Talks

Quantum cryptography, quantum physics, cryptography, one-time pad, RSA, encryption, public key, decryption, private key, quantum computer, qubit, quantum key, distribution, QKD, Moore\'s Law, probability, quantum theory, complex number, beam splitter, superposition, electron orbital, Turing, quantum parallelism, EPR, Bell, information security

teaching relativity, Galilean relativity, Einstein\'s postulates, Lorentz-Einstein transformations, time, length, Galilean transformation equations, spatial separating, temporal separation, laws of mechanics, Maxwell\'s equations, Michelson-Morley

Institute of Science, A levels, boring, difficult, support for schools, girls in physics, advancing physics, physics education, celestia, videshell, quantum atomica, walter fend, physics lab, phet, modellus, clea, lancaster particle physics, many paths, seismology, stellarium, Alice law, warp, wintreb, datapoint, tinycad, falstad applets, spektrus, emanim

This talk is concerned with the noise-insensitive transmission of quantum information. For this purpose, the sender incorporates redundancy by mapping a given initial quantum state to a messenger state on a larger-dimensional Hilbert space. This encoding scheme allows the receiver to recover part of the initial information if the messenger system is corrupted by interaction with its environment. Our noise model for the transmission leaves a part of the quantum information unchanged, that is, we assume the presence of a noiseless subsystem or of a decoherence-free subspace. We address the case when the noiseless component cannot contain all the quantum information to be transmitted, and investigate how to best spread the information in a quantum state across the noise-susceptible components. (Joint work with David Kribs and Vern Paulsen.)

Nanostructured materials continue to be the focus of intense research due to their promise of innumerable practical applications as well as advancing the fundamental understanding of these intriguing materials. From physics, to chemistry, to biology, to computer science, across the engineering disciplines and into the imagination of the general event, nanotechnology has become an extremely popular buzzword that represents both hope and hype to many people. This talk will outline and describe the exploding field of nanotechnology, including its potential for promising new applications, and for negative societal implications that cause many to fear it. Recent work in our group in the area of integration of nanoscale structures with silicon will be outlined to show the scope and approaches to building nanoscale architectures; the applications of these frameworks include molecular computing, nanoscale sensing platforms, integration of silicon with biology, and intricate structures with unforeseen properties.

We will look at the axioms of quantum mechanics as expressed, for example, in the book by M. A. Nielsen and I. L. Chung ("Quantum Computation and Quantum Information"). We then take a critical look at these axioms, raising several questions as we go. In particular, we will look at the possible informational completeness property of the family of operators that we measure. We will propose physical solutions based on the results of quantum mechanics on phase space and the measurement of quantum particles by quantum mechanical means. We illustrate this with both momentum-position measurements and spin measurements.