William Wootters

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William Kent Wootters
Known forFounding quantum information theory
Quantum teleportation
Coffman–Kundu–Wootters inequality
Schrödinger–HJW theorem
Concurrence
Entanglement distillation
Entanglement of formation
No-cloning theorem
Problem of time
U-bit
Coining word "qubit"
Scientific career
Fields Theoretical physics

William "Bill" Kent Wootters is an American theoretical physicist, and one of the founders of the field of quantum information theory. In a 1982 joint paper with Wojciech H. Zurek, Wootters proved the no cloning theorem, [1] at the same time as Dennis Dieks, and independently of James L. Park who had formulated the no-cloning theorem in 1970. [2] [3] He is known for his contributions to the theory of quantum entanglement including quantitative measures of it, entanglement-assisted communication (notably quantum teleportation, discovered by Wootters and collaborators in 1993 [4] ) and entanglement distillation. The term qubit, denoting the basic unit of quantum information, originated in a conversation between Wootters and Benjamin Schumacher in 1992. [5]

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He earned a B.S. from Stanford University in 1973, and his Ph.D. from the University of Texas at Austin in 1980. His thesis was titled The Acquisition of Information from Quantum Measurements, and Linda Reichl was his doctoral advisor, while John A. Wheeler also served as a mentor. [6] He was a member of the physics department at Williams College from 1982 to 2017, receiving the title of Barclay Jermain Professor of Natural Philosophy. He was elected a fellow of the American Physical Society in 1999, for "contributions on the foundations of quantum mechanics and groundbreaking work in quantum information and communications theory." [7]

With Susan Loepp, he is the co-author of the book Protecting Information: From Classical Error Correction to Quantum Cryptography (Cambridge University Press, 2006). [8] [9]

See also

Related Research Articles

In physics, the no-cloning theorem states that it is impossible to create an independent and identical copy of an arbitrary unknown quantum state, a statement which has profound implications in the field of quantum computing among others. The theorem is an evolution of the 1970 no-go theorem authored by James Park, in which he demonstrates that a non-disturbing measurement scheme which is both simple and perfect cannot exist. The aforementioned theorems do not preclude the state of one system becoming entangled with the state of another as cloning specifically refers to the creation of a separable state with identical factors. For example, one might use the controlled NOT gate and the Walsh–Hadamard gate to entangle two qubits without violating the no-cloning theorem as no well-defined state may be defined in terms of a subsystem of an entangled state. The no-cloning theorem concerns only pure states whereas the generalized statement regarding mixed states is known as the no-broadcast theorem.

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In the interpretation of quantum mechanics, a local hidden-variable theory is a hidden-variable theory that satisfies the principle of locality. These models attempt to account for the probabilistic features of quantum mechanics via the mechanism of underlying, but inaccessible variables, with the additional requirement that distant events be statistically independent.

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References

  1. Wootters, W. K.; Zurek, W. H. (28 October 1982). "A single quantum cannot be cloned". Nature. 299 (5886): 802–803. Bibcode:1982Natur.299..802W. doi:10.1038/299802a0. ISSN   1476-4687. S2CID   4339227.
  2. D. Dieks, "Communication by EPR devices", Physics Letters A 92 (1982) 271–272.
  3. Park, James (1970). "The concept of transition in quantum mechanics". Foundations of Physics . 1 (1): 23–33. Bibcode:1970FoPh....1...23P. CiteSeerX   10.1.1.623.5267 . doi:10.1007/BF00708652. S2CID   55890485.
  4. C. H. Bennett; G. Brassard; C. Crépeau; R. Jozsa; A. Peres; W. K. Wootters (1993). "Teleporting an Unknown Quantum State via Dual Classical and Einstein–Podolsky–Rosen Channels". Phys. Rev. Lett. 70 (13): 1895–1899. Bibcode:1993PhRvL..70.1895B. CiteSeerX   10.1.1.46.9405 . doi:10.1103/PhysRevLett.70.1895. PMID   10053414.
  5. Fuchs, Christopher A.; Schlosshauer, Maximilian; Stacey, Blake C. (2015-05-10). "My Struggles with the Block Universe". arXiv: 1405.2390 [quant-ph].
  6. "William K. Wootters CV" (PDF). Science Center. Williams College . Retrieved 2019-03-24.
  7. "APS Fellow Archive". American Physical Society . Retrieved 2019-03-24.
  8. Review of Protecting Information by Fan Junjie (March 29, 2012), International Association for Cryptologic Research.
  9. Review of Protecting Information by Darren Glass (April 5, 2007), MAA Reviews, Mathematical Association of America.