3,241 research outputs found
On the Relation Between Quantum Mechanical and Classical Parallel Transport
We explain how the kind of ``parallel transport'' of a wavefunction used in
discussing the Berry or Geometrical phase induces the conventional parallel
transport of certain real vectors. These real vectors are associated with
operators whose commutators yield diagonal operators; or in Lie algebras those
operators whose commutators are in the (diagonal) Cartan subalgebra.Comment: 3 pages, no figure
Neutron Acceleration in Uniform Electromagnetic Fields
The question as to whether neutron acceleration can occur in uniform
electromagnetic fields is examined. Although such an effect has been predicted
using the canonical equations of motion some doubt has been raised recently as
to whether it is in principle observable for a spin 1/2 particle. To resolve
this issue a gedanken experiment is proposed and analyzed using a wave packet
construction for the neutron beam. By allowing arbitrary orientation for the
neutron spin as well as for the electric and magnetic fields a non vanishing
acceleration of the center of the neutron wave packet is found which confirms
the predictions of the canonical formalism.Comment: 11 page
Non-locality of Quantum Mechanics and the Locality of General Relativity
The conflict between the locality of general relativity, reflected in its
space-time description, and the non-locality of quantum mechanics, contained in
its Hilbert space description, is discussed. Gauge covariant non-local
observables that depend on gauge fields and gravity as well as the wave
function are used in order to try to understand and minimize this conflict
within the frame-work of these two theories. Applications are made to the
Aharonov-Bohm effect and its generalizations to non Abelian gauge fields and
gravity.Comment: 14 pages, 1 figure. Invited talk at the Meeting on the Interface of
Gravitational and Quantum Realms, IUCAA, Pune, India, Dec. 17-21, 2001. To be
published in Modern Physics Letters
Online Application Monitoring Tool
In some classes, students take online tests and some types of network activity (for example trying to find the answers in www.google.com) will be considered as cheating during the exam. It would be useful if instructor could monitor online activities of each student to detect cheating. The goal of this project is to develop such a tool using client/server architecture. Tool should display the student\u27s hostname and the website visited during unauthorized web activity. Professor should able to see the applications opened by all students and he will have an option to view the log files of all the students during the session and also at the end of the session. The tool will display the student\u27s hostname during login and logout from the network
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