Fine-grained entanglement loss along renormalization group flows

We explore entanglement loss along renormalization group trajectories as a basic quantum information property underlying their irreversibility. This analysis is carried out for the quantum Ising chain as a transverse magnetic field is changed. We consider the ground-state entanglement between a large block of spins and the rest of the chain. Entanglement loss is seen to follow from a rigid reordering, satisfying the majorization relation, of the eigenvalues of the reduced density matrix for the spin block. More generally, our results indicate that it may be possible to prove the irreversibility along RG trajectories from the properties of the vacuum only, without need to study the whole hamiltonian.Comment: 5 pages, 3 figures; minor change

Support of Gulf of Mexico Hydrate Research Consortium: Activities to Support Establishment of a Sea Floor Monitoring Station Project

The Gulf of Mexico Hydrates Research Consortium (GOM-HRC) was established in 1999 to assemble leaders in gas hydrates research. The Consortium is administered by the Center for Marine Resources and Environmental Technology, CMRET, at the University of Mississippi. The primary objective of the group is to design and emplace a remote monitoring station or sea floor observatory (MS/SFO) on the sea floor in the northern Gulf of Mexico by the year 2007, in an area where gas hydrates are known to be present at, or just below, the sea floor. This mission, although unavoidably delayed by hurricanes and other disturbances, necessitates assembling a station that will monitor physical and chemical parameters of the marine environment, including sea water and sea-floor sediments, on a more-or-less continuous basis over an extended period of time. In 2005, biological monitoring, as a means of assessing environmental health, was added to the mission of the MS/SFO. Establishment of the Consortium has succeeded in fulfilling the critical need to coordinate activities, avoid redundancies and communicate effectively among researchers in the arena of gas hydrates research. Complementary expertise, both scientific and technical, has been assembled to promote innovative research methods and construct necessary instrumentation. The observatory has now achieved a microbial dimension in addition to the geophysical, geological, and geochemical components it had already included. Initial components of the observatory, a probe that collects pore-fluid samples and another that records sea floor temperatures, were deployed in Mississippi Canyon 118 in May of 2005. Follow-up deployments, planned for fall 2005, had to be postponed due to the catastrophic effects of Hurricane Katrina (and later, Rita) on the Gulf Coast. Station/observatory completion, anticipated for 2007, will likely be delayed by at least one year. The CMRET has conducted several research cruises during this reporting period: one in April, one in June, one in September. April's effort was dedicated to surveying the mound at MC118 with the Surface-Source-Deep-Receiver (SSDR) seismic surveying system. This survey was completed in June and water column and bottom samples were collected via box coring. A microbial filtering system developed by Consortium participants at the University of Georgia was also deployed, run for {approx}12 hours and retrieved. The September cruise, designed to deploy, test, and in some cases recover, geochemical and microbial instruments and experiments took place aboard Harbor Branch's Seward Johnson and employed the Johnson SeaLink manned submersible. The seafloor monitoring station/observatory is funded approximately equally by three federal Agencies: Minerals Management Services (MMS) of the Department of the Interior (DOI), National Energy Technology Laboratory (NETL) of the Department of Energy (DOE), and the National Institute for Undersea Science and Technology (NIUST), an agency of the National Oceanographic and Atmospheric Administration (NOAA). Subcontractors with FY03 funding fulfilled their technical reporting requirements in a previously submitted report (41628R10). Only unresolved matching funds issues remain and will be addressed in the report of the University of Mississippi's Office of Research and Sponsored Programs. In addition, Barrodale Computing Services Ltd. (BCS) completed their work; their final report is the bulk of the semiannual report that precedes (abstract truncated

Cross-Linguistic Investigations of Syntactic Creativity Errors In Children's Wh-Questions

This dissertation investigates the relationship between competence and processing in children’s first language acquisition, particularly of biclausal wh-questions. English-speaking children make consistent errors in production and comprehension of these questions. In production, these errors surface in the form of medial wh-phrases as in (1) when the child wishes to express (2) (Thornton, 1990). In comprehension, children respond to questions such as (3) as if the medial wh-phrase what were the question to answer (de Villiers and Roeper, 1995). (1) What do you think who the cat chased? (2) Who do you think the cat chased? (3) Q: How did the boy say what he caught? Response: A fish! These errors are particularly interesting because they resemble “Wh-Scope Marking” (WSM), which is attested in languages such as German (as seen in (4)), but not in English. (4) Was hat Stefan Selina erzählt, was er stehlen wird? What did Steven tell Sherry (what) he would steal? Together, errors such as those in (1) and (3) suggest children may adopt multiple UG licensed grammars (Yang, 2002; Legendre, Vainikka, Hagstrom, & Todorova, 2002). This would be an example of syntactic creativity: the use of a UG-licensed grammar which is not the target grammar (Schulz, 2011). This dissertation investigates whether these errors are true examples of syntactic creativity. We begin with a thorough investigation of the cross-linguistic variation in WSM and examine the particular pragmatic contexts which license it. We then describe a series of experiments which examine children’s ability to produce and comprehend biclausal wh-questions. Not only do we find no correlation between the two error types (which we would predict under a parameter-based view of the grammar), we find that these errors are correlated with children’s working memory. Finally, we find that German-speaking children’s performance on these tasks shows a striking resemblance to the English-speaking children. Our findings suggest that these errors are not the result of variation in the target grammar or grammar competence, but rather the result of something these children share: their immature processing mechanisms

Orbifold Duality Symmetries and Quantum Hall systems

We consider the possible role that chiral orbifold conformal field theories may play in describing the edge state theories of quantum Hall systems. This is a generalization of work that already exists in the literature, where it has been shown that 1+1 chiral bosons living on a n-dimensional torus, and which couple to a U_1 gauge field, give rise to anomalous electric currents, the anomaly being related to the Hall conductivity. The well known $O(n,n;Z)$ duality group associated with such toroidal conformal field theories transforms the edge states and Hall conductivities in a way which makes interesting connections between different theories, e.g. between systems exhibiting the integer and fractional quantum Hall effect. In this paper we try to explore the extension of these constructions to the case where such bosons live on a n-dimensional orbifold. We give a general formalism for discussing the relevant quantities like the Hall conductance and their transformation under the duality groups present in orbifold compactifications. We illustrate these ideas by presenting a detailed analysis of a toy model based on the two-dimensional Z_3 orbifold. In this model we obtain new classes of filling fractions, which generally the correspond to fermionic edge states carrying fractional electric charge. We also consider the relation between orbifold edge theories and Luttinger liquids (LL's), which in the past have provided important insights into the physics of quantum Hall systems.Comment: 35 pages, latex file. Factors corrected in some equations, typos corrected, references added. Also some clarifications of various points. Version to appear in Nuclear Physics

En undersøkelse av: forholdet mellom maskulin organisasjonskultur og kjønnsbalanse på ledernivå i revisjonsbransjen

Formålet med oppgaven har vært å finne ut om det er et forhold mellom maskulin organisasjonskultur og kjønnsbalanse på ledernivå i revisjonsbransjen. Vi har benyttet oss av velkjent teori innenfor feltet. Schein sin modell ble brukt som en ramme i håp om at den ville gjøre oppgaven mer oversiktlig og dermed hjelpe oss å konkludere. I tillegg benyttet vi oss av Hofstede sin definisjon av maskuline og feminine trekk innenfor organisasjonskultur, som et verktøy for å navigere seg i Schein sin modell. Tidligere forskning om kjønnsbalanse ville være sentral for å vite hvilken retning prosjektet skulle gå i, og for å kunne drøfte problemstillingen. I dette prosjektet har vi tatt i bruk semistrukturerte dybdeintervjuer. Vi innhentet informasjon fra to respondenter fra ulike organisasjoner. Videre analyserte vi empirien opp mot teori for å kunne finne forhold mellom de to komponentene. Vi har i denne bacheloroppgaven funnet at det er mer feminin organisasjonskultur enn det vi i utgangspunktet hadde antatt. Tema har en ekstremt høy grad av kompleksitet, og krever en dyp kompetanse på tvers av flere fagfelt som forbigår en bacheloroppgave. På bakgrunnen av dette fant vi at oppgaven vår ikke var tilstrekkelig for å trekke noen faste konklusjoner. Vi har likevel avdekket noen overraskende funn og mener derfor at dette prosjektet er egnet som et forarbeid for videre forskning

Production of compact plants by overexpression of AtSHI in the ornamental Kalanchoe

Growth retardation is an important breeding aim and an essential part of horticultural plant production Here, the potential of transferring the Arabidopsis short internode (shi) mutant phenotype was explored by expressing the AtSHI gene in the popular ornamental plant Kalanchoe A 35S-AtSHI construct was produced and transferred into eight genetically different cultivars of Kalanchoe by Agrobacterium tumefaciens The resulting transgenic plants showed dwarfing phenotypes like reduced plant height and diameter, and also more compact inflorescences, as a result of increased vegetative height The shi phenotype was stable over more than five vegetative subcultivations Compared with Arabidopsls, the ectopic expression of AtSHI in Kalanchoe showed several differences None of the Kalanchoe SHI-lines exhibited alterations in leaf colour or morphology, and most lines were not delayed in flowering Moreover, continuous treatment of lines delayed in flowering with low concentrations of gibberellins completely restored the time of flowering These features are very Important as a delay in flowering would increase plant production costs significantly. The effect of expression controlled by the native Arabidopsls SHI promoter was also investigated in transgenic Kalanchoe and resulted in plants with a longer flowering period Two AtSHI like genes were identified in Kalanchoe indicating a widespread presence of this transcription factor These findings are important because they suggest that transformation with the AtSHI gene could be applied to several species as a tool for growth retardation, and that this approach could substitute the use of conventional chemical growth regulation in plant productio

New discoveries at Woolsey Mound, MC118, northern Gulf of Mexico

Woolsey Mound, a 1km-diameter carbonate-gas hydrate complex in the northern Gulf of Mexico, is the site of the Gulf’s only seafloor monitoring station-observatory in its only research reserve, Mississippi Canyon 118. Active venting, outcropping hydrate, and a thriving chemosynthetic community recommend the site for study. Since 2005, the Gulf of Mexico Hydrates Research Consortium has been conducting multidisciplinary studies to 1. Characterize the site, 2. Establish a facility for real-time monitoring-observing of gas hydrates in a natural setting, 3. Study the effects of gas hydrates on seafloor stability, 4. Establish fluid migration routes and estimates of fluid-flux at the site, 5. Establish the interrelationships between the organisms at the vent site and the association-dissociation of hydrates. A variety of novel geological, geophysical, geochemical and biological studies has been designed and conducted, some in survey mode, others in monitoring mode. Geophysical studies involving merging multiple seismic data acquisition systems accompanied by the application of custom processing techniques verify communication of surface features with deep structures. Supporting geological data derive from innovative recovery techniques. Geochemical sensors, used experimentally in survey mode, including aboard an AUV, double as monitoring devices. A suite of pore-fluid sampling devices has returned data that capture change at the site in daily increments; using only noise as an energy source, hydrophones have returned daily fluctuations in physical properties. Ever-expanding capabilities of a custom-ROV have been determined by research needs. Processing of new as well as conventional data via unconventional means has resulted in the discovery of new features…..vents, faults, benthic fauna…..and modification of others including pockmarks, hydrate outcrops, vent activity, and water-column chemical plumes. Though real-time monitoring awaits communications and power link to land, periodic data-collection reveals a carbonate-hydrate mound, part of an immensely complex hydrocarbon system

Heterotic Weight Lifting

We describe a method for constructing genuinely asymmetric (2,0) heterotic strings out of N=2 minimal models in the fermionic sector, whereas the bosonic sector is only partly build out of N=2 minimal models. This is achieved by replacing one minimal model plus the superfluous E_8 factor by a non-supersymmetric CFT with identical modular properties. This CFT generically lifts the weights in the bosonic sector, giving rise to a spectrum with fewer massless states. We identify more than 30 such lifts, and we expect many more to exist. This yields more than 450 different combinations. Remarkably, despite the lifting of all Ramond states, it is still possible to get chiral spectra. Even more surprisingly, these chiral spectra include examples with a certain number of chiral families of SO(10), SU(5) or other subgroups, including just SU(3) x SU(2) x U(1). The number of families and mirror families is typically smaller than in standard Gepner models. Furthermore, in a large number of different cases, spectra with three chiral families can be obtained. Based on a first scan of about 10% of the lifted Gepner models we can construct, we have collected more than 10.000 distinct spectra with three families, including examples without mirror fermions. We present an example where the GUT group is completely broken to the standard model, but the resulting and inevitable fractionally charged particles are confined by an additional gauge group factor.Comment: 19 pages, 1 figur