15,385 research outputs found
Conference Review: Heroism and the Heroic in Applied and Social Theatre
In March 2014, the TaPRA Applied and Social Theatre Working Group held a research day at the Royal Central School Speech and Drama (RCSSD) exploring the significance and implications of the notion of heroism in socially engaged theatre practice. Heroism as a theme emerged from discussions at the end of the last annual TaPRA conference in Glasgow in 2013, which led the working group convenors (Sylvan Baker, Dave Calvert, Alison Jeffers & Katharine Low) into discussions on risk and bravery in applied and social theatre from which have emerged ideas about care and protection, both of participants and of practitioners. Another strong theme to emerge from our conversations on heroism was the notion of leadership; different models of leadership, and changing perceptions of self in leadership roles. Is heroism always epic or can we identify small acts of everyday heroism and is it at all helpful to think in these terms? Does thinking about heroism lead to a certain romanticisation of applied theatre
Reciprocal relativity of noninertial frames: quantum mechanics
Noninertial transformations on time-position-momentum-energy space {t,q,p,e}
with invariant Born-Green metric ds^2=-dt^2+dq^2/c^2+(1/b^2)(dp^2-de^2/c^2) and
the symplectic metric -de/\dt+dp/\dq are studied. This U(1,3) group of
transformations contains the Lorentz group as the inertial special case. In the
limit of small forces and velocities, it reduces to the expected Hamilton
transformations leaving invariant the symplectic metric and the nonrelativistic
line element ds^2=dt^2. The U(1,3) transformations bound relative velocities by
c and relative forces by b. Spacetime is no longer an invariant subspace but is
relative to noninertial observer frames. Born was lead to the metric by a
concept of reciprocity between position and momentum degrees of freedom and for
this reason we call this reciprocal relativity.
For large b, such effects will almost certainly only manifest in a quantum
regime. Wigner showed that special relativistic quantum mechanics follows from
the projective representations of the inhomogeneous Lorentz group. Projective
representations of a Lie group are equivalent to the unitary reprentations of
its central extension. The same method of projective representations of the
inhomogeneous U(1,3) group is used to define the quantum theory in the
noninertial case. The central extension of the inhomogeneous U(1,3) group is
the cover of the quaplectic group Q(1,3)=U(1,3)*s H(4). H(4) is the
Weyl-Heisenberg group. A set of second order wave equations results from the
representations of the Casimir operators
Study of photoconductive indium antimonide
Indium antimonide (InSb) material was assessed for use as photoconductive infrared detectors under low background conditions. Such detectors must be more rugged, and have lower capacitance, than the common photovoltaic InSb detector. Electronic grade n-type InSb was etched to 50 micrometers thickness, and tin and gold contacts were applied by evaporation. The test devices showed a relatively low ultimate impedance: 7 Mohms at 4.2 K. This was attributed to the presence of impurity levels of very shallow energies, and this material was judged unsuitable for low background detection
Optimization flow control -- I: Basic algorithm and convergence
We propose an optimization approach to flow control where the objective is to maximize the aggregate source utility over their transmission rates. We view network links and sources as processors of a distributed computation system to solve the dual problem using a gradient projection algorithm. In this system, sources select transmission rates that maximize their own benefits, utility minus bandwidth cost, and network links adjust bandwidth prices to coordinate the sources' decisions. We allow feedback delays to be different, substantial, and time varying, and links and sources to update at different times and with different frequencies. We provide asynchronous distributed algorithms and prove their convergence in a static environment. We present measurements obtained from a preliminary prototype to illustrate the convergence of the algorithm in a slowly time-varying environment. We discuss its fairness property
Lepton Family Symmetry and Neutrino Mass Matrix
The standard model of leptons is extended to accommodate a discrete Z_3 X Z_2
family symmetry. After rotating the charged-lepton mass matrix to its diagonal
form, the neutrino mass matrix reveals itself as very suitable for explaining
atmospheric and solar neutrino oscillation data. A generic requirement of this
approach is the appearance of three Higgs doublets at the electroweak scale,
with observable flavor violating decays.Comment: 9 pages, including 1 figur
Simulation of the Spin Field Effect Transistors: Effects of Tunneling and Spin Relaxation on its Performance
A numerical simulation of spin-dependent quantum transport for a spin field
effect transistor (spinFET) is implemented in a widely used simulator nanoMOS.
This method includes the effect of both spin relaxation in the channel and the
tunneling barrier between the source/drain and the channel. Account for these
factors permits setting more realistic performance limits for the transistor,
especially the magnetoresistance, which is found to be lower compared to
earlier predictions. The interplay between tunneling and spin relaxation is
elucidated by numerical simulation. Insertion of the tunneling barrier leads to
an increased magnetoresistance. Numerical simulations are used to explore the
tunneling barrier design issues.Comment: 31 pages, 14 figures, submitted to Journal of Applied Physic
Diquark in Nona-quark States
We study the nonaquark states and which are reported
by KEK-PS (Phys.Lett. B597 (2004) 236; nucl-ex/0310018) by means of the quark
model with diquark correlation. The nonaquark states form
SU(3) multiplets.
The flavor wave functions of all the nonaquark states are constructed through
the standard tensor technique. The mass spectrum is studied by using
Gell-Mann-Okubo mass formula. Some nonaquark mass sum rules are obtained. We
further investigate the decay of and under the
assumption of "fall-apart" mechanism. It has been found that the main decay
mode is rather than which is consistent with
experiment. Also we have uniquely determine the flavor wave function of
which belong to -plet with the quantum number
. Whereas the exotic states can belong to either
-plet or -plet. In the exact limit, both and
belong to -plet with negative parity. We predict that its flavor
structure can be determined by measuring the branch fractions of its decay
channels. The experiments to check this prediction are expected.Comment: 23 pages, 8 figures, to appear in Phys. Rev.
Corrections to deuterium hyperfine structure due to deuteron excitations
We consider the corrections to deuterium hyperfine structure originating from
the two-photon exchange between electron and deuteron, with the deuteron
excitations in the intermediate states. In particular, the motion of the two
intermediate nucleons as a whole is taken into account. The problem is solved
in the zero-range approximation. The result is in good agreement with the
experimental value of the deuterium hyperfine splitting.Comment: 7 pages, LaTe
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