Studien zur alttürkischen Daśakarmapathāvadānamālā (1) Die Udayana-Legende

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Śāriputra and the Girl Reborn as a Dog : A Further Tocharian B Parallel to the Old Uyghur Daśakarmapathāvadānamālā

Descriptive and Comparative Linguistic

Semi-device-dependent blind quantum tomography

Extracting tomographic information about quantum states is a crucial task in the quest towards devising high-precision quantum devices. Current schemes typically require measurement devices for tomography that are a priori calibrated to a high precision. Ironically, the accuracy of the measurement calibration is fundamentally limited by the accuracy of state preparation, establishing a vicious cycle. Here, we prove that this cycle can be broken and the fundamental dependence on the measurement devices significantly relaxed. We show that exploiting the natural low-rank structure of quantum states of interest suffices to arrive at a highly scalable blind tomography scheme with a classically efficient post-processing algorithm. We further improve the efficiency of our scheme by making use of the sparse structure of the calibrations. This is achieved by relaxing the blind quantum tomography problem to the task of de-mixing a sparse sum of low-rank quantum states. Building on techniques from model-based compressed sensing, we prove that the proposed algorithm recovers a low-rank quantum state and the calibration provided that the measurement model exhibits a restricted isometry property. For generic measurements, we show that our algorithm requires a close-to-optimal number measurement settings for solving the blind tomography task. Complementing these conceptual and mathematical insights, we numerically demonstrate that blind quantum tomography is possible by exploiting low-rank assumptions in a practical setting inspired by an implementation of trapped ions using constrained alternating optimization.Comment: 22 pages, 8 Figure

Quantum Games

In these lecture notes we investigate the implications of the identification of strategies with quantum operations in game theory beyond the results presented in [J. Eisert, M. Wilkens, and M. Lewenstein, Phys. Rev. Lett. 83, 3077 (1999)]. After introducing a general framework, we study quantum games with a classical analogue in order to flesh out the peculiarities of game theoretical settings in the quantum domain. Special emphasis is given to a detailed investigation of different sets of quantum strategies.Comment: 13 pages (LaTeX), 3 figure

Tocharian B Parallels to the Supāraga-Avadāna of the Old Uyghur Daśakarmapathāvadānamālā

The collection of Buddhist legends entitled Daśakarmapathāvadānamālā (DKPAM) is best preserved in Old Uyghur. According to the colophons of this Old Uyghur version, it was translated from Tocharian. In this paper, two Tocharian B fragments that are parallel to the Supāraga-Avadāna of the Old Uyghur DKPAM are presented, together with a third Tocharian B fragment that may belong to the same avadāna, but is so far lacking a parallel in Old Uyghur