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Page Covering All Events 
| 6:00 – 8:00 PM WEDNESDAY OCTOBER 1ST | ||
|---|---|---|
| Everyone gets together for beer and snacks at the Asgard (350 Massachusetts Ave, Cambridge) | ||
| THURSDAY OCTOBER 2ND | ||
| TIME |
MIT-CAMBRIDGE GROUP | QUANTUM INFORMATION RESEARCH OVERVIEW |
| 9:00
am |
M. Christandl, N.
Datta*, A.
Ekert, A. Landahl |
Perfect State Transfer in Quantum Spin Networks |
| <
Coffee |
Break > = 10:00 -
11:00 am |
||
| 11:00
am |
N. Boulant, D. Cory, J. Emerson, S. Furuta*, T. Havel | Random Unitary Processes and Incoherent Noise |
| < Lunch | Break > = 12:00 - whenever | ||
| Posters Up for Viewing All Afternoon – Lab Tours to be Arranged Individually | ||
| 6:00 – 9:00 PM THURSDAY OCTOBER 2ND | ||
| Dinner on the River (Henry Longfellow pickup at 6:00 sharp at the MIT sailing pavilion, Building 51) | ||
| FRIDAY OCTOBER 3RD | ||
| 9:00 am |
L.
Levitov, P. Littlewood, J. Keeling |
Angular Dependence of Radiation in Exciton Systems |
| < Coffee | Break > = 10:00 - 11:00 am | ||
| 11:00 am | C. Doran & T. Havel* | Lorentz Covariant Formulations of Multi-Qbit Dynamics via Geometric Algebra |
| < Lunch | Break > = 12:00 - whenever | ||
| Posters Up for Viewing All Afternoon – Lab Tours to be Arranged Individually | ||
| 1:30
pm, Center for Theoretical Physics
Seminar Room (building
6, 3rd floor) |
||
| Informal
Session on Quantum Algorithms (contact: Andrew
Landahl) |
||
| EVENING OF FRIDAY OCTOBER 3RD | ||
| Everybody
Does Exactly What They Want Suggestion: Come to dinner with most every one else at La Groceria at 7:00 pm (on a buy-your-own basis). |
||
This talk will briefly report on some recent CMI collaborative work
between myself and Nicolas Boulant (MIT). We define, explore and
characterize incoherent noise as examples of random unitary processes
in
certain experimental contexts. With concrete examples from NMR quantum
information processing, we demonstrate the problems and ambiguitites
for
process tomography that can arise from the presence of incoherent noise
in the state preparation process. We recongnise the importance of
characterizing the noise and suggest a method to extract an incoherence
profile which models the underlying inocoherent process. The profile
thus obtained can be used to apply control pulses to remove the
noise more efficiently.
Despite its remarkable success in providing a unified description of
diverse physical phenomena, quantum mechanics has a reputation for
being
mysterious. In large part this is due to a lack of geometric
interpretations for the states, observables and operations with which
it
deals. A noteworthy exception to this rule is the interpretation of the
state of a two-level quantum system as a unit vector in
three-dimensional Euclidean space, which is best known today as the Bloch vector. This allows the
two-dimensional complex-valued unit vector normally used to specify the
state, or wave vector as it is known, to be interpreted as the
Cayley-Klein parameters for a rotation of the Bloch vector from a
reference position to that of the state in question.
In this talk we will develop a generalization of this interpretation to
multiple two-level quantum systems and their subsystems, using
geometric
(aka Clifford) algebra as our main tool. More specifically, we will
represent both our states and operators in what we call the parity-even subalgebra, which is
isomorphic to a tensor product of quaternion algebras. We will use this
to introduce what Schrödinger called entanglement, namely the fact that
quantum systems cease to have well-defined individual states upon
interacting with one another. Entanglement with an unobservable
environment, in turn, gives rise to decoherence,
or the irreversible decay of quantum states into states that can be
interpreted as classical, albeit random, systems that are governed by
statistical mechanics. Finally, we will consider how decoherent changes
of state, or quantum operations,
might also be interpreted within the parity-even subalgebra.