41 research outputs found
Bulk from Bi-locals in Thermo Field CFT
We study the Large dynamics of the field theory in the Thermo
field dynamics approach. The question of recovering the high temperature phase
and the corresponding gauging is clarified. Through the associated
bi-local representation we discuss the emergent bulk space-time and
construction of (Higher spin) fields. We note the presence of `evanescent'
modes in this construction and also the mixing of spins at finite temperature.Comment: 24 page. v2: references added, minor corrections. v3: typo corrected,
clarification added, conclusion revised, version to appear in JHE
SYK-like Tensor Models on the Lattice
We study large tensor models on the lattice without disorder. We
introduce techniques which can be applied to a wide class of models, and
illustrate it by studying some specific rank-3 tensor models. In particular, we
study Klebanov-Tarnopolsky model on lattice, Gurau-Witten model (by treating it
as a tensor model on four sites) and also a new model which interpolates
between these two models. In each model, we evaluate various four point
functions at large and strong coupling, and discuss their spectrum and long
time behaviors. We find similarities as well as differences from SYK model. We
also generalize our analysis to rank- tensor models where we obtain
analogous results as case for the four point functions which we computed.
For , we are able to compute the next-to-subleading
corrections for a specific four point function.Comment: 46 pages, 29 figures; v2:typos corrected, reference added; v3:minor
revisions, to be published in JHE
SYK Models and SYK-like Tensor Models with Global Symmetry
In this paper, we study an SYK model and an SYK-like tensor model with global
symmetry. First, we study the large expansion of the bi-local collective
action for the SYK model with manifest global symmetry. We show that the global
symmetry is enhanced to a local symmetry at strong coupling limit, and the
corresponding symmetry algebra is the Kac-Moody algebra. The emergent local
symmetry together with the emergent reparametrization is spontaneously and
explicit broken. This leads to a low energy effective action. We evaluate four
point functions, and obtain spectrum of our model. We derive the low energy
effective action and analyze the chaotic behavior of the four point functions.
We also consider the recent 3D gravity conjecture for our model.
We also introduce an SYK-like tensor model with global symmetry. We first
study chaotic behavior of four point functions in various channels for the
rank-3 case, and generalize this into a rank- tensor model.Comment: 61 pages, 8 figures; v2: typos corrected, references added, appendix
D revised; v3: typos corrected, 1 figure added for clarification, substantial
revisions and clarifications (conclusions unchanged
On the Chaos Bound in Rotating Black Holes
We study out-of-time-order correlators (OTOCs) of rotating BTZ black holes
using two different approaches: the elastic eikonal gravity approximation, and
the Chern-Simons formulations of 3-dimensional gravity. Within both methods the
OTOC is given as a sum of two contributions, corresponding to left and right
moving modes. The contributions have different Lyapunov exponents,
, where
is the angular velocity and is the AdS radius. Since , there is an apparent contradiction with
the chaos bound. We discuss how the result can be made consistent with the
chaos bound if one views as the effective
inverse temperatures of the left and right moving modes.Comment: 35 pages, 2 figures. v2: references added, typos corrected, and
clarifications added to the discussion sectio