146,276 research outputs found
On Gauge Theory and Topological String in Nekrasov-Shatashvili Limit
We study the Nekrasov-Shatashvili limit of the N=2 supersymmetric gauge
theory and topological string theory on certain local toric Calabi-Yau
manifolds. In this limit one of the two deformation parameters \epsilon_{1,2}
of the Omega background is set to zero and we study the perturbative expansion
of the topological amplitudes around the remaining parameter. We derive
differential equations from Seiberg-Witten curves and mirror geometries, which
determine the higher genus topological amplitudes up to a constant. We show
that the higher genus formulae previously obtained from holomorphic anomaly
equations and boundary conditions satisfy these differential equations. We also
provide a derivation of the holomorphic anomaly equations in the
Nekrasov-Shatashvili limit from these differential equations.Comment: 41 pages, no figure. v2: references adde
New Results on Massive 3-Loop Wilson Coefficients in Deep-Inelastic Scattering
We present recent results on newly calculated 2- and 3-loop contributions to
the heavy quark parts of the structure functions in deep-inelastic scattering
due to charm and bottom.Comment: Contribution to the Proc. of Loops and Legs 2016, PoS, in prin
Quantization of Even-Dimensional Actions of Chern-Simons Form with Infinite Reducibility
We investigate the quantization of even-dimensional topological actions of
Chern-Simons form which were proposed previously. We quantize the actions by
Lagrangian and Hamiltonian formulations {\`a} la Batalin, Fradkin and
Vilkovisky. The models turn out to be infinitely reducible and thus we need
infinite number of ghosts and antighosts. The minimal actions of Lagrangian
formulation which satisfy the master equation of Batalin and Vilkovisky have
the same Chern-Simons form as the starting classical actions. In the
Hamiltonian formulation we have used the formulation of cohomological
perturbation and explicitly shown that the gauge-fixed actions of both
formulations coincide even though the classical action breaks Dirac's
regularity condition. We find an interesting relation that the BRST charge of
Hamiltonian formulation is the odd-dimensional fermionic counterpart of the
topological action of Chern-Simons form. Although the quantization of two
dimensional models which include both bosonic and fermionic gauge fields are
investigated in detail, it is straightforward to extend the quantization into
arbitrary even dimensions. This completes the quantization of previously
proposed topological gravities in two and four dimensions.Comment: 50 pages, latex, no figure
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