Out-of-equilibrium density dynamics of a spinful Luttinger liquid

Using a Luttinger liquid theory we investigate the time evolution of the particle density of a one-dimensional spinful fermionic system with open boundaries and subject to a finite-duration quench of the inter-particle interaction. Taking into account also the turning on of an umklapp perturbation to the system Hamiltonian as a result of the quench, we study the possible formation of a Wigner molecule inside the system, focusing in particular on the sudden and adiabatic regimes. We show that the creation of this correlated state is essentially due to the propagation of "light-cone" perturbations through system which arise after both switching on and switching off the quenching protocol and that its behavior strongly depends on the quench duration.Comment: 10 pages, 2 figures. Proceedings submitted to Nuovo Cimento C - Colloquia and Communications in Physic

Modal dynamics for positive operator measures

The modal interpretation of quantum mechanics allows one to keep the standard classical definition of realism intact. That is, variables have a definite status for all time and a measurement only tells us which value it had. However, at present modal dynamics are only applicable to situations that are described in the orthodox theory by projective measures. In this paper we extend modal dynamics to include positive operator measures (POMs). That is, for example, rather than using a complete set of orthogonal projectors, we can use an overcomplete set of nonorthogonal projectors. We derive the conditions under which Bell's stochastic modal dynamics for projective measures reduce to deterministic dynamics, showing (incidentally) that Brown and Hiley's generalization of Bohmian mechanics [quant-ph/0005026, (2000)] cannot be thus derived. We then show how {\em deterministic} dynamics for positive operators can also be derived. As a simple case, we consider a Harmonic oscillator, and the overcomplete set of coherent state projectors (i.e. the Husimi POM). We show that the modal dynamics for this POM in the classical limit correspond to the classical dynamics, even for the nonclassical number state $\ket{n}$. This is in contrast to the Bohmian dynamics, which for energy eigenstates, the dynamics are always non-classical.Comment: 14 page

The Long Shadow of Income on Trustworthiness

We employ a behavioural measure of trustworthiness obtained from an experiment carried out with a sample of the general British population whose individuals were extensively interviewed on earlier occasions. These previous interviews allow us to have very good income measures, and in particular to construct a measure of relative income that uses past income as a reference point. Our basic finding is that given past income, higher current income increases trustworthiness and, given current income, higher past income reduces trustworthiness. Past income determines the level of financial aspirations and whether or not these are fulfilled by the level of current income affects trustworthiness. But past income has a disproportionately large effect on trustworthiness compared to that predicted by the relative income theory, and this leads us to suspect that past income may also capture heterogeneity in relevant subjects’ dispositions, with more opportunistic subjects being less trustworthy and having higher average incomes. We suggest and estimate a two-tier model in which relative income has the same positive effect within each past income class, but people in higher past income classes have a lower fundamental levels of trustworthiness.trustworthiness, relative income

Dynamical parameter estimation using realistic photodetection

We investigate the effect of imperfections in realistic detectors upon the problem of quantum state and parameter estimation by continuous monitoring of an open quantum system. Specifically, we have reexamined the system of a two-level atom with an unknown Rabi frequency introduced by Gambetta and Wiseman [Phys. Rev. A 64, 042105 (2001)]. We consider only direct photodetection and use the realistic quantum trajectory theory reported by Warszawski, Wiseman, and Mabuchi [Phys. Rev. A 65, 023802 (2002)]. The most significant effect comes from a finite bandwidth, corresponding to an uncertainty in the response time of the photodiode. Unless the bandwidth is significantly greater than the Rabi frequency, the observer's ability to obtain information about the unknown Rabi frequency, and about the state of the atom, is severely compromised. This result has implications for quantum control in the presence of unknown parameters for realistic detectors, and even for ideal detectors, as it implies that most of the information in the measurement record is contained in the precise timing of the detections.Comment: 8 pages, 6 figure

Voice Feminization: Voice Therapy vs. Surgical Intervention: A Systematic Review

Abstract Purpose: Transgender individuals often seek to alter their vocal characteristics. For Male to Female (MtF) transgender individuals, attaining a feminine voice may be particularly challenging. The objective of this systematic review is to determine whether MtF transgender individuals who receive voice feminization therapy alone or Wendler’s Glottoplasty (WG) surgical intervention with subsequent voice therapy yield greater outcomes in frequency and self-perception. Method: A systematic review of the literature was conducted by using PubMed and Ovid to search terms pertaining to voice feminization. The articles were reviewed and appraised by the authors for inclusionary criteria, exclusionary criteria, and quality. Inclusionary criteria included: 1) adult MtF Transgender individuals, 2) pre and post measures of fundamental frequency (fo), 3) post puberty age, 4) measure of perception of femininity, and 5) patients who underwent WG (articles pertaining to surgical intervention only). Results: A total of 82 articles were identified and 12 met inclusionary criteria for this systematic review. Overall, the quality of the studies was moderate. Outcome measures included frequency range and frequency gain. The authors were unable to compare measurements of self-perception and perception of femininity due to the variability in assessments. Conclusions: Patients who opted for surgical intervention experienced a greater increase in fo but a decrease in frequency range. Conversely, patients who participated in voice feminization therapy alone were found to exhibit smaller gains in fo and an increase in frequency range. This implies that both voice feminization therapy and surgical intervention are effective methods for increasing the frequency of voice. Limitations of this research include the subjective nature of self-perception measures, variability in measurements of perception of femininity, and overall limited research regarding this population.https://scholarworks.uvm.edu/csdms/1009/thumbnail.jp