We present distance measurements to 71 high redshift type Ia supernovae discovered during the first year of the 5-year Supernova Legacy Survey (SNLS). These events were detected and their multi-color light-curves measured using the MegaPrime/MegaCam instrument at the Canada-France-Hawaii Telescope (CFHT), by repeatedly imaging four one-square degree fields in four bands. Follow-up spectroscopy was performed at the VLT, Gemini and Keck telescopes to confirm the nature of the supernovae and to measure their redshift. With this data set, we have built a Hubble diagram extending to z = 1, with all distance measurements involving at least two bands. Systematic uncertainties are evaluated making use of the multiband photometry obtained at CFHT. Cosmological fits to this first year SNLS Hubble diagram give the following results: {Omega}{sub M} = 0.263 {+-} 0.042 (stat) {+-} 0.032 (sys) for a flat {Lambda}CDM model; and w = -1.023 {+-} 0.090 (stat) {+-} 0.054 (sys) for a flat cosmology with constant equation of state w when combined with the constraint from the recent Sloan Digital Sky Survey measurement of baryon acoustic oscillations.

The Supernova Legacy Survey: Measurement of Omega_m, Omega_l and w from the First Year Data Set

The main purpos e of this chapter is to present a direct and systematic way of finding exact solutions and Backlund transformations of a certain class of nonlinear evolution equations. The nonlinear evolution equations are transformed, by changing the dependent variable(s), into bilinear differential equations of the following special form 
 
$$ F\left( {\frac{\partial }{{\partial t}} - \frac{\partial }{{\partial {t^1}}},\frac{\partial }{{\partial x}} - \frac{\partial }{{\partial {x^1}}}} \right)f(t,x)f({t^1},{x^1}){|_{t = {t^1},x = {x^1}}} = 0 $$ 
 
, which we solve exactly using a kind of perturbational approach.

Direct Methods in Soliton Theory (非線形現象の取扱いとその物理的課題に関する研究会報告)

To find more deliberate f ( R , T ) cosmological solutions, we take our previous paper further by studying some new aspects of the considered models via investigation of some new cosmological parameters/quantities to attain the most acceptable cosmological results. Our investigations are performed by applying the dynamical system approach. We obtain the cosmological parameters/quantities in terms of some defined dimensionless parameters that are used in constructing the dynamical equations of motion. The investigated parameters/quantities are the evolution of the Hubble parameter and its inverse, the “weight function”; the ratio of the matter density to the dark energy density and its time variation; the deceleration; the jerk and the snap parameters; and the equation-of-state parameter of the dark energy. We numerically examine these quantities for two general models R + α R - n + - T and R log [ α R ] q + - T . All considered models have some inconsistent quantities (with respect to the available observational data), except the model with n = - 0.9 , which has more consistent quantities than the other ones. By considering the ratio of the matter density to the dark energy density, we find that the coincidence problem does not refer to a unique cosmological event; rather, this coincidence also occurred in the early Universe. We also present the cosmological solutions for an interesting model R + c 1 - T in the nonflat Friedmann–Lemaitre–Robertson–Walker metric. We show that this model has an attractor solution for the late times, though with w ( DE ) = - 1 / 2 . This model indicates that the spatial curvature density parameter gets negligible values until the present era, in which it acquires the values of the order 10 - 4 or 10 - 3 . As the second part of this work, we consider the weak-field limit of f ( R , T ) gravity models outside a spherical mass immersed in the cosmological fluid. We have found that the corresponding field equations depend on the both background values of the Ricci scalar and the background cosmological fluid density. As a result, we attain the parametrized post-Newtonian parameter for f ( R , T ) gravity and show that this theory can admit the experimentally acceptable values of this parameter. As a sample, we present the post-Newtonian gamma parameter for general minimal power law models, in particular, the model R + c 1 - T .

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Cosmological and Solar System Consequences of f(R,T) Gravity Models

We investigate the cosmological solutions of $f(R,T)$ modified theories of gravity for a perfect fluid in a spatially Friedmann-Lema\^{\i}tre-Robertson-Walker metric through the phase-space analysis, where $R$ is the Ricci scalar and $T$ denotes the trace of the energy-momentum tensor of the matter content. We explore and analyze the three general theories with the Lagrangians of minimal $g(R)+h(T)$, pure nonminimal $g(R)h(T)$, and nonminimal $g(R)(1+h(T))$ couplings through the dynamical systems approach. We introduce a few variables and dimensionless parameters to simplify the equations to more concise forms. The conservation of the energy-momentum tensor leads to a constraint equation that, in the minimal gravity, confines the functionality of $h(T)$ to a particular form, and hence relates the dynamical variables. In this case, acceptable cosmological solutions that contain a long enough matter-dominated era followed by a late-time accelerated expansion are found. To support the theoretical results, we also obtain numerical solutions for a few functions of $g(R)$, and the results of the corresponding models confirm the predictions. We separate the solutions into six classes which demonstrate more acceptable solutions and there is more freedom to have the matter-dominated era than in $f(R)$ gravity. In particular, there is a new fixed point which can represent the late-time acceleration. We draw different diagrams of the matter densities (consistent with the present values), the related scale factors, and the effective equation of state. The corresponding diagrams of the parameters illustrate that there is a saddle acceleration era which is a middle era before the final stable-acceleration de Sitter era for some models. All presented diagrams determine radiation, matter, and late-time acceleration eras very well. The pure nonminimal theory suffers from the absence of a standard matter era, though we illustrate that the nonminimal theory can have acceptable cosmological solutions.

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f ( R , T ) cosmological models in phase space

This paper is devoted to study the possibility of forming anisotropic compact stars in modified Gauss–Bonnet, namely called as f(G) theory of gravity which is one of the strong candidates, responsible for the accelerated expansion of the universe. For this purpose, we have used analytical solution of Krori and Barua metric to the Einstein field equations with anisotropic form of matter and power law model of f(G) gravity. To determine the unknown constants in Krori and Barua metric, we have used the sample of compact stars, 4U1820-30, Her X-1, SAX J 1808-3658. The physical behavior of these stars have been analyzed with the observational data. In this setting, we have checked all the regularity conditions and stability of the compact stars 4U1820-30, Her X-1, SAX J 1808-3658.

Anisotropic compact stars in f(G) gravity

In this article, we explore solitary wave structures in nonlinear negative-index materials with beta and M-truncated fractional derivatives with the existence of a Bohm potential. The consideration of Bohm potential produced quantum phase behavior in electromagnetic waves. The applied technique is the New extended algebraic method. By use of this approach, acquired solutions convey various types of new families containing dark, dark-singular, dark-bright, and singular solutions of Type 1 and 2. Moreover, the constraint conditions for the presence of the obtained solutions are a side-effect of this technique. Finally, graphical structures are depicted.

Optical Solitons with Beta and M-Truncated Derivatives in Nonlinear Negative-Index Materials with Bohm Potential.

Conserved quantities for (1+2)-dimensional non-linear wave equation on curved surfaces

Petrov Type D-Levi-Civita (DLC) space-time is considered in two different coordinates, that is, spherical and cylindrical. Noether gauge symmetries and their corresponding conserved quantities for respective metric with the restricted range of parameters and coordinates are discussed.

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Noether Gauge Symmetries for Petrov Type D-Levi-Civita Space-Time in Spherical and Cylindrical Coordinates

The new extended direct algebraic technique is used to attain the new exact solitary wave solutions of the nonlinear fractional couple Drinfeld–Sokolov–Wilson system (DSWS). This DSWS has a lot of applications in water waves, fluid mechanics, quantum mechanics, chemistry, and biology. This system is developed in the perspective of fractional theory of calculus, for this purpose Riemann–Liouville fractional derivative (RLFD), [Formula: see text]-fractional differential operator and Atangana–Baleanu fractional derivative (ABFD) are utilized. The attained solutions contain some new families such as trigonometric functions, hyperbolic functions, rational functions, logarithmic functions, and exponential functions. The graphically analysis and comparison of solutions are plotted by taking appropriate values of the constant parameters to enhance the understanding of physical real-life phenomena. The approach is said to be compatible and effective as a scientific approach for the examination of the various spacetime fractional models in engineering and physics concerning real-life issues. 

The comparative report on dynamical analysis about fractional non-linear Drinfeld-Sokolov-Wilson system

Physical models with non-flat background are important in biological mathematics. Most of the biological membranes are not flat in general. For example, membranes which convert energy in mitochondria and chloroplasts are tubes, buds and may be sheets. In most of the biological processes, the geometry of membranes is very important. The organization and shape of the membranes play a vital role in biological processes such as shape change, fusiondivision, ion adsorption etc. A cell membrane is a system for exchange of energy and matter from the neighbourhood. Absorption and transformation of conserved quantities such as energy and matter from the environment are one of the characteristics of membranes. The shape of proteins, non zero curvature of membranes and involvement of conserved quantities lead one to discuss physical models on curved surfaces. Conservation laws play a vital role in science and also helpful to construct potential systems which can be used to calculate exact solutions of differential equations. Physical models on curved surfaces govern partial differential equation which need not to be derivable from variational principle. The partial Noether approach is the systematic way to construct the conservation laws for non-variational problems. The group classification and conservation laws for some partial differential equation on curved surfaces are presented in this dissertation. In particular some linear and nonlinear models of heat and wave equation on plane, cone, sphere are classified. The conservation laws for the (1 + 2)-dimensional heat equation on different surfaces are constructed via partial Noether approach and then the results are generalized for the (1+n)-dimensional case. The symmetry conservation laws relation is used to simplify the derived conserved vectors and exact solutions are constructed. We also extend these results to a special type of (1 + n)-dimensional v linear evolution equation. Potential systems of some models from different sciences are also given. The similar analysis is performed for the (1 + 2)-dimensional wave equation on the sphere, cone and on flat surface. Furthermore, the nonlinear heat equation on curved surfaces is considered. A class of functions is found on the plane, sphere and torus, which is not only independent of the number of independent variables but also independent of the background metric. We consider whether the background metric or the nonlinearity have the dominant role in the infinitesimal generators of heat equation on curved manifolds. Then a complete Lie analysis of the time dependent Ginzburg-Landau equation (TDGL model) is presented on the sphere and torus. In addition, for the (1+n)-dimensional nonlinear wave equation (Klein Gordon Equation) it is proved that there is a class of functions which is independent from number of independent variables. Then for the (1 + 2)-dimensional wave equation it is proved that there is a class of functions which is invariant either the underlying space is a plane, sphere or torus.

Adil Jhangeer

Papers

Optical Solitons with Beta and M-Truncated Derivatives in Nonlinear Negative-Index Materials with Bohm Potential.

Conserved quantities for (1+2)-dimensional non-linear wave equation on curved surfaces

Noether Gauge Symmetries for Petrov Type D-Levi-Civita Space-Time in Spherical and Cylindrical Coordinates

The comparative report on dynamical analysis about fractional non-linear Drinfeld-Sokolov-Wilson system

Symmetry Analysis and Conservation Laws: Of Physical Models on Curved Surfaces