Measuring Thickness and Pretilt in Reflective Vertically Aligned Nematic Liquid Crystal Displays

Pretilt angle is a parameter of the utmost importance in the ultimate performance of vertically-aligned negative nematic LC displays. When these devices work in reflective mode, as is the LCOS microdisplays, accurate measurement of pretilt angles becomes a difficult problem, since usual experimental setups based on retardation of the polarization components of the impinging light are proportional to the product effective birefringence (neff - no) times thickness, and any attempt to separate these variables is cancelled out by symmetry. This work shows a relatively simple method capable of separating both variables. An experimental setup specifically aimed at vertically aligned reflective cells has been prepared. At the same time, a simulation model has been developed taking into account the properties of actual reflective displays. Comparison between experimental and theoretical results shows some discrepancies that can be explained assuming that the LC profile contains a residual twist. Including that twist in the model, an excellent agreement between theory and experiment has been achieved. Matching of simulations and measurements yields to the separate determination of pretilt angle and thickness and gives good estimates for the residual twist angle

Matter formed at the BNL relativistic heavy ion collider

We suggest that the "new form of matter" found just above $T_c$ by RHIC is made up of tightly bound quark-antiquark pairs, essentially 32 chirally restored (more precisely, nearly massless) mesons of the quantum numbers of $\pi$, $\sigma$, $\rho$ and $a_1$. Taking the results of lattice gauge simulations (LGS) for the color Coulomb potential from the work of the Bielefeld group and feeding this into a relativistic two-body code, after modifying the heavy-quark lattice results so as to include the velocity-velocity interaction, all ground-state eigenvalues of the 32 mesons go to zero at $T_c$ just as they do from below $T_c$ as predicted by the vector manifestation (VM in short) of hidden local symmetry. This could explain the rapid rise in entropy up to $T_c$ found in LGS calculations. We argue that how the dynamics work can be understood from the behavior of the hard and soft glue.Comment: Final versio

How Cereal Grass Shoots Perceive And Respond To Gravity

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141646/1/ajb208758.pd

Multibaryons with heavy flavors in the Skyrme model

We investigate the possible existence of multibaryons with heavy flavor quantum numbers using the bound state approach to the topological soliton model and the recently proposed approximation for multiskyrmion fields based on rational maps. We use an effective interaction lagrangian which consistently incorporates both chiral symmetry and the heavy quark symmetry including the corrections up to order 1/m_Q. The model predicts some narrow heavy flavored multibaryon states with baryon number four and seven.Comment: 8 pages, no figures, RevTe

Chiral effective action with heavy quark symmetry

We derive an effective action combining chiral and heavy quark symmetry, using approximate bosonization techniques of QCD. We explicitly show that the heavy-quark limit is compatible with the large $N_c$ (number of color) limit in the meson sector, and derive specific couplings between the light and heavy mesons ($D$, $D^*$, ...) and their chiral partners. The relevance of this effective action to solitons with heavy quarks describing heavy baryons is discussed.Comment: 14 pages, SUNY-NTG-92/2

Energy levels of the soliton--heavy-meson bound states

We investigate the bound states of heavy mesons with finite masses to a classical soliton solution in the Skyrme model. For a given model Lagrangian we solve the equations of motion exactly so that the heavy vector mesons are treated on the same footing as the heavy pseudoscalar mesons. All the energy levels of higher grand spin states as well as the ground state are given over a wide range of the heavy meson masses. We also examine the validity of the approximations used in the literatures. The recoil effect of finite mass soliton is naively estimated.Comment: 24 pages, REVTeX v3.0, 6 figures are available upon request

Quark Description of Hadronic Phases

We extend our proposal that major universality classes of hadronic matter can be understood, and in favorable cases calculated, directly in the microscopic quark variables, to allow for splitting between strange and light quark masses. A surprisingly simple but apparently viable picture emerges, featuring essentially three phases, distinguished by whether strangeness is conserved (standard nuclear matter), conserved modulo two (hypernuclear matter), or locked to color (color flavor locking). These are separated by sharp phase transitions. There is also, potentially, a quark phase matching hadronic K-condensation. The smallness of the secondary gap in two-flavor color superconductivity corresponds to the disparity between the primary dynamical energy scales of QCD and the much smaller energy scales of nuclear physics.Comment: 21 pages, 2 figure

Heavy Quark Solitons

We investigate the heavy baryons which arise as solitonic excitations in a ``heavy meson" chiral Lagrangian which includes the light vector particles. It is found that the effect of the light vectors may be substantial. We also present a simple derivation which clearly shows the connection to the Callan-Klebanov approach.Comment: 13 pages; LaTex; SU-4240-532; UR 1306/ER-40685-755 (Minor typos corrected

Excited ΛQ\Lambda_Q Baryons in the Large NcN_c Limit

The spectrum of excited $\Lambda_Q$-type heavy baryons is considered in the large $N_c$ limit. The universal form factors for $\Lambda_b$ semileptonic decay to excited charmed baryons are calculated in the large $N_c$ limit. We find that the Bjorken sum rule (for the slope of the Isgur--Wise function) and Voloshin sum rule (for the mass of the light degrees of freedom) are saturated by the first doublet of excited $\Lambda_Q$ states.Comment: 9 pages, use phyzzx, CALT-68-191