Planck-Scale Corrections to Friedmann Equation

Recently, Verlinde proposed that gravity is an emergent phenomenon which originates from an entropic force. In this work, we extend Verlinde's proposal to accommodate generalized uncertainty principles (GUP), which are suggested by some approaches to \emph{quantum gravity} such as string theory, black hole physics and doubly special relativity (DSR). Using Verlinde's proposal and two known models of GUPs, we obtain modifications to Newton's law of gravitation as well as the Friedmann equation. Our modification to the Friedmann equation includes higher powers of the Hubble parameter which is used to obtain a corresponding Raychaudhuri equation. Solving this equation, we obtain a leading Planck-scale correction to Friedmann-Robertson-Walker (FRW) solutions for the $p=\omega \rho$ equation of state.Comment: 15 pages, no figure, to appear in Central Eur.J.Phys. arXiv admin note: text overlap with arXiv:1301.350

Minimal Length, Friedmann Equations and Maximum Density

Inspired by Jacobson's thermodynamic approach[gr-qc/9504004], Cai et al [hep-th/0501055,hep-th/0609128] have shown the emergence of Friedmann equations from the first law of thermodynamics. We extend Akbar--Cai derivation [hep-th/0609128] of Friedmann equations to accommodate a general entropy-area law. Studying the resulted Friedmann equations using a specific entropy-area law, which is motivated by the generalized uncertainty principle (GUP), reveals the existence of a maximum energy density closed to Planck density. Allowing for a general continuous pressure $p(\rho,a)$ leads to bounded curvature invariants and a general nonsingular evolution. In this case, the maximum energy density is reached in a finite time and there is no cosmological evolution beyond this point which leaves the big bang singularity inaccessible from a spacetime prospective. The existence of maximum energy density and a general nonsingular evolution is independent of the equation of state and the spacial curvature $k$. As an example we study the evolution of the equation of state $p=\omega \rho$ through its phase-space diagram to show the existence of a maximum energy which is reachable in a finite time.Comment: 15 pages, 1 figure, minor revisions, To appear in JHE

Socially Responsible Investing interconnect with the Supply Chain Management in Islamic Finance Model

The concept of Islamic finance is related to Socially Responsible Investment (SRI) by many researchers in different time frames based on the similarities between Islamic finance and the concept of SRI and Supply Chain Management (SCM). SRI has been described by many authors as an investment philosophy that includes non-financial, ethical (e.g., social and environmental) objectives. This paper will shed the light on the interconnection between concepts the Socially Responsible Investment (SRI) and the Islamic Finance Model (IFM). To explain and explore the concept of SRI within Islamic Finance qualitative research technique will be used.  The findings show that central values in IFM and SRI could be matched to optimize prospects for Islamic finance to tap the large pool of global SRI funds. Moving forward, greater interplay between these two markets should be explored. Key stakeholders on both ends, including financial experts, research centers, rating agencies, non-governmental organizations and even regulators should pursue ways to consolidate the connectivity of these markets. The Islamic finance focuses mainly on risk sharing, individuals’ rights and responsibilities, property rights and the purity of contracts. Receipt and payment of interest in contracts differentiate Islamic Finance from conventional finance. The other factors such as banned on contracts involving investments in alcohol, tobacco, drugs, pornography, prostitution, gambling, armaments, animal experimentation, genetic engineering, financial exploitation makes it similar to social responsible investment SRI

Removal Of Colour And Organic Pollutants From Textile Wastewater Using Integrated Biological And Advanced Oxidation Process

Textile industrial wastewater effluent varies greatly in characteristics within a plant and even from the same process from time to time. Removal of pollutants such as colour and organics by conventional techniques has been difficult and could not reach the level of required discharge. In this study, colour and organic removals from textile wastewater in a continuous process using an integrated system of activated sludge and advanced oxidation process was studied. The primary objective was to reduce colour to 50 PtCo; the total organic carbon (TOC), chemical oxygen demand (COD), biochemical oxygen demand (BOD), and total suspended solid (TSS) to less than 20, 50, 20 and 20 mg/l, respectively; and to remove oil and grease (O&G). Activated sludge was satisfactory in terms of removing TOC, COD, BOD, O&G and TSS. At 36 h retention time, the removal of TOC, COD, BOD, O&G and TSS were 80, 78, 79, 53 and 61%, respectively. However, the colour removal was only 37%. With equalization tank, combining of 50 mg/l O3 with 1 ml/l H2O2 and UV was proven capable of reducing the colour, TOC, COD, BOD, O&G and TSS after 60 min by 97, 60, 64, 62, 90 and 36%, respectively. Without equalization tank, activated sludge treatment was efficient in terms of removing TOC, COD, BOD, O&G and TSS from the different strengths of textile wastewater samples. Removals of TOC, COD, BOD, O&G and TSS were 76-86, 77-84, 78-82, 34-61 and 65-74%, respectively. However, colour removal was from 17 to 34%. This means that activated sludge was satisfactory in removing only organics pollutants. Having different, easy control and successful processes that treat different strengths of textile wastewater is the best formulation of process treatment options to ensure appreciable removals of colour and organic pollutants from any strength of textile wastewater. A software called TexTreat was successfully developed. It can determine the required process treatment option of AOPs for any existing textile treatment plant and predict the characteristics of the final discharge using different retention times. The validation of the process treatment options using TexTreat shows their applicability with different textile wastewater plants

European Union foreign policy towards Egypt during the Arab spring of 2011

With the onset of the Arab Spring, external actors found themselves caught off guard by the democratic uprisings and the implications they hold to their respective national interests in the region. For the EU, the instability in the region presents challenges to the long relationship the European nations culminated with the Middle East, especially with Egypt. The uprising created a situation where the EU had to develop new policies to capitalize on the opportunity for democratic change while maintaining the decades long EU’s interest in Egypt. Accordingly, the main question this study tries to answer is whether and the extent to which the EU was able to adopt the proper policies, particularly whether the EU was able to use the resources at its disposal to facilitate democratic change in Egypt. The following secondary questions would also be answered throughout the study: 1. What is the nature of the EU’s foreign policy in terms of its mechanism, limitations, major premises and factors influencing its effectiveness? 2. What is the history of EU-Egyptian partnership prior to the Arab Spring? 3. Where there any changes to EU-Egyptian relations after the Arab Spring to the present? 4. How does the situation of Tunisia and the EU’s actions in the country differ from the EU’s actions in the Egyptian case

Enabling Solutions for Integration and Interconnectivity in Millimeter-wave and Terahertz Systems

Recently, Terahertz (THz) systems have witnessed increasing attention due to the continuous need for high data rate transmission which is mainly driven by next-generation telecommunication and imaging systems. In that regard, the THz range emerged as a potential domain suitable for realizing such systems by providing a wide bandwidth capable of achieving and meeting the market requirements. However, the realization of such systems faces many challenges, one of which is interconnectivity and high level of integration. Conventional packaging techniques would not be suitable from performance perspective above 100 GHz and new approaches need to be developed. This thesis proposes and demonstrates several approaches to implement interconnects that operate above 100 GHz. One of the most attractive techniques discussed in this work is to implement on-chip coupling structures and insert the monolithic microwave integrated circuit (MMIC) directly into a waveguide (WG). Such approach provides high level of integration and eliminates the need of galvanic contacts; however, it suffers from a major drawback which isthe propagation of parasitic modes in the circuit cavity if the MMIC is large enough to allow such modes to propagate. To mitigate this problem, this work suggests and investigates the use of electromagnetic bandgap (EBG) structures that suppresses those modes such as bed of nails and mushroom-type EBG structures. The proposed techniques are used to implement several on-chip packaging solutions that have an insertion loss as low as 0.6 dB at D-band (110-170 GHz). Moreover, the solutions are demonstrated in several active systems using various commercial MMIC technologies. The thesis also investigates the possibility of utilizing the commercially available packaging technologies such as Embedded Wafer Level Ball Grid Array (eWLB) packaging. Such technology has been widely used for integrated circuits operating below 100 GHz but was not attempted in the THz range before. This work attempts to push the limits of the technology and proposes novel solutions based on coupling structures implemented in the technology’s redistribution layers. The proposed solutions achieve reasonable performance at D-band that are suitable for low-cost mass production while allowing heterogeneous integration with other technologies as well. This work addresses integration challenges facing systems operating in the THz range and proposes high-performance interconnectivity solutions demonstrated in a wide range of commercial technologies and hence enables such systems to reach their full potential and meet the increasing market demands