arXiv subjects

Seungjin Lee

Publications and source records attributed to Seungjin Lee.

21 records · Page 2Linked to original sources

arXiv2016

Non-linear gauge transformations in $D=10$ SYM theory and the BCJ duality

Recent progress on scattering amplitudes in super Yang--Mills and superstring theory benefitted from the use of multiparticle superfields. They universally capture tree-level subdiagrams, and their generating series solve the non-linear equations of ten-dimensional super Yang--Mills. We provide simplified recursions for multiparticle superfields and relate them to earlier representations through non-linear gauge transformations of their generating series. In this work we discuss the gauge transformations which enforce their Lie symmetries as suggested by the Bern-Carrasco-Johansson duality between color and kinematics. Another gauge transformation due to Harnad and Shnider is shown to streamline the theta-expansion of multiparticle superfields, bypassing the need to use their recursion relations beyond the lowest components. The findings of this work tremendously simplify the component extraction from kinematic factors in pure spinor superspace.

hep-th↗

arXiv2013

Higher Spin Contributions to Holographic Fluid Dynamics in $AdS_5/CFT_4$

We calculate the graviton's $β$-function in $AdS$ string-theoretic sigma-model, perturbed by vertex operators for Vasiliev's higher spin gauge fields in $AdS_5$. The result is given by $β_{mn}=R_{mn}+4T_{mn}(g,u)$ (with the AdS radius set to 1 and the graviton polarized along the $AdS_5$ boundary), with the matter stress-energy tensor given by that of conformal holographic fluid in $d=4$, evaluated at the temperature given by $T={1\overπ}$. The stress-energy tensor is given by $T_{mn}={g_{mn}}+4u_mu_n+\sum_{N}T^{(N)}_{mn}$ where $u$ is the vector excitation satisfying $u^2=-1$ and $N$ is the order of the gradient expansion in the dissipative part of the tensor. We calculate the contributions up to N=2. The higher spin excitations contribute to the $β$-function, ensuring the overall Weyl covariance of the matter stress tensor. We conjecture that the structure of gradient expansion in $d=4$ conformal hydrodynamics at higher orders is controlled by the higher spin operator algebra in $AdS_5$.

hep-th↗

arXiv2012

String Amplitudes and Frame-like Formalism for Higher Spins

We analyze open string vertex operators describing connection gauge fields for spin 3 in Vasiliev's frame-like formalism and perform their extended BRST analysis. Gauge symmetry transformations, generalized zero torsion constraints relating extra fields to the dynamical frame-like field and relation between dynamical frame-like field and fully symmetric Fronsdal's field for spin 3 are all realized in terms of BRST constraints on these vertex operators in string theory. Using the construction, we analyze the 3-point correlator for spin 3 field and calculate Chern-Simons type cubic interactions described by 3-derivative Berends-Burgers-van Dam (BBD) type vertex in the frame-like formalism.

hep-th↗