报告题目：Subsystem Trace Distance in Conformal Field Theory
报告时间：2019-06-10 15:30 (星期一)
报告地点：天津大学新校区理学院256
报告人：张甲举博士（意大利国际高等研究院(SISSA)）

报告摘要： 

 Wedevelop a systematic method to calculate the trace distance between two reduceddensity matrices in 1+1 dimensional quantum field theories. The approachexploits the path integral representation of the reduced density matrices andan ad hoc replica trick. We then extensively apply this method to thecalculation of the distance between reduced density matrices of one interval oflength l in eigenstates ofconformal field theories. When the interval is short, using the operatorproduct expansion of twist operators, we obtain a universal form for the leadingorder in l of the trace distance. Wecompute the trace distances among the reduced density matrices of several lowlying states in two-dimensional free massless boson and fermion theories. Wecompare our analytic conformal results with numerical calculations in XX andIsing spin chains finding perfect agreement.    

报告人简历：

张甲举博士，现就职于意大利国际高等研究院（SISSA）任博士后研究员。山东师范大学物理学学士，北京大学理论物理博士。曾先后在中国科学院高能物理研究所、意大利米兰比可卡大学任博士后研究员。  

代表作： 

[1]J. Zhang, P. Ruggiero and P. Calabrese, Subsystem Trace Distance in QuantumField Theory, Phys. Rev. Lett. 122 (2019) 141602, [1901.10993].  

[2]W.-Z. Guo, F.-L. Lin and J. Zhang, Distinguishing Black Hole Microstates usingHolevo Information, Phys. Rev. Lett. 121 (2018) 251603, [1808.02873]    

[3]H. Ouyang, J.-B. Wu and J.-j. Zhang, Supersymmetric Wilson loops in N = 4 superChern-Simons-matter theory, JHEP 11 (2015) 213, [1506.06192].  

[4]B. Chen and J.-j. Zhang, On short interval expansion of Renyi entropy, JHEP 11(2013) 164, [1309.5453].  

[5]B. Chen, S.-x. Liu and J.-j. Zhang, Thermodynamics of Black Hole Horizons andKerr/CFT Correspondence, JHEP 11 (2012) 017, [1206.2015].