Non-Destructive Discrimination of arbitrary set of orthogonal quantum states by NMR using Quantum Phase Estimation

An algorithm based on quantum phase estimation, which discriminates quantum states nondestructively within a set of arbitrary orthogonal states, is described and experimentally verified by a NMR quantum information processor. The procedure is scalable and can be applied to any set of orthogonal states. Scalability is demonstrated through Matlab simulation

Singlet state creation and Universal quantum computation in NMR using Genetic Algorithm

Experimental implementation of a quantum algorithm requires unitary operator decomposition. Here we treat the unitary operator decomposition as an optimization problem and use Genetic Algorithm, a global optimization method inspired by nature's evolutionary process for operator decomposition. As an application, we apply this to NMR Quantum Information Processing and find a probabilistic way of doing universal quantum computation using global hard pulses. We also demonstrate efficient creation of singlet state (as a special case of Bell state) directly from thermal equilibrium using an optimum sequence of pulses

Employer matching and 401 (k) participation: evidence from the health and retirement study

Employer matching of employee 401(k) contributions can provide a powerful incentive to save for retirement and is a key component in pension-plan design in the United States. Using detailed administrative contribution, earnings, and pension-plan data from the Health and Retirement Study, this analysis formulates a life-cycle-consistent discrete choice regression model of 401(k) participation and estimates the determinants of participation accounting for non-linearities in the household budget set induced by matching. The estimates indicate that an increase in the match rate by 25 cents per dollar of employee contribution raises 401(k) participation by 3.75 to 6 percentage points, and the estimated elasticity of participation with respect to matching ranges from 0.02-0.07. The estimated elasticity of intertemporal substitution is 0.74-0.83. Overall, the analysis reveals that matching is a rather poor instrument with which to raise retirement saving.Saving and investment ; Taxation ; Pensions

Financial literacy and mortgage equity withdrawals

The recent U.S. consumption boom and the subsequent surge in mortgage defaults have been linked to mortgage equity withdrawals (MEWs). MEWs are correlated with covariates consistent with a permanent income framework augmented for credit-constraints. Nevertheless, many households are financially illiterate. We assess the unexplored linkages between “active MEW” and measures of financial literacy using panel data from the Health and Retirement Study (HRS). Findings indicate that declines in mortgage interest rates encouraged MEWs. Nevertheless, financially illiterate households were significantly more likely to withdraw housing equity via traditional first or second mortgages (including cash-out mortgage refinancings but not home equity loans).> ; We find that the financially less savvy are 3–5 percentage points more likely to engage in this type of MEW relative to those who answered financial literacy questions correctly. Also significant were state differences in debtor versus creditor interests in bankruptcy, with loan demand effects outweighing loan supply effects across states.Consumption (Economics) - United States ; Credit control

Employer Matching and 401(k) Saving: Evidence from the Health and Retirement Study

Employer matching of employee 401(k) contributions can provide a powerful incentive to save for retirement and is a key component in pension-plan design in the United States. Using detailed administrative contribution, earnings, and pension-plan data from the Health and Retirement Study, this analysis formulates a life-cycle-consistent econometric specification of 401(k) saving and estimates the determinants of saving accounting for non-linearities in the household budget set induced by matching. The participation estimates indicate that an increase in the match rate by 25 cents per dollar of employee contribution raises 401(k) participation by 3.75 to 6 percentage points, and the estimated elasticity of participation with respect to matching ranges from 0.02-0.07. The parametric and semi-parametric estimates for saving indicate that an increase in the match rate by 25 cents per dollar of employee contribution raises 401(k) saving by $400-$700 (in 1991 dollars). The estimated elasticity of 401(k) saving to matching is also small and ranges from 0.09-0.12 overall, with just under half of this effect on the intensive margin. Overall, the analysis reveals that matching is a rather poor policy instrument with which to raise retirement saving.

The elasticity of intertemporal substitution: new evidence from 401(k) participation

A key parameter in economics is the elasticity of intertemporal substitution (EIS), which measures the extent to which consumers shift total expenditures across time in response to changes in the effective rate of return. In contrast to the previous literature, which primarily has relied on Euler equation methods and generated a wide range of estimates, we show how a life-cycle-consistent econometric specification of employee 401(k) participation along with plausibly exogenous variation in rates of return due to employer matching contributions can be used to generate new estimates of the EIS. Because firms often cap the generosity of the match, employer matching generates nonlinearities in household budget sets. We draw on non-linear budget-set estimation methods rooted in the public economics literature, and using detailed administrative contribution, earnings, and pension-plan data for a sample of 401(k)-eligible households from the Health and Retirement Study, we estimate the EIS to be 0.74 in our richest specification, with a 95% confidence interval that ranges from 0.37 to 1.21.Elasticity (Economic) ; Consumer behavior ; Econometric models

A Stochastic model for dynamics of FtsZ filaments and the formation of Z-ring

Understanding the mechanisms responsible for the formation and growth of FtsZ polymers and their subsequent formation of the $Z$-ring is important for gaining insight into the cell division in prokaryotic cells. In this work, we present a minimal stochastic model that qualitatively reproduces {\it in vitro} observations of polymerization, formation of dynamic contractile ring that is stable for a long time and depolymerization shown by FtsZ polymer filaments. In this stochastic model, we explore different mechanisms for ring breaking and hydrolysis. In addition to hydrolysis, which is known to regulate the dynamics of other tubulin polymers like microtubules, we find that the presence of the ring allows for an additional mechanism for regulating the dynamics of FtsZ polymers. Ring breaking dynamics in the presence of hydrolysis naturally induce rescue and catastrophe events in this model irrespective of the mechanism of hydrolysis.Comment: Replaced with published versio

Minimum impact and immediacy of citations to physics open archives of arXiv.org: Science Citation Index based reports

The present work has calculated the minimum Open Archive Impact Factors and Open Archive Immediacy Index for the Physics Classes of arXiv.org as calculated for traditional journals in Journal Citation Reports of the Institute of Scientific Information using Science Citation Index without the citation by the classes itself. The calculated Impact Factors reveal that High-Energy Physics classes of arXiv.org (‘hep-th’, ‘hep-lat’, ‘hep-ex’, and ‘hep-ph’) have made more impact on the scientific community than any other classes except ‘nucl-ex’. The Impact Factors for the year 2003 are: ‘hep-th’ (0.999), ‘nucl-ex’ (0.806), ‘hep-lat’ (0.766), ‘hep-ex’ (0.73), ‘hep-ph’ (0.719), ‘nucl-th’ (0.338), ‘quant-ph’ (0.334), ‘cond-mat’ (0.313), ‘astro-ph’ (0.195), ‘math-ph’ (0.162), ‘physics’ (0.061), and ‘gr-qc’ (0.002). If the period for getting the citations to the open archive classes is considered one year as against two years for journal articles, the rank of the classes is the same. The immediacy of citing the Open Archives is also high for the High-Energy Physics classes. The Immediacy Indexes for the year 2003 are: ‘hep-ex’ (0.619), ‘hep-th’ (0.454), ‘hep-ph’ (0.44), ‘hep-lat’ (0.263), ‘nucl-ex’ (0.238), ‘quant-ph’ (0.202), ‘nucl-th’ (0.185), ‘cond-mat’ (0.168), ‘astro-ph’ (0.094), ‘math-ph’ (0.075), ‘physics’ (0.03), and ‘gr-qc’ (0.002). The impact is definitely much higher than what is concluded from the calculated factors because self-citations are not reckoned in the study. Use of web-tools like ‘Citebase’, ‘Citeseer’ etc. may strengthen the above argument