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One of the most counterintuitive aspects of quantum theory is its claim that there is 'intrinsic' randomness in the physical world. Quantum information science has greatly progressed in the study of intrinsic, or secret, quantum randomness…

We study essentially bounded quantum random variables and show that the Gelfand spectrum of such a quantum random variable coincides with the hypoconvex hull of its essential range. Moreover, a notion of operator-valued variance is…

Quantum Physics · Physics 2015-10-07 Douglas Farenick , Michael J. Kozdron , Sarah Plosker

This paper is the continuation of a study into the information paradox problem started by the author in his earlier works. As previously, the key instrument is a deformed density matrix in quantum mechanics of the early universe. It is…

General Relativity and Quantum Cosmology · Physics 2009-11-10 A. E. Shalyt-Margolin

Non-relativistic quantum mechanics is reformulated here based on the idea that relational properties among quantum systems, instead of the independent properties of a quantum system, are the most fundamental elements to construct quantum…

Quantum Physics · Physics 2021-04-20 Jianhao M. Yang

Quantum statistics originate from the physics of state preparation. It is therefore wrong to think of quantum states as fundamental. In fact, quantum states are merely summaries of dynamical processes that randomize the properties of the…

Quantum Physics · Physics 2015-05-12 Holger F. Hofmann

Students in quantum mechanics class are taught that the wave function contains all knowable information about an isolated system. Later in the course, this view seems to be contradicted by the mysterious density matrix, which introduces a…

General Physics · Physics 2021-04-16 Mark G. Kuzyk

We consider a generalized model of repeated quantum interactions, where a system $\mathcal{H}$ is interacting in a random way with a sequence of independent quantum systems $\mathcal{K}_n, n \geq 1$. Two types of randomness are studied in…

Quantum Physics · Physics 2015-02-12 Ion Nechita , Clément Pellegrini

We study the problem of quantum-state tomography under the assumption that the state of the system is close to pure. In this context, an efficient measurements that one typically formulates uniquely identify a pure state from within the set…

Quantum Physics · Physics 2016-05-11 Amir Kalev , Charles H. Baldwin , Ivan H. Deutsch

Ensembles of random density matrices determined by various probability measures are analysed. A simple and efficient algorithm to generate at random density matrices distributed according to the Bures measure is proposed. This procedure may…

Statistical Mechanics · Physics 2010-03-31 Vladimir Al. Osipov , Hans-Juergen Sommers , Karol Zyczkowski

We present improved circuits intended for building a universal computer based on Random Pulse Computing (RPC) paradigm, a biologically-inspired way of computation in which variable is represented by a frequency of a Random Pulse Train (RPT)…

Emerging Technologies · Computer Science 2022-01-11 Mario Stipčević , Mateja Batelić

We review a recently proposed theory of random packings. We describe the volume fluctuations in jammed matter through a volume function, amenable to analytical and numerical calculations. We combine an extended statistical mechanics…

Soft Condensed Matter · Physics 2016-03-29 Chaoming Song , Ping Wang , Hernan A. Makse

Correlator product states (CPS) are a powerful and very broad class of states for quantum lattice systems whose amplitudes can be sampled exactly and efficiently. They work by gluing together states of overlapping clusters of sites on the…

Quantum Physics · Physics 2018-03-16 Stephen R. Clark

We define correlational (von Neumann) entropy for an individual quantum state of a system whose time-independent hamiltonian contains random parameters and is treated as a member of a statistical ensemble. This entropy is representation…

chao-dyn · Physics 2013-01-16 Valentin V. Sokolov , B. Alex Brown , Vladimir Zelevinsky

We review with a tutorial scope the information theory foundations of quantum statistical physics. Only a small proportion of the variables that characterize a system at the microscopic scale can be controlled, for both practical and…

Statistical Mechanics · Physics 2007-05-23 R. Balian

Recursive Fourier Sampling (RFS) was one of the earliest problems to demonstrate a quantum advantage, and is known to lie outside the Merlin--Arthur complexity class. This work contains a new description of quantum algorithms in phase space…

Quantum Physics · Physics 2025-08-20 Christoffer Hindlycke , Niklas Johansson , Jan-Åke Larsson

Undesired coupling to the surrounding environment destroys long-range correlations on quantum processors and hinders the coherent evolution in the nominally available computational space. This incoherent noise is an outstanding challenge to…

Quantum Physics · Physics 2024-11-07 A. Morvan , B. Villalonga , X. Mi , S. Mandrà , A. Bengtsson , P. V. Klimov , Z. Chen , S. Hong , C. Erickson , I. K. Drozdov , J. Chau , G. Laun , R. Movassagh , A. Asfaw , L. T. A. N. Brandão , R. Peralta , D. Abanin , R. Acharya , R. Allen , T. I. Andersen , K. Anderson , M. Ansmann , F. Arute , K. Arya , J. Atalaya , J. C. Bardin , A. Bilmes , G. Bortoli , A. Bourassa , J. Bovaird , L. Brill , M. Broughton , B. B. Buckley , D. A. Buell , T. Burger , B. Burkett , N. Bushnell , J. Campero , H. S. Chang , B. Chiaro , D. Chik , C. Chou , J. Cogan , R. Collins , P. Conner , W. Courtney , A. L. Crook , B. Curtin , D. M. Debroy , A. Del Toro Barba , S. Demura , A. Di Paolo , A. Dunsworth , L. Faoro , E. Farhi , R. Fatemi , V. S. Ferreira , L. Flores Burgos , E. Forati , A. G. Fowler , B. Foxen , G. Garcia , E. Genois , W. Giang , C. Gidney , D. Gilboa , M. Giustina , R. Gosula , A. Grajales Dau , J. A. Gross , S. Habegger , M. C. Hamilton , M. Hansen , M. P. Harrigan , S. D. Harrington , P. Heu , M. R. Hoffmann , T. Huang , A. Huff , W. J. Huggins , L. B. Ioffe , S. V. Isakov , J. Iveland , E. Jeffrey , Z. Jiang , C. Jones , P. Juhas , D. Kafri , T. Khattar , M. Khezri , M. Kieferová , S. Kim , A. Kitaev , A. R. Klots , A. N. Korotkov , F. Kostritsa , J. M. Kreikebaum , D. Landhuis , P. Laptev , K. -M. Lau , L. Laws , J. Lee , K. W. Lee , Y. D. Lensky , B. J. Lester , A. T. Lill , W. Liu , W. P. Livingston , A. Locharla , F. D. Malone , O. Martin , S. Martin , J. R. McClean , M. McEwen , K. C. Miao , A. Mieszala , S. Montazeri , W. Mruczkiewicz , O. Naaman , M. Neeley , C. Neill , A. Nersisyan , M. Newman , J. H. Ng , A. Nguyen , M. Nguyen , M. Yuezhen Niu , T. E. O'Brien , S. Omonije , A. Opremcak , A. Petukhov , R. Potter , L. P. Pryadko , C. Quintana , D. M. Rhodes , E. Rosenberg , C. Rocque , P. Roushan , N. C. Rubin , N. Saei , D. Sank , K. Sankaragomathi , K. J. Satzinger , H. F. Schurkus , C. Schuster , M. J. Shearn , A. Shorter , N. Shutty , V. Shvarts , V. Sivak , J. Skruzny , W. C. Smith , R. D. Somma , G. Sterling , D. Strain , M. Szalay , D. Thor , A. Torres , G. Vidal , C. Vollgraff Heidweiller , T. White , B. W. K. Woo , C. Xing , Z. J. Yao , P. Yeh , J. Yoo , G. Young , A. Zalcman , Y. Zhang , N. Zhu , N. Zobrist , E. G. Rieffel , R. Biswas , R. Babbush , D. Bacon , J. Hilton , E. Lucero , H. Neven , A. Megrant , J. Kelly , I. Aleiner , V. Smelyanskiy , K. Kechedzhi , Y. Chen , S. Boixo

In this paper a new formulation of quantum dynamics of totally constrained systems is developed, in which physical quantities representing time are included as observables. In this formulation the hamiltonian constraints are imposed on a…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Hideo Kodama

The reconstruction of quantum states from experimental measurements, often achieved using quantum state tomography (QST), is crucial for the verification and benchmarking of quantum devices. However, performing QST for a generic…

Quantum Physics · Physics 2024-10-07 Zhen Qin , Casey Jameson , Zhexuan Gong , Michael B. Wakin , Zhihui Zhu

Almost all novel observable phenomena in quantum optics are related to the quantum coherence. The coherence here is determined by the relative phase inside a state. Unfortunately, so far all the relevant experimental results in quantum…

Quantum Physics · Physics 2007-05-23 Wang Xiang-bin , Matsumoto Keiji , Tomita Akihisa

Quantum measurements can produce randomness arising from the uncertainty principle. When measuring a state with von Neumann measurements, the intrinsic randomness can be quantified by the quantum coherence of the state on the measurement…

Quantum Physics · Physics 2022-03-17 Hao Dai , Boyang Chen , Xingjian Zhang , Xiongfeng Ma