Dr. Biman Bagchi a bibliometric portrait

Analyses bibliometrically 226 publications [Papers Published in journals-220, thesis [others 4] by Biman Bagchi, a renowned physical chemist from India, published during 1981 to 2002. The first contribution of the author was in 1981 at the age of 27. The number of his contributions in a year peaked in 1999 and 2002 when it touched 19. The author is highly productive in as much as on average the author has produced 10 papers per year. In the byline of authorship, Bagchi occupies the first authorship position in 69 cases. His collaborator A. Chandra occupies the first authorship position in 30 papers thus becoming Bagchi's closest collaborator. The journal has been the most preferred channel of communication of the author in as much as 220 papers out of 226 have been praced in journals. J. Chem. Phys. is found to be the most preferred journal that carried 91 papers of the author, followed by Chem. Phys. Lett. (21 papers). J. Phys. Chem. (19 papers), Proc. Indian Acad. Sci. - Chem. Sci. (13 papers), and others. Of the papers, 179 received 4030 citations and 47 received no citations. It is expected that more than 20 uncited papers till 2002 will receive citations in future. Three papers of the author have received more than 200 citations each, and another three received between 100-200 citations each. The number of papers receiving 10 citations or more total 92. On four different years the scientist has received more than 300 citations and his citation rate per paper has peaked at 18.98. The article shows with a concrete example the growth, peaking and declining of citation rate. A few new terms such as citation gain, citation loss, gaining citation rate and losing citation rate have been introduced and described

Acknowledgement Patterns in Research Articles: a Bibliometric Study based on Journal of Natural Rubber Research 1986-1997

Analyses the acknowledgements included in the research articles and short communications published in Journal of Natural Rubber Research (1986-1997) in respect of types, frequency of occurrence, individuals acknowledged, etc. Results indicate that 74% items contain acknowledgements; an average acknowledgement per item is 2.2; the most common type of acknowledgments relates to technical support. Peer interactive communication accounts for 44% of the total acknowledgements. The result of the study substantiates the earlier findings that a small number of individuals are highly acknowledged and the rest are acknowledged infrequently

INSDOC’S contribution to bibliometrics

Traces the history of bibliometric research, training and activities in INSDOC. Describes briefly the objectives, facilities, services, research activities, and publications of National Centre on Bibliometrics

Proper Matter Collineations of Plane Symmetric Spacetimes

We investigate matter collineations of plane symmetric spacetimes when the energy-momentum tensor is degenerate. There exists three interesting cases where the group of matter collineations is finite-dimensional. The matter collineations in these cases are either four, six or ten in which four are isometries and the rest are proper.Comment: 10 pages, LaTex, accepted for publication in Modern Physics Letters

Intersection representation of digraphs in trees with few leaves

The leafage of a digraph is the minimum number of leaves in a host tree in which it has a subtree intersection representation. We discuss bounds on the leafage in terms of other parameters (including Ferrers dimension), obtaining a string of sharp inequalities.Comment: 12 pages, 3 included figure

Simulating Quantum Dynamics with Entanglement Mean Field Theory

Exactly solvable many-body systems are few and far between, and the utility of approximate methods cannot be overestimated. Entanglement mean field theory is an approximate method to handle such systems. While mean field theories reduce the many-body system to an effective single-body one, entanglement mean field theory reduces it to a two-body system. And in contrast to mean field theories where the self-consistency equations are in terms of single-site physical parameters, those in entanglement mean field theory are in terms of both single- and two-site parameters. Hitherto, the theory has been applied to predict properties of the static states, like ground and thermal states, of many-body systems. Here we give a method to employ it to predict properties of time-evolved states. The predictions are then compared with known results of paradigmatic spin Hamiltonians.Comment: 8 pages, 3 figure

One-loop Evolution of a Rolling Tachyon

We study the time evolution of the one-loop diagram in Sen's rolling tachyon background. We find that at least in the long cylinder case they grow rapidly at late time, due to the exponential growth of the timelike oscillator terms in the boundary state. This can also be interpreted as the virtual open string pair creation in the decaying brane. This behavior indicates a breakdown of this rolling tachyon solution at some point during the evolution. We also discuss the closed string emission from this one-loop diagram, and the evolution of a one-loop diagram connecting a decaying brane to a stable brane, which is responsible for the physical open string creation on the stable brane.Comment: 21 pages, 2 figures; v2: references added, comments revised in various places; v3: footnotes 7&8 added, revised version to appear in PR

Patterns in Open String Field Theory Solutions

In open string field theory the kinetic operator mixes matter and ghost sectors, and thus the ghost structure of classical solutions is not universal. Nevertheless, we have found from numerical analysis that certain ratios of expectation values for states involving pure ghost excitations appear to be universal. We give an analytic expression for these ratios and find good evidence that they are common to all known solutions of open string field theory, including the tachyon vacuum solution, lump solutions and string fields representing marginal deformations. We also draw attention to a close correspondence between the expectation values for the pure matter components in the tachyon vacuum solution and those in the solution of a simpler equation for a ghost number zero string field. Finally we observe that the action of L_0 on the tachyon condensate gives a state that is approximately factorized into a matter and a ghost part.Comment: 21 pages, LaTe