scholarly journals Relativistic spin sum rules and the role of the pivot

2021 ◽  
Vol 81 (5) ◽  
Author(s):  
Cédric Lorcé
Keyword(s):  
Angular Momentum ◽  
Phase Space ◽  
Relativistic Theory ◽  
Sum Rules ◽  
Spin Component ◽  
Sum Rule ◽  
Relativistic Spin ◽  
First Time ◽  
Space Approach

AbstractSpin sum rules depend on the choice of a pivot, i.e. the point about which the angular momentum is defined, usually identified with the center of the nucleon. The latter is however not unique in a relativistic theory and has led to apparently contradictory results in the literature. Using the recently developed phase-space approach, we compute for the first time the contribution associated with the motion of the center of the nucleon, and we derive a general spin sum rule which reduces to established results after appropriate choices for the pivot and the spin component.

scholarly journals ON THE QCD SUM RULE DETERMINATION OF THE STRANGE QUARK MASS

2001 ◽  
Vol 16 (supp01b) ◽  
pp. 588-590 ◽  
Author(s):  
NELLO PAVER
Keyword(s):  
Spectral Function ◽  
Quark Mass ◽  
Strange Quark ◽  
Sum Rules ◽  
Sum Rule ◽  
Strange Quark Mass ◽  
Current Quark Mass ◽  
Current Quark

I briefly review recent QCD Sum Rules determinations of the strange current quark mass, based on the analysis of the two-point ΔS=1 scalar correlators and discuss, in particular, the role of resonances and non-resonant background in the spectral function.

Experimental Observation of Chaotic Beats in Oscillators Sharing Nonlinearity

2016 ◽  
Vol 26 (10) ◽  
pp. 1630027 ◽  
Author(s):  
M. Paul Asir ◽  
A. Jeevarekha ◽  
P. Philominathan
Keyword(s):  
Phase Space ◽  
Experimental Observation ◽  
Time Domain ◽  
Hardware Implementation ◽  
Nonlinear Element ◽  
State Variables ◽  
Chaotic Beats ◽  
Chaotic Nature ◽  
First Time

This paper deals with the generation of chaotic beats in a system of two forced dissipative LCR oscillators sharing a nonlinear element. The presence of two external periodic excitations and a common nonlinear element in the chosen system enables the facile generation of chaotic beats. Thus rendered chaotic beats were characterized in both time domain and phase space. Lyapunov exponents and envelope of the beats were computed to diagnose the chaotic nature of the signals. The role of common nonlinearity on the complexity of the generated beats is discussed. Real-time experimental hardware implementation has also been done to confirm the subsistence of the phenomenon, for the first time. Extensive Multisim simulations were carried out to understand, a bit more about the shrinkage and revivals of state variables in phase space.

scholarly journals SUM-RULE CONSTRAINTS FOR OPEN MESOSCOPIC CONDUCTORS

2004 ◽  
Vol 18 (10n11) ◽  
pp. 1479-1488 ◽  
Author(s):  
JAGDISH S. THAKUR ◽  
FREDERICK GREEN ◽  
MUKUNDA P. DAS
Keyword(s):  
Electronic Transport ◽  
Sum Rules ◽  
Electron Gas ◽  
Length Scale ◽  
Consistency Check ◽  
Sum Rule ◽  
Nonequilibrium Transport ◽  
Mesoscopic Conductors

The conserving sum rules for the electron gas form a set of fundamental and powerful constraints on the description of electronic transport, at any length scale. We examine the particular role of the compressibility sum rule for open mesoscopic conductors, and show that the compressibility in such systems is absolutely invariant under nonequilibrium transport. The compressibility sum rule provides a stringent consistency check on models of mesoscopic conduction.

scholarly journals Critique of the angular momentum sum rules and a new angular momentum sum rule

2004 ◽  
Vol 70 (11) ◽  
Author(s):  
B. L. G. Bakker ◽  
E. Leader ◽  
T. L. Trueman
Keyword(s):  
Angular Momentum ◽  
Sum Rules ◽  
Sum Rule

scholarly journals Radiative decays of heavy-light mesons and the $$ {f}_{H,{H}^{\ast },{H}_1}^{(T)} $$ decay constants

2021 ◽  
Vol 2021 (9) ◽  
Author(s):  
Ben Pullin ◽  
Roman Zwicky
Keyword(s):  
Sum Rules ◽  
Form Factors ◽  
Radiative Decays ◽  
Matrix Elements ◽  
Leading Order ◽  
Sum Rule ◽  
Decay Constants ◽  
Leptonic Decays ◽  
Shell Matrix ◽  
First Time

Abstract The on-shell matrix elements, or couplings $$ {g}_{H{H}^{\ast}\left({H}_1\right)\upgamma} $$ g H H ∗ H 1 γ , describing the $$ B{(D)}_q^{\ast } $$ B D q ∗ → B(D)qγ and B1q → Bqγ (q = u, d, s) radiative decays, are determined from light-cone sum rules at next-to-leading order for the first time. Two different interpolating operators are used for the vector meson, providing additional robustness to our results. For the D*-meson, where some rates are experimentally known, agreement is found. The couplings are of additional interest as they govern the lowest pole residue in the B(D) → γ form factors which in turn are connected to QED-corrections in leptonic decays B(D) → ℓ$$ \overline{\nu} $$ ν ¯ . Since the couplings and residues are related by the decay constants $$ {f}_{H^{\ast}\left({H}_1\right)} $$ f H ∗ H 1 and $$ {f}_{H^{\ast}\left({H}_1\right)}^T $$ f H ∗ H 1 T , we determine them at next-leading order as a by-product. The quantities $$ \left\{{f}_{H^{\ast}}^T,{f}_{H_1}^T\right\} $$ f H ∗ T f H 1 T have not previously been subjected to a QCD sum rule determination. All results are compared with the existing experimental and theoretical literature.

scholarly journals The $$ \overline{B} $$ → π form factors from QCD and their impact on |Vub|

2021 ◽  
Vol 2021 (7) ◽  
Author(s):  
Domagoj Leljak ◽  
Blaženka Melić ◽  
Danny van Dyk
Keyword(s):  
Form Factor ◽  
Lattice Qcd ◽  
Sum Rules ◽  
Semileptonic Decay ◽  
Form Factors ◽  
Scalar Form Factor ◽  
Small Momentum Transfer ◽  
Scalar Form ◽  
Sum Rule ◽  
First Time

Abstract We revisit light-cone sum rules with pion distribution amplitudes to determine the full set of local $$ \overline{B} $$ B ¯ → π form factors. To this end, we determine all duality threshold parameters from a Bayesian fit for the first time. Our results, obtained at small momentum transfer q2, are extrapolated to large q2 where they agree with precise lattice QCD results. We find that a modification to the commonly used BCL parametrization is crucial to interpolate the scalar form factor between the two q2 regions. We provide numerical results for the form factor parameters — including their covariance — based on simultaneous fit of all three form factors to both the sum rule and lattice QCD results. Our predictions for the form factors agree well with measurements of the q2 spectrum of the semileptonic decay $$ {\overline{B}}^0\to {\pi}^{+}{\mathrm{\ell}}^{-}{\overline{\nu}}_{\mathrm{\ell}} $$ B ¯ 0 → π + ℓ − ν ¯ ℓ . From the world average of the latter we obtain |Vub| = (3.77 ± 0.15) · 10−3, which is in agreement with the most recent inclusive determination at the 1 σ level.

scholarly journals QCD parameter correlations from heavy quarkonia

2018 ◽  
Vol 33 (10) ◽  
pp. 1850045 ◽  
Author(s):  
Stephan Narison
Keyword(s):  
Sum Rules ◽  
Axial Vector ◽  
Gluon Condensate ◽  
Sum Rule ◽  
Channel One ◽  
Vector Channel ◽  
Stability Point ◽  
Pseudo Scalar ◽  
First Time ◽  
Good Agreement

Correlations between the QCD coupling [Formula: see text], the gluon condensate [Formula: see text] and the [Formula: see text], [Formula: see text]-quark running masses [Formula: see text] in the [Formula: see text]-scheme are explicitly studied (for the first time) from the (axial-)vector and (pseudo)scalar charmonium and bottomium ratios of Laplace sum rules (LSR) evaluated at the [Formula: see text]-subtraction stability point where perturbative (PT) @N2LO, N3LO and [Formula: see text] @NLO corrections are included. Our results clarify the (apparent) discrepancies between different estimates of [Formula: see text] from [Formula: see text] sum rule and also show the sensitivity of the sum rules on the choice of the [Formula: see text]-subtraction scale which does not permit a high-precision estimate of [Formula: see text]. We obtain from the (axial-)vector [respectively (pseudo)scalar] channels: [Formula: see text] [respectively [Formula: see text] GeV4, [Formula: see text] [respectively 1266(16)] MeV and [Formula: see text] MeV. Combined with our recent determinations from vector channel, one obtains the average: [Formula: see text] MeV and [Formula: see text] MeV. Adding the two above values of the gluon condensate to different previous estimates in Table 1, one obtains the 2018 sum rule average: [Formula: see text] GeV4. The mass-splittings [Formula: see text] give @N2LO: [Formula: see text] in good agreement with the world average.

Psychological Resilience Provides No Independent Protection From Suicidal Risk

Crisis ◽  
2016 ◽  
Vol 37 (2) ◽  
pp. 130-139 ◽  
Author(s):  
Danica W. Y. Liu ◽  
A. Kate Fairweather-Schmidt ◽  
Richard Burns ◽  
Rachel M. Roberts ◽  
Kaarin J. Anstey
Keyword(s):  
Risk Factors ◽  
Well Being ◽  
Current Status ◽  
Psychological Resilience ◽  
Cross Sectional ◽  
Life Project ◽  
Resilience Factors ◽  
First Time

Abstract. Background: Little is known about the role of resilience in the likelihood of suicidal ideation (SI) over time. Aims: We examined the association between resilience and SI in a young-adult cohort over 4 years. Our objectives were to determine whether resilience was associated with SI at follow-up or, conversely, whether SI was associated with lowered resilience at follow-up. Method: Participants were selected from the Personality and Total Health (PATH) Through Life Project from Canberra and Queanbeyan, Australia, aged 28–32 years at the first time point and 32–36 at the second. Multinomial, linear, and binary regression analyses explored the association between resilience and SI over two time points. Models were adjusted for suicidality risk factors. Results: While unadjusted analyses identified associations between resilience and SI, these effects were fully explained by the inclusion of other suicidality risk factors. Conclusion: Despite strong cross-sectional associations, resilience and SI appear to be unrelated in a longitudinal context, once risk/resilience factors are controlled for. As independent indicators of psychological well-being, suicidality and resilience are essential if current status is to be captured. However, the addition of other factors (e.g., support, mastery) makes this association tenuous. Consequently, resilience per se may not be protective of SI.

Synergetic Theory of Document in Evolution of Document Science

2018 ◽  
pp. 1060-1068
Author(s):  
Galina A. Dvoenosova ◽  
Keyword(s):  
Social Role ◽  
Scientific Study ◽  
Self Organization ◽  
Universal Theory ◽  
Social Self ◽  
Social Goal ◽  
The Social ◽  
Synergetic Theory ◽  
First Time

The article assesses synergetic theory of document as a new development in document science. In information society the social role of document grows, as information involves all members of society in the process of documentation. The transformation of document under the influence of modern information technologies increases its interest to representatives of different sciences. Interdisciplinary nature of document as an object of research leads to an ambiguous interpretation of its nature and social role. The article expresses and contends the author's views on this issue. In her opinion, social role of document is incidental to its being a main social tool regulating the life of civilized society. Thus, the study aims to create a scientific theory of document, explaining its nature and social role as a tool of social (goal-oriented) action and social self-organization. Substantiation of this idea is based on application of synergetics (i.e., universal theory of self-organization) to scientific study of document. In the synergetic paradigm, social and historical development is seen as the change of phases of chaos and order, and document is considered a main tool that regulates social relations. Unlike other theories of document, synergetic theory studies document not as a carrier and means of information transfer, but as a unique social phenomenon and universal social tool. For the first time, the study of document steps out of traditional frameworks of office, archive, and library. The document is placed on the scales with society as a global social system with its functional subsystems of politics, economy, culture, and personality. For the first time, the methods of social sciences and modern sociological theories are applied to scientific study of document. This methodology provided a basis for theoretical vindication of nature and social role of document as a tool of social (goal-oriented) action and social self-organization. The study frames a synergetic theory of document with methodological foundations and basic concepts, synergetic model of document, laws of development and effectiveness of document in the social continuum. At the present stage of development of science, it can be considered the highest form of theoretical knowledge of document and its scientific explanatory theory.

Physical Warmth Attenuates Ethnocentric Bias under Mortality Salience: An Embodied Terror Management Perspective

2020 ◽  
Author(s):  
Armand Chatard ◽  
Margaux Renoux ◽  
Jean Monéger ◽  
Leila Selimbegovic
Keyword(s):  
Mortality Salience ◽  
Terror Management ◽  
Negative Consequences ◽  
Defensive Reaction ◽  
Worldview Defense ◽  
Management Perspective ◽  
Physical Warmth ◽  
Alternative Means ◽  
First Time

Research indicates that individuals often deal with mortality salience by affirming beliefs in national or cultural superiority (worldview defense). Because worldview defense may be associated with negative consequences (discrimination), it is important to identify alternative means to deal with death-related thoughts. In line with an embodied terror management perspective, we evaluate for the first time the role of physical warmth in reducing defensive reaction to mortality salience. We predicted that, like social affiliation (social warmth), physical warmth could reduce worldview defense when mortality is salient. In this exploratory (preregistered) study, 202 French participants were primed with death-related thoughts, or an aversive control topic, in a heated room or a non-heated room. The main outcome was worldview defense (ethnocentric bias). We found no main effect of mortality salience on worldview defense. However, physical warmth reduced worldview defense when mortality was salient. Implications for an embodied terror management perspective are discussed.

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