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Experimental tests on the lifetime Asymmetry
The experimental test problem of the left-right polarization-dependent
lifetime asymmetry is discussed. It shows that the existing experiments cannot
demonstrate the lifetime asymmetry to be right or wrong after analyzing the
measurements on the neutron, the muon and the tau lifetime, as well as the
experiment. However, It is pointed out emphatically that the SLD and the
E158 experiments, the measurements of the left-right integrated cross section
asymmetry in boson production by collisions and by
electron-electron M{\o}ller scattering, can indirectly demonstrate the lifetime
asymmetry. In order to directly demonstrate the lifetime asymmetry, we propose
some possible experiments on the decays of polarized muons. The precise
measurement of the lifetime asymmetry could have important significance for
building a muon collider, also in cosmology and astrophysics. It would provide
a sensitive test of the standard model in particle physics and allow for
exploration of the possible interactions.Comment: 11 pages, 1 figur
High Sensitivity of Electron Transfer Rates within Nafion Coatings Saturated with Os(bpy)^(2+)_3 to the Extent of Hydration of the Coating
The sensitivity of the electrochemical responses obtained from electroactive counterions incorporated in Nafion coatings to the extent of hydration of the coatings^(27-38) is shown to be enhanced significantly when the electroactive ion is the only counterion present in the coating. Nafion coatings fully saturated with Os(bpy)^(2+)_3 exhibit unusually narrow and sharply peaked anodic currents in first-scan oxidative voltammograms. This voltammetric feature is accompanied by the
expulsion of one-third of the Os complex from the coating. The counterion actually ejected is primarily Os(bpy)^(3+)_3. As the Os(bpy)^(3+)_3 counterions are ejected, H_2O molecules enter the coatings. The quantity of H_2O molecules incorporated is so large that the mass of the coating (monitored with a quartz crystal microbalance) increases despite the ejection of the heavy Os(bpy)^(3+)_3 cations. After several voltammetric cycles, normally shaped voltammograms are obtained that are relatively
insensitive to the initial state of hydration of the coatings. The contrasting behaviors of hydrated and unhydrated coatings are compared, and possible explanations are offered for the differences observed
Quantum phase transition and engineering in two-component BEC in optical lattices
In this paper we review recent progress in studying quantum phase transitions
in one- and two-component Bose-Einstein condensates (BEC) in optical lattices.
These phase transitions involve the emergence and disappearance of quantum
coherence over whole optical lattice and of linear superposition of macroscopic
quantum states. The latter may provide new means to engineer and to manipulate
novel macroscopic quantum states and novel coherent atomic beams for quantum
information processing, quantum computing etc.Comment: Format: LaTex2e. 7 pages, no figure. Talk at the Yang Symposium (in
honor of C.N. Yang's 80th birthday), Beijing, China, June 2002. To appear in
the Proceeding
Left-Right Asymmetry of Weak Interaction Mass of Polarized Fermions in Flight
The left-right polarization-dependent asymmetry of the weak interaction mass
is investigated. Based on the Standard Model, the calculation shows that the
weak interaction mass of left-handed polarized fermions is always greater than
that of right-handed polarized fermions in flight with the same velocity in any
inertial frame. The asymmetry of the weak interaction mass might be very
important to the investigation of neutrino mass and would have an important
significance for understanding the parity nonconservation in weak interactions.Comment: 8 pages, 2 figures, corrected calculatio
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