Search results for "THEORIE"
showing 10 items of 354 documents
Causal representation of multi-loop Feynman integrands within the loop-tree duality
2021
The numerical evaluation of multi-loop scattering amplitudes in the Feynman representation usually requires to deal with both physical (causal) and unphysical (non-causal) singularities. The loop-tree duality (LTD) offers a powerful framework to easily characterise and distinguish these two types of singularities, and then simplify analytically the underling expressions. In this paper, we work explicitly on the dual representation of multi-loop Feynman integrals generated from three parent topologies, which we refer to as Maximal, Next-to-Maximal and Next-to-Next-to-Maximal loop topologies. In particular, we aim at expressing these dual contributions, independently of the number of loops an…
Higgs production in a warped extra dimension
2012
Measurements of the Higgs-boson production cross section at the LHC are an important tool for studying electroweak symmetry breaking at the quantum level, since the main production mechanism gg → h is loop-suppressed in the Standard Model (SM). Higgs production in extra-dimensional extensions of the SM is sensitive to the Kaluza-Klein (KK) excitations of the quarks, which can be exchanged as virtual particles in the loop. In the context of the minimal Randall-Sundrum (RS) model with bulk fields and a brane-localized Higgs sector, we derive closed analytical expressions for the gluon-gluon fusion process, finding that the effect of the infinite tower of virtual KK states can be described in …
Twistor string as tensionless superstring
2007
6 pages.-- PACS nrs.: 11.30.Pb, 11.25.-w, 11.10.Kk, 12.60.Jv.-- ISI Article Identifier: 000247103400009.-- ArXiv pre-print available at: http://arxiv.org/abs/hep-th/0702133
Consistent QFT description of non-standard neutrino interactions
2019
Neutrino oscillations are precision probes of new physics beyond the Standard Model. Apart from neutrino masses and mixings, they are also sensitive to possible deviations of low-energy interactions between quarks and leptons from the Standard Model predictions. In this paper we develop a systematic description of such non-standard interactions (NSI) in oscillation experiments within the quantum field theory framework. We calculate the event rate and oscillation probability in the presence of general NSI, starting from the effective field theory (EFT) in which new physics modifies the flavor or Lorentz structure of charged-current interactions between leptons and quarks. We also provide the…
Correlation patterns from massive phonons in 1+1 dimensional acoustic black holes: A toy model
2018
Transverse excitations in analogue black holes induce a mass like term in the longitudinal mode equation. With a simple toy model we show that correlation functions display a rather rich structure characterized by groups of parallel peaks. For the most part the structure is completely different from that found in the massless case.
Die Embryologie im Spannungsfeld zwischen Tradition und Empirie.
1991
Already in classical antiquity people dealt with the principle of formation, developing different theories. Researchers in the renaissance, working in the conflict zone between tradition and experience, tried to prove one or the other of these theories by the means of new observations, especially of chicken development. Aldrovandi was the first to see the real principle of formation of the hen's egg, i. e. the blastodisc, but he didn't recognize the importance of his discovery due to his close adherence to Aristotle in the theoretical field. Fabricius even thought that traditional knowledge was of more importance than his own excellent observations. Parisano was the first to succeed in maki…
Romanians’ current perception of threat from immigrants in a context of co-ethnic migration: assessing the role of intergroup conflict and active/pas…
2017
AbstractThis paper investigates the predictors of natives’ perception of the immigrant threat in Romania, an interesting site given immigrants’ marginal presence in the total population and the sizeable proportion of co-ethnic immigrants. Yet the interplay between nationalism and religion shapes an ideological frame that favours unwelcoming attitudes towards immigrants that challenge the Romanian identity forged along ethnic and religious ties. The authors used regression to analyse immigrant threat according to several dimensions: cosmopolitanism, group conflict and intergroup contact. In order to reflect specificities of this particular context, the latter dimension is conceptualized so a…
Inflation might be caused by the right
2009
15 pages, 4 figures.-- ISI article identifier: 000265600800102.-- ArXiv pre-print avaible at: http://arxiv.org/abs/0811.2998
Using stage theorizing to make anti-phishing recommendations more effective
2018
Purpose This paper aims to review the behavioral phishing literature to understand why anti-phishing recommendations are not very effective and to propose ways of making the recommendations more effective. The paper also examines how the concept of stages from health communication and psychology can be used to make recommendations against phishing more effective. Design/methodology/approach This literature review study focused on the behavioral phishing literature that has relied on human subjects. Studies were excluded for reasons that included lacking practical recommendations and human subjects. Findings The study finds that phishing research does not consider where victims are residing…