Black holes with topological charges in Chern-Simons AdS5 supergravity

We study static black hole solutions with locally spherical horizons coupled to non-Abelian field in $$ \mathcal{N} $$ N = 4 Chern-Simons AdS5 supergravity. They are governed by three parameters associated to the mass, axial torsion and amplitude of the internal soliton, and two ones to the gravitational hair. They describe geometries that can be a global AdS space, naked singularity or a (non-)extremal black hole. We analyze physical properties of two inequivalent asymptotically AdS solutions when the spatial section at radial infinity is either a 3-sphere or a projective 3-space. An important feature of these 3-parametric solutions is that they possess a topological structure including two SU(2) solitons that wind nontrivially around the black hole horizon, as characterized by the Pontryagin index. In the extremal black hole limit, the solitons’ strengths match and a soliton-antisoliton system unwinds. That limit admits both non-BPS and BPS configurations. For the latter, the pure gauge and non-pure gauge solutions preserve 1/2 and 1/16 of the original supersymmetries, respectively. In a general case, we compute conserved charges in Hamiltonian formalism, finding many similarities with standard supergravity black holes.

CALCULATION SCHEME OF REINFORCED CONCRETE STRUCTURES OF CIRCULAR CROSS-SECTION UNDER BENDING WITH TORSION

The developed design diagram of the ultimate resistance of reinforced concrete structures in bending with torsion of circular cross-sections most fully reflects the features of their actual exploitation. For a spatial crack of a diagonal large ellipse, sections are taken in the form of a swirling propeller with concave and convex spatial parabolas from the first and second blocks between vertical transverse circular sections from the beginning to the end of the crack. For practical calculations in compressed and tensioned concrete, a polyline section of three sections is considered: two longitudinal trapezoids and the third middle section of the radius curve of a small ellipse close to forty-five degrees. When calculating unknown forces, solutions of the equations of equilibrium and deformations of the sections are made up to the end of the crack passing through the moment points for the resultant moments and the projections of internal and external forces. Shear torsional stresses along the linear longitudinal sections of the trapezoid were presented, as well as normal and shear stresses located on the end cross-sections at a distance x from the support. The height of the compressed area of concrete decreases with an increase in bending moments in the spatial section between the first and third cross-sections. It is found in their relationships and connections. The dowel action of reinforcement is determined using a special model of the second level with discrete constants. The static loading scheme was considered from the standpoint of an additional proportional relationship between the torques along the length of the bar in the spatial section and the first and third transverse sections. For a dangerous spatial crack, when projected onto the horizontal axis, the length C was found from a diagonal large ellipse of a round bar.

CALCULATION MODEL OF A COMPLEX-STRESSED REINFORCED CONCRETE ELEMENT UNDER TORSION WITH BENDING

The article presents the methodology and principles of creating calculation models for reinforced concrete structures operating in conditions of complex resistance. A block calculation model of reinforced concrete bar structures in torsion with bending is presented. This model consists of a support block formed by a spatial crack and a compressed zone of concrete closed on it and a second block formed by a vertical section running perpendicular to the longitudinal axis of a reinforced concrete element along the edge of the compressed zone closing the spatial spiral. Cases are considered when the torque effec has the greatest influenceon the stress-strain state of structures. In this case, the following forces are taken into account as the calculated forces in the spatial section: normal and tangential forces in the concrete of the compressed zone; components of axial and shear forces in the reinforcement crossed by a spatial crack. A feature of the proposed calculation model is that it considers independently of each other the strength of an element in spatial sections passing along a spatial crack, and the strength of an element between spatial cracks. The spatial section is formed by a crack located on three sides of the element and a compressed zone located on the fourth side and closing the ends of the spiral crack. In this case, the compressed zone, depending on the ratio of the bending and torque moments, can be located along the horizontal and vertical (lateral) edges of the element. The governing equations are written in the form of static equations for the adopted calculation cross-sections and a closed-loop system that unites them, written as a function of many variables with Lagrange multipliers λi. On the basis of the constructed function for all the variables included in it, an additional non-decaying system of equations has been compiled, from which follows a dependence that allows finding the projecton of a dangerous spatial crack.

Islands in de Sitter space

We consider black holes in 2d de Sitter JT gravity coupled to a CFT, and entangled with matter in a disjoint non-gravitating universe. Tracing out the entangling matter leaves the CFT in a density matrix whose stress tensor backreacts on the de Sitter geometry, lengthening the wormhole behind the black hole horizon. Naively, the entropy of the entangling matter increases without bound as the strength of the entanglement increases, but the monogamy property predicts that this growth must level off. We compute the entropy via the replica trick, including wormholes between the replica copies of the de Sitter geometry, and find a competition between conventional field theory entanglement entropy and the surface area of extremal “islands” in the de Sitter geometry. The black hole and cosmological horizons both play a role in generating such islands in the backreacted geometry, and have the effect of stabilizing the entropy growth as required by monogamy. We first show this in a scenario in which the de Sitter spatial section has been decompactified to an interval. Then we consider the compact geometry, and argue for a novel interpretation of the island formula in the context of closed universes that recovers the Page curve. Finally, we comment on the application of our construction to the cosmological horizon in empty de Sitter space.

Final fate of Kantowski–Sachs gravitational collapse

Although it is not a fundamental question, determining exact and general solutions for a given theory has advantages over a numerical integration in many specific cases. Of course, respecting the peculiarities of the problem. Revisiting the integration of the General Relativity Theory field equations for the Kantowski–Sachs spacetime describes a homogeneous but anisotropic universe whose spatial section has the topology of [Formula: see text], we integrate the equations for arbitrary curvature parameter and write the solutions considering the process of gravitational collapse. We took the opportunity and made some comments involving some features of the model such as energy density, shear, viscosity and the production of gravitational waves via Petrov classification.

IMPROVEMENT OF DISCHARGE SECTION LINE MEASUREMENT PROGRAM

The article considers methods of misalignment determination of constructions and equipment, and analyses methods based on the spatial section line location. It is noted that in certain conditions the use of total stations and GNSS-receivers allows to perform a section line the measurements with necessary accuracy. To carry out measurements on the overall discharge section line program the improved method is suggested. The advantage of the suggested method is that if there is no opportunity for compulsory centering of a total station on the survey control points of the section line, it suggests using an extra survey control point of dam site to increase the measurement accuracy. The extra survey control point is settled in the site with high accuracy with the help of centering device. The measurements were performed by the suggested method and the results were analyzed. It was stated that the considered method increases the accuracy of misalignment determination of the control points on the overall discharge section line program.

CALCULATED MODELS OF DEFORMATION OF REINFORCED CONCRETE STRUCTURES IN BUILDINGS AND STRUCTURES DURING BENDING

A computational model of the complex resistance of reinforced concrete structures in buildings and structures under torsion with bending is proposed, consisting of a support block (formed by a spatial crack and a compressed concrete zone closed on it, - spatial section k) and a second block formed by a vertical section I– I, passing perpendicular to the longitudinal axis of the reinforced concrete element along the edge of the compressed zone, closing the spatial spiral-shaped crack. Cases are considered when the torque effect has the greatest influence on the stress-strain state of structures. We have a design diagram A of the resistance of a reinforced concrete structure under the combined action of a bending moment, torque and shear force for a spiral-shaped spatial crack, as well as a design diagram B for a spatial X-shaped crack. In this case, as the design forces in the spatial section, the following are taken into account: normal and tangential forces in the concrete of the compressed zone; components of axial and thrust forces in the working reinforcement crossed by a spatial crack. Resolving equations are constructed that form a closed-loop system and the Lagrange function that unites them is written. Using the partial derivatives of the constructed function with respect to all the variables included in it and equating them to zero, an additional system of equations is compiled, from which, after the appropriate algebraic transformations, a dependence is obtained that allows one to find the projection of a dangerous spatial crack.

THE SECOND STAGE OF STRESSED-DEFORMED CONDITION OF REINFORCED CONCRETE STRUCTURES WHEN TURNING WITH BENDING (CASE 2)

It is proposed a complex resistance computational model of reinforced concrete constructions in build­ings and structures under the action torsion with bending. It consists of from the block near the support (formed by a spatial crack and a compressed concrete zone closed by it - a spatial section k) and a second block, which is formed by a vertical cross section I-I passing perpendicularly to the longitudinal axis of the reinforced concrete element along the edge of the compressed zone, which closes the spatial spiral-shaped crack. The case when the greatest influence on the stress-strain state of structures has the effect of torque is considered (case 2). In this case, as the calculated forces are taken into account in the spatial section: normal and tangential forces in the concrete of the compressed zone; components of axial and “dowel” efforts in the working reinforcement, inter­sected by a spiral spatial crack. The resolving equations are constructed that form a closed system and the La­grange function is unified. Using the partial derivatives of the constructed function with respect to all the varia­bles entering into it and equating them to zero, an additional system of equations is constructed. The dependence is obtained after the corresponding algebraic transformations, that allows us to search for the projection of a dan­gerous spatial crack.

A note on quantum fields in conformally flat spacetimes

We develop a technique relating scalar fields with different masses in different conformally flat spacetimes. We apply this technique to the case of FRW spacetimes, with [Formula: see text], and discuss several examples. We also study various energy conditions and discuss how they constrain the spacetimes related by this technique. We calculate the two-point scalar correlator in the radiation-dominated universe with a hyperbolic spatial section from the one in the Milne universe using the above mapping. Finally, we consider trace anomaly and renormalized stress tensor for conformally flat spacetimes, especially Milne and radiation-dominated universe (with [Formula: see text]) using the transformation.

PENGAWASAN DINAS PEKERJAAN UMUM DAN PENATAAN RUANG DALAM ALIH FUNGSI LAHAN DI KECAMATAN CIMAHI UTARA KOTA CIMAHI

This research is entitled � The Supervision Of Public Works and Spatial Planning In Over The Conversion Land In North Cimahi Subdistrict Of Cimahi City�. The limitations problem in this study is not yet optimal controlling by Publick Works Control and Spatial Planning in the North Bandung Area. Then the research can be detail by identification the problem as follow : How the controlling of Public Works and Spatial Planning of Cimahi City areas in maintainance the availability of land that conversion does not occur continuously in? The method used in this reseach by using descriptive method of analysis with qualitative approach. While the technique on data collection is done through, literature study, interview, observation and by studying the local regulation, and performed data analysis techniques with three stages of data reduction, data presentation and conclusion. The interview was conducted in this reseach to Head of the Spatial Use Control Section, Head of North Cimahi Subdistrict and Staff of Permissions The Spatial Section. While the main instrument in this reseach is the researcher themselves. Based on the result of the research is population growth became one of the facts of conversion land, controls conducted by Department of Public Works and Spatial Planning has not been optimal because it has not been able to act witch regulations and commitment to built in to implement local regulations with the spatial fungction which resulted in land conversion occurred in The Area of North Bandung; North Cimahi Subdistrict; Cimahi City.