2019/04/19 by Jared Kaplan, Sandipan Kundu · 1 citation
Physics and Astronomy · #Black Holes and Theoretical Physics #Bound state #Cosmology and Gravitation Theories #Eikonal approximation #Gauge (firearms) #Gauge theory #Gravitation #Planck scale #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Spacetime #Spin (aerodynamics) #gr-qc #hep-ph #hep-th
paper · pdf · doi:10.1007/jhep11(2019)142
44 pages + appendices, multiple figures
arxiv created 2019/04/19 · openalex created_date 2019/04/25 · openalex publication_date 2019/11/01 · arxiv updated 2020/01/29 · openalex updated_date 2026/08/05
A bstract Causality constrains the gravitational interactions of massive higher spin particles in both AdS and flat spacetime. We explore the extent to which these constraints apply to composite particles, explaining why they do not rule out macroscopic objects or hydrogen atoms. However, we find that they do apply to glueballs and mesons in confining large N gauge theories. Assuming such theories contain massive bound states of general spin, we find parametric bounds in (3 + 1) spacetime dimensions of the form N\lesssim \fracMPlΛQCD <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>N</mml:mi> <mml:mo>≲</mml:mo> <mml:mfrac> <mml:msub> <mml:mi>M</mml:mi> <mml:mi>Pl</mml:mi> </mml:msub> <mml:msub> <mml:mi>Λ</mml:mi> <mml:mi>QCD</mml:mi> </mml:msub> </mml:mfrac> </mml:math> relating N, the QCD scale, and the Planck scale. We also argue that a stronger bound replacing ∧ QCD with the UV cut-off scale may be derived from eikonal scattering in flat spacetime.