4,198 research outputs found
Dirac Sea for Bosons I -- Formulation of Negative Energy Sea for Bosons
It is proposed to make formulation of second quantizing a bosonic theory by
generalizing the method of filling the Dirac negative energy sea for fermions.
We interpret that the correct vacuum for the bosonic theory is obtained by
adding minus one boson to each single particle negative energy states while the
positive energy states are empty. The boson states are divided into two sectors
; the usual positive sector with positive and zero numbers of bosons and the
negative sector with negative numbers of bosons. Once it comes into the
negative sector it cannot return to the usual positive sector by ordinary
interaction due to a barrier. It is suggested to use as a playground model in
which the filling of empty fermion Dirac sea and the removal of boson from the
negative energy states are not yet performed. We put forward such a naive
vacuum world in the present paper. The successive paper will concern a CPT-like
Theorem in the naive vacuum world.Comment: 24 pages, 2 figures, Latex; added refereces, corrected typo
Fast reaction limit of a three-component reaction–diffusion system
AbstractWe consider a three-component reaction–diffusion system with a reaction rate parameter, and investigate its singular limit as the reaction rate tends to infinity. The limit problem is given by a free boundary problem which possesses three regions separated by the free boundaries. One component vanishes and the other two components remain positive in each region. Therefore, the dynamics is governed by a system of two equations
Search for Effect of Influence from Future in Large Hadron Collider
We propose an experiment which consists of drawing a card and using it to
decide restrictions on the running of Large Hadron Collider (LHC for short) at
CERN, such as luminosity, and beam energy. There may potentially occur total
shut down. The purpose of such an experiment is to search for influence from
the future, that is, backward causation. Since LHC will produce particles of a
mathematically new type of fundamental scalars, i.e., the Higgs particles,
there is potentially a chance to find unseen effects, such as on influence
going from future to past, which we suggest in the present paper.Comment: 18pp, comments added, change of title and corrections of main text;
v4:minor typos correcte
Quality of life for persons with disabilities
The praxis of Christian social work in Japan needs to find a new direction due to social changes such as industrialization and technological development. Liberation theology has been responding to the critical stance toward the existing order and identifying with new movements for emancipation and justice. This paper analyzes the ethics of liberation theology and adapts it to the real life situation of people with disabilities in Japan. Chapter I deals with liberation theology and its ethics concerned with disabilities. It defines the measurement of ethics as a quality of life, so that the ethics can be examined in context. Chapter II introduces Japanese social changes as well as traditional ethics. Both ethics of Buddhism and Shintoism discriminate against persons with disabilities; industrialization also created a new type of discrimination and segregation against them, since disability was equated with unproductivity. Since medical technology cuts off human relationship by its system, disability and medical technological ethics were discussed. The paper then analyzes the present Japanese social welfare system and seeks a new dimension. Chapter III is the major research section: the life cycle analysis of a person with disabilities. Socio-psychological personality development is very important to analyze persons with disabilities since many of them were born disabled. Segregation and isolation by medical technology are damaging their personality development. The fetus stage deals with the DNA tests and abortion; the birth stage introduces the relationship between the medical technological system and human sensitivity such as odour, hearing, vision, and skinship; the infancy and early childhood stage discusses westernized changes and a new phenomena in Japan; the play age and school age deals with the Japanese school system and the segregation of children with disabilities; In the adolescent stage, persons with disabilities identify themselves as handicapped; The young adult and adulthood stage discusses institutional life and isolation from their families; The old age and termination of life stage introduces the isolated, dehumanized way life is terminated. The summary introduces the praxis at three levels: the intra personal level discusses self-liberation, participating in the movement; the inter-personal level suggests new church sacraments and the church community integrating people with disabilities into the Christian community; the meta-personal level discusses the social system changes through the consumer and independent living moments and the community-based rehabilitation system
Quark-Jet model for transverse momentum dependent fragmentation functions
In order to describe the hadronization of polarized quarks, we discuss an
extension of the quark-jet model to transverse momentum dependent fragmentation
functions. The description is based on a product ansatz, where each factor in
the product represents one of the transverse momentum dependent splitting
functions, which can be calculated by using effective quark theories. The
resulting integral equations and sum rules are discussed in detail for the case
of inclusive pion production. In particular, we demonstrate that the
3-dimensional momentum sum rules are satisfied naturally in this transverse
momentum dependent quark-jet model. Our results are well suited for numerical
calculations in effective quark theories, and can be implemented in Monte-Carlo
simulations of polarized quark hadronization processes.Comment: 19 pages, 4 figure
Localized and Expanding Entire Solutions of Reaction-Diffusion Equations
This paper is concerned with the spatio-temporal dynamics of nonnegative
bounded entire solutions of some reaction-diffusion equations in R N in any
space dimension N. The solutions are assumed to be localized in the past. Under
certain conditions on the reaction term, the solutions are then proved to be
time-independent or heteroclinic connections between different steady states.
Furthermore, either they are localized uniformly in time, or they converge to a
constant steady state and spread at large time. This result is then applied to
some specific bistable-type reactions
Phase transitions in spin-orbital coupled model for pyroxene titanium oxides
We study the competing phases and the phase transition phenomena in an
effective spin-orbital coupled model derived for pyroxene titanium oxides
ATiSi2O6 (A=Na, Li). Using the mean-field-type analysis and the numerical
quantum transfer matrix method, we show that the model exhibits two different
ordered states, the spin-dimer and orbital-ferro state and the spin-ferro and
orbital-antiferro state. The transition between two phases is driven by the
relative strength of the Hund's-rule coupling to the onsite Coulomb repulsion
and/or by the external magnetic field. The ground-state phase diagram is
determined. There is a keen competition between orbital and spin degrees of
freedom in the multicritical regime, which causes large fluctuations and
significantly affects finite-temperature properties in the paramagnetic phase.Comment: 4 pages, 6 figures, proceedings submitted to SPQS200
Glycosylation pattern of brush border-associated glycoproteins in enterocyte-like cells: involvement of complex-type N-glycans in apical trafficking
We have previously reported that galectin-4, a tandem repeat-type galectin, regulates the raft-dependent delivery of glycoproteins to the apical brush border membrane of enterocyte-like HT-29 cells. N-Acetyllactosamine-containing glycans, known as galectin ligands, were found enriched in detergent-resistant membranes. Here, we analyzed the potential contribution of N-and/ or O-glycans in this mechanism. Structural studies were carried out on the brush border membrane-enriched fraction using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and nano-ESI-QTOF-MS/MS. The pattern of N-glycans was very heterogeneous, with the presence of high mannose- and hybrid-type glycans as well as a multitude of complex-type glycans. In contrast, the pattern of O-glycans was very simple with the presence of two major core type 1 O-glycans, sialylated and bisialylated T-antigen structures {[}Neu5Ac alpha 2-3Gal beta 1-3GalNAc-ol and Neu5Ac alpha 2-3Gal beta 1 -3(Neu5Ac alpha 2-6)GalNAc-ol]. Thus, N-glycans rather than O-glycans contain the N-acetyllactosamine recognition signals for the lipid raft-based galectin-4-dependent apical delivery. In the presence of 1-deoxymannojirimycin, a drug which inhibits the generation of hybrid-type or complex type N-glycans, the extensively O-glycosylated mucin-like MUC1 glycoprotein was not delivered to the apical brush border but accumulated inside the cells. Altogether, our data demonstrate the crucial role of complex N-glycans in the galectin-4-dependent delivery of glycoproteins to the apical brush border membrane of enterocytic HT-29 cells
Scaling Behavior of Ricci Curvature at Short Distance near Two Dimensions
We study the renormalization of the Ricci curvature as an example of
generally covariant operators in quantum gravity near two dimensions. We find
that it scales with a definite scaling dimension at short distance. The Ricci
curvature singularity at the big bang can be viewed as such a scaling
phenomenon. The problem of the spacetime singularity may be resolved by the
scale invariance of the spacetime at short distance.Comment: 9pages, LaTe
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