A. A. Usmani ∗ and Z. Hasan ∗ Department of Physics, Aligarh Muslim University, Aligarh 202 002, Uttar Pradesh, India. F. Rahaman † and Sk. A. Rakib † Department of Mathematics, Jadavpur University, Kolkata 700 032, West Bengal, India Saibal Ray ‡ Department of Physics, Government College of Engineering & Ceramic Technology, Kolkata 700 010, West Bengal, India Peter K. F. Kuhfittig § Department of Mathematics, Milwaukee School of Engineering, Milwaukee, Wisconsin 53202-3109, USA (Dated: November 12, 2018) Thin-shell wormholes from charged black holes in generalized dilaton-axion gravity arXiv:1001.1415v2 [gr-qc] 5 Jun 2010 $^{∗}$Electronic address: anisul@iucaa.ernet.in $^{†}$Electronic address: farook rahaman@yahoo.com $^{‡}$Electronic address: saibal@iucaa.ernet.in $^{§}$Electronic address: kuhfitti@msoe.edu This paper discusses a new type of thin-shell wormhole constructed by applying the cut-and-paste technique to two copies of a charged black hole in generalized dilaton-axion gravity, which was inspired by low-energy string theory. After analyzing various aspects of this thin-shell wormhole, we discuss its stability to linearized spherically symmetric perturbations. κ = 8 πG , R is the curvature scalar, F$_{µν}$ is the Maxwell field tensor, while ϕ and ζ are two massless scalar or pseudo scalar fields, which are coupled to the Maxwell field. This coupling is described by the functions α and β . Here ζ acquires a non-minimal kinetic term ω . In the context of low-energy string theory, fields φ and ξ can be identified as massless scalar dilaton and pseudo scalar axion fields, respectively. With the above action, Eq. (1), Sur, et al. , [21] found the most general class of black-hole solutions and ob- tained two types of metrics, classified as asymptotically flat and asymptotically non-flat. Since we are interested in obtaining a thin-shell wormhole from this new black hole, we adopt the asymptotically flat metric given by where and where, according to Ref. [21], the exponent n is a dimen- sionless constant stricly greater than 0 and stricly less More recently, Sur, Das, and SenGupta [21] discovered a new black-hole solution for Einstein-Maxwell scalar field systems inspired by low-energy string theory. They considered a generalized action in which two scalar fields are minimally coupled to an Einstein-Hilbert-Maxwell The study of traversable wormholes has received con- siderable attention from researchers for the past two decades. Although lacking observational evidence, worm- holes are just as good a prediction of the general the- ory of relativity as black holes. In particular, we re- fer to the pioneering work of Visser [1], who proposed a theoretical method for constructing a new class of traversable Lorentzian wormholes from black-hole space- times. This construction proceeds by surgically graft- ing two Schwarzschild spacetimes together in such a way that no event horizon is permitted to form. The resulting structure is a wormhole spacetime in which the throat is a three-dimensional thin shell. In recent years, Visser’s approach was adopted by various authors for construct- ing thin-shell wormholes by similar methods, generally requiring spherical symmetry [2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]. The approach is of special interest because it minimizes the amount of ex- otic matter required. All the exotic matter is confined to the shell. field in four dimensions, where PACS numbers: 95.30.Sf, 95.36.+x, 04.20.Jb I. INTRODUCTION I = 1 2 κ ∫ d 4 $_{x}$√ − g [ R − 1 2 ∂$_{µ}$ϕ∂ $^{µ}$ϕ − W ] , (1) W = 1 2 ω ( ϕ ) ∂$_{µ}$ζ∂ $^{µ}$ζ − α ( ϕ, ζ ) F$_{µν}$ F µν − β ( ϕ, ζ ) F$_{µν}$ F µν $^{∗}$, ds 2 = − f ( r ) dt $^{2}$+ f ( r ) − $^{1}$dr$^{2}$+ h ( r )( dθ $^{2}$+sin 2 θdφ $^{2}$) , (2) f ( r ) = ( r − r$_{−}$ )( r − r$_{+}$ ) ( r − r$_{0}$ ) 2 − 2 $^{n}$( r + r$_{0}$ ) 2 $_{n}$, (3) h ( r ) = ( r + r$_{0}$ ) 2 n ( r − r$_{0}$ ) 2 n − $_{2}$, (4) APS/1: Thin-shell-wormhole