Zitterbewegung of a heavy hole in presence of spin-orbit interactions

We study the $zitterbewegung$ of a heavy hole in presence of both cubic Rashba and cubic Dresselhaus spin-orbit interactions. On contrary to the electronic case, $zitterbewegung$ does not vanish for equal strength of Rashba and Dresselhaus spin-orbit interaction. This non-vanishing of $zitterbewegung$ is associated with the Berry phase. Due to the presence of the spin-orbit coupling the spin associated with the heavy hole precesses about an effective magnetic field. This spin precession produces a transverse spin-orbit force which also generates an electric voltage associated with $zitterbewegung$. We have estimated the magnitude of this voltage for a possible experimental detection of $zitterbewegung$.Comment: 6 pages, 3 figure

A Comparative Study on Selected Physical Fitness Components between Deaf & Dumb and Normal School Boys of West Bengal

Objective: The objective of the study was to compare the selected physical fitness components between the Deaf & Dumb and Normal school boys of west Bengal. Methodology: For the purpose of the study forty-two (N=42)) subjects were randomly chosen of which twenty-two were deaf and dumb boys (n1=22) and twenty were normal school boys (n2=20). The age of the children ranged from 12 to 20 years. They were selected from three separate districts of West Bengal - Kolkata, Burdwan and Hooghly. The five different physical fitness components i.e. Speed, Agility, Muscular endurance, Flexibility and Explosive leg strength were considered as variables for the present study. The data were collected by using standard tools and techniques. Statistics: Mean, standard deviation (SD) and independent t- test were the statistics used in this study for data interpretation. Level of significant difference between two groups was set at p<0.05. For statistical calculations Excel Spread Sheet of windows version 7 was used. Results: Result of present study revealed that in Speed, Agility and Muscular Endurance no significant difference exists between the Normal and Deaf & Dumb Boys. But in Flexibility & Explosive leg strength significant difference exist between the Normal and Deaf & Dumb Boys. Conclusion: It can be concluded from the results of the study that in flexibility the normal boys are better than the deaf and dumb boys but the Explosive leg strength of the Deaf & Dumb Boys are better than the normal boys

Aortic aneurysm and non-Hodgkin’s lymphoma in Marfan syndrome

The combination of Marfan syndrome with lymphoma is extremely rare. This report describes a case of Marfan syndrome who presented with chest discomfort and was diagnosed to have an aortic aneurysm and an additional incidental mediastinal mass that on further investigation turned out to be a diffuse large B cell lymphoma. We have suggested a hypothesis which can explain the occurrence of lymphoma in Marfan syndrome

On The Entanglement Entropy For Gauge Theories

We propose a definition for the entanglement entropy of a gauge theory on a spatial lattice. Our definition applies to any subset of links in the lattice, and is valid for both Abelian and Non-Abelian gauge theories. For $\mathbb{Z}_N$ and $U(1)$ theories, without matter, our definition agrees with a particular case of the definition given by Casini, Huerta and Rosabal. We also argue that in general, both for Abelian and Non-Abelian theories, our definition agrees with the entanglement entropy calculated using a definition of the replica trick. Our definition, however, does not agree with some standard ways to measure entanglement, like the number of Bell pairs which can be produced by entanglement distillation.Comment: 29 pages, 4 figures; section on Extended Lattice Construction revised and some changes in referencing; some of the discussion of the replica trick changed; section on SU(2) revised for clarit