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16
Fourdimensional String Compactifications with DBranes, Orientifolds and Fluxes
"... This review article provides a pedagogical introduction into various classes of chiral string compactifications to four dimensions with Dbranes and fluxes. The main concern is to provide all necessary technical tools to explicitly construct fourdimensional orientifold vacua, with the final aim to ..."
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Cited by 149 (15 self)
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This review article provides a pedagogical introduction into various classes of chiral string compactifications to four dimensions with Dbranes and fluxes. The main concern is to provide all necessary technical tools to explicitly construct fourdimensional orientifold vacua, with the final aim to come as close as possible to the supersymmetric Standard Model. Furthermore, we outline the available methods to derive the resulting fourdimensional effective action. Finally, we summarize recent attempts to address the
Fixing all moduli in a simple Ftheory compactification,” [arXiv:hepth/0503124
"... We discuss a simple example of an Ftheory compactification on a CalabiYau fourfold where background fluxes, nonperturbative effects from Euclidean D3 instantons and gauge dynamics on D7 branes allow us to fix all closed and open string moduli. We explicitly check that the known higher order correc ..."
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Cited by 91 (8 self)
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We discuss a simple example of an Ftheory compactification on a CalabiYau fourfold where background fluxes, nonperturbative effects from Euclidean D3 instantons and gauge dynamics on D7 branes allow us to fix all closed and open string moduli. We explicitly check that the known higher order corrections to the potential, which we neglect in our leading approximation, only shift the results by a small amount. In our exploration of the model, we encounter interesting new phenomena, including examples of transitions where D7 branes absorb O3 planes, while changing topology to preserve the net D3 charge.
Discrete torsion orbifolds and Dbranes
 II, J. High Energy Phys
"... Dbranes on orbifolds with and without discrete torsion are analysed in a unified way using the boundary state formalism. For the example of the Z2 × Z2 orbifold it is found that both the theory with and without discrete torsion possess Dbranes whose worldvolume carries conventional and projective ..."
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Cited by 25 (4 self)
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Dbranes on orbifolds with and without discrete torsion are analysed in a unified way using the boundary state formalism. For the example of the Z2 × Z2 orbifold it is found that both the theory with and without discrete torsion possess Dbranes whose worldvolume carries conventional and projective representations of the orbifold group. The resulting Dbrane spectrum is shown to be consistent with Tduality.
Notes on Orientifolds of Rational Conformal Field Theories
, 2002
"... We review and develop the construction of crosscap states associated with parity symmetries in rational conformal field theories. A general method to construct crosscap states in abelian orbifold models is presented. It is then applied to rational U(1) and parafermion systems, where in addition we s ..."
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Cited by 22 (2 self)
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We review and develop the construction of crosscap states associated with parity symmetries in rational conformal field theories. A general method to construct crosscap states in abelian orbifold models is presented. It is then applied to rational U(1) and parafermion systems, where in addition we study the geometrical interpretation of the corresponding parities.
Discrete Torsion, Covering Groups and Quiver Diagrams
, 2001
"... Preprint typeset in JHEP style. HYPER VERSION ..."
D = 4, N = 1 orientifolds with vector structure” Nucl. Phys. B596
, 2001
"... hepth/0007087 ..."
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Dbranes in nonabelian orbifolds with discrete torsion
, 2001
"... hepth/0109170 ..."
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Discrete torsion orbifolds and Dbranes. ii,” hepth/0101143
"... The consistency of the orbifold action on open strings between Dbranes in orbifold theories with and without discrete torsion is analysed carefully. For the example of the C 3 / Z2 × Z2 theory, it is found that the consistency of the orbifold action requires that the Dbrane spectrum contains brane ..."
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Cited by 1 (0 self)
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The consistency of the orbifold action on open strings between Dbranes in orbifold theories with and without discrete torsion is analysed carefully. For the example of the C 3 / Z2 × Z2 theory, it is found that the consistency of the orbifold action requires that the Dbrane spectrum contains branes that give rise to a conventional representation of the orbifold group as well as branes for which the representation is projective. It is also shown how the results generalise to the orbifolds C 3 / ZN × ZN, for which a number of novel features arise. In particular, the N> 2 theories with minimal discrete torsion have nonBPS branes charged under twisted RR potentials that couple to none of the (known) BPS branes.
Strings, Branes and Extra Dimensions
, 2002
"... This review is devoted to strings and branes. Firstly, perturbative string theory is introduced. The appearance of various types of branes is discussed. These include orbifold fixed planes, Dbranes and orientifold planes. The connection to BPS vacua of supergravity is presented afterwards. As appli ..."
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This review is devoted to strings and branes. Firstly, perturbative string theory is introduced. The appearance of various types of branes is discussed. These include orbifold fixed planes, Dbranes and orientifold planes. The connection to BPS vacua of supergravity is presented afterwards. As applications, we outline the role of branes in string dualities, field theory dualities, the AdS/CFT correspondence and scenarios where the string scale is at a TeV. Some issues of warped compactifications are also addressed. These comprise corrections to gravitational interactions as well as the cosmological constant problem. Contents
hepth/0206158
, 2002
"... Recently it has been shown that Dbranes in orientifolds are not always described by equivariant Real K–theory. In this paper we define a previously unstudied twisted version of equivariant Real K–theory which gives the Dbrane spectrum for such orientifolds. We find that equivariant Real K–theory c ..."
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Recently it has been shown that Dbranes in orientifolds are not always described by equivariant Real K–theory. In this paper we define a previously unstudied twisted version of equivariant Real K–theory which gives the Dbrane spectrum for such orientifolds. We find that equivariant Real K–theory can be twisted by elements of a generalised group cohomology. This cohomology classifies all orientifolds just as group cohomology classifies all orbifolds. As an example we consider the Ω × I4 orientifolds. We completely determine the equivariant orthogonal K–theory KOZZ2 (Rp,q) and analyse the twisted versions. Agreement is found between K–theory and Boundary Confromal Field Theory (BCFT) results for both integrally and torsioncharged Dbranes.