1,249 research outputs found
Study of Asymptotic Free Scalar Field Theories from Adaptive Perturbation Method
We focus on the behavior of (2+1)d and (5+1)d
or theories in different regimes and compare the results
obtained from the adaptive perturbation method with those obtained from lattice
simulation. These theories are simple models that exhibit asymptotic freedom,
which is a property that is also observed in more complex theories such as QCD,
which describes the strong interaction between quarks and gluons. Asymptotic
freedom is an important feature of these theories because it allows for a
perturbative treatment of interactions at high energies. However, the standard
perturbation scheme breaks down in the presence of strong interactions, and the
adaptive perturbation method, which involves resuming the Feynman diagrams, is
more suitable for studying these interactions. Our research involves comparing
the perturbation result to lattice simulation. In the case of the
theory, there is no stable vacuum, so we explore evidence from the
theory instead. Our results appear to show that resummation improves the strong
coupling result for both the and theories.
Additionally, we improve the resummation method for the three-point coupling
vertex and study the RG flow to analyze the resummation contribution and
theoretical properties.Comment: 14 pages, 6 figures, minor change
Constrained Superfields and Standard Realization of Nonlinear Supersymmetry
A constrained superfield formalism has been proposed recently to analyze the
low energy physics related to Goldstinos. We prove that this formalism can be
reformulated in the language of standard realization of nonlinear
supersymmetry. New relations have been uncovered in the standard realization of
nonlinear supersymmetry.Comment: 8+1 pages, Latex, expanded discussions on scalar and vector field
Explore the Origin of SSB from Adaptive Perturbation Method
Spontaneous symmetry breaking occurs when the underlying laws of a physical
system are symmetric, but the vacuum state chosen by the system is not. The
(3+1)d theory is relatively simple compared to other more complex
theories, making it a good starting point for investigating the origin of
non-trivial vacua. The adaptive perturbation method is a technique used to
handle strongly coupled systems. It has been successful in strongly coupled QM
and is being generalized to scalar field theory to analyze the system in the
strong-coupling regime. The unperturbed Hamiltonian does not commute with the
usual number operator. However, the quantized scalar field admits a plane-wave
expansion when acting on the vacuum. While quantizing the scalar field theory,
the field can be expanded into plane-wave modes, making the calculations more
tractable. However, the Lorentz symmetry, which describes how physical laws
remain the same under certain spacetime transformations, might not be manifest
in this approach. The proposed elegant resummation of Feynman diagrams aims to
restore the Lorentz symmetry in the calculations. The results obtained using
this method are compared with numerical solutions for specific values of the
coupling constant . Finally, we find evidence for
quantum triviality, where self-consistency of the theory in the UV requires
. This result implies that the theory alone does not
experience SSB, and the phase is protected under the
RG-flow by a boundary of Gaussian fixed-points.Comment: 14 pages, 6 figures, minor change
High-speed, low cost test platform using FPGA technology
The object of this research is to develop a low-cost, adaptable testing platform for multi-GHz digital applications, with concentration on the test requirement of advanced devices. Since most advanced ATEs are very expensive, this equipment is not always available for testing cost-sensitive devices. The approach is to use recently-introduced advanced FPGAs for the core logic of the testing platform, thereby allowing for a low-cost, low power-consumption, high-performance, and adaptable test system. Furthermore to customize the testing system for specific applications, we implemented multiple extension testing modules base on this platform. With these extension modules, new functions can be added easily and the test system can be upgraded with specific features required for other testing purposes. The applications of this platform can help those digital devices to be delivered into market with shorter time, lower cost and help the development of the whole industry.Ph.D
Nonlinear Realization of Spontaneously Broken N=1 Supersymmetry Revisited
This paper revisits the nonlinear realization of spontaneously broken N=1
supersymmetry. It is shown that the constrained superfield formalism can be
reinterpreted in the language of standard realization of nonlinear
supersymmetry via a new and simpler route. Explicit formulas of actions are
presented for general renormalizable theories with or without gauge
interactions. The nonlinear Wess-Zumino gauge is discussed and relations are
pointed out for different definitions of gauge fields. In addition, a general
procedure is provided to deal with theories of arbitrary Kahler potentials.Comment: 1+18 pages, LaTe
Twin Pregnancy with Gastroschisis in Both Twins
SUMMARYObjectiveGastroschisis is a congenital malformation characterized by an abdominal wall defect located laterally to a normal umbilicus. The cause of gastroschisis is unknown, but most authors consider it exogenous. We describe the case of a woman with a twin pregnancy in which both twins had gastroschisis.Case ReportA 17-year-old primiparous female was referred to our institution because of a twin pregnancy, with one twin diagnosed with gastroschisis at 34 weeks of gestation. Unfortunately, gastroschisis was noted in both twins, but no other anomalies were observed under level II sonographic evaluation. The twins were delivered by cesarean section at 36+weeks of gestation because of preterm labor and breech presentation of one fetus. Both twins presented with a 3-cm abdominal wall defect located to the right side of the umbilicus and a large portion of the bowel protruding that was not covered by membrane. Histopathology of the placenta revealed that the twins were diamniotic monochorionic. Chromosomal analysis of cord blood showed normal karyotype (46, XX) in both newborns.ConclusionThe cause of gastroschisis is unknown, although possible exogenous causes have been studied. The diagnosis of gastroschisis in twin pregnancy is always in late gestation. Therefore, maternal serum alpha feto-protein screening and a detailed prenatal ultrasound evaluation are recommended in multifetal pregnancies
Drug and alcohol abuse at the work-place
Malaysia is the country that have strong legal control to the drug and alcohol among the Asia countries. Malaysia has prepared the guidelines that intended to provide guidance to employers and employees to prevent and respond to the issues from drug and alcohol use which to satisfy their obligations under the OSHA 1994. This action is to develop the prevention responses to the drug and alcohol issues in the workplace within Malaysia. There are many of issues that occurred in the workplace because the various forms of drug and alcohol that use by employees that effect their job performance when they are on duty especially operating machines such as alcohol, illicit drugs (heroin), non-predicate medicines (cough medicine) and others. Besides that, drug and alcohol abuse at the workplace may cause the risk injury of employees. Therefore, drug and alcohol use are totally prohibited in Malaysia and totally should be prevented in the workplace that can result in issues at work
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