How Black Holes Stop Their Host Galaxy from Growing Without AGN Feedback
  Super-massive black holes (SMBHs) with $M_{\bullet} \sim 10^9 $ M$_{\odot}$
at $z>6$ likely originate from massive seed black holes (BHs). We investigate
the consequences of seeding SMBHs with direct collapse BHs (DCBHs)
($M_{\bullet}=10^{4-6}\, \mathrm{M}_\odot$) on proto-galactic disc growth. We
show that even in the absence of direct feedback effects, the growth of seed
BHs reduces the development of gravitational instabilities in host galaxy
discs, suppressing star formation and confining stars to a narrow ring in the
disc and leading to galaxies at $z \sim 6$ which lie above the local BH-stellar
mass relation. The relative magnitude of cosmic and BH accretion rates governs
the evolution of the BH-stellar mass relation. For typical DCBH formation
epochs, $z_{\rm{i}} \sim 10$, we find star formation is inhibited in haloes
growing at the average rate predicted by $\Lambda$CDM which host BHs capable of
reaching $M_{\bullet}\sim 10^9 \, \mathrm{M}_{\odot}$ by $z\gtrsim6$. Slower
growing BHs cause a delay in the onset of star formation; a $M_{\bullet} \sim
10^6 $ M$_{\odot}$ seed growing at $0.25$ times the Eddington limit will delay
star formation by $\sim100$ Myr. This delay is reduced by a factor of $\sim10$
if the halo growth rate is increased by $\sim 0.6\, \sigma$. Our results
suggest that SMBHs seeded by DCBHs and their host galaxies form in separate
progenitor haloes. In the absence of subsequent mergers, higher than average
cosmic accretion or earlier seed formation ($z_{\rm i} \sim 20$) are required
to place the evolving BH on the local BH-stellar mass relation by $z=6$.
