Related papers: Lagrangian Identity and Mass Evolution of Particle…
We expand the relativistic open bosonic string in powers of $1/c^2$ where $c$ is the speed of light. We perform this expansion to next-to-leading order in $1/c^2$ and relate our results to known descriptions of non-relativistic open strings…
We present a cosmological model in 1+m+p dimensions, where in m-dimensional space there are uniformly distributed p-branes wrapping over the extra p-dimensions. We find that during cosmological evolution m-dimensional space expands with the…
The Quadratic Gravitational Lagrangian with torsion provides us with a richer number of solutions than the Einstein-Hilbert Lagrangian does. With proper interpretation, these solutions, together, seem to give good explanations of the form…
We present a class of dynamical solutions in a D-dimensional gravitational theory coupled to a dilaton, a form field strength, and a cosmological constant. We find that for any D due to the presence of a cosmological constant, the metric of…
We study the space-time geometry generated by coupling a free scalar field with a non-canonical kinetic term to General Relativity in $(2+1)$ dimensions. After identifying a family of scalar Lagrangians that yield exact analytical solutions…
We study the dynamics of an open membrane with a cylindrical topology, in the background of a constant three form, whose boundary is attached to p-branes. The boundary closed string is coupled to a two form potential to ensure gauge…
We present a comparative analysis of several methods, known as local Lagrangian approximations, which are aimed to the description of the nonlinear evolution of large-scale structure. We have investigated various aspects of these…
We study the effect of the Dp-brane gas in string cosmology. When one kind of Dp-brane gas dominates, we find that the cosmology is equivalent to that of the Brans-Dicke theory with the perfect fluid type matter. We obtain $\gamma$, the…
We assume that a self-gravitating string is locally described by a thin tube of matter represented by a ``smoothed conical metric''. If we impose a specific constraint on the model of string then its central line obeys the Nambu-Goto…
We classify effective actions for Nambu-Goldstone (NG) bosons assuming absence of anomalies. Special attention is paid to Lagrangians invariant only up to a surface term, shown to be in a one-to-one correspondence with Chern-Simons (CS)…
In 2021, Lei et al. claimed the equivalence between the two Lagrangians $\mathcal{L}_1 =-mc\sqrt{-g_{\mu\nu}{\dot{x}}^\mu{\dot{x}}^\nu}-V$ and $\mathcal{L}_2 = \frac{1}{2}mg_{\mu\nu} {\dot{x}}^\mu{\dot{x}}^\nu-V$ for describing particle…
A non-topological Lorentz gauge model of gravity with torsion based on Gauss-Bonnet type Lagrangian is considered. The Lagrangian differs from the Lovelock term in four-dimensional space-time and has a number of interesting features. We…
The classical linearised gravitational self interaction of a Goto-Nambu string is examined in four spacetime dimensions. Using a conveniently gauge independent tensorial treatment, the divergent part of the self-force is shown to be exactly…
String compactifications with non-abelian gauge fields localized on D-branes, with background NSNS and RR 3-form fluxes, and with non-trivial warp factors, can naturally exist within T-dual versions of type I string theory. We develop a…
In this work, we study Lagrangian formulations for self-dual gauge theories, also known as chiral $n$-form gauge theories, for $n = 2p$ in $D = 4p+2$ dimensional spacetime. Motivated by a recent formulation of M5-branes derived from the BLG…
We generalize to dimension $p>1$ the notion of string structure and discuss the related obstruction. We apply our results to a model of bosonic $p$-branes propagating on a principal $G$-bundle, coupled to a Yang--Mills field and an…
In this paper we consider a model based on interacting $p-$forms and explore some cosmological applications. Restricting to gauge invariant actions, we build a general Lagrangian allowing for arbitrary interactions between the $p-$forms…
We describe the construction of new configurations of self-gravitating p-branes with worldvolume geometries of the form R^{1,p-s} x S^s, with 1\leq s\leq p, ie, tubular branes. Since such branes are typically unstable against collapse of…
A Newtonian-like theory inspired by the Brans-Dicke gravitational Lagrangian has been recently proposed in Ref. arXiv:2009.04434(v4). We propose here a new variant of this theory such that the usual Newtonian second law is preserved. The…
We study the time evolution of entanglement entropy in expanding universes with various matters. To describe expanding universes holographically, we take into account a braneworld moving in an asymptotic AdS space involving a uniform…