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This study delves into the analysis of QCD correlators, exploring their physical content and relation to RcT sum rules. Examining truncated RcT with pQCD continuum, it discusses local duality challenges and resonance theory implications in QCD at large NC. The convergence of high mass resonances and continuum behaviors are highlighted, emphasizing the dominance of pQCD in analytical frameworks and the phenomenological relevance of specific correlators.
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Recovering QCD at large NC:Two-point Green-functions J. J. Sanz Cillero, IN2P3 - Orsay
DUALITY QCD at large NC (QCD∞) Resonance Theory (RcT∞) Outline: • Analysis of QCD correlators: • a)- Physical QCD content • b)- Relation RcT Sum-rules • c)- Truncated RcT + “pQCD Continuum” • Conclusions
QCD∞ Infinite resonance Regularization CUT-OFF Regularization …… RcT∞ RcT(n)
pQCD pQCD LOCAL DUALITY RcT∞QCD∞ … Local Duality NOT POSSIBLE at LO in 1/NC !
UV divergent • Scale dependent • Logarithmic behaviour • Physical & finite • m independent • Logs within as Left-left correlator inQCD∞ & AA correlator & VV correlator • Short distance behaviour inpQCDfor (V+A): [ Shiftman et al. ’76 ]
UV DIVERGENT when M∞2∞ UV finite when M∞2∞ • Resonance description: Resonance Effective Theory with q2= -Q2 < 0 RcT at Large NC
[ Peris et al. ´98 ] [ Beane ’ 01 ] [ Golterman & Peris ‘ 01 ] … • Integral representation of discrete series: From series to integral with the function and the interspacing
Short distance QCD : Information about higher multiplets pQCD Relation with sum-rules: QCDdispersion relations Infinite series fromRcT
High mass resonances: Origin of the “Continuum” Convergence of H(t) around Truncated RcT “CONTINUUM” “pQCD Continuum” s Mc2
High and low energy Hierarchies Analytical pQCD: DOMINANT Non-analytical cPT: Analytical DOMINANT
Phenomenology: V+A Adler-function NO “CONTINUUM” (without pion pole) Truncated RcT + “CONTINUUM” (without pion pole)
Duality: QCDRcT (local & global) QCDat large NC : Infinite resonance summation Hierarchy Truncated RcT + pQCD continuum Logarithmic & UV behaviour Short distances: Continuum dominance Long distances: Lightest resonances Phenomenological success
OUTLOOK: • Form-factors (Correlators at NLO in 1/NC) • Other non-order-parameter Green-funtions • Scattering amplitudes ? ? ?
In general: Example for the scalar correlator • In addition: LOCAL DUALITY AVERAGED (GLOBAL) DUALITY
Phenomenology: Vector Adler-function NO CONTINUUM (without pion pole) Truncated RcT + CONTINUUM (without pion pole)