Godel Type Metrics in Randall Sundrum Model

Anisotropic cosmological models such as the G\"{o}del universe and its extensions - G\"{o}del type solutions, are embedded on a visible 3-brane in the Randall-Sundrum 1 model. The size of the extra dimension is stabilized by tuning the rotation parameter to a very small value so that hierarchy problem can be solved. A limiting case also yields the Randall-Sundrum 2 model. The rotation parameter on the visible brane turns out to be of order $10^{-32}$, which implies that visible brane essentially lacks rotation.Comment: 10 pages, typos corrected and references adde

Scale Invariance as a Solution to the Cosmological Constant Problem

We show that scale invariance provides a solution to the fine tuning problem of the cosmological constant. We construct a generalization of the standard model of particle physics which displays exact quantum scale invariance. The matter action is invariant under global scale transformations in arbitrary dimensions. However the gravitational action breaks scale invariance explicitly. The scale symmetry is broken spontaneously in the matter sector of the theory. We show that the contribution to the vacuum energy and hence the cosmological constant is identically zero from the matter sector within the full quantum theory. However the gravitational sector may give non-zero contributions to the cosmological constant at loop orders. No fine tuning may be required at loop orders since the matter sector gives zero contribution to the cosmological constant. We also show that we do not require full scale invariance in order to constrain the vacuum energy from the matter sector. We only require invariance under pseudoscale transformations. Using this idea and motivated by the concept of unimodular gravity we propose an alternative model. In this case also we show that matter sector gives exactly zero contribution to the vacuum energy.Comment: 12 pages, no figure

A fluid dynamic analysis of the blast furnace trough at Tata Steel

The non-drainable trough of 'F' blast furnace at Tata Steel has been fluid dynamically simulated by solving the Navier-Stokes equation in order to predict the velocity field near the trough bed along with other field properties so as to focus on the locations of surface wear on the trough bed. For this purpose a total length of 3.64 m, the mast wear prone zone, of the entire trough has been taken in to considerations for modeling. The modeling zone or the computational domain consists of the skimmer plate, iron dam and some portion of the runner. The modeled portion of the trough has always higher wear compared to other locations on the trough so a fluid dynamic analysis has been done for the liquid metal in this particular portion of the trough. Turbulence present in the velocity field has been taken into considerations by imbedding the K-e turbulent model to the parent differential equations for the velocity field. The entire set of partial differ-ential equations (two for the velocities, one for contin-uity and one each for the turbulent quantities k and e) have been solved by employing a strongly non-uniform stagg-ered grid through Phoenics. The predicted velocity field reveals a strong recirculation zone just behind the skimmer plate and comparatively high shear stress just after the iron dam (at the beginning of the runner). The inclination of the iron dam has been-varied starting from 90° to 35°. It has been observed that for a 35° iron dam the predicted maximum shear stress on the trough bed has a much lower value than that of the 90° iron dam. From this analysis it has been concluded that the value of the maximum shear stress on the trough bed is an important parameter contributing to the amount of refractory wear and the location of the maximum shear stress signifies the weakest zone on the trough bed which is vulnerable to wear caused by fluid shear. It has also been noticed that the present analysis has offered many qualitative trends which are in agreement with the plant observations

Cosmological Perturbation Analysis in a Scale Invariant Model of Gravity

We consider a model for gravity that is invariant under global scale transformations. It includes one extra real scalar field coupled non-minimally to the gravity fields. In this model all the dimensionful parameters like the gravitational constant and the cosmological constant etc. are generated by a solution of the classical equations of motion which breaks scale invariance. In this paper we demonstrate the stability of such a solution against small perturbations in a flat FRW background by making a perturbative expansion around this solution and solving the resulting equations linear in the perturbations.Comment: 9 pages, 1 figur

Can Blended Learning Address Indian Academic Issues?

Over the years, India has implemented social reforms aimed at providing education to all. This is observed from the growth in GER (Gross Enrollment Ratio) over the years that has resulted in a decrease in the number of students absent in schools. Coronavirus, nonetheless, has disturbed this scenario and is testing the functions, efficiencies, and practices of India\u27s schooling framework. This research paper, written for stakeholders in government, and the education sector, anticipate the extent to which there is a need of continuing the imparting of education. The main objective of this paper is to provide an overview of the newer ways that may help continue the process of learning and teaching amidst this lockdown situation that is prevailing across the world. This disruption of education has forced pushed the policymakers to consider another way of imparting quality education (both primary and secondary). This has resulted in the use of a ‘blended (mixed) learning methodology’ that incorporates one-to-one learning (classroom) as well as one-to-many (e-learning). In this context, the authors would like to emphasize the need of strengthening the basic education framework that imparts education to all

Comparative evaluation of effects of combined oral anti-diabetic drugs (sulfonylurea plus pioglitazone and sulfonylurea plus metformin) over lipid parameters in type 2 diabetic patients

Background: Type 2 diabetes is associated with significant cardiovascular morbidity and mortality. Dyslipidemia, which affects almost 50% of patients with type 2 diabetes, is a cardiovascular risk factor characterized by elevated triglyceride levels, low high-density lipoprotein (HDL) cholesterol levels, and a preponderance of small, dense, low-density lipoprotein (LDL) particles. In addition to their glucose-lowering properties, oral anti-diabetic agents may have effects on lipid levels, especially triglycerides (TGs), HDL-C, LDL-C and total cholesterol levels.Methods: A prospective, open-labeled, randomized, parallel-group study was carried out in sizable number of patients (n=40) of established type 2 diabetes on combined oral anti-diabetic drugs, to investigate the effects of combined oral anti-diabetic on lipid parameters who was not receiving any hypolipidemic agent in addition.Results: Statistically significant mean reduction of triglycerides (TGs) of 25.1mg/dl (a 15.30% reduction from baseline value) and by 13.5 mg/dl (a 8.94% reduction from baseline value) in the SU (sulfonylurea) plus PIO (pioglitazone) and SU plus MET (metformin) group respectively. Present study also shows improvement in HDL cholesterol with SU plus PIO group by 13.18% which is almost twice that observed in SU plus MET group (8.06%). Present study also shows increase in LDL cholesterol with SU plus PIO group by 2.10%, is just opposite to SU plus MET group (4.92 % decrease). With SU plus PIO group, a statistically significant mean reduction of total cholesterol (TC) of 8.33mg/dl (5.14 % decrease) and by 7.62 mg/dl (4.28% decrease) in the SU plus MET group.Conclusions: Pioglitazone, a thiazolidinedione, has been shown to improve the lipid profile in patients with type 2 diabetes by increasing HDL-C levels and by decreasing triglyceride and total cholesterol levels in monotherapy or combination regimens with sulfonylurea. Metformin also has been shown to reduce LDL-C, TC, and TG levels and increase HDL-C levels in monotherapy and in combination regimens with sulfonylurea. In contrast, LDL cholesterol levels mild increase with pioglitazone monotherapy or with SU combination therapy. Thus the results of this study have demonstrated that SU plus pioglitazone is an effective combination regimen for patients insufficiently treated with SU monotherapy and may provide possible positive effects on other coronary risk factors/ dyslipidemias associated with the type 2 diabetes

Can Blended Learning Address Indian Academic Issues?

Over the years, India has implemented social reforms aimed at providing education to all. This is observed from the growth in GER (Gross Enrollment Ratio) over the years that has resulted in a decrease in the number of students absent in schools. Coronavirus, nonetheless, has disturbed this scenario and is testing the functions, efficiencies, and practices of India\u27s schooling framework. This research paper, written for stakeholders in government, and the education sector, anticipate the extent to which there is a need of continuing the imparting of education. The main objective of this paper is to provide an overview of the newer ways that may help continue the process of learning and teaching amidst this lockdown situation that is prevailing across the world. This disruption of education has forced pushed the policymakers to consider another way of imparting quality education (both primary and secondary). This has resulted in the use of a ‘blended (mixed) learning methodology’ that incorporates one-to-one learning (classroom) as well as one-to-many (e-learning). In this context, the authors would like to emphasize the need of strengthening the basic education framework that imparts education to all