Statistical Origin of Gravity

Starting from the definition of entropy used in statistical mechanics we show that it is proportional to the gravity action. For a stationary black hole this entropy is expressed as $S = E/ 2T$, where $T$ is the Hawking temperature and $E$ is shown to be the Komar energy. This relation is also compatible with the generalised Smarr formula for mass.Comment: LaTex, 7 pages, no figure, minor clarifications, references added, to appear in Phys. Rev.

Connecting anomaly and tunneling methods for Hawking effect through chirality

The role of chirality is discussed in unifying the anomaly and the tunneling formalisms for deriving the Hawking effect. Using the chirality condition and starting from the familiar form of the trace anomaly, the chiral (gravitational) anomaly, manifested as a nonconservation of the stress tensor, near the horizon of a black hole, is derived. Solution of this equation yields the stress tensor whose asymptotic infinity limit gives the Hawking flux. Finally, use of the same chirality condition in the tunneling formalism gives the Hawking temperature that is compatible with the flux obtained by anomaly method.Comment: LaTex, 8 pages, no figures, reformulation of tunneling mechanism, to appear in Phys. Rev.

Entropy of the Kerr-Sen Black Hole

We study the entropy of Kerr-Sen black hole of heterotic string theory beyond semiclassical approximations. Applying the properties of exact differentials for three variables to the first law thermodynamics we derive the corrections to the entropy of the black hole. The leading (logarithmic) and non leading corrections to the area law are obtained.Comment: 8 pages. Corrected references

Carbon dioxide (CO2) utilizing strain database

Culling of excess carbon dioxide from our environment is one of the major challenges to scientific communities. Many physical, chemical and biological methods have been practiced to overcome this problem. The biological means of CO2 fixation using various microorganisms is gaining importance because database of their substantial role in reversing global warming. Carbon dioxide utilizing strain database (CSD) presents a comprehensive overview of microorganisms involved in biological fixation of carbon dioxide. As a part of this work, the wealth of information on CO2 utilizing strains was first collected and was then managed within four classes, that is, microorganisms, genus listing, mechanisms and literature. The first two classes consolidate information regarding the microbial genus and species, while the later two provide information regarding the CO2 fixing pathways and the taxonomic details of these organisms. The database also holds the current information about the issue. CSD can be used to gain information related to CO2 fixing microbes. It can also contribute to devising biological strategies for reducing carbon dioxide from the environment. It introduces an innovative idea of exploring the potential of these bacterial strains for reversing global warming. The CSD can be accessed at http://csd.igib.res.in.Key words: Carbon dioxide utilizing strain database (CSD), carbon dioxide, autotrophic microorganisms, global warming, biological fixation of CO2, CO2 fixing pathways

Thermalization of horizon through asymptotic symmetry in three-dimensional massive gravity

Recently, black hole symmetries have been studied widely and it has been speculated that this procedure will lead to the deeper understanding of the black hole physics. Spontaneous symmetry breaking of the horizon symmetries is one of the very recent attempt to clarify black hole thermal physics. In this work, we are going to investigate the same in three dimensional massive gravity, including higher order of Riemann tensor. We observe that the idea also works well in this gravitational theory, thereby providing stronger demand of the viability of this idea.Comment: 17 Page

CONSTRAINT ROBUST PORTFOLIO SELECTION BY MULTIOBJECTIVE EVOLUTIONARY GENETIC ALGORITHM

The problem of portfolio selection is a very challenging problem in computational finance and has received a lot of attention in last few decades. Selecting an asset and optimal weighting of it from a set of available assets is a critical issue for which the decision maker takes several aspects into consideration. Different constraints like cardinality constraints, minimum buy in thresholds and maximum limit constraint are associated with assets selection. Financial returns associated are often strongly non-Gaussian in character, and exhibit multivariate outliers. Taking these constraints into consideration and with the presence of these outliers we consider a multi-objective problem where the percentage of each available asset is so selected that the total profit of the portfolio is maximized while total risk is minimized. Nondominated Sorting Genetic Algorithm-II is used for solving this multiobjective portfolio selection problem. Performance of the proposed algorithm is carried out by performing different numerical experiments using real-world data

BioRadBase: A database for bioremediation of radioactive waste

Radioactive waste from different sectors such as nuclear energy, health care and food has become a discernible part of our environment. Several dumping methods are in routine practice to dispose radioactive wastes. Huge chemical and energy input in various skillful physico-chemical methods has limited their use while biological methods exploring the potential of micro-organisms could be a promising and eco-friendly approach to remediate radioactive pollutants. Bio-transformation, bio-accumulation and bio-sorption are key processes that have been tried for radionuclide remediation. BioRaDBase is the first database dedicated to micro-organisms which have been explored or engineered to remediate radioactive waste from the environment. The database serves as a comprehensive knowledgebase to search bacteria and fungi which have the ability to transform radioactive waste. This database would be a useful tool for the development of new bio-remediation technologies to clean up radioactive waste from the environment. The information in database has been managed under five classes, that is, type of radioactive waste, micro-organisms, genus listing, literature and waste management. The entries are also linked to external databases such as National Center for Biotechnology Information (NCBI), providing wide background information. Beside these, under the news section of the database, a user can connect to dedicated organizations working on issues like environmental protection, nuclear energy and radionuclide dumping. BioRaDBase can be accessed at http://biorad.igib.res.in.Keywords: Bioremediation of radioactive waste (BioRaDBase), radionuclides, biotransformation, biocrystallization, radioisotope, nuclear wast

Hamilton-Jacobi Tunneling Method for Dynamical Horizons in Different Coordinate Gauges

Previous work on dynamical black hole instability is further elucidated within the Hamilton-Jacobi method for horizon tunneling and the reconstruction of the classical action by means of the null-expansion method. Everything is based on two natural requirements, namely that the tunneling rate is an observable and therefore it must be based on invariantly defined quantities, and that coordinate systems which do not cover the horizon should not be admitted. These simple observations can help to clarify some ambiguities, like the doubling of the temperature occurring in the static case when using singular coordinates, and the role, if any, of the temporal contribution of the action to the emission rate. The formalism is also applied to FRW cosmological models, where it is observed that it predicts the positivity of the temperature naturally, without further assumptions on the sign of the energy.Comment: Standard Latex document, typos corrected, refined discussion of tunneling picture, subsection 5.1 remove