On a Nielsen-Thurston classification theory for cluster modular groups

We classify elements of a cluster modular group into three types. We characterize them in terms of fixed point property of the action on the tropical compactifications associated with the corresponding cluster ensemble. The characterization gives an analogue of the Nielsen-Thurston classification theory on the mapping class group of a surface.Comment: 33 pages, 9 figures. To appear in Annales de l'Institut Fourie

Conformal Quantum Mechanics and Sine-Square Deformation

We revisit conformal quantum mechanics (CQM) from the perspective of sine-square deformation (SSD) and the entanglement Hamiltonian. The operators that correspond to SSD and the entanglement Hamiltonian are identified. Thus, the nature of SSD and entanglement can be discussed in a much simpler CQM setting than higher-dimensional field theories

An Extreme Black Hole with Electric Dipole Moment

We construct a new extreme black hole solution in toroidally compactified heterotic string theory. The black hole saturates the Bogomol'nyi bound, has zero angular momentum, but nonzero electric dipole moment. It is obtained by starting with a higher dimensional rotating charged black hole, and compactifying one direction in the plane of rotation.Comment: 12 pages, RevTeX, 2up style PostScript file available at http://pentexts.itp.ucsb.edu/PS/HT.ps (reference added