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Islamabad, Pakistan

The Quaid-i-Azam University , is a public research university located in Islamabad, Pakistan. Consisting of four faculties, nine affiliated research institutes, the university is consistently ranked as the top university in Pakistan " by the HEC and is ranked by Quacquarelli Symonds ranking among the top 500 universities in the world in 2013, while it was ranked at 69th top university of the world in field of 'Engineering and Technology'.With overall ~7,800 students currently attending the university, it offers undergraduate, post-graduate, and doctoral programmes in various academic disciplines. The Quaid-i-Azam University scholars have played critical role in the development of various academic disciplines including in social and natural science. Its school of social science is well known for its leading contribution to the movement in critical analysis. Also, the university's school of natural science holds an international prestige for its leading and developmental role in physics and mathematics since its establishment.Covering the approximated area of 1700 acres below the Margalla Hills, the university is internationally known for its higher learning, technological advancement, and intellectual interaction with a joint collaboration in various academic discipline with various international institutes, including the United Nations. It is one of the most popular universities in the country and has attracted world renowned scholars and intellectuals to serve as faculty, researchers, or alumni since its establishment in 1967. Wikipedia.

Quantum discord quantifies the total non-classical correlations in mixed states. It is the difference between total correlation, measured by quantum mutual information, and the classical correlation. Another step forward towards the quantification of quantum discord was by Dakić et al. (Phys Rev Lett 105:190502, 2010) who introduced the geometric measure of quantum discord (GMQD) and derived an explicit formula for a two-qubit state. Recently, Luo and Fu (Phys Rev Lett 106:120401, 2011) introduced measurement-induced nonlocality (MIN) as a measure of nonlocality for a bipartite quantum system. The dynamics of GMQD is recently considered by Song et al. (arXiv: quant/ph.1203.3356) and Zhang et al. (Eur Phys J D 66:34, 2012) for inertial observers. However, the topic requires due attention in noninertial frames, particularly, from the perspective of MIN. Here I consider X -structured bipartite quantum system in noninertial frames and analyze the decoherence dynamics of GMQD and MIN at finite temperature. The dynamics under the influence of amplitude damping, depolarizing and phase flip channels is discussed. It is worth-noting that initial state entanglement plays an important role in bipartite states. It is possible to distinguish the Bell, Werner and general type initial quantum states using GMQD. Sudden transition in the behaviour of GMQD and MIN occurs depending upon the mean photon number of the local environment. The transition behaviour disappears for larger values of n̄ i.e. n̄ > 0.3 It becomes more prominent, when environmental noise is introduced in the system. In the presence of environmental noise, as we increase the value of acceleration r, GMQD and MIN decay due to Unruh effect. The effect is prominent for the phase flip and amplitude damping channels. However, in case of depolarizing channel, no sudden change in the behaviour of GMQD and MIN is observed. The environmental noise has stronger affect on the dynamics of GMQD and MIN as compared to the Unruh effect. Furthermore, Werner like states are more robust than General type initial states at finite temperature. © 2013 Springer Science+Business Media New York.

Ramzan M.,Quaid-i-Azam University
Quantum Information Processing | Year: 2013

Effect of decoherence and correlated noise on the entanglement of X-type state of the Dirac fields in the non-inertial frame is investigated. A two qubit X-state is considered to be shared between the partners where Alice is in inertial frame and Rob in an accelerated frame. The concurrence is used to quantify the entanglement of the X-state system influenced by time correlated amplitude damping, depolarizing and bit flip channels. It is seen that amplitude damping and bit flip channels heavily influence the entanglement of the system as compared to the depolarizing channel. It is found possible to avoid entanglement sudden death (ESD) for all the channels under consideration for μ > 0.75 for any type of initial state. No ESD behaviour is seen for depolarizing channel in the presence of correlated noise for entire range of decoherence parameter p and Rob's acceleration r. It is also seen that the effect of environment is much stronger than that of acceleration of the accelerated partner. Furthermore, it is investigated that correlated noise compensates the loss of entanglement caused by the Unruh effect. © 2012 Springer Science+Business Media, LLC.

Nawaz A.,Quaid-i-Azam University
Journal of Physics A: Mathematical and Theoretical | Year: 2012

We quantize prisoners' dilemma in the presence of collective dephasing with a dephasing rate γ. It is shown that for a two-parameter set of strategies, Q⊗Q is Nash equilibrium below a cut-off value of time. Beyond this cut-off it bifurcates into two new Nash equilibria Q⊗D and D⊗Q. Furthermore, for the maximum value of decoherence C⊗D and D⊗C also become Nash equilibria. At this stage the game has four Nash equilibria. On the other hand, for a three-parameter set of strategies, there is no pure strategy Nash equilibrium; however, there is a mixed strategy (non-unique) Nash equilibrium that is not affected by collective dephasing. © 2012 IOP Publishing Ltd.

Irfan Ali M.,Quaid-i-Azam University
Applied Soft Computing Journal | Year: 2011

Concept of an approximation space associated with each parameter in a soft set is discussed and an approximation space associated with the soft set is defined. For any subset X of the universe U, there is a fuzzy subset of U associated with each parameter of the soft set, also there is a fuzzy subset associated with the soft set. Furthermore each soft set over a set U, gives rise to a fuzzy soft set over P(U) and induces a soft equivalence relation over P(U). © 2011 Elsevier B.V.

Malik S.,Quaid-i-Azam University
European Journal of Human Genetics | Year: 2012

Syndactyly is one of the most common hereditary limb malformations depicting the fusion of certain fingers and/or toes. It may occur as an isolated entity or a component of more than 300 syndromic anomalies. Syndactylies exhibit great inter-and intra-familial clinical variability. Even within a subject, phenotype can be unilateral or bilateral and symmetrical or asymmetrical. At least nine non-syndromic syndactylies with additional sub-types have been characterized. Most of the syndactyly types are inherited as autosomal dominant but two autosomal recessive and an X-linked recessive entity have also been described. Whereas the underlying genes/mutations for types II-1, III, IV, V, and VII have been worked out, the etiology and molecular basis of the other syndactyly types remain unknown. In this communication, based on an overview of well-characterized isolated syndactylies, their cardinal phenotypes, inheritance patterns, and clinical and genetic heterogeneities, a current classification scheme is presented. Despite considerable progress in the understanding of syndactyly at clinical and molecular levels, fundamental questions regarding the disturbed developmental mechanisms leading to fused digits, remain to be answered. © 2012 Macmillan Publishers Limited All rights reserved.

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