1,454 research outputs found
The Industrial Organization of the Japanese Bar: Levels and Determinants of Attorney Income
Using micro-level data on attorney incomes in 2004, we reconstruct the industrial organization of the Japanese legal services industry. These data suggest a somewhat bifurcated bar, with two sources of unusually high income: talent in Tokyo, and scarcity elsewhere. The most talented would-be lawyers (those with the highest opportunity costs) pass the bar-exam equivalent on one of their first tries or abandon the effort. If they pass, they tend to opt for careers in Tokyo that involve complex litigation and business transactions. This work places a premium on their talent, and from it they earn appropriately high incomes. The less talented face lower opportunity costs, and willingly spend many years studying for the exam. If they eventually pass, they disproportionately forego the many amenities available to professional families in Tokyo and opt instead for careers in the under-lawyered provinces. There, they earn scarcity and monopoly rents not available in the far more competitive Tokyo market.lawyers; Japan
Purification through Zeno-like Measurements
A series of frequent measurements on a quantum system (Zeno-like
measurements) is shown to result in the ``purification'' of another quantum
system in interaction with the former. Even though the measurements are
performed on the former system, their effect drives the latter into a pure
state, irrespectively of its initial (mixed) state, provided certain conditions
are satisfied.Comment: REVTeX4, 4 pages, 1 figure; to be published in Phys. Rev. Lett.
(2003
Macroscopic limit of a solvable dynamical model
The interaction between an ultrarelativistic particle and a linear array made
up of two-level systems (^^ ^^ AgBr" molecules) is studied by making use of
a modified version of the Coleman-Hepp Hamiltonian. Energy-exchange processes
between the particle and the molecules are properly taken into account, and the
evolution of the total system is calculated exactly both when the array is
initially in the ground state and in a thermal state. In the macroscopic limit
(), the system remains solvable and leads to interesting
connections with the Jaynes-Cummings model, that describes the interaction of a
particle with a maser. The visibility of the interference pattern produced by
the two branch waves of the particle is computed, and the conditions under
which the spin array in the limit behaves as a ^^ ^^
detector" are investigated. The behavior of the visibility yields good insights
into the issue of quantum measurements: It is found that, in the
thermodynamical limit, a superselection-rule space appears in the description
of the (macroscopic) apparatus. In general, an initial thermal state of the ^^
^^ detector" provokes a more substantial loss of quantum coherence than an
initial ground state. It is argued that a system decoheres more as the
temperature of the detector increases. The problem of ^^ ^^ imperfect
measurements" is also shortly discussed.Comment: 30 pages, report BA-TH/93-13
On the Courant-Fischer theory for Krein spaces
http://www.sciencedirect.com/science/article/B6V0R-4V462G8-2/2/25c16be9e99d2fbaa89b7c1a6a47e95
Live imaging of whole mouse embryos during gastrulation : migration analyses of epiblast and mesodermal cells
During gastrulation in the mouse embryo, dynamic cell movements including epiblast invagination and mesodermal layer expansion lead to the establishment of the three-layered body plan. The precise details of these movements, however, are sometimes elusive, because of the limitations in live imaging. To overcome this problem, we developed techniques to enable observation of living mouse embryos with digital scanned light sheet microscope (DSLM). The achieved deep and high time-resolution images of GFP-expressing nuclei and following 3D tracking analysis revealed the following findings: (i) Interkinetic nuclear migration (INM) occurs in the epiblast at embryonic day (E)6 and 6.5. (ii) INM-like migration occurs in the E5.5 embryo, when the epiblast is a monolayer and not yet pseudostratified. (iii) Primary driving force for INM at E6.5 is not pressure from neighboring nuclei. (iv) Mesodermal cells migrate not as a sheet but as individual cells without coordination
Curvature effect on nuclear pasta: Is it helpful for gyroid appearance?
In supernova cores and neutron star crusts, nuclei are thought to deform to
rodlike and slablike shapes, which are often called nuclear pasta. We study the
equilibrium properties of the nuclear pasta by using a liquid drop model with
curvature corrections. It is confirmed that the curvature effect acts to lower
the transition densities between different shapes. We also examine the gyroid
structure, which was recently suggested as a different type of nuclear pasta by
analogy with the polymer systems. The gyroid structure investigated in this
paper is approximately formulated as an extension of the periodic minimal
surface whose mean curvature vanishes. In contrast to our expectations, we find
from the present approximate formulation that the curvature corrections act to
slightly disfavor the appearance of the gyroid structure. By comparing the
energy corrections in the gyroid phase and the hypothetical phases composed of
d-dimensional spheres, where d is a general dimensionality, we show that the
gyroid is unlikely to belong to a family of the generalized dimensional
spheres.Comment: 14 pages, 8 figure
Exponential behavior of a quantum system in a macroscopic medium
An exponential behavior at all times is derived for a solvable dynamical
model in the weak-coupling, macroscopic limit. Some implications for the
quantum measurement problem are discussed, in particular in connection with
dissipation.Comment: 8 pages, report BA-TH/94-17
Spectral resolution of the Liouvillian of the Lindblad master equation for a harmonic oscillator
A Lindblad master equation for a harmonic oscillator, which describes the
dynamics of an open system, is formally solved. The solution yields the
spectral resolution of the Liouvillian, that is, all eigenvalues and
eigenprojections are obtained. This spectral resolution is discussed in depth
in the context of the biorthogonal system and the rigged Hilbert space, and the
contribution of each eigenprojection to expectation values of physical
quantities is revealed. We also construct the ladder operators of the
Liouvillian, which clarify the structure of the spectral resolution.Comment: 22pages, no figure; title changed, minor corrections, references
added; minor correction
Initial wave packets and the various power-law decreases of scattered wave packets at long times
The long time behavior of scattered wave packets from a
finite-range potential is investigated, by assuming to be
initially located outside the potential. It is then shown that can
asymptotically decrease in the various power laws at long time, according to
its initial characteristics at small momentum. As an application, we consider
the square-barrier potential system and demonstrate that exhibits
the asymptotic behavior , while another behavior like can
also appear for another .Comment: 5 pages, 1 figur
Stability and instability in parametric resonance and quantum Zeno effect
A quantum mechanical version of a classical inverted pendulum is analyzed.
The stabilization of the classical motion is reflected in the bounded evolution
of the quantum mechanical operators in the Heisenberg picture. Interesting
links with the quantum Zeno effect are discussed.Comment: 6 pages, 3 figure
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