Loop constraints: A habitat and their algebra

This work introduces a new space \T'_* of `vertex-smooth' states for use in the loop approach to quantum gravity. Such states provide a natural domain for Euclidean Hamiltonian constraint operators of the type introduced by Thiemann (and using certain ideas of Rovelli and Smolin). In particular, such operators map \T'_* into itself, and so are actual operators in this space. Their commutator can be computed on \T'_* and compared with the classical hypersurface deformation algebra. Although the classical Poisson bracket of Hamiltonian constraints yields an inverse metric times an infinitesimal diffeomorphism generator, and despite the fact that the diffeomorphism generator has a well-defined non-trivial action on \T'_*, the commutator of quantum constraints vanishes identically for a large class of proposals.Comment: 30 pages RevTex, 2 figures include

Ład akademicki w krajach Unii Europejskiej, Stanach Zjednoczonych i Polsce

 “Academic governance” is a term which is little known and rarely used in Polish literaturę. However, this term is essential to understand the extensive literaturę on higher education reforms and models published in various countries. When discussing academic governance Solutions, Polish literaturę usually uses the term system (system) to refer to the external environment of universities and the term ustrój (internal organisation) to talk about Solutions within universities. In the first part of his paper, the author defines the notions of academic governance, external academic governance and internal academic governance and then discusses academic governance Solutions in the European Union, English-speaking countries (example of the USA) and in Poland. While in 1960s the European reforms of academic governance were inspired by public governance, the governance structures in the private sector have become the model in recent years. Research confirms that the changes in governance are heading, albeit falteringly, towards an increased marketisation of the European higher education. In Poland, the marketisation of the education system has meant, above all, the emergence of the non-public sector alongside a non-market system, the latter persisting in the public higher education sector. Ład akademicki (academic governance) to termin mato znany i rzadko używany  w polskiej literaturze przedmiotu. Bez jego wprowadzenia trudno jednak czerpać  z dorobku bogatej literatury światowej na temat reform i modeli szkolnictwa wyższego.  W polskiej literaturze przy omawianiu rozwiązań dotyczących ładu akademickiego  w zewnętrznym otoczeniu uczelni używa się zwykle terminu „system”, jeśli natomiast  omawia się rozwiązania wewnątrz uczelni, stosuje się zazwyczaj termin „ustrój”.  W pierwszej części artykułu autor definiuje pojęcia „ład akademicki” oraz „zewnętrzny  ład akademicki” i „wewnętrzny ład akademicki”, w następnych omawia rozwiązania  w dziedzinie ładu akademickiego w Unii Europejskiej, w krajach anglosaskich  (na przykładzie Stanów Zjednoczonych) oraz w Polsce.  Podczas gdy w latach sześćdziesiątych )0( w. europejskie reformy ładu akademickiego  czerpały inspirację z ładu publicznego, to obecnie wzorcem są struktury  zarządzania w sektorze prywatnym. Wyniki badań potwierdzają, że zmiany sterowania  systemu idą, choć niepewnym krokiem, w kierunku większego urynkowienia  europejskiego obszaru szkolnictwa wyższego. W Polsce urynkowienie systemu  szkolnictwa jak dotąd polegało głównie na stworzeniu sektora szkół niepublicznych,  z jednoczesnym zachowaniem systemu nierynkowego w publicznym sektorze  szkolnictwa wyższego

Ab initio electronic structure calculations of solid, solution-processed metallotetrabenzoporphyrins

An ab initio study of the electronic structures of solid metallotetrabenzoporphyrins (MTBPs) utilized in organic transistors and photovoltaics is presented. Bandstructures, densities of states, and orbitals are calculated for H2, Cu, Ni, and Zn core substitutions of the unit cell of solid TBP, as deposited via soluble precursors that are thermally annealed to produce polycrystalline, semiconducting thin-films. While the unit cells of the studied MTBPs are nearly isomorphous, substitution of the core atoms alters the structure of the bands around the energy bandgap and the composition of the densities of states. Cu and Ni core substitutions introduce nearly-dispersionless energy bands near the valence and conduction band edges, respectively, that form acceptor or deep generation/recombination states.Comment: 7 pages, 3 figures, 4 table

Next-Generation Sequencing — An Overview of the History, Tools, and “Omic” Applications

Next-generation sequencing (NGS) technologies using DNA, RNA, or methylation sequencing have impacted enormously on the life sciences. NGS is the choice for large-scale genomic and transcriptomic sequencing because of the high-throughput production and outputs of sequencing data in the gigabase range per instrument run and the lower cost compared to the traditional Sanger first-generation sequencing method. The vast amounts of data generated by NGS have broadened our understanding of structural and functional genomics through the concepts of “omics” ranging from basic genomics to integrated systeomics, providing new insight into the workings and meaning of genetic conservation and diversity of living things. NGS today is more than ever about how different organisms use genetic information and molecular biology to survive and reproduce with and without mutations, disease, and diversity within their population networks and changing environments. In this chapter, the advances, applications, and challenges of NGS are reviewed starting with a history of first-generation sequencing followed by the major NGS platforms, the bioinformatics issues confronting NGS data storage and analysis, and the impacts made in the fields of genetics, biology, agriculture, and medicine in the brave, new world of ”omics.

2-Group Representations for Spin Foams

Just as 3d state sum models, including 3d quantum gravity, can be built using categories of group representations, "2-categories of 2-group representations" may provide interesting state sum models for 4d quantum topology, if not quantum gravity. Here we focus on the "Euclidean 2-group", built from the rotation group SO(4) and its action on the group of translations of 4d Euclidean space. We explain its infinite-dimensional unitary representations, and construct a model based on the resulting representation 2-category. This model, with clear geometric content and explicit "metric data" on triangulation edges, shows up naturally in an attempt to write the amplitudes of ordinary quantum field theory in a background independent way.Comment: 8 pages; to appear in proceedings of the XXV Max Born Symposium: "The Planck Scale", Wroclaw, Polan

Casimir energy of Sierpinski triangles

Using scaling arguments and the property of self-similarity we derive the Casimir energies of Sierpinski triangles and Sierpinski rectangles. The Hausdorff-Besicovitch dimension (fractal dimension) of the Casimir energy is introduced and the Berry-Weyl conjecture is discussed for these geometries. We propose that for a class of fractals, comprising of compartmentalized cavities, it is possible to establish a finite value to the Casimir energy even while the Casimir energy of the individual cavities consists of divergent terms.Comment: 7 pages, 5 figures, minor typos correcte

How to evaluate cross-sections in models where the S-matrix is unitary but does not conserve energy

The standard time-dependent description of the scattering processes is used to explain that, when the S-matrix does not conserve energy, the coefficient relating the squared modulus of the S-matrix element to the cross-section becomes model-dependent, and the optical theorem does not necessarily follow from the unitarity of the S-matrix. It is suggested that, if one insists on using such models, the optical theorem should be imposed as a constraint and used to fix the model-dependent coefficient

Thermodynamics and two-dimensional lattice Gauge models

he gauge theory with the gauge group U(N $\to \infty$) is solved on a two-dimensional lattice. The single plaquette action used depends on L parameters, where L is an arbitrary integer, and thus results for a wide class of variant actions may be compared. A rich structure of second order and third order phase transitions appears. Besides the exact analytic solution a thermodynamical discussion clarifying the qualitative features of the results is given

Anatomical aspects of epidural and spinal analgesia

Regional anaesthesia seems to be the future of the anaesthesia in this century. The knowledge of the anatomy of the epidural and other spinal spaces seems to play the crucial role in success of regional anaesthesia. It's important in perioperative medicine and cancer pain treatment. Up to date there is not too many datas considering anatomy of these compartments. Many of the results obtained by researchers in the past are still not mentioned in the clinical textbooks. This article is an attempt to resolve this problem.Regional anaesthesia seems to be the future of the anaesthesia in this century. The knowledge of the anatomy of the epidural and other spinal spaces seems to play the crucial role in success of regional anaesthesia. It's important in perioperative medicine and cancer pain treatment. Up to date there is not too many datas considering anatomy of these compartments. Many of the results obtained by researchers in the past are still not mentioned in the clinical textbooks. This article is an attempt to resolve this problem

A further algebraic version of Cochran's theorem and matrix partial orderings

AbstractA new version of Cochran's theorem for rectangular matrices is established. Being oriented toward partial isometries, the new version parallels corresponding results concerned with arbitrary tripotent matrices and covers results concerned with Hermitian tripotent matrices. A discussion of a related new matrix partial ordering is also given