Triality in SU(2) Seiberg-Witten theory and Gauss hypergeometric function

Through AGT conjecture, we show how triality observed in \N=2 SU(2) N_f=4 QCD can be interpreted geometrically as the interplay among six of Kummer's twenty-four solutions belonging to one fixed Riemann scheme in the context of hypergeometric differential equations. We also stress that our presentation is different from the usual crossing symmetry of Liouville conformal blocks, which is described by the connection coefficient in the case of hypergeometric functions. Besides, upon solving hypergeometric differential equations at the zeroth order by means of the WKB method, a curve (thrice-punctured Riemann sphere) emerges. The permutation between these six Kummer's solutions then boils down to the outer automorphism of the associated curve.Comment: 16 pages; v2: references added, minor revision; Section 3.1.1 discussing N=2* SU(2) theory associated with a pinched once-punctured torus, Jack (or Gegenbauer) polynomials and Jacobi polynomials newly added; v3: Section 4 discussing "crossing symmetry and triality" & "geometric realization of triality" newly added thanks to PRD referee advice, to be published in PRD; v4: TexStyle changed onl

Classical c=1 Tachyon Scattering and 1/2-BPS Correlators

We study the correlator of chiral primary operators in \Ncal=4 super Yang-Mills theory in large $N$ limit. Through the free fermion picture, we map the gauge group rank and R-charges in SYM to the Fermi level and tachyon momenta, respectively, in the c=1 matrix model. By doing so, it is seen that half-BPS correlators are reproduced by tree-level tachyon scattering amplitudes.Comment: 7 pages, v2: typos corrected and a reference added, v3: PTP versio

Two Polyakov Loop Correlators from D5-branes at Finite Temperature

We study two Polyakov loop correlators in large $N$ limit of ${\cal{N}}=4$ super Yang-Mills theory at finite temperature using the AdS-Schwarzschild black hole. In the case that one of the two loops is of the anti-symmetric representation, we use D5-branes to evaluate them. The phase structure of these correlators is also examined. A previous result, derived in hep-th/9803135 and hep-th/9803137, is realized as a limiting case.}Comment: 12 pages, 2 figure

D-branes in the Lorentzian Melvin Geometry

We consider string theory on the Lorentzian Melvin geometry, which is obtained by analytically continuing the two-parameter Euclidean Melvin background. Because this model provides a solvable conformal field theory that describes time-dependent twisted string dynamics, we study the string one-loop partition function and the D-brane spectrum. We found that both the wrapping D2-brane and the codimension-one D-string emit winding strings, and this behavior can be traced to the modified open string Hamiltonian on these probe D-branes.Comment: 13 pages, v2,v3,v4: changes and references added, v5: final version in PT

Baxter's T-Q equation, SU(N)/SU(2)^{N-3} correspondence and \Omega-deformed Seiberg-Witten prepotential

We study Baxter's T-Q equation of XXX spin-chain models under the semiclassical limit where an intriguing SU(N)/SU(2)^{N-3} correspondence emerges. That is, two kinds of 4D \mathcal{N}=2 superconformal field theories having the above different gauge groups are encoded simultaneously in one Baxter's T-Q equation which captures their spectral curves. For example, while one is SU(N_c) with N_f=2N_c flavors the other turns out to be SU(2)^{N_c-3} with N_c hyper-multiplets (N_c > 3). It is seen that the corresponding Seiberg-Witten differential supports our proposal.Comment: 13 pages, 3 figures; v3: a mistaken upload; v4: a typo in arXiv title corrected (SU(N)=SU(2)^{N-3}---->SU(N)/SU(2)^{N-3}); v5: three references adde

Genus-one correction to asymptotically free Seiberg-Witten prepotential from Dijkgraaf-Vafa matrix model

We find perfect agreements on the genus-one correction to the prepotential of SU(2) Seiberg-Witten theory with N_f=2, 3 between field theoretical and Dijkgraaf-Vafa-Penner type matrix model results.Comment: 12 pages; v2: minor revision; v3: more structured, submitted versio

New Gauged Linear Sigma Models for 8D HyperKahler Manifolds and Calabi-Yau Crystals

We propose two kinds of gauged linear sigma models whose moduli spaces are real eight-dimensional hyperKahler and Calabi-Yau manifolds, respectively. Here, hyperKahler manifolds have sp(2) holonomy in general and are dual to Type IIB (p,q)5-brane configurations. On the other hand, Calabi-Yau fourfolds are toric varieties expressed as quotient spaces. Our model involving fourfolds is different from the usual one which is directly related to a symplectic quotient procedure. Remarkable features in newly-found three-dimensional Chern-Simons-matter theories appear here as well, such as dynamical Fayet-Iliopoulos parameters, one dualized photon and its residual discrete gauge symmetry.Comment: 20 pages, 1 figure; v2: minor changes and references added; v3: statements improved, newer than JHEP versio

Uniformization, Calogero-Moser/Heun duality and Sutherland/bubbling pants

Inspired by the work of Alday, Gaiotto and Tachikawa (AGT), we saw the revival of Poincar{\'{e}}'s uniformization problem and Fuchsian equations obtained thereof. Three distinguished aspects are possessed by Fuchsian equations. First, they are available via imposing a classical Liouville limit on level-two null-vector conditions. Second, they fall into some A_1-type integrable systems. Third, the stress-tensor present there (in terms of the Q-form) manifests itself as a kind of one-dimensional "curve". Thereby, a contact with the recently proposed Nekrasov-Shatashvili limit was soon made on the one hand, whilst the seemingly mysterious derivation of Seiberg-Witten prepotentials from integrable models become resolved on the other hand. Moreover, AGT conjecture can just be regarded as a quantum version of the previous Poincar{\'{e}}'s approach. Equipped with these observations, we examined relations between spheric and toric (classical) conformal blocks via Calogero-Moser/Heun duality. Besides, as Sutherland model is also obtainable from Calogero-Moser by pinching tori at one point, we tried to understand its eigenstates from the viewpoint of toric diagrams with possibly many surface operators (toric branes) inserted. A picture called "bubbling pants" then emerged and reproduced well-known results of the non-critical self-dual c=1 string theory under a "blown-down" limit.Comment: 17 pages, 4 figures; v2: corrections and references added; v3: Section 2.4.1 newly added thanks to JHEP referee advice. That classical four-point spheric conformal blocks reproducing known SW prepotentials is demonstrated via more examples, to appear in JHEP; v4: TexStyle changed onl