scholarly journals Dynamics of heteropolymers in dilute solution: Effective equation of motion and relaxation spectrum

1996 ◽  
Vol 54 (5) ◽  
pp. 5340-5357 ◽  
Author(s):  
Jiunn-Ren Roan ◽  
E. I. Shakhnovich
Keyword(s):  
Relaxation Spectrum ◽  
Equation Of Motion ◽  
Dilute Solution ◽  
Effective Equation

scholarly journals A TOPOLOGICAL EXTENSION OF GENERAL RELATIVITY TO EXPLORE THE NATURE OF QUANTUM SPACETIME, DARK ENERGY AND INFLATION

2013 ◽  
Vol 22 (10) ◽  
pp. 1330022
Author(s):  
M. SPAANS
Keyword(s):  
General Relativity ◽  
Dark Energy ◽  
Discrete Time ◽  
Thought Experiment ◽  
Planck Scale ◽  
Equation Of Motion ◽  
Effective Equation ◽  
Dark Energy Density ◽  
Topological Quantum ◽  
Quantum Spacetime

General Relativity is extended into the quantum domain. A thought experiment is explored to derive a specific topological build-up for Planckian spacetime. The presented arguments are inspired by Feynman's path integral for superposition and Wheeler's quantum foam of Planck mass mini black holes (BHs)/wormholes. Paths are fundamental and prime three-manifolds like T3, S1 × S2 and S3 are used to construct quantum spacetime. A physical principle is formulated that causes observed paths to multiply: It takes one to know one. So topological fluctuations on the Planck scale take the form of multiple copies of any homeomorphically distinct path through quantum spacetime. The discrete time equation of motion for this topological quantum gravity is derived by counting distinct paths globally. The equation of motion is solved to derive some properties of dark energy and inflation. The dark energy density depends linearly on the number of macroscopic BHs in the universe and is time-dependent in a manner consistent with current astrophysical observations, having an effective equation of state w ≈ -1.1 for redshifts smaller than unity. Inflation driven by mini BHs proceeds over n ≈ 55 e-foldings, without strong inhomogeneity. A discrete time effect visible in the cosmic microwave background is suggested.

MOMENTS OF THE SPIN-DEPENDENT PROTON STRUCTURE FUNCTION

1990 ◽  
Vol 05 (14) ◽  
pp. 1125-1130
Author(s):  
D. INDUMATHI ◽  
M. V. N. MURTHY ◽  
V. RAVINDRAN
Keyword(s):  
Structure Function ◽  
Operator Product Expansion ◽  
Equation Of Motion ◽  
Proton Structure Function ◽  
Operator Product ◽  
Effective Equation ◽  
The Third ◽  
Proton Structure ◽  
First Moment ◽  
Third Moment

We discuss the moments of the recently measured spin-dependent structure function, [Formula: see text], of the proton. Using the operator product expansion and an effective equation of motion, we show that the third moment can be related to the first moment.

scholarly journals Application of the method of asymptotic homogenization to an acoustic metafluid

2011 ◽  
Vol 467 (2135) ◽  
pp. 3318-3331 ◽  
Author(s):  
John D. Smith
Keyword(s):  
Material Properties ◽  
Effective Properties ◽  
Low Frequency ◽  
Equation Of Motion ◽  
Effective Equation ◽  
Asymptotic Homogenization ◽  
Effective Wave ◽  
Dynamic Effective Properties ◽  
Anisotropic Stiffness ◽  
Natural Way

The method of asymptotic homogenization is used to find the dynamic effective properties of a metamaterial consisting of two alternating layers of fluid, repeating periodically. As well as the effective wave equation, the method gives the effective equation of motion and constitutive relation in a natural way. When the material properties are such that resonant effects can be present in one of the layers, it is found that the metamaterial changes dynamically from a metafluid with anisotropic density and isotropic stiffness at low frequency to one with anisotropic stiffness when the frequency is near to one of the local resonances. In this region of frequency, the resulting metamaterial is not a pentamode material and thus does not belong to the class of metafluids that can be transformed to an isotropic fluid by a coordinate transformation.

scholarly journals Perturbation analysis of the effective equation for two coupled periodically driven oscillators

2006 ◽  
Vol 2006 ◽  
pp. 1-10 ◽  
Author(s):  
Andrzej Okniński ◽  
Jan Kyzioł
Keyword(s):  
Dynamical System ◽  
Perturbation Analysis ◽  
Approximate Equation ◽  
Equation Of Motion ◽  
Internal Motion ◽  
Effective Equation ◽  
Periodically Driven

Dynamics of two coupled periodically driven oscillators is analyzed via approximate effective equation of motion. The internal motion is separated off exactly and then approximate equation of motion is derived. Perturbation analysis of the effective equation is used to study the dynamics of the initial dynamical system.

scholarly journals The Effective Equation of Motion on the Brane World Gravity

2006 ◽  
Vol 38 (1) ◽  
pp. 1-20
Author(s):  
F. P. Zen ◽  
Arianto ◽  
B. E. Gunara ◽  
H. Zainuddin
Keyword(s):  
Equation Of Motion ◽  
Brane World ◽  
Effective Equation

scholarly journals On causal structure of 4D-Einstein–Gauss–Bonnet black hole

2020 ◽  
Vol 80 (9) ◽  
Author(s):  
Naresh Dadhich
Keyword(s):  
Black Hole ◽  
Black Hole Solution ◽  
Causal Structure ◽  
Equation Of Motion ◽  
Cauchy Horizon ◽  
Coupling Constant ◽  
Schwarzschild Black Hole ◽  
Effective Equation ◽  
Central Singularity ◽  
Static Black Hole

AbstractThe recently proposed effective equation of motion for the 4D-Einstein–Gauss–Bonnet gravity admits a static black hole solution that has, like the Rissner–Nordström charged black hole, two horizons instead of one for the Schwarzschild black hole. This means that the central singularity is timelike instead of spacelike. It should though be noted that in $$D\ge 5$$ D ≥ 5 , the solution always admits only one horizon like the Schwarzshild solution. In the equation defining the horizon, the rescaled Gauss–Bonnet coupling constant appears as a new ‘gravitational charge’ with a repulsive effect to cause in addition to event horizon a Cauchy horizon. Thus it radically alters the causal structure of the black hole.

Computer averaging of lattice images of poly-4-methyl-pentene-1 (P4mp1): Noise created artifacts

1987 ◽  
Vol 45 ◽  
pp. 388-389
Author(s):  
P. Pradère ◽  
J.F. Revol ◽  
R. St. John Manley
Keyword(s):  
Low Dose ◽  
Polymer Concentration ◽  
Processing System ◽  
Limiting Factor ◽  
Dilute Solution ◽  
New Techniques ◽  
Dose Unit ◽  
Lattice Images ◽  
Dose Imaging ◽  
Imaging Conditions

Although radiation damage is the limiting factor in HREM of polymers, new techniques based on low dose imaging at low magnification have permitted lattice images to be obtained from very radiation sensitive polymers such as polyethylene (PE). This paper describes the computer averaging of P4MP1 lattice images. P4MP1 is even more sensitive than PE (total end point dose of 27 C m-2 as compared to 100 C m-2 for PE at 120 kV). It does, however, have the advantage of forming flat crystals from dilute solution and no change in d-spacings is observed during irradiation.Crystals of P4MP1 were grown at 60°C in xylene (polymer concentration 0.05%). Electron microscopy was performed with a Philips EM 400 T microscope equipped with a Low Dose Unit and operated at 120 kV. Imaging conditions were the same as already described elsewhere. Enlarged micrographs were digitized and processed with the Spider image processing system.

Two-stage self-seeding method for preparation of single crystals of poly(phenylene sulfide)

1989 ◽  
Vol 47 ◽  
pp. 368-369
Author(s):  
Sengshiu Chung ◽  
Peggy Cebe
Keyword(s):  
Single Crystals ◽  
High Performance ◽  
Dilute Solution ◽  
Two Stage ◽  
Annealing Behavior ◽  
High Performance Polymers ◽  
Seeding Method ◽  
Phenylene Sulfide

We are studying the crystallization and annealing behavior of high performance polymers, like poly(p-pheny1ene sulfide) PPS, and poly-(etheretherketone), PEEK. Our purpose is to determine whether PPS, which is similar in many ways to PEEK, undergoes reorganization during annealing. In an effort to address the issue of reorganization, we are studying solution grown single crystals of PPS as model materials.Observation of solution grown PPS crystals has been reported. Even from dilute solution, embrionic spherulites and aggregates were formed. We observe that these morphologies result when solutions containing uncrystallized polymer are cooled. To obtain samples of uniform single crystals, we have used two-stage self seeding and solution replacement techniques.

Sign in / Sign up

Export Citation Format

Share Document