Dual vortices in Abelian projected SU(2) in the Polyakov gauge

We study dual Abrikosov vortices in Abelian projected SU(2) gauge theory in the Polyakov gauge. We show that vortices are present in this gauge but they are suppressed with respect to the maximal Abelian gauge. We interpret this difference in terms of the shielding of the electric charge by the charged coset fields.Comment: Talk presented at LATTICE96(topology), 3 pages, latex, 4 eps figures, uses epsfig and espcrc2.sty (included

Six years of E-JournALL. Reflections on open access, international, multilingual applied linguistics publishing

E-JournALL, EuroAmerican Journal of Applied Linguistics and Languages published its first issue in November 2014. The journal was meant to be a bridge: between scholars working in Europe and the Americas; between scholars writing in English, Italian, and Spanish; and between scholars publishing in the journal and researchers and language teachers across the world with or without university-paid access to expensive journal subscriptions. The journal was founded, therefore, on three pillars: internationalism, multilingualism, and open access. In this reflection, written at the end of our sixth year as a journal—and with the release of our 12th issue and 97th article—we look back on the last six years, taking stock of how well we have lived up to our founding principles, and we look ahead to the journal’s next six years

Dynamical evolution of escaped plutinos, another source of Centaurs

It was shown in previous works the existence of weakly chaotic orbits in the plutino population that diffuse very slowly. These orbits correspond to long-term plutino escapers and then represent the plutinos that are escaping from the resonance at present. In this paper we perform numerical simulations in order to explore the dynamical evolution of plutinos recently escaped from the resonance. The numerical simulations were divided in two parts. In the first one we evolved 20,000 test particles in the resonance in order to detect and select the long-term escapers. In the second one, we numerically integrate the selected escaped plutinos in order to study their dynamical post escaped behavior. Our main results include the characterization of the routes of escape of plutinos and their evolution in the Centaur zone. We obtained a present rate of escape of plutinos between 1 and 10 every 10 years. The escaped plutinos have a mean lifetime in the Centaur zone of 108 Myr and their contribution to the Centaur population would be a fraction of less than 6 % of the total Centaur population. In this way, escaped plutinos would be a secondary source of Centaurs.Comment: Accepted for publication in A&

Dynamically generated electric charge distributions in Abelian projected SU(2) lattice gauge theories

We show in the maximal Abelian gauge the dynamical electric charge density generated by the coset fields, gauge fixing and ghosts shows antiscreening as in the case of the non-Abelian charge. We verify that with the completion of the ghost term all contributions to flux are accounted for in an exact lattice Ehrenfest relation.Comment: LATTICE98(confine

Operator product expansion and factorization in the H3+H_3^+-WZNW model

Precise descriptions are given for the operator product expansion of generic primary fields as well as the factorization of four point functions as sum over intermediate states. The conjecture underlying the recent derivation of the space-time current algebra for string theory on $ADS_3$ by Kutasov and Seiberg is thereby verified. The roles of microscopic and macroscopic states are further clarified. The present work provides the conformal field theory prerequisites for a future study of factorization of amplitudes for string theory on $ADS_3$ as well as operator product expansion in the corresponding conformal field theory on the boundary.Comment: 28 pages, references adde

Quantum Computation Based on Retarded and Advanced Propagation

Computation is currently seen as a forward propagator that evolves (retards) a completely defined initial vector into a corresponding final vector. Initial and final vectors map the (logical) input and output of a reversible Boolean network respectively, whereas forward propagation maps a one-way propagation of logical implication, from input to output. Conversely, hard NP-complete problems are characterized by a two-way propagation of logical implication from input to output and vice versa, given that both are partly defined from the beginning. Logical implication can be propagated forward and backward in a computation by constructing the gate array corresponding to the entire reversible Boolean network and constraining output bits as well as input bits. The possibility of modeling the physical process undergone by such a network by using a retarded and advanced in time propagation scheme is investigated. PACS numbers: 89.70.+c, 02.50.-r, 03.65.-w, 89.80.+hComment: Reference of particle statistics to computation speed up better formalized after referee's suggestions. Modified: second half of Section I, Section IIC after eq.(7), Section IID and E. Figure unchange

Automatic Detection and Compression for Passive Acoustic Monitoring of the African Forest Elephant

In this work, we consider applying machine learning to the analysis and compression of audio signals in the context of monitoring elephants in sub-Saharan Africa. Earth's biodiversity is increasingly under threat by sources of anthropogenic change (e.g. resource extraction, land use change, and climate change) and surveying animal populations is critical for developing conservation strategies. However, manually monitoring tropical forests or deep oceans is intractable. For species that communicate acoustically, researchers have argued for placing audio recorders in the habitats as a cost-effective and non-invasive method, a strategy known as passive acoustic monitoring (PAM). In collaboration with conservation efforts, we construct a large labeled dataset of passive acoustic recordings of the African Forest Elephant via crowdsourcing, compromising thousands of hours of recordings in the wild. Using state-of-the-art techniques in artificial intelligence we improve upon previously proposed methods for passive acoustic monitoring for classification and segmentation. In real-time detection of elephant calls, network bandwidth quickly becomes a bottleneck and efficient ways to compress the data are needed. Most audio compression schemes are aimed at human listeners and are unsuitable for low-frequency elephant calls. To remedy this, we provide a novel end-to-end differentiable method for compression of audio signals that can be adapted to acoustic monitoring of any species and dramatically improves over naive coding strategies

Cross-Correlation of spectroscopic and photometric galaxy surveys: cosmology from lensing and redshift distortions

Cosmological galaxy surveys aim at mapping the largest volumes to test models with techniques such as cluster abundance, cosmic shear correlations or baryon acoustic oscillations (BAO), which are designed to be independent of galaxy bias. Here we explore an alternative route to constrain cosmology: sampling more moderate volumes with the cross-correlation of photometric and spectroscopic surveys. We consider the angular galaxy-galaxy autocorrelation in narrow redshift bins and its combination with different probes of weak gravitational lensing (WL) and redshift space distortions (RSD). Including the cross-correlation of these surveys improves by factors of a few the constraints on both the dark energy equation of state w(z) and the cosmic growth history, parametrized by \gamma. The additional information comes from using many narrow redshift bins and from galaxy bias, which is measured both with WL probes and RSD, breaking degeneracies that are present when using each method separately. We show forecasts for a joint w(z) and \gamma figure of merit using linear scales over a deep (i<24) photometric survey and a brighter (i<22.5) spectroscopic or very accurate (0.3%) photometric redshift survey. Magnification or shear in the photometric sample produce FoM that are of the same order of magnitude of those of RSD or BAO over the spectroscopic sample. However, the cross-correlation of these probes over the same area yields a FoM that is up to a factor 100 times larger. Magnification alone, without shape measurements, can also be used for these cross-correlations and can produce better results than using shear alone. For a spectroscopic follow-up survey strategy, measuring the spectra of the foreground lenses to perform this cross-correlation provides 5 times better FoM than targeting the higher redshift tail of the galaxy distribution to study BAO over a 2.5 times larger volume.Comment: Small cosmetic changes to match MNRAS published versio

Far-field spectral characterization of conical emission and filamentation in Kerr media

By use of an imaging spectrometer we map the far-field ($\theta-\lambda$) spectra of 200 fs optical pulses that have undergone beam collapse and filamentation in a Kerr medium. By studying the evolution of the spectra with increasing input power and using a model based on stationary linear asymptotic wave modes, we are able to trace a consistent model of optical beam collapse high-lighting the interplay between conical emission, multiple pulse splitting and other effects such as spatial chirp.Comment: 8 pages, 9 figure