Skyrmions from a Born-Infeld action

Abstract

We consider a geometrically motivated Skyrme model based on a general covariant kinetic term proposed originally by Born and Infeld. We introduce this new term by generalizing the Born-Infeld action to a non-abelian SU (2) gauge theory and by using the hidden gauge symmetry formalism. The static properties of the Skyrmion are then analyzed and compared with other Skyrme-like models.

New regular black hole solution from nonlinear electrodynamics

“…Because of the structure of the metric components of our solution (13) and their derivatives, the components of the Riemman tensor behave generically at r = 0 as ∼ g(r)/r a , where g(r) is a function vanishing exponentially as r → 0. This fact explain the bounded behavior of the invariants (15)- (17). Moreover, the quoted behavior at r = 0 extends to the covariant differential of any order of the Riemman tensor (the derivative of an exponentially vanishing function is again an exponentially vanishing function, and the contributions due to the Christoffel symbols entering in the covariant derivatives do not alter the quoted pattern).…”

“…one concludes they are all regular everywhere. Hence, for s≤s c the singularities appearing in (13) due to the vanishing of A are only coordinate-singularities describing the existence of event horizons, consequently, we are in the presence of black hole solutions for |q| ≤ 2s c m ≈ 1.05 m. It should be notice that metrics possessing regular standard invariants, as (15)- (17), could still present non-regular behavior of the differential invariants, R ;α1···αn R ;α1···αn , R µν;α1···αn R µν;α1···αn , R µναβ;α1···αn R µναβ;α1···αn [42]. Because of the structure of the metric components of our solution (13) and their derivatives, the components of the Riemman tensor behave generically at r = 0 as ∼ g(r)/r a , where g(r) is a function vanishing exponentially as r → 0.…”

Chiral Dirac–Born–Infeld solitons with SDiff symmetry

“…For some generalizations see [10,11]. However, on the contrary to the standard skyrmions, little is known about DBI chiral solitons.…”

Multilayer solutions for Near-BPS Skyrme Models

“…In its original form, it reproduces most of the properties of the nucleon within a 30% accuracy which is considered a rather good agreement for a model involving only two free parameters. Modifications in the structure of the potential term, the contribution of other vector mesons or simply the addition of higher-order terms in derivatives of the pion fields [2,3,4] may help to improve some of the features of the model but in general these models fail to give an appropriate account of multibaryon physics or nuclei. Among the most common problems are large binding energies, shell-like baryon density configurations with unexpected discrete symmetries, as well as a nuclear radius that grows as √ A instead of the usual |A| 1/3 mass number dependence.…”