Singularities of the Casimir Energy for Quantum Field Theories with Lifshitz Dimensions

We study the singularities that the Casimir energy of a scalar field in spacetimes with Lifshitz dimensions exhibits, and provide expressions of the energy in terms of multidimensional zeta functions for the massless case. Using the zeta-regularization method, we found that when the 4-dimensional spacetime has Lifshitz dimensions, then for specific values of the critical exponents, the Casimir energy is singular, in contrast to the non-Lifshitz case. Particularly we found that when the value of the critical exponent is $z=2$, the Casimir energy is singular, while for $z\geq 3$ the Casimir energy is regular. In addition, when flat extra dimensions are considered, the critical exponents of the Lifshitz dimensions affect drastically the Casimir energy, introducing singularities that are absent in the non-Lifshitz case. We also discuss the Casimir energy in the context of braneworld models and the perspective of Lifshitz dimensions in such framework.Comment: Major Revision, Similar to Journal Versio

Low Dimensional Supersymmetries in SUSY Chern-Simons Systems and Geometrical Implications

We study in detail the underlying graded geometric structure of abelian N=2 supersymmetric Chern-Simons theory in $(2+1)$-dimensions. This structure is an attribute of the hidden unbroken one dimensional N=2 supersymmetries that the system also possesses. We establish the result that the geometric structures corresponding to the bosonic and to the fermionic sectors are equivalent fibre bundles over the $(2+1)$-dimensional manifold. Moreover, we find a geometrical answer to the question why some and not all of the fermionic sections are related to a N=2 supersymmetric algebra. Our findings are useful for the quantum theory of Chern-Simons vortices.Comment: Revised Version. arXiv admin note: text overlap with arXiv:1308.046

Newton's Law Modifications due to a Sol Manifold Extra Dimensional Space

The corrections to the gravitational potential due to a Sol extra dimensional compact manifold, denoted as $M_A^3$, are studied. The total spacetime is $M^4\times M_A^3$. We compare the range of the corrections to the range of the $T^3$ corrections. It is found that for small values of the radius of the extra dimensions ($R<10^{-6}$) the the Sol manifold corrections are large compared to the 3-torus corrections. Also, Sol manifolds corrections can be larger, comparable or smaller compared to the 3-torus case, for larger $R$.Comment: Based on talk given in Recent Developments in Gravity, June 8-11, Ioannina, Greec

Localized Fermions on Domain Walls and Extended Supersymmetric Quantum Mechanics

We study fermionic fields localized on topologically unstable domain walls bounded by strings in a grand unified theory theoretical framework. Particularly, we found that the localized fermionic degrees of freedom, which are up and down quarks as long as charged leptons, are connected to three independent N=2, $d=1$ supersymmetric quantum mechanics algebras. As we demonstrate, these algebras can be combined to form higher order representations of N=2, $d=1$ supersymmetry. Due to the uniform coupling of the domain wall solutions to the down-quarks and leptons, we also show that a higher order N=2, $d=1$ representation of the down-quark--lepton system is invariant under a duality transformation between the couplings. In addition, the two N=2, $d=1$ supersymmetries of the down-quark--lepton system, combine at the coupling unification scale to an N=4, $d=1$ supersymmetry. Furthermore, we present the various extra geometric and algebraic attributes that the fermionic systems acquire, owing to the underlying N=2, $d=1$ algebras.Comment: Revised versio