Black Hole with Quantum Potential

In this work, we investigate black hole (BH) physics in the context of quantum corrections. These quantum corrections were introduced recently by replacing classical geodesics with quantal (Bohmian) trajectories and hence form a quantum Raychaudhuri equation (QRE). From the QRE, we derive a modified Schwarzschild metric, and use that metric to investigate BH singularity and thermodynamics. We find that these quantum corrections change the picture of Hawking radiation greatly when the size of BH approaches the Planck scale. They prevent the BH from total evaporation, predicting the existence of a quantum BH remnant, which may introduce a possible resolution for the catastrophic behavior of Hawking radiation as the BH mass approaches zero. Those corrections also turn the spacelike singularity of the black hole to be timelike, and hence this may ameliorate the information loss problem.Comment: 16 pages, 6 figures; Accepted in Nucl.Phys.

A Proposal for Testing Gravity's Rainbow

Various approaches to quantum gravity such as string theory, loop quantum gravity and Horava-Lifshitz gravity predict modifications of the energy-momentum dispersion relation. Magueijo and Smolin incorporated the modified dispersion relation (MDR) with the general theory of relativity to yield a theory of gravity's rainbow. In this paper, we investigate the Schwarzschild metric in the context of gravity's rainbow. We investigate rainbow functions from three known modified dispersion relations that were introduced by Amelino-Camelia, et el. in [arXiv:hep-th/9605211, arXiv:0806.0339v2, arXiv:astro-ph/9712103] and by Magueijo-Smolin in [arXiv:hep-th/0112090]. We study the effect of the rainbow functions on the deflection of light, photon time delay, gravitational red-shift, and the weak equivalence principle. We compare our results with experiments to obtain upper bounds on the parameters of the rainbow functions.Comment: 6 pages, no figures, to appear in Europhysics Letter

Remnant for all Black Objects due to Gravity's Rainbow

We argue that a remnant is formed for all black objects in gravity's rainbow. This will be based on the observation that a remnant depends critically on the structure of the rainbow functions, and this dependence is a model independent phenomena. We thus propose general relations for the modified temperature and entropy of all black objects in gravity's rainbow. We explicitly check this to be the case for Kerr, Kerr-Newman-dS, charged-AdS, and higher dimensional Kerr-AdS black holes. We also try to argue that a remnant should form for black Saturn in gravity's rainbow. This work extends our previous results on remnants of Schwarzschild black holes [ arXiv:1402.5320] and black rings [arXiv:1409.5745].Comment: 21 pages, 13 figures, Accepted in Nucl.Phys.

Remnants of Black Rings from Gravity's Rainbow

In this paper, we investigate a spinning black ring and a charged black ring in the context of gravity's rainbow. By incorporating rainbow functions proposed by Amelino-Camelia, et al. in [arXiv:hep-th/9605211, arXiv:0806.0339v2] in the metric of the black rings, a considerable modification happens to their thermodynamical properties. We calculate corrections to the temperature, entropy and heat capacity of the black rings. These calculations demonstrate that the behavior of Hawking radiation changes considerably near the Planck scale in gravity's rainbow, where it is shown that black rings do not evaporate completely and a remnant is left as the black rings evaporate down to Planck scale.Comment: 14 pages, 6 figure

Assessment The Agricultural Student's Attitudes Towards Organic Farming (Case of Iran)

A surveying research was conducted to study and recognize the knowledge and attitude of students toward organic farming at three universities of Iran in 2010. Our consumption patterns and environmental behaviors are rooted in long lived practices and habits. Social norms and values are among the factors that determine what we buy or what we think about organic products. As they are largely unconscious it is difficult to change them. Students are the agriculturist of tomorrow; therefore policies aimed at developing organic farming should address the needs of this group. To discover agriculturist's knowledge organic farming, a survey among 100 agricultural students was conducted. Questionnaire was used to examine students’ knowledge regarding organic farming. Finding is shown that agriculturist's awareness towards organic farming are low, especially in Pests management and Organic product standards aspect. The result of factor analysis showed that nine factors named as concepts, Nutrient safety and security, Organic farming economic, Organic farming extension, Social issue, fertility, Pests management, Environment safety, Organic product standard explained 73.71% of total variance that the first factor accounts for 11.98% of the variance, the second 10.954%, the third 9.191%, the fourth 8.505%, the fifth 8.426%, the sixth 7.536%, the seventh 7.015%, the eighth 5.746% and the ninth 4.364%. In conclusion, to enhance student knowledge about organic farming, it is important that curriculum develops for familiar student with organic farming practices and concepts such as: ecological equilibrium, agro ecosystem sustainability, new technology and indigenous knowledge, nutrition value, human safety, favorite yield production, soil structure improvement, erosion reduces and etc

THE CHALLENGES OF SUSTAINABLE HISTORICAL CENTERS: THE CASE OF ROSETTE, EGYPT

Historical centers of many Egyptian cities managed to survive as living cities in spite of physical decline and economic depression. Their fabric carries out the spiritual and cultural messages that communicate with their present citizens. The heritage of these historic city centers are not only Material character, but much more. Generally, the conservation of historic centers is fundamentally different from conservation of single monument. While a single monument can be kept on a chosen state of evolution, the historic centers cannot be preserved in particular state \u201cwith exception of the small areas conserved for tourist purposes\u201d. The historic centers, as living cities must meet the varying needs of citizens with sustainable transformations. The challenge is not how to preserve, but how to create dynamic living spaces and places that produce rich in cultural traditions that lead organically from the past to the future. The research will study and analyze the historical center of \u201cRosetta\u201d, which is one of the intermediate cities in northern Egypt that has a particular architectural heritage and many urban problems. The city of Rosetta (Rashid in Arabic) is located on the west bank of the Rosetta branch of the Nile, approximately 65km east of Alexandria on the Mediterranean coast. Today it is best known for the Rosetta stone, which was discovered in the Qayitbay castle in 1799. The city history passed over many periods of increase and decrease in its importance due to economical and political reasons. Its architectural heritage reveals the influence of various ages, but the most unique are merchant houses and mosques from the ottoman period. The city also has a particular suburban landscape of agricultural land and palm groves that are of great importance. Although Rosetta is no longer a leading commercial center, its citizens are employed in various typical activities, which are mainly agriculture, stocking and processing rice from the Delta, fishing and building ships and yachts. The main problem that faces the historic buildings of Rosetta is moisture from the soil, caused by an excess of underground salt water. The historic merchant houses have been the subject of many restoration projects over the past 20 years, but many of them have regularly been re-damaged by water and humidity and are currently under re-restoration. Unfortunately, some have even collapsed or were demolished. However, there are a number of activities that may take place in the historic buildings no longer used, maintaining the characteristics, such as crafts centers, libraries and cultural places that serve the local communities. Rosetta's historic center future must include renovation and modernization of basic infrastructure and development of traditional production sectors, based on the exploitation of this natural and cultural heritage to promote tourism locally and internationally. Physical restoration of the buildings is not enough to keep the historic center of the city alive, but a project for rehabilitation based on sustainability should be initiated. Not only to preserve and restore the outer shell, but inside the shell should insert some activities, social and economic dynamics that can make best use of resources and potential. The revitalization of Rosetta provides a mix of cultural, social, economic, technical and institutional that needs coordinated investments by the government. Must involve residents, landowners and all those have interest to ensure the careful maintenance and replacement of the elements of the built environment. This does not only depend on the availability of funding but also the specific technical and social skills that make up the traditional know-how. Unfortunately, many historical cities, especially the intermediate cities in Egypt suffer from lack of funds and local expertise. But the main problem is the lack of cooperation between the authorities who make the decisions

Absence of Black Holes at LHC due to Gravity's Rainbow

In this paper, we investigate the effect of Planckian deformation of quantum gravity on the production of black holes at colliders using the framework of gravity's rainbow. We demonstrate that a black hole remnant exists for Schwarzschild black holes in higher dimensions using gravity's rainbow. The mass of this remnant is found to be greater than the energy scale at which experiments were performed at the LHC. We propose this as a possible explanation for the absence of black holes at the LHC. Furthermore, we demonstrate that it is possible for black holes in six (and higher) dimensions to be produced at energy scales that will be accessible in the near future.Comment: 16 pages, 5 figures, to appear in Phys. Lett.

On supersymmetric contributions to the CP asymmetry of the B -> phi K_S

We analyse the CP asymmetry of the B -> phi K_S process in general supersymmetric models. In the framework of the mass insertion approximation, we derive model independent limits for the mixing CP asymmetry. We show that chromomagnetic type of operator may play an important role in accounting for the deviation of the mixing CP asymmetry between B -> phi K_S and B -> J/psi K_S processes observed by Belle and BaBar experiments. A possible correlation between the direct and mixing CP asymmetry is also discussed. Finally, we apply our result in minimal supergravity model and supersymmetric models with non-universal soft terms.Comment: 19 pages, 3 figure