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In this paper, the model of radial motion of dusty matter for the spherically symmetric case in General Relativity (GR) was developed. The model can be used, in particular, to describe galactic halos of dark matter. The ...

ABSTRACT Tensism is the view that tense is not merely a property of language and the mind (narrowly individuated), but of the world itself. Perspectivalism extends this idea to all perspectival properties be they person ...

We propose an extended General Relativistic formalism with boundary terms included, that describes the dynamics of quantum spinor fields, which can take intermediate values, named (3 + 1) -anyons. In the approach here wo...

We calculate the algebra of constraints for deparametrized general relativity with a space-time filling unstable D-brane for an arbitrary value of tachyon field T. We also propose observables that have vanishing Poisson ...

Abstract Physiological interpretations of Systems Biology have made many advances since the Principles of Systems Biology were first published in this journal in 2008. Those advances show that the main principle, Biologi...

In this work, shells are mathematically constructed by applying the cut and paste procedure to D-dimensional spherically symmetric geometries. The weak energy condition for the matter on the shells is briefly analyzed. T...

We study circular shells in a (2+1)-dimensional background within the framework of Einstein-Born-Infeld theory. For shells around black holes we analyze the mechanical stability under perturbations preserving the symmetr...

We investigate whether a dynamical wormhole could survive in a universe that undergoes a cosmological bounce. First, the conditions under which a wormhole could persist from a contracting to an expanding phase of the cos...

Experiments on the relative merits and demerits of slotted wingtips mimicking a bird’s primary feathers have been performed. The real emargination length of feather tips, their flexibility and curved shapes during crui...

This paper is an attempt to summarize the effect of wing tip devices employed by birds, as well as aeronautical engineers in the past to improve the performance characteristics of aircraft. The focus is on reduction of t...

I argue for a four dimensional, non-dynamical view of space-time, where becoming is not an intrinsic property of reality. This view has many features in common with the Parmenidean conception of the universe. I discuss s...

The method of topological renormalization in anti–de Sitter (AdS) gravity consists in adding to the action a topological term which renders it finite, defining at the same time a well-posed variational problem. Here, w...

Foram avaliados os principais índices diastólicos, inclusive a velocidade de propagação mitral (Vp), em 36 cães sadios da raça Boxer, 18 de cada sexo, de idade entre um ano e meio e seis anos. A relação raiz aór...

Abstract We investigate the cosmological implications of an extended gravitational framework based on biconnection gravity, constructed from the Schr $$\ddot{\textrm{o}}$$ o ¨ dinger connection and its dual. In this app...

The present paper aims at testing a model to predict personal involvement with a social object which was inspired by the social psychological triangle proposed by Moscovici. The triangle bridges three essential aspects o...

We report the formation of a soliton—termed “event soliton”—in nonlinear photonic spacetime crystals (STCs). In these media, simultaneous spatiotemporal periodic modulation of the dielectric constant generates mi...

Lensing of gravitational waves (GWs) due to intervening massive astrophysical systems between the source and the observer is an inevitable consequence of the general theory of relativity, which can produce multiple GW ev...

Abstract The exploration of the surrounding world and the universe is an important theme in the legacy of humankind. The detection of gravitational waves is adding a new dimension to this grand effort. What are the funda...

We reassess the capacity for multimessenger inference of AT2017gfo/GW170817 using both kilonova and gravitational wave emission within the context of a recent simulation-based surrogate model for kilonova emission. Indep...

The secular approximation of the hierarchical three body systems has been proven to be very useful in addressing many astrophysical systems, from planets to stars to black holes. In such a system, two objects are on a ti...

This book is based on the lecture notes of the course on black hole astrophysicsgiven at the University of La Plata, Argentina, by one of us (GER). The materialaims at advanced undergraduate and graduate students with in...

The study of the structure of compact objects in modified theories of gravity can be useful to constrain f(R)-theories in the strong gravitational regime. In particular, the structure of compact stars inthe theory with L...