Finite Energy Solutions in Three-Dimensional Heterotic String Theory (1997)
We show that a large class of supersymmetric solutions to the low-energy effective field theory of heterotic string theory compactified on a seven torus can have finite energy, which we compute. The...
Supersymmetric Solutions in Three-Dimensional Heterotic String Theory (1997)
Bakas, Ioannis, Bourdeau, M, Lópes-Cardoso, G
We consider the low-energy effective field theory of heterotic string theory compactified on a seven-torus, and we construct electrically charged as well as more general solitonic solutions. These...
Quantum N = 2 Supersymmetric Black Holes in the S-T Model (1997)
Behrndt, K, Lópes-Cardoso, G, Gaida, I
We consider axion-free quantum corrected black hole solutions in the context of the heterotic S-T model with half the N=2, D=4 supersymmetries unbroken. We express the perturbatively corrected...
Perturbative gravitational couplings and Siegel modular forms in $D=4, N=2$ string models (1996)
We consider four-parameter $D=4,N=2$ string models with Hodge numbers $(4,214- 12n)$ and $(4,148)$, and we express their perturbative Wilsonian gravitational coupling $F_1$ in terms of Siegel modular...
Perturbative gravitational couplings and Siegel modular forms in $D=4, N=2$ string models (1996)
We consider four-parameter $D=4,N=2$ string models with Hodge numbers $(4,214- 12n)$ and $(4,148)$, and we express their perturbative Wilsonian gravitational coupling $F_1$ in terms of Siegel modular...
Classical and quantum N=2 supersymmetric black holes (1996)
Behrndt, K, Lópes-Cardoso, G, De Wit, Bernard, Kallosh, Renata E, Lüst, Dieter, Mohaupt, T
We use heterotic/type-II prepotentials to study quantum/classical black holes with half the $N=2, D=4$ supersymmetries unbroken. We show that, in the case of heterotic string compactifications, the...
On the Duality between the Heterotic String and F-Theory in 8 Dimensions (1996)
Lópes-Cardoso, G, Curio, G, Lüst, Dieter, Mohaupt, T
In this note we compare the moduli spaces of the heterotic string compactified on a two-torus and F-Theory compactified on an elliptic K3 surface for the case of an unbroken E8 x E8 gauge group. The...
Perturbative Couplings and Modular Forms in N=2 String Models with a Wilson Line (1996)
Lópes-Cardoso, G, Curio, G, Lüst, Dieter
We consider a class of four parameter D=4, N=2 string models, namely heterotic strings compactified on K3 times T2 together with their dual type II partners on Calabi-Yau three-folds. With the help...
Modular Symmetries of N=2 Black Holes (1996)
Lópes-Cardoso, G, Lüst, Dieter, Mohaupt, T
We discuss the transformation properties of classical extremal N=2 black hole solutions in S-T-U like models under S and T duality. Using invariants of (subgroups of) the triality group, which is the...
De Wit, Bernard, Lópes-Cardoso, G, Lüst, Dieter, Mohaupt, T, Rey, S J
The restrictions of target--space duality are imposed at the perturbative level on the holomorphic Wilsonian couplings that encode certain higher-order gravitational interactions in $N=2, D=4$...
Instanton numbers and exchange symmetries in N=2 dual string pairs (1996)
Lópes-Cardoso, G, Curio, G, Lüst, Dieter, Mohaupt, T
In this note, we comment on Calabi-Yau spaces with Hodge numbers h_{1, 1}=3 and h_{2,1}=243. We focus on the Calabi-Yau space WP_{1,1,2, 8, 12}(24) and show how some of its instanton numbers are...
Lópes-Cardoso, G, Curio, G, Lüst, Dieter, Mohaupt, T, Rey, S J
We study the BPS spectrum in D=4, N=4 heterotic string compactifications, with some emphasis on intermediate N=4 BPS states. These intermediate states, which can become short in N=2...
Perturbative and non-perturbative results for N=2 heterotic strings (1995)
Lópes-Cardoso, G, Mohaupt, T, Lüst, Dieter
In this paper we summarize our recent work about perturbative and non-perturbative effects in four-dimensional heterotic strings with N=2 space-time supersymmetry.
Perturbative and non-perturbative results for N=2 heterotic strings (1995)
Lópes-Cardoso, G, Lüst, Dieter, Mohaupt, T
In this paper we summarize our recent work about perturbative and non-perturbative effects in four-dimensional heterotic strings with N=2 space-time supersymmetry.
Natural supergravity inflation (1992)
We show that a single uncharged chiral superfield, canonically coupled to \mbox{$N=1$} supergravity with vanishing superpotential, naturally drives inflation in the early universe for a class of...