50 research outputs found
Being, Becoming and the Undivided Universe: A Dialogue between Relational Blockworld and the Implicate Order Concerning the Unification of Relativity and Quantum Theory
In this paper two different approaches to unification will be compared,
Relational Blockworld (RBW) and Hiley's implicate order. Both approaches are
monistic in that they attempt to derive matter and spacetime geometry 'at once'
in an interdependent and background independent fashion from something
underneath both quantum theory and relativity. Hiley's monism resides in the
implicate order via Clifford algebras and is based on process as fundamental
while RBW's monism resides in spacetimematter via path integrals over graphs
whereby space, time and matter are co-constructed per a global constraint
equation. RBW's monism therefore resides in being (relational blockworld) while
that of Hiley's resides in becoming (elementary processes). Regarding the
derivation of quantum theory and relativity, the promises and pitfalls of both
approaches will be elaborated. Finally, special attention will be paid as to
how Hiley's process account might avoid the blockworld implications of
relativity and the frozen time problem of canonical quantum gravity.Comment: 33 pages, 7 figures. Revised to include modified Regge calculus
results. Accepted for publication in Foundations of Physics. arXiv admin
note: substantial text overlap with arXiv:1106.333
Heavy quarkonium: progress, puzzles, and opportunities
A golden age for heavy quarkonium physics dawned a decade ago, initiated by
the confluence of exciting advances in quantum chromodynamics (QCD) and an
explosion of related experimental activity. The early years of this period were
chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in
2004, which presented a comprehensive review of the status of the field at that
time and provided specific recommendations for further progress. However, the
broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles
could only be partially anticipated. Since the release of the YR, the BESII
program concluded only to give birth to BESIII; the -factories and CLEO-c
flourished; quarkonium production and polarization measurements at HERA and the
Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the
deconfinement regime. All these experiments leave legacies of quality,
precision, and unsolved mysteries for quarkonium physics, and therefore beg for
continuing investigations. The plethora of newly-found quarkonium-like states
unleashed a flood of theoretical investigations into new forms of matter such
as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the
spectroscopy, decays, production, and in-medium behavior of c\bar{c}, b\bar{b},
and b\bar{c} bound states have been shown to validate some theoretical
approaches to QCD and highlight lack of quantitative success for others. The
intriguing details of quarkonium suppression in heavy-ion collisions that have
emerged from RHIC have elevated the importance of separating hot- and
cold-nuclear-matter effects in quark-gluon plasma studies. This review
systematically addresses all these matters and concludes by prioritizing
directions for ongoing and future efforts.Comment: 182 pages, 112 figures. Editors: N. Brambilla, S. Eidelman, B. K.
Heltsley, R. Vogt. Section Coordinators: G. T. Bodwin, E. Eichten, A. D.
Frawley, A. B. Meyer, R. E. Mitchell, V. Papadimitriou, P. Petreczky, A. A.
Petrov, P. Robbe, A. Vair