Mirror Maps and Instanton Sums for Complete Intersections in Weighted Projective Space

We consider a class of Calabi-Yau compactifications which are constructed as a complete intersection in weighted projective space. For manifolds with one K\"ahler modulus we construct the mirror manifolds and calculate the instanton sum.Comment: 10 page

Chern-Simons Gravity and Holographic Anomalies

We present a holographic treatment of Chern-Simons (CS) gravity theories in odd dimensions. We construct the associated holographic stress tensor and calculate the Weyl anomalies of the dual CFT.Comment: Added references, and minor corrections. 21 pages, havmac, no figure

Nonperturbative Effective Actions of N=2 Supersymmetric Gauge Theories

We elaborate on our previous work on N=2 supersymmetric Yang-Mills theory. In particular, we show how to explicitly determine the low energy quantum effective action for $G=SU(3)$ from the underlying hyperelliptic Riemann surface, and calculate the leading instanton corrections. This is done by solving Picard-Fuchs equations and asymptotically evaluating period integrals. We find that the dynamics of the $SU(3)$ theory is governed by an Appell system of type $F_4$, and compute the exact quantum gauge coupling explicitly in terms of Appell functions.Comment: 57p, harvmac with hyperlinks, 9 uuencoded ps figure

Lectures on Mirror Symmetry

We give an introduction to mirror symmetry of strings on Calabi-Yau manifolds with an emphasis on its applications e.g. for the computation of Yukawa couplings. We introduce all necessary concepts and tools such as the basics of toric geometry, resolution of singularities, construction of mirror pairs, Picard-Fuchs equations, etc. and illustrate all of this on a non-trivial example. Extended version of a lecture given at the Third Baltic Student Seminar, Helsinki September 1993Comment: LMU-TPW-94-02, 45 pages, harvma

Tachyon condensation and universality of DBI action

We show that a low-energy action for massless fluctuations around a tachyonic soliton background representing a codimension one D-brane coincides with the Dirac-Born-Infeld action. The scalar modes which describe transverse oscillations of the D-brane are translational collective coordinates of the soliton. The appearance of the DBI action is a universal feature independent of details of a tachyon effective action, provided it has the structure implied by the open string sigma model partition function.Comment: LaTex, 15 p. v2: references adde

On the Monodromies of N=2 Supersymmetric Yang-Mills Theory

We review the generalization of the work of Seiberg and Witten on N=2 supersymmetric SU(2) Yang-Mills theory to SU(n) gauge groups. The quantum moduli spaces of the effective low energy theory parametrize a special family of hyperelliptic genus n-1 Riemann surfaces. We discuss the massless spectrum and the monodromies.Comment: 15p, harvmac/lanlmac with hyperlinks, 4 uuencoded compressed postscript figures appende

Mirror Symmetry, Mirror Map and Applications to Complete Intersection Calabi-Yau Spaces

We extend the discussion of mirror symmetry, Picard-Fuchs equations, instanton-corrected Yukawa couplings, and the topological one-loop partition function to the case of complete intersections with higher-dimensional moduli spaces. We will develop a new method of obtaining the instanton-corrected Yukawa couplings through a close study of the solutions of the Picard-Fuchs equations. This leads to closed formulas for the prepotential for the K\"ahler moduli fields induced from the ambient space for all complete intersections in non singular weighted projective spaces. As examples we treat part of the moduli space of the phenomenologically interesting three-generation models that are found in this class. We also apply our method to solve the simplest model in which a topology change was observed and discuss examples of complete intersections in singular ambient spaces.Comment: 50 page

On the M-Theory Approach to (Compactified) 5D Field Theories

We construct M-theory curves associated with brane configurations of SU(N), SO(N) and $Sp(2N)$ 5d supersymmetric gauge theories compactified on a circle. From the curves we can account for all the existing different SU(N) field theories with $N_f \leq 2 N$. This is the correct bound for $N \geq 3$. We remark on the exceptional case SU(2). The bounds obtained for SO(N) and $Sp(2N)$ are $N_f\leq N-4$ and $N_f\leq 2N+4$, respectively.Comment: 18 pages, minor correction

Manejo de plantas daninhas na produção de arroz orgânico.

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Stepping through the Thin, Crackly Crust of the Present: Historians, Biographers, Novelists and Jack Burden

From the back of my copy of All the King\u27s Men I learned that Willie Stark is an important part of our collective literary consciousness, and that he is as memorable as Holden Caulfield or Huck Finn. This statement is both interesting and suspect, because Willie Stark is neither the focus of the novel nor its most compelling character. Apparently, though, charismatic politicians are infinitely more engaging than well-spoken, introspective, and witty writers - at least to some of Robert Penn Warren\u27s peers. Despite Jack Burden\u27s position as the protagonist in the novel, any simple plot summary of All the King\u27s Men will focus upon Willie Stark\u27s career and demise. Willie resonates with readers: he is not so specific as to preclude our memories of real politicians (particularly Huey P. Long, upon whom he is based), yet not so vague as to blend into the communal lull of characters we\u27ve encountered. So while Burden may be our narrator and interpreter, the focus of his attention is Willie, forcing the politician to the foreground. We follow Jack\u27s gaze - sometimes home to his mother, sometimes back in time to his adolescence, but always toward the capital and Willie - and can only view history through him. The novel is, then, almost a fictional memoir by Huey P. Long\u27s assistant, as it contains information about his boss, his job, and his personal life. The most compelling moments of the novel emerge when these three intersect, and when Jack attempts to interpret their implications. History is made through such attempts, and even if Jack is a fictional character, his insights ring clear in our world as well as his