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11.
V. K. Oikonomou 《Theoretical and Mathematical Physics》2009,159(1):509-525
We study the temperature inversion symmetry R → 1/T for the finite-temperature effective potential of the N=1, d=5 supersymmetric SU(3)
c
×SU(3)
w
model on the orbifold S
1
/Z
2
. For the value of the Wilson line parameter α = 1 (SU(2)
L
breaks to U′(1)), we show that the effective potential contains a symmetric part and an antisymmetric part under ξ → 1/ξ, ξ = RT. For α = 0 (SU(2)
L
is preserved in this case), we find that the only contribution to the effective potential that breaks the temperature inversion
symmetry comes from the fermions in the fundamental representation of the gauge group with the Z
2
parities (+, +) or (−,−). This is interesting because it implies that the bulk effective potential corresponding to models
with fundamental fermions localized at a fixed point in the orbifold (and models with no bulk fundamental fermions) has the
temperature inversion symmetry.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 159, No. 1, pp. 109–130, April, 2009. 相似文献
12.
We use q-exponential distributions, which maximize the nonextensive entropy Sq (defined as ), to study the size distributions of non-coding DNA (including introns and intergenic regions) in all human chromosomes. We show that the value of the exponent q describing the non-coding size distributions is similar for all chromosomes and varies between 2≤q≤2.3 with the exception of chromosomes X and Y. 相似文献
13.
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15.
In this article we study in detail the supersymmetric structures that underlie the system of fermionic zero modes around a superconducting cosmic string. Particularly, we extend the analysis existing in the literature on the one dimensional N=2 supersymmetry and we find multiple N=2, d=1 supersymmetries. In addition, compact perturbations of the Witten index of the system are performed and we find to which physical situations these perturbations correspond. More importantly, we demonstrate that there exists a much more rich supersymmetric structure underlying the system of fermions with Nf flavors and these are N-extended supersymmetric structures with non-trivial topological charges, with “N” depending on the fermion flavors. 相似文献
16.
D. Sokaras A. G. Karydas A. Oikonomou N. Zacharias K. Beltsios V. Kantarelou 《Analytical and bioanalytical chemistry》2009,395(7):2199-2209
Ion beam analysis (IBA)- and X-ray fluorescence (XRF)-based techniques have been well adopted in cultural-heritage-related
analytical studies covering a wide range of diagnostic role, i.e., from screening purposes up to full quantitative characterization.
In this work, a systematic research was carried out towards the identification and evaluation of the advantages and the limitations
of laboratory-based (IBA, electron probe microanalyzer) and portable (milli-XRF and micro-XRF) techniques. The study focused
on the analysis of an Archaic glass bead collection recently excavated from the city of Thebes (mainland, Greece), in order
to suggest an optimized and synergistic analytical methodology for similar studies and to assess the reliability of the quantification
procedure of analyses conducted in particular by portable XRF spectrometers. All the employed analytical techniques and methodologies
proved efficient to provide in a consistent way characterization of the glass bead composition, with analytical range and
sensitivity depending on the particular technique. The obtained compositional data suggest a solid basis for the understanding
of the main technological features related to the raw major and minor materials utilized for the manufacture of the Thebian
ancient glass bead collection. 相似文献
17.
By only requiring the q deformed logarithms (q exponentials) to possess arguments chosen from the entire set of positive real numbers (all real numbers), we show that the q-logarithm (q exponential) can be written in such a way that its argument varies between 0 and 1 (among negative real numbers) for 1?q<2, while the interval 0<q?1 corresponds to any real argument greater than 1 (positive real numbers). These two distinct intervals of the nonextensivity index q, also the expressions of the deformed functions associated with them, are related to one another through the relation (2−q), which is so far used to obtain the ordinary stationary distributions from the corresponding escort distributions, and vice versa in an almost ad hoc manner. This shows that the escort distributions are only a means of extending the interval of validity of the deformed functions to the one of ordinary, undeformed ones. Moreover, we show that, since the Tsallis entropy is written in terms of the q-logarithm and its argument, being the inverse of microstate probabilities, takes values equal to or greater than 1, the resulting stationary solution is uniquely described by the one obtained from the ordinary constraint. Finally, we observe that even the escort stationary distributions can be obtained through the use of the ordinary averaging procedure if the argument of the q-exponential lies in (−∞,0]. However, this case corresponds to, although related, a different entropy expression than the Tsallis entropy. 相似文献
18.
Spiros Kostopoulos Konstantinos Sidiropoulos Dimitris Glotsos Emmanouil Athanasiadis Konstantina Boutsikou Eleftherios Lavdas Georgia Oikonomou Ioannis V. Fezoulidis Marianna Vlychou Michael Hantes Dionisis Cavouras 《Magnetic resonance imaging》2013
The aim was to design a pattern-recognition (PR) system for discriminating between normal and pathological knee articular cartilage of the medial femoral (MFC) and tibial condyles (MTC). The data set comprised segmented regions of interest (ROIs) from coronal and sagittal 3-T magnetic resonance images of the MFC and MTC cartilage of young patients, 28 with abnormality-free knee and 16 with pathological findings. The PR system was designed employing the probabilistic neural network classifier, textural features from the segmented ROIs and the leave-one-out evaluation method, while the PR system's precision to “unseen” data was assessed by employing the external cross-validation method. Optimal system design was accomplished on a consumer graphics processing unit (GPU) using Compute Unified Device Architecture parallel programming. PR system design on the GPU required about 3.5 min against 15 h on a CPU-based system. Highest classification accuracies for the MFC and MTC cartilages were 93.2% and 95.5%, and accuracies to “unseen” data were 89% and 86%, respectively. The proposed PR system is housed in a PC, equipped with a consumer GPU, and it may be easily retrained when new verified data are incorporated in its repository and may be of value as a second-opinion tool in a clinical environment. 相似文献
19.
Good Michael R. R. Temirkhan Maksat Oikonomou Thomas 《International Journal of Theoretical Physics》2019,58(9):2942-2968
A worldline with a time-independent spectrum is called stationary. Such worldlines are arguably the most simple motions in physics. Barring the trivially static motion, the non-trivial worldlines are uniformly accelerated. As such, a point charge moving along a stationary worldline will emit constant radiative power. The angular distribution, maximum angle scaling and Thomas precession of this power is found for all stationary worldlines including those with torsion and hypertorsion.
相似文献20.
V.K. Oikonomou 《Nuclear Physics B》2012,856(1):1-25
The localized fermions on the intersection curve Σ of D7-branes, are connected to a N=2 supersymmetric quantum mechanics algebra. Due to this algebra the fields obey a global U(1) symmetry. This symmetry restricts the proton decay operators and the neutrino mass terms. Particularly, we find that several proton decay operators are forbidden and the Majorana mass term is the only one allowed in the theory. A special SUSY QM algebra is studied at the end of the paper. In addition we study the impact of a non-trivial holomorphic metric perturbation on the localized solutions along each matter curve. Moreover, we study the connection of the localized solutions to an N=2 supersymmetric quantum mechanics algebra when background fluxes are turned on. 相似文献