Once more on θ\theta-vacua in 2+12+1 dimensional QED and 3+1 dimensional gluodynamics

Two different but tightly connected problems, $U(1)$ and strong CP violation problems, are discussed in two different models which exhibit both asymptotic freedom and confinement. One of them is the 3d Polyakov's model of compact QED and the other is 4d gluodynamics. It is shown that although both these models possess the long range interactions of the topological charges, only in the former case physics does not depend on $\theta$; while the latter exhibits an explicit $\theta$- dependence. The crucial difference is due to the observation, that the pseudoparticles of 4d gluodynamics possess an aditional quantum number, apart of the topological charge $Q$ .Comment: 15 page

The Frequent Items Problem in Online Streaming under Various Performance Measures

In this paper, we strengthen the competitive analysis results obtained for a fundamental online streaming problem, the Frequent Items Problem. Additionally, we contribute with a more detailed analysis of this problem, using alternative performance measures, supplementing the insight gained from competitive analysis. The results also contribute to the general study of performance measures for online algorithms. It has long been known that competitive analysis suffers from drawbacks in certain situations, and many alternative measures have been proposed. However, more systematic comparative studies of performance measures have been initiated recently, and we continue this work, using competitive analysis, relative interval analysis, and relative worst order analysis on the Frequent Items Problem.Comment: IMADA-preprint-c

An evaluation of the relative efficacy of an open airway, an oxygen reservoir and continuous positive airway pressure 5 cmH2O on the non-ventilated lung

Publisher's copy made available with the permission of the publisher © Australian Society of AnaesthetistsThe aim of this study, during one-lung ventilation, was to evaluate if oxygenation could be improved by use of a simple oxygen reservoir or application of 5 cmH2O continuous positive airway pressure (CPAP) to the non-ventilated lung compared with an open airway. Twenty-three patients with lung malignancy, undergoing thoracotomy requiring at least 60 minutes of one-lung ventilation before lung lobe excision, were studied. After routine induction and establishment of one-lung ventilation, the three treatments were applied in turn to the same patient in a sequence selected randomly. The first treatment was repeated as a fourth treatment and these results of the repeated treatment averaged to minimize the effect of slow changes. Arterial oxygenation was measured by an arterial blood gas 15 minutes after the application of each treatment. Twenty patients completed the study. Mean PaO2 (in mmHg) was 210.3 (SD 105.5) in the 'OPEN' treatment, 186.0 (SD 109.2) in the 'RESERVOIR' treatment, and 240.5 (SD 116.0) in the 'CPAP' treatment. This overall difference was not quite significant (P=0.058, paired ANOVA), but comparison of the pairs showed that there was a significant better oxygenation only with the CPAP compared to the reservoir treatments (t=2.52, P=0.021). While the effect on the surgical field was not apparent in most patients, in one patient surgery was impeded during CPAP. Our results show that the use of a reservoir does not give oxygenation better than an open tube, and is less effective than the use of CPAP 5 cmH2O on the non-ventilated lung during one-lung ventilation.J. Slimani, W. J. Russell, C. Jurisevichttp://www.aaic.net.au/Article.asp?D=200404

Fractons in Twisted Multiflavor Schwinger Model

We consider two-dimensional QED with several fermion flavors on a finite spatial circle. A modified version of the model with {\em flavor-dependent} boundary conditions $\psi_p(L) = e^{2\pi ip/ N} \psi_p(0)$, $p = 1, \ldots , N$ is discussed ($N$ is the number of flavors). In this case a non-contactable contour in the space of the gauge fields is {\em not} determined by large gauge transformations. The Euclidean path integral acquires the contribution from the gauge field configurations with fractional topological charge. The configuration with $\nu = 1/N$ is responsible for the formation of the fermion condensate $\langle\bar{\psi}_p \psi_p\rangle_0$. The condensate dies out as a power of $L^{-1}$ when the length $L$ of the spatial box is sent to infinity. Implications of this result for non-abelian gauge field theories are discussed in brief.Comment: 29 pages, 3 figures available upon request, Report TPI-MINN-94-24-T Plain LATE

Web similarity in sets of search terms using database queries

Normalized web distance (NWD) is a similarity or normalized semantic distance based on the World Wide Web or another large electronic database, for instance Wikipedia, and a search engine that returns reliable aggregate page counts. For sets of search terms the NWD gives a common similarity (common semantics) on a scale from 0 (identical) to 1 (completely different). The NWD approximates the similarity of members of a set according to all (upper semi) computable properties. We develop the theory and give applications of classifying using Amazon, Wikipedia, and the NCBI website from the National Institutes of Health. The last gives new correlations between health hazards. A restriction of the NWD to a set of two yields the earlier normalized Google distance (NGD), but no combina

Web similarity in sets of search terms using database queries

Normalized web distance (NWD) is a similarity or normalized semantic distance based on the World Wide Web or another large electronic database, for instance Wikipedia, and a search engine that returns reliable aggregate page counts. For sets of search terms the NWD gives a common similarity (common semantics) on a scale from 0 (identical) to 1 (completely different). The NWD approximates the similarity of members of a set according to all (upper semi)computable properties. We develop the theory and give applications of classifying using Amazon, Wikipedia, and the NCBI website from the National Institutes of Health. The last gives new correlations between health hazards. A restriction of the NWD to a set of two yields the earlier normalized google distance (NGD) but no combination of the NGD's of pairs in a set can extract the information the NWD extracts from the set. The NWD enables a new contextual (different databases) learning approachbased o

The cluster structure function

For each partition of a data set into a given number of parts there is a partition such that every part is as much as possible a good model (an "algorithmic sufficient statistic") for the data in that part. Since this can be done for every number between one and the number of data, the result is a function, the cluster structure function. It maps the number of parts of a partition to values related to the deficiencies of being good models by the parts. Such a function starts with a value at least zero for no partition of the data set and descents to zero for the partition of the data set into singleton parts. The optimal clustering is the one chosen to minimize the cluster structure function. The theory behind the method is expressed in algorithmic information theory (Kolmogorov complexity). In practice the Kolmogorov complexities involved are approximated by a concrete compressor. We give examples using real data sets: the MNIST handwritten digits and the segmentation of real cells as used in stem cell research