12 research outputs found
Motivations for the Soft Wall holographic approach to strong interactions
No full textThe hypothesis of gauge/gravity correspondence (or holographic duality) from
string theory has led to unexpected and challenging ways for description of
strongly coupled systems. Such descriptions are given in terms of
weakly-coupled higher-dimensional gravitational theories. The holographic ideas
have penetrated many branches of theoretical physics. We discuss motivations
for the so-called Soft Wall holographic approach to non-perturbative strong
interactions and its advantages.Comment: 6 pages; Contribution to XVIII International Conference on Symmetry
Methods in Physics, 10-16 July, 2022, Erevan, Armeni
Gluon string breaking and meson spectrum in the holographic Soft Wall model
No full textWe propose a general method for finding a string-like meson spectrum which is
based on a certain condition for the breaking of closed gluon string. A model
is constructed that successfully realizes the proposed method. The model is
based on the holographic Soft Wall model for QCD and the use of the Wilson
confinement criterion. We applied our approach to the vector and scalar cases
and obtained numerical predictions for the intercepts of corresponding Regge
like radial meson spectra. A good agreement is obtained both with the existing
experimental data and with some other known phenomenological approaches.
Remarkably, our closed string breaking condition has two branches. We argue
that they should correspond to states of opposite parity. The Wilson
confinement criterion leads then to a natural mass splitting between parity
partners. The constructed model represents thus the first example of bottom-up
holographic model in which the effects of chiral symmetry breaking can emerge
automatically, i.e., without additional assumptions taken outside of the
holographic approach.Comment: 18 pages, 5 figures, v2: matches version published in PL
Confinement potential in Soft Wall holographic approach to QCD
No full textWe present the results for the confinement potential of the Cornell type
within the framework of the generalized Soft Wall holographic model (with
quadratic dilaton background in the metric) which contains an additional
parameter responsible for the value of intercept of the linear Regge spectrum.
Next, we note that the Cornell potential arises also in some Soft Wall models
which do not lead to Regge-like spectrum. As an example, we demonstrate this
property in a model with linear dilaton background in the metric. This example
is at odds with intuition based on the hadron string picture that the linearly
rising potential and Regge-like spectrum are directly related.Comment: 6 pages, contribution to the International Conference on Quantum
Field Theory, High-Energy Physics, and Cosmology (Dubna, Russian Federation,
July 2022
Confinement Potential in a Soft-Wall Holographic Model with a Hydrogen-like Spectrum
No full textIt is well known that the soft-wall holographic model for QCD successfully reproduces not only the linear Regge spectrum, but also, via the holographic Wilson confinement criterion, the “linear plus Coulomb” confinement potential, which is similar to the Cornell potential. This property could be interpreted as a holographic counterpart of the hadron string picture, where the linearly rising potential and Regge-like spectrum are directly related. However, such a relation does not exist in the bottom-up holographic approach. Namely, the Cornell-like potentials arise in a broad class of bottom-up holographic models. The standard soft-wall model is merely a particular representative of this class. This fact is relatively unknown, so we provide a comprehensive discussion of the point. As an example, we consider a soft-wall-like model with linear dilaton background in the metric. This model leads to a hydrogen-like spectrum. A “linear plus Coulomb” confinement potential within this model is calculated. The calculation of renormalized potential at short distances turns out to be complicated by a new subtlety that was skipped in general discussions of the issue existing in the literature. However, the confinement potential of the model is shown to be not very different from the potential obtained in the standard soft-wall model with a quadratic background
Cooperation of preschool teachers and parents for improvement of the emotional development of children of preschool age
No full textDarba autors - Veronika Isakova – Solomko Kvalifikācijas darba tēma - Pirmsskolas pedagogu un vecāku sadarbība bērna emocionālās attīstības pilnveidei pirmsskolā Darba vadītājs – Dr. Psych. Tija Zīriņa Darba veids - kvalifikācijas darbs studiju programmā – Pirmsskolas izglītības skolotājs Darba mērķis - teorētiski izzināt un praktiski pārbaudīt bērna emocionālo attīstības pilnveidei PII pedagogu un vecāku sadarbības rezultātā Darbs sastāv no divām daļām: teorētiskās un praktiskās. Teorētiskajā daļā tika sniegtas atziņas, izmantota pedagoģiskā, psiholoģiskā literatūra, apraksti par bērnu emocijām un jūtām, to attīstību, par vecāku un pirmskolas izglītības iestādes skolotāju sadarbības formām, metodēm, to pilnveidi un nozīmi. Praktiskajā daļā tika veikti pirmsskolas 4-5 gadu vecuma bērnu emociju un jūtu izpausmju novērojumi un veiktas pedagoģiskās izmēģinājumdarbības, vecāku un pedagogu anketēšana, kas veicina vecāku un pirmskolas izglītības iestādes skolotāju sadarbības pilnveidi. Apkopojot pētījuma rezultātus, darba autore secina, ka bērnu emocionālās attīstības veicināšana var notikt sekmīgāk, ja ir ļoti cieša, uzticēšanās pilna un mērķtiecīga sadarbība bērnu vecākiem un pedagogiem. Pētījumā gaitā apstiprinājās izvirzītais jautājums - kā PII pedagogu un vecāku sadarbība pilnveido bērnu emocionālo attīstību - darba autorei ir sniedzis daudzas atbildes. Darba apjoms: Darbs sastāv no 33 attēliem, 4 tabulām, 47 literatūras avotiem, 10 pielikumiem. Darba apjoms ir 53 lapaspuses.Author of the work: Veronika Isakova-Solomko Subject of qualification work: Co-operation of Pre-School Teachers and Parents for Improvement of Emotional Development of a Child in Pre-School Scientific Head of Labor: Dr. Psych. Tija Zīriņa The work consists of the qualification work in the study programme: Pre-School Education Teacher Objective of the work: To theoretically understand and practically test the emotional development of a child for the improvement of the development of pre-school education institutions (PII) as a result of co-operation between teachers and parents. The work consists of two parts: Theoretical and Practical. In the theoretical part: Lessons were provided, pedagogical and psychological literature was used, descriptions of children's emotions and feelings were examined, including their development, the forms, methods, improvement, and significance of cooperation between parents and teachers in pre-school educational institutions. In the practical part: Observations of emotions and expressions of feelings of pre-school children aged 4-5 were made, and pedagogical trials were conducted. Questionnaires were administered to parents and educators to promote the improvement of cooperation between teachers and parents in pre-school educational institutions. Summarising the results of the study, the author concludes that promoting children's emotional development can be more successful if there is very close, trust-filled, and focused collaboration among parents and educators. Over the course of the study: The question raised - how collaboration between pre-school educators and parents improves children's emotional development - has been addressed with many answers by the author. Working components: The work consists of 33 images, 4 tables, 47 literature sources, and 10 attachments. The total amount of work is 53 pages
Dark matter production via a non-minimal coupling to gravity
No full textInternational audienceWe study postinflationary scalar dark matter production via its non-minimal coupling to gravity. During the inflaton oscillation epoch, dark matter is produced resonantly for a sufficiently large non-minimal coupling . We find that backreaction on the curvature and rescattering effects typically become important for the values of above , which invalidate simple estimates of the production efficiency. At large couplings, the dark matter yield becomes almost independent of , signifying approximate quasi-equilibrium in the inflaton-dark matter system. Although the analysis gets complicated by the presence of apparent negative energy in the Jordan frame, this behaviour can be regularized by introducing mild dark matter self-interaction. Using lattice simulations, we delineate parameter space leading to the correct dark matter relic abundance
Inflaton freeze-out
No full textWe study the possibility that, after inflation, the inflaton reaches thermal
equilibrium with the Standard Model thermal bath and eventually freezes-out in
the non-relativistic regime. When the inflaton decay is the sole source of
(non-thermal) dark matter, its relic density is automatically suppressed. We
delineate parameter space leading to the correct dark matter abundance. The
model allows for a significant Higgs-inflaton coupling which may lead to
invisible Higgs decay into inflaton pairs at the LHC.Comment: 14 pages, 3 figures; v2: matches version published in PRD (extended
discussions, fixed typos, updated references
Islam in the United States of America: cultural and political aspects
No full textBakalaura darba tēma ir „Islāms Amerikas Savienotajās Valstīs: kultūras un politikas aspekti”.
Darbs ietver piecas daļas, ievadu, nobeigumu un tiek piedāvāts arī izmantotās literatūras saraksts.
Ievadā uzstādīti darba mērķi un uzdevumi.
Pirmās daļas sadaļas sniedz informāciju par islāma vēsturi,
Otrajā daļā tiek izklāstīta islāma vēsture ASV.
Trešajā daļā paradīti teroristiskas organizācijas, kas darbojas ASV, situācijas izmaiņas pēc 2001. gada 11. septembra traģiskiem notikumiem.
Ceturtajā daļā izklāstīta, demogrāfiskā situācija, amerikāņu musulmaņu kultūras un reliģiozie aspekti, to ietekme uz valsts politiku,.
Piektajā daļā apskatīta musulmaņu loma politiskajā dzīvē. Šodienas politiskais stāvoklis pēc jaunā prezidenta Baraka Obamas nākšanas pie varas.
Līdz ar zinātniskiem un publicistiskiem avotiem darbā izmantoti arī Rīgas U.S. Informatīvu Centru piedāvātie materiāli.
Pētījuma rezultāti tika izanalizēti un darbā precizēti diagrammās, aprakstos, kartēs.
Autors ir devis atsauces uz avotiem, kas izmantoti darbam.
Autors cer, ka šīs darbs paplašinās priekšstatu par islāmu, tādā lielā valstī kā ASV.The theme of the graduation work is “Islam in the United States of America: cultural and political aspects”.
The structure of the paper contains introduction, five content parts, and conclusion, also a description of the used literature given.
The introduction set the goals and objectives of this work.
In the first part shortly viewed the history of Islam civilization.
Second part shows the history of Islam in the United States.
The third part is about, terrorist’s organizations, and the changing situation with regard to the tragic events of September 11, 2001.
Fourth part presented demographic situation, cultural and religious aspects of American Muslims.
And the final fifth part is about Muslim role in the political life of the United States. Also about the politic of the new president Barack Obama
In addition to the scientific, journalistic sources, web – sites and materials provided by Riga` s U. S. Information Center.
The results of the researches have been analyzed and are presented in the form of diagrams, descriptions, maps.
The author gives references to the literature used in the paper.
The author hopes that his work will enhance the image of Islam, particularly in large countries such as the United States
Dark matter production and reheating via direct inflaton couplings : collective effects
No full textWe study scalar dark matter production and reheating via renormalizable inflaton couplings, which include both quartic and trilinear interactions. These processes often depend crucially on collective effects such as resonances, backreaction and rescattering of the produced particles. To take them into account, we perform lattice simulations and map out parameter space producing the correct (non-thermal) dark matter density. We find that the inflaton-dark matter system can reach a quasi-equilibrium state during preheating already at very small couplings, in which case the dark matter abundance becomes independent of the inflaton-dark matter coupling and is described by a universal formula. Dark matter is readily overproduced and even tiny values of the direct inflaton couplings can be sufficient to get the right composition of the Universe, which reaffirms their importance in cosmology.Peer reviewe
Rule of Law vs. Law archaization: the question concerning the particularity of Law’s form in peripheral dependent capitalism
No full texthttps://doi.org/10.1590/2179-8966/2024/87726
The subject of this research is the phenomenon of archaization of legal form, which is reflected multiple modern legal systems, including the legal system of modern Russia. The author believes that the state of current Russian legal order testifies to the downfall of one of the declared goals of Russia’s policy of the last three decades – establishment of the so-called rule of law; while the general academic theory of law has not yet formulated a precise understanding of the corresponding processes, as fearing to go beyond the scope of certain ideological boundaries, it first and foremost deals with the formally due than with actually essential. Archaization in the legal systems of modern countries is the revival of the forms of law, legal practice and legal consciousness that are inherent to the pre-capitalist societies. The thesis is substantiated that the process of archaization of law and legal form as a whole, should be considered as one of the objectively determined development patterns and functionality of the societies of dependent peripheral capitalism. The article reviews the objective prerequisites for this phenomenon: its conditionality by socioeconomic relations (preservation of the elements of other production methods in terms of peripheral capitalism), inequality in distribution of the key social resources, and specific social-class structure of the corresponding societies. The general definition of archaization of legal form acquires more precise contours when the author turns to the realities of modern Russian legal order.https://doi.org/10.1590/2179-8966/2024/87726
O objeto de pesquisa é o fenômeno da arcaização da forma jurídica, que se revela em muitos sistemas jurídicos contemporâneos, incluindo o da Rússia de hoje. O estado da ordem jurídica russa atual indica o colapso de um dos objetivos declarados da política russa das últimas três décadas: a construção do assim chamado estado de direito. A teoria geral do direito acadêmica ainda não elaborou uma compreensão concreta dos processos correspondentes, na medida em que, temendo ultrapassar certas fronteiras ideológicas, ocupa-se principalmente com um dever-ser formalmente abstrato, e não com o concreto realmente existente. A arcaização nos sistemas jurídicos dos países contemporâneos é o renascimento de formas de direito, de prática jurídica e de consciência jurídica que são inerentes às sociedades pré-capitalistas. Fundamenta-se a tese de que o processo de arcaização do direito e da forma jurídica como um todo deve ser entendido como uma das regularidades objetivamente determinadas de desenvolvimento e de funcionamento das sociedades do capitalismo periférico dependente. O artigo examina os pré-requisitos objetivos desse fenômeno: seu condicionamento por relações socioeconômicas (preservação de elementos de outros modos de produção sob o capitalismo periférico), a desigualdade na distribuição de recursos sociais essenciais e a estrutura de classe social específica das correspondentes sociedades. O conceito geral de arcaização da forma jurídica assume contornos mais específicos quando a autora se volta à realidade da ordem jurídica russa contemporânea
