LOFF and breached pairing with cold atoms

We investigate here the Cooper pairing of fermionic atoms with mismatched fermi surfaces using a variational construct for the ground state. We determine the state for different values of the mismatch of chemical potential for weak as well as strong coupling regimes including the BCS BEC cross over region. We consider Cooper pairing with both zero and finite net momentum. Within the variational approximation for the ground state and comparing the thermodynamic potentials, we show that (i) the LOFF phase is stable in the weak coupling regime, (ii) the LOFF window is maximum on the BEC side near the Feshbach resonance and (iii) the existence of stable gapless states with a single fermi surface for negative average chemical potential on the BEC side of the Feshbach resonance.Comment: 14 pages including 10 figures, Some figures redrawn with more data points, more references added, few sentences added in discussions, version to appear in Eur. Phys. Journal

Skin Uncertainty in Multi-Layered Commingled Reservoirs with Non-Uniform Formation Damage

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A Variational Approach to Bound States in Quantum Field Theory

We consider here in a toy model an approach to bound state problem in a nonperturbative manner using equal time algebra for the interacting field operators. Potential is replaced by offshell bosonic quanta inside the bound state of nonrelativistic particles. The bosonic dressing is determined through energy minimisation, and mass renormalisation is carried out in a nonperturbative manner. Since the interaction is through a scalar field, it does not include spin effects. The model however nicely incorporates an intuitive picture of hadronic bound states in which the gluon fields dress the quarks providing the binding between them and also simulate the gluonic content of hadrons in deep inelastic collisions.Comment: latex, revtex, 22 page

Vacuum structure and effective potential at finite temperature: a variational approach

We compute the effective potential for $\phi^4$ theory with a squeezed coherent state type of construct for the ground state. The method essentially consists in optimising the basis at zero and finite temperatures. The gap equation becomes identical to resumming the infinite series of daisy and super daisy graphs while the effective potential includes multiloop effects and agrees with that obtained through composite operator formalism at finite temperature.Comment: 15 pages, Revtex, No figures, to appear in Jou. of Phys.G(Nucl. and Part. Phys.

A VAR Model of Monetary Policy and Hypothetical Case of Inflation Targeting in India

The empirical VAR literature on identification and measurement of the impact of monetary policy shocks on the real side of the economy is fairly comprehensive for developed economies but very limited for emerging and transition economies. In this study, we propose an identification scheme, for a developing economy taking India as a case study, which is able to capture the monetary transmission mechanism without giving rise to any empirical anomalies. We use a VAR approach with recursive contemporaneous restrictions and identify monetary policy shocks by modelling the reaction function of the central bank and structure of the economy. The effect of monetary policy shocks on the exchange rate and other macroeconomic variables is consistent with the predictions of a broad set of theoretical models. This set-up is used to build a hypothetical case of inflation targeting where the monetary policy instrument is set after looking at the current values of inflation only. This is in contrast with the „multiple indicator approach‟ currently followed by Reserve Bank of India. This hypothetical scenario of inflation targeting suggests a sharper response of the interest rate (monetary policy instrument) to shocks and strengthening of the exchange rate channel in transmission of interest rate impulses. This study also provides some useful implications on the type of theoretical framework which can be used to model the evolution of monetary policy for a developing economy like India.India, Inflation Targeting, Monetary policy, VAR