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Gedanken Worlds without Higgs: QCD-Induced Electroweak Symmetry Breaking

Description: To illuminate how electroweak symmetry breaking shapes the physical world, we investigate toy models in which no Higgs fields or other constructs are introduced to induce spontaneous symmetry breaking. Two models incorporate the standard SU(3){sub c} {circle_times} SU(2){sub L} {circle_times} U(1){sub Y} gauge symmetry and fermion content similar to that of the standard model. The first class--like the standard electroweak theory--contains no bare mass terms, so the spontaneous breaking of chir… more
Date: January 1, 2009
Creator: Quigg, Chris & Shrock, Robert
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Maximal Wavelength of Confined Quarks and Gluons and Properties of Quantum Chromodynamics

Description: Because quarks and gluons are confined within hadrons, they have a maximum wavelength of order the confinement scale. Propagators, normally calculated for free quarks and gluons using Dyson-Schwinger equations, are modified by bound-state effects in close analogy to the calculation of the Lamb shift in atomic physics. Because of confinement, the effective quantum chromodynamic coupling stays finite in the infrared. The quark condensate which arises from spontaneous chiral symmetry breaking in t… more
Date: August 1, 2008
Creator: Brodsky, Stanley J. & Shrock, Robert
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Condensates in Quantum Chromodynamics and the Cosmological Constant

Description: Casher and Susskind have noted that in the light-front description, spontaneous chiral symmetry breaking in quantum chromodynamics (QCD) is a property of hadronic wavefunctions and not of the vacuum. Here we show from several physical perspectives that, because of color confinement, quark and gluon QCD condensates are associated with the internal dynamics of hadrons. We discuss condensates using condensed matter analogues, the AdS/CFT correspondence, and the Bethe-Salpeter/Dyson-Schwinger appro… more
Date: May 8, 2009
Creator: Brodsky, Stanley J. & Shrock, Robert
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Light-Front Holography and Hadronization at the Amplitude Level

Description: The correspondence between theories in anti-de Sitter space and conformal field theories in physical space-time leads to an analytic, semiclassical model for strongly-coupled QCD which has scale invariance at short distances and color confinement at large distances. Light-front holography is a remarkable feature of AdS/CFT: it allows hadronic amplitudes in the AdS fifth dimension to be mapped to frame-independent light-front wavefunctions of hadrons in physical space-time, thus providing a rela… more
Date: July 25, 2008
Creator: Brodsky, Stanley J.; de Teramond, Guy & Shrock, Robert
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Confinement Contains Condensates

Description: Dynamical chiral symmetry breaking and its connection to the generation of hadron masses has historically been viewed as a vacuum phenomenon. We argue that confinement makes such a position untenable. If quark-hadron duality is a reality in QCD, then condensates, those quantities that have commonly been viewed as constant empirical mass-scales that fill all spacetime, are instead wholly contained within hadrons; i.e., they are a property of hadrons themselves and expressed, e.g., in their Bethe… more
Date: March 12, 2012
Creator: Brodsky, Stanley J.; Roberts, Craig D.; Shrock, Robert & Tandy, Peter C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spatial Dependence of Condensates in Strongly Coupled Gauge Theories

Description: We analyze quark and gluon condensates in quantum chromodynamics. We suggest that these are localized inside hadrons, because the particles whose interactions are responsible for them are confined within these hadrons. This can explain the results of recent studies of gluon condensate contributions to vacuum correlators. We also give a general discussion of condensates in asymptotically free vectorial and chiral gauge theories.
Date: March 25, 2008
Creator: Brodsky, Stanley J.; /SLAC /SUNY, Stony Brook; Shrock, Robert & /SUNY, Stony Brook
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Essence of the Vacuum Quark Condensate

Description: We show that the chiral-limit vacuum quark condensate is qualitatively equivalent to the pseudoscalar meson leptonic decay constant in the sense that they are both obtained as the chiral-limit value of well-defined gauge-invariant hadron-to-vacuum transition amplitudes that possess a spectral representation in terms of the current-quark mass. Thus, whereas it might sometimes be convenient to imagine otherwise, neither is essentially a constant mass-scale that fills all spacetime. This means, in… more
Date: August 25, 2010
Creator: Brodsky, Stanley J.; /SLAC /Southern Denmark U., CP3-Origins; Roberts, Craig D.; /Argonne, PHY /Peking U.; Shrock, Robert; /YITP, Stony Brook et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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