**Theory Seminar**

KEK 素粒子原子核研究所 理論セミナー

TITLE： | Closed string transport coefficients and the membrane paradigm |

(in English) | |

SPEAKER： |
Dr. Yuya Sasai
(University of Helsinki) |

DATE： | December 20 (Tue.) 11:00 − 12:00 |

PLACE: | Kenkyu Honkan 1F, Meeting Room 1 |

（ABSTRACT）

I discuss a correspondence between a fictitious fluid in the black hole membrane paradigm and highly excited closed string states according to the black hole correspondence principle. I calculate the membrane transport coefficients of an electric NS-NS 2-charged black hole and transport coefficients of the highly excited closed string states which possess a Kaluza-Klein number and a winding number. Comparing both the transport coefficients at the correspondence point, I show that, except for the bulk viscosity, the membrane transport coefficients are of the same order as the transport coefficients of the closed string states on the stretched horizon. Also, I show that, except for the bulk viscosity, both the dimensionless transport coefficients, which are defined by dividing the transport coefficients by the entropy density, are exactly equal if the central charge is 6.