3,511 research outputs found
Dual Field Theories In (d-1)+1 Emergent Spacetimes From A Unifying Field Theory In d+2 Spacetime
According to Two-Time Physics, there is more to space-time than can be
garnered with the ordinary formulation of physics. Two-Time Physics has shown
that the Standard Model of Particles and Forces is successfully reproduced by a
two-time field theory in 4 space and 2 time dimensions projected as a
holographic image on an emergent spacetime in 3+1 dimensions. Among the
successes of this approach is the resolution of the strong CP problem of QCD as
an outcome of the restrictions imposed by the higher symmetry structures in 4+2
dimensions. In this paper we launch a program to construct the duals of the
Standard Model as other holographic images of the same 4+2 dimensional theory
on a variety of emergent spacetimes in 3+1 dimensions. These dual field
theories are obtained as a family of gauge choices in the master 4+2 field
theory. In the present paper we deal with some of the simpler gauge choices
which lead to interacting Klein-Gordon field theories for the conformal scalar
with a predicted SO(d,2) symmetry in a variety of interesting curved spacetimes
in (d-1)+1 dimensions. More challenging and more interesting gauge choices
(including some that relate to mass) which are left to future work are also
outlined. Through this approach we discover a new realm of previously
unexplored dualities and hidden symmetries that exist both in the macroscopic
and microscopic worlds, at the classical and quantum levels. Such phenomena
predicted by 2T-physics can in principle be confirmed both by theory and
experiment. 1T-physics can be used to analyze the predictions but in most
instances gives no clue that the predicted phenomena exist in the first place.
This point of view suggests a new paradigm for the construction of a
fundamental theory that is likely to impact on the quest for unification.Comment: LaTeX, 35 page
The Big Bang and Inflation United by an Analytic Solution
Exact analytic solutions for a class of scalar-tensor gravity theories with a
hyperbolic scalar potential are presented. Using an exact solution we have
successfully constructed a model of inflation that produces the spectral index,
the running of the spectral index and the amplitude of scalar perturbations
within the constraints given by the WMAP 7 years data. The model simultaneously
describes the Big Bang and inflation connected by a specific time delay between
them so that these two events are regarded as dependent on each other. In
solving the Fridemann equations, we have utilized an essential Weyl symmetry of
our theory in 3+1 dimensions which is a predicted remaining symmetry of
2T-physics field theory in 4+2 dimensions. This led to a new method of
obtaining analytic solutions in 1T field theory which could in principle be
used to solve more complicated theories with more scalar fields. Some
additional distinguishing properties of the solution includes the fact that
there are early periods of time when the slow roll approximation is not valid.
Furthermore, the inflaton does not decrease monotonically with time, rather it
oscillates around the potential minimum while settling down, unlike the slow
roll approximation. While the model we used for illustration purposes is
realistic in most respects, it lacks a mechanism for stopping inflation. The
technique of obtaining analytic solutions opens a new window for studying
inflation, and other applications, more precisely than using approximations.Comment: V2 improve computation with better agreement with WMAP 7 years data,
and also point out an exact solution for cyclic cosmolog
Antidumping Petition: To File or Not To File
Given the ââŹĹnormal valueâ⏠of a product as common knowledge in an import-competing market, the profitability of a home firm in filing an antidumping (AD) petition against its foreign rival is shown to depend on the marginal cost differential between the home and foreign firms. When the marginal cost differential is ââŹĹsignificantly large,â⏠the home firm's ability to put the foreign firm at the risk of an AD violation is limited. But when the marginal cost differential is ââŹĹsignificantly small,â⏠the home firm is able to increase its output and lower the price of the product below its normal value, putting the foreign firm in the situation of an illegal dumping. One interesting implication is that, relative to the case without an AD law, the home firm has a stronger incentive to undertake cost-reducing activities (e.g., R&D investment or the adoption of a more efficient technology) under the law.antidumping laws, antidumping duties, dumping margins
Simultaneous pectoralis major-latissimus dorsi myocutaneous flap: An option of reconstruction for open sternal wounds
SummaryManagement of the open sternal wound after surgery is a challenge. We report a retrospective series of cases with regard to the management of sternal wounds according to our own experience and a review of the related literature. A retrospective chart review from June 2007 to February 2010 of patients with infective and open sternal wounds after surgery was performed. There were seven patients with a previous history of type A aortic dissection treated with the Bentall operation, thymoma with excision, mitral and tricuspid regurgitation with double valve replacement, and acute myocardial infarction with a ventricular-assist device or coronary artery bypass graft. All wound cultures of the seven patients showed positive findings. All patients received the latissimus dorsi (LD) myocutaneous flap for lower sternal wound reconstruction under the decubitus position and a contralateral pedicled rotated pectoralis major (PM) myocutaneous flap for the upper sternal wound. The residual wound was covered with a split-thickness skin graft. The mean age of the seven patients, including four males and three females, was 58.1 years (range: 33â73 years). The mean follow-up was 37.7 months (range: 30â44 months). The average time span between the final dĂŠbridement and the flap reconstruction procedure was 5.2 ¹ 1.8 days. The harvested area of LD myocutaneous flap ranged from 25 Ă 10 cm2 to 15 Ă 8 cm2, and the area of PM myocutaneous flap ranged from 15Ă15 cm2 to 10 Ă 5 cm2. Four of seven patients had an omental flap initially, but salvage surgery was performed using a simultaneous pectoralis major-LD flap. Three cases underwent simultaneous PM-LD flap directly. One patient expired on postoperative Day 4 because of sudden ventricular fibrillation, but no postoperative complications were noted in the other six patients. With long-term follow-up, all patients survived without significant complications. The simultaneous PM-LD myocutaneous flap is a reliable option for open sternal wound reconstruction
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