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A brief history of the British Neuroscience Association
As the British Neuroscience Association commemorates 50 years of existence in 2018, this article recalls its founding as a discussion group, its establishment as the Brain Research Association, its transition to a professional society encompassing all aspects of neuroscience research, both clinical and non-clinical, and its re-branding as the British Neuroscience Association in the late 1990s. Neuroscience as a branch of life science has expanded hugely in the last 25 years and the British Neuroscience Association has adapted, frequently working with partner societies, to serve as an interdisciplinary hub for professionals working in this exciting and crucial field. The authors have attempted to highlight some key events in the Association’s history and acknowledge the contributions made by many people over half a century
Three-Nucleon Bound State in a Spin-Isospin Dependent Three Dimensional Approach
A spin-isospin dependent Three-Dimensional approach based on momentum vectors
for formulation of the three-nucleon bound state is presented in this paper.
The three-nucleon Faddeev equations with two-nucleon interactions are
formulated as a function of vector Jacobi momenta, specifically the magnitudes
of the momenta and the angle between them with the inclusion of the
spin-isospin quantum numbers, without employing a partial wave decomposition.
As an application the spin-isospin dependent Faddeev integral equations are
solved with Bonn-B potential. Our result for the Triton binding energy with the
value of -8.152 MeV is in good agreement with the achievements of the other
partial wave based methods.Comment: 24 pages, 1 figure, 7 tables. Major changes; version to appear in
Physical Review
Persistent currents in mesoscopic rings and boundary conformal field theory
A tight-binding model of electron dynamics in mesoscopic normal rings is
studied using boundary conformal field theory. The partition function is
calculated in the low energy limit and the persistent current generated as a
function of an external magnetic flux threading the ring is found. We study the
cases where there are defects and electron-electron interactions separately.
The same temperature scaling for the persistent current is found in each case,
and the functional form can be fitted, with a high degree of accuracy, to
experimental data.Comment: 6 pages, 4 enclosed postscript figure
Spin projection and spin current density within relativistic electronic transport calculations
A spin projection scheme is presented which allows the decomposition of the
electric conductivity into two different spin channels within fully
relativistic transport calculations that account for the impact
of spin-orbit coupling. This is demonstrated by calculations of the
spin-resolved conductivity of FeCr and CoPt disordered
alloys on the basis of the corresponding Kubo-Greenwood equation implemented
using the Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA)
band structure method. In addition, results for the residual resistivity of
diluted Ni-based alloys are presented that are compared to theoretical and
experimental ones that rely on Mott's two-current model for spin-polarized
systems. The application of the scheme to deal with the spin-orbit induced spin
Hall effect is discussed in addition
Covariant Helicity-Coupling Amplitudes: A New Formulation
We have worked out covariant amplitudes for any two-body decay of a resonance
with an arbitrary non-zero mass, which involves arbitrary integer spins in the
initial and the final states. One key new ingredient for this work is the
application of the total intrinsic spin operator which is given
directly in terms of the generators of the Poincar\'e group.
Using the results of this study, we show how to explore the Lorentz factors
which appear naturally, if the momentum-space wave functions are used to form
the covariant decay amplitudes. We have devised a method of constructing our
covariant decay amplitudes, such that they lead to the Zemach amplitudes when
the Lorentz factors are set one
Unambiguous pure state identification without classical knowledge
We study how to unambiguously identify a given quantum pure state with one of
the two reference pure states when no classical knowledge on the reference
states is given but a certain number of copies of each reference quantum state
are presented. By the unambiguous identification, we mean that we are not
allowed to make a mistake but our measurement can produce an inconclusive
result. Assuming the two reference states are independently distributed over
the whole pure state space in a unitary invariant way, we determine the optimal
mean success probability for an arbitrary number of copies of the reference
states and a general dimension of the state space. It is explicitly shown that
the obtained optimal mean success probability asymptotically approaches that of
the unambiguous discrimination as the number of the copies of the reference
states increases.Comment: v3: 8 pages, minor corrections, journal versio
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