finsler metric and imbedding classes of their tangent spaces". International Journal of Contemporary Mathematical Sciences 19, № 1 (2024): 15–26. https://doi.org/10.12988/ijcms.2024.91875.

Full text

Abstract:

We have considered the conformal β – change of Finsler metric L given by L ̅ = e^σ f(L,β ), where f is any positively homogeneous function of degree one in L and 1-form β. We have obtained that due to this change of Finsler metric, the imbedding class of their tangent Riemannian space is increased at most by two.

APA, Harvard, Vancouver, ISO, and other styles

35

Manev, Mancho. "Yamabe Solitons on Some Conformal Almost Contact B-Metric Manifolds." Mathematics 10, no. 4 (2022): 658. http://dx.doi.org/10.3390/math10040658.

Full text

Abstract:

A Yamabe soliton is defined on an arbitrary almost-contact B-metric manifold, which is obtained by a contact conformal transformation of the Reeb vector field, its dual contact 1-form, the B-metric, and its associated B-metric. The cases when the given manifold is cosymplectic or Sasaki-like are studied. In this manner, manifolds are obtained that belong to one of the main classes of the studied manifolds. The same class contains the conformally equivalent manifolds of cosymplectic manifolds by the usual conformal transformation of the B-metric on contact distribution. In both cases, explicit

APA, Harvard, Vancouver, ISO, and other styles

36

Chaudhary, Himanshu, Lehel Csillag, and Tiberiu Harko. "Semi-Symmetric Metric Gravity: A Brief Overview." Universe 10, no. 11 (2024): 419. http://dx.doi.org/10.3390/universe10110419.

Full text

Abstract:

We present a review of the Semi-Symmetric Metric Gravity (SSMG) theory, representing a geometric extension of standard general relativity, based on a connection introduced by Friedmann and Schouten in 1924. The semi-symmetric connection is a connection that generalizes the Levi-Civita one by allowing for the presence of a simple form of the torsion, described in terms of a torsion vector. The Einstein field equations are postulated to have the same form as in standard general relativity, thus relating the Einstein tensor constructed with the help of the semi-symmetric connection, with the ener

APA, Harvard, Vancouver, ISO, and other styles

37

Yeung, Dit-Yan, Hong Chang, and Guang Dai. "A Scalable Kernel-Based Semisupervised Metric Learning Algorithm with Out-of-Sample Generalization Ability." Neural Computation 20, no. 11 (2008): 2839–61. http://dx.doi.org/10.1162/neco.2008.05-07-528.

Full text

Abstract:

In recent years, metric learning in the semisupervised setting has aroused a lot of research interest. One type of semisupervised metric learning utilizes supervisory information in the form of pairwise similarity or dissimilarity constraints. However, most methods proposed so far are either limited to linear metric learning or unable to scale well with the data set size. In this letter, we propose a nonlinear metric learning method based on the kernel approach. By applying low-rank approximation to the kernel matrix, our method can handle significantly larger data sets. Moreover, our low-rank

APA, Harvard, Vancouver, ISO, and other styles

38

Khokhlov, S. V., and L. A. Ignatochkina. "Invariance of some classes of almost Hermitian structures concerning to the one-parameter group of diffeomorphisms generated by the Lie vector field." Differential Geometry of Manifolds of Figures, no. 53 (2022): 127–34. http://dx.doi.org/10.5922/0321-4796-2022-53-12.

Full text

Abstract:

Finding the conditions for the invariance of geometric objects under the action of transformation groups is one of the main objects of geometric research. Almost Hermitian structures and structures of the Gray — Hervella classification on smooth manifolds are considered in this paper. All arguments are given using invariant Koszul’s calculus. Conditions for the invariance of the Kähler form in type structures are investigated and it is shown that the Kähler form is covariantly constant with respect to the Lie vector field. Conditions for the invariance of the Riemannian metric under the acti

APA, Harvard, Vancouver, ISO, and other styles

39

Samsonov, Timofey, and Olga Yakimova. "Analysis of the effectiveness of constraining metrics of geometric simplification algorithms based on expert evaluation of line detail." InterCarto. InterGIS 27, no. 2 (2021): 253–67. http://dx.doi.org/10.35595/2414-9179-2021-2-27-253-267.

Full text

Abstract:

The paper reveals dependencies between the character of the line shape and combination of constraining metrics that allows comparable reduction in detail by different geometric simplification algorithms. The study was conducted in a form of the expert survey. geometrically simplified versions of three coastline fragments were prepared using three different geometric simplification algorithms—Douglas-peucker, Visvalingam-Whyatt and Li-Openshaw. Simplification was constrained by similar value of modified hausdorff distance (linear offset) and similar reduction of number of line bends (compressio

APA, Harvard, Vancouver, ISO, and other styles

40

MUKOYAMA, SHINJI, and JEAN-PHILIPPE UZAN. "EMERGENCE OF THE LORENTZIAN STRUCTURE IN CLASSICAL FIELD THEORY." International Journal of Modern Physics D 22, no. 12 (2013): 1342018. http://dx.doi.org/10.1142/s0218271813420182.

Full text

Abstract:

The Lorentzian metric structure allows one to implement the relativistic notion of causality in any field theory and to define a notion of time dimension. We propose that at the microscopic level the metric is Riemannian and that the Lorentzian structure, usually thought as fundamental, is in fact an effective property, that emerges in some regions of a 4-dimensional space with a positive definite metric. We argue that a decent classical field theory for scalars, vectors and spinors in flat spacetime can be constructed, and that gravity can be included under the form of a covariant Galileon th

APA, Harvard, Vancouver, ISO, and other styles

41

Guendelman, Eduardo, Emil Nissimov, and Svetlana Pacheva. "Vacuum structure and gravitational bags produced by metric-independent space–time volume-form dynamics." International Journal of Modern Physics A 30, no. 22 (2015): 1550133. http://dx.doi.org/10.1142/s0217751x1550133x.

Full text

Abstract:

We propose a new class of gravity-matter theories, describing [Formula: see text] gravity interacting with a nonstandard nonlinear gauge field system and a scalar “dilaton,” formulated in terms of two different non-Riemannian volume-forms (generally covariant integration measure densities) on the underlying space–time manifold, which are independent of the Riemannian metric. The nonlinear gauge field system contains a square-root [Formula: see text] of the standard Maxwell Lagrangian which is known to describe charge confinement in flat space–time. The initial new gravity-matter model is invar

APA, Harvard, Vancouver, ISO, and other styles

42

Fernández Cristóbal, José Ma. "Weyl invariance in metric f(R) gravity." Revista Mexicana de Física 64, no. 2 (2018): 181. http://dx.doi.org/10.31349/revmexfis.64.181.

Full text

Abstract:

We aim to derive the most general f(R) gravity theory, including thematter, so that it be Weyl invariant. Making use of the mathematicalequivalence of these theories with an type of scalar-tensor theory, and byimposing the Weyl invariance for the pure gravity as well as for the mattersector, we obtain the fundamental equation that restricts the form of V (phi) (and, accordingly, of f(R)) so that the resulting action to be Weylinvariant in the Jordan frame. We show that this action is not otherthan the so-called dilaton gravity action with one scalar eld,, whicheective mass is R and Phi depende

APA, Harvard, Vancouver, ISO, and other styles

43

Alibert, Y. "New metric to quantify the similarity between planetary systems: application to dimensionality reduction using T-SNE." Astronomy & Astrophysics 624 (April 2019): A45. http://dx.doi.org/10.1051/0004-6361/201834592.

Full text

Abstract:

Context. Planet formation models now often consider the formation of planetary systems with more than one planet per system. This raises the question of how to represent planetary systems in a convenient way (e.g. for visualisation purpose) and how to define the similarity between two planetary systems, for example to compare models and observations. Aims. We define a new metric to infer the similarity between two planetary systems, based on the properties of planets that belong to these systems. We then compare the similarity of planetary systems with the similarity of protoplanetary discs in

APA, Harvard, Vancouver, ISO, and other styles

44

Zhu, Hongmei. "Finsler warped product metrics with almost vanishing H-curvature." International Journal of Geometric Methods in Modern Physics 17, no. 12 (2020): 2050188. http://dx.doi.org/10.1142/s0219887820501881.

Full text

Abstract:

In this paper, we show that a Finsler warped product metric is of almost vanishing [Formula: see text]-curvature if and only if it is of almost vanishing [Formula: see text]-curvature. Furthermore, the corresponding one form is exact.

APA, Harvard, Vancouver, ISO, and other styles

45

SHIMIZU, T., and K. WATANABE. "A RELATIVISTIC DESCRIPTION OF GENTRY'S NEW REDSHIFT INTERPRETATION." Modern Physics Letters A 14, no. 12 (1999): 779–90. http://dx.doi.org/10.1142/s0217732399000821.

Full text

Abstract:

We obtain a new expression of the Friedmann–Robertson–Walker metric, which is an analogue of a static chart of the de Sitter space–time. The reduced metric contains two functions, M(T, R) and Ψ(T, R), which are interpreted as, respectively, the mass function and the gravitational potential. We find that, near the coordinate origin, the reduced metric can be approximated in a static form and that the approximated metric function, Ψ(R) satisfies the Poisson equation. Moreover, when the model parameters of the Friedmann–Robertson–Walker metric are suitably chosen, the approximated metric coincide

APA, Harvard, Vancouver, ISO, and other styles

46

Bagaglini, Leonardo, Marisa Fernández, and Anna Fino. "Coclosed G2-structures inducing nilsolitons." Forum Mathematicum 30, no. 1 (2018): 109–28. http://dx.doi.org/10.1515/forum-2016-0238.

Full text

Abstract:

Abstract We show obstructions to the existence of a coclosed {\mathrm{G}_{2}} -structure on a Lie algebra {\mathfrak{g}} of dimension seven with non-trivial center. In particular, we prove that if there exists a Lie algebra epimorphism from {\mathfrak{g}} to a six-dimensional Lie algebra {\mathfrak{h}} , with the kernel contained in the center of {\mathfrak{g}} , then any coclosed {\mathrm{G}_{2}} -structure on {\mathfrak{g}} induces a closed and stable three form on {\mathfrak{h}} that defines an almost complex structure on {\mathfrak{h}} . As a consequence, we obtain a classification of the

APA, Harvard, Vancouver, ISO, and other styles

47

ROBERTS, M. D. "EXACT NONNULL WAVELIKE SOLUTIONS TO GRAVITY WITH QUADRATIC LAGRANGIANS." International Journal of Modern Physics A 09, no. 02 (1994): 167–79. http://dx.doi.org/10.1142/s0217751x9400008x.

Full text

Abstract:

Solutions to gravity with quadratic Lagrangians are found for the simple case where the only nonconstant metric component is the lapse N and the Riemann tensor takes the form [Formula: see text] thus these solutions depend on cross terms in the Riemann tensor and therefore complement linearized theory where it is the derivatives of the Riemann tensor that matter. The relationship of this metric to the null gravitational radiation metric of Peres is given. Gravitational energy Poynting vectors are constructed for the solutions and one of these, based on the Lanczos tensor, supports the indicati

APA, Harvard, Vancouver, ISO, and other styles

48

Hu, Jiaxin, and Guanhua Liu. "Upper estimates of heat kernels for non-local Dirichlet forms on doubling spaces." Forum Mathematicum 34, no. 1 (2022): 225–77. http://dx.doi.org/10.1515/forum-2021-0096.

Full text

Abstract:

Abstract In this paper, we present a new approach to obtaining the off-diagonal upper estimate of the heat kernel for any regular Dirichlet form without a killing part on the doubling space. One of the novelties is that we have obtained the weighted L 2 {L^{2}} -norm estimate of the survival function 1 - P t B ⁢ 1 B {1-P_{t}^{B}1_{B}} for any metric ball B, which yields a nice tail estimate of the heat semigroup associated with the Dirichlet form. The parabolic L 2 {L^{2}} mean-value inequality is borrowed to use.

APA, Harvard, Vancouver, ISO, and other styles

49

Bahram, Sadeghi Bigham Raheleh Abyar Langroudi. "Measuring similarity for query in geometric data." SN Applied Sciences 1, no. 10 (2019): 1193. https://doi.org/10.5281/zenodo.3783814.

Full text

Abstract:

One of the most important steps which is used in every data mining projects is searching an object or some similar objects in a data set. For geometric data, there are some methods that measure the difference between two objects. In recent years, researchers have focused on these types of metrics and used them in different applications (e.g., shape matching, machine vision, map generation, etc.). The query problem in these kinds of applications is more complicated when we have big data. In this paper, a new metric is presented which works efficiently when the geometric objects are in discrete

APA, Harvard, Vancouver, ISO, and other styles

50

Manev, Mancho. "Yamabe Solitons on Conformal Almost-Contact Complex Riemannian Manifolds with Vertical Torse-Forming Vector Field." Axioms 12, no. 1 (2023): 44. http://dx.doi.org/10.3390/axioms12010044.

Full text

Abstract:

A Yamabe soliton is considered on an almost-contact complex Riemannian manifold (also known as an almost-contact B-metric manifold), which is obtained by a contact conformal transformation of the Reeb vector field, its dual contact 1-form, the B-metric, and its associated B-metric. A case in which the potential is a torse-forming vector field of constant length on the vertical distribution determined by the Reeb vector field is studied. In this way, manifolds from one of the main classes of the studied manifolds are obtained. The same class contains the conformally equivalent manifolds of cosy

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!