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Conformal Gravity in the X-ray Cluster Abell 2029. galaxies. Keith Horne SUPA St Andrews. monster galaxy. 10 8 K gas. Mannheim-Kazanas metric. Source-free field equations:. Static, spherical symmetry:. Analogous results including rotation and charge. Solar System Dynamics.
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Conformal Gravity in the X-ray Cluster Abell 2029 galaxies Keith Horne SUPA St Andrews monster galaxy 108K gas
Mannheim-Kazanas metric Source-free field equations: Static, spherical symmetry: Analogous results including rotation and charge.
Solar System Dynamics Schwarzschild metric: Fixes one parameter
Galaxy Rotation Curves Linear potential gives a distance-independent inward acceleration.
Mannheim 1993, 1997. ( fits two more parameters) Galaxy Rotation Curves Universal inward acceleration.
Newton Mannheim Exterior mass matters ! No net force from external shells Hook’s law force toward centre of external shell
linear potential stars gas Fits adjust [M/L]* All mass in edge-on disk plane. Rotation Curve Fits NGC 1560 poorest fit. Data wiggles follow the gas.
200 Kpc Probes gravity on 10x larger scales Abell 2029 Chandra X-ray Image of Abell 2029 The galaxy cluster Abell 2029 is composed of thousands of galaxies enveloped in a gigantic cloud of hot gas, and an amount of dark matter equivalent to more than a hundred trillion Suns. At the center of this cluster is an enormous, elliptically shaped galaxy that is thought to have been formed from the mergers of many smaller galaxies.
X-ray Gas Spherical symmetry + Hydrostatic Equilibrium: Gravity and Total Mass profile:
Lewis, Stocke, Buote 2002. X-ray Gas 3-300 kpc r(r) T(r) cs(r) sgals P(r) v* sin(i)
g(r) g(r) gas stars gas stars M(<r) M(<r) gas gas stars stars Gravity and Total Mass profiles: Newtonian Analysis 90% Dark Matter Required !
g(r) g(r) gas stars gas stars M(<r) M(<r) gas gas stars stars Gravity and Total Mass profiles: Conformal Gravity Dark Matter NOT required ! Too Much Conformal Gravity!
g(r) g(r) gas stars gas stars M(<r) M(<r) gas gas stars stars Newton vs Conformal Gravity
Discussion Points : )Dark Matter is not needed to bind the X-ray Gas. : (Too much Conformal Gravity ! • Conformal Gravity ruled out? (Not yet.) External material -- external Void ? Mannheim-Kazanas metric incomplete? Not in Higgs gauge --> vacuum polarisation. • Quadratic potential terms important? External shells of distant galaxies should generate a universal quadratic potential. • Gas not in hydrostatic equilibrium? Rotation/infall/outflow V > 1000 km/s? Doppler shift detectable in future X-ray spectroscopy. • Stars generate the gravity -- not the hot gas? Same problem as in the colliding clusters 1E0657-56 ?
Conformal Symmetry Clock ticks and rulers stretch by a factor that can vary in time and space. Invariants: angles, velocities, light cones, causality. Weyl action:
Higgs mass: Fermion mass: Conformal Matter Action Equations of motion:
Higgs potential: Higgs mass: Fermion mass: Dynamical Mass Generation Symmetry Breaking Higgs potential: Ricci scalar: (negative spatial curvature). (negative vacuum energy)
Higgs Guage Fermion mass: = matter + geometry + vacuum matter fields => perfect fluid
Fermion mass: Mannheim 1993. Conformal trajectories Test particle action. Trajectory for which action is stationary. Conformal trajectories are the geodessic trajectories in the Higgs gauge.
Trace Condition Ricci scalar in the vacuum 0 = matter + geometry + vacuum
Ricci scalar: MK metric -> Higgs guage Mannheim-Kazanas metric is not in Higgs guage. Test particles will not follow MK geodessics.