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We examine the origin and evolution of correlations between properties of supermassive BHs and their host galaxies using simulations of major galaxy mergers, including the effects of gas dissipation, cooling, star formation, and BH accretion and feedback. We demonstrate that the simulations predict the existence of a BH "fundamental plane" (BHFP), of the form MBH [?] s3.0+-0.3Rimg1.gif or MBH [?] Mimg2.gifs2.2+-0.5, similar to relations found observationally. The simulations indicate that the BHFP can be understood roughly as a tilted intrinsic correlation between BH mass and spheroid binding energy, or the condition for feedback coupling to power a pressure-driven outflow. While changes in halo circular velocity, merger orbital parameters, progenitor disk redshifts and gas fractions, ISM gas pressurization, and other parameters can drive changes in, e.g., s at fixed M*, and therefore changes in the MBH-s or MBH-M* relations, the BHFP is robust. Given the empirical trend of decreasing Re for a given M* at high redshift (i.e., increasingly deep potential wells), the BHFP predicts that BHs will be more massive at fixed M*, in good agreement with recent observations. This evolution in the structural properties of merger remnants, to smaller Re and larger s (and therefore larger MBH, conserving the BHFP) at a given M*, is driven by the fact that disks (merger progenitors) have characteristically larger gas fractions at high redshifts. Adopting the observed evolution of disk gas fractions with redshift, our simulations predict the observed trends in both Re(M*) and MBH(M*). The existence of this BHFP also has important implications for the masses of the very largest black holes and immediately resolves several apparent conflicts between the BH masses expected and measured for outliers in both the MBH-s and MBH-M* relations.

We study observed correlations between supermassive black hole (BHs) and the properties of their host galaxies and show that the observations define a BH "fundamental plane" (BHFP), of the form MBH [?] s3.0+-0.3Rimg1.gif or MBH [?] Mimg2.gifs2.2+-0.5, analogous to the FP of elliptical galaxies. The BHFP is preferred over a simple relation between MBH and any of s, M*, Mdyn, or Re alone at >3 s (99.9%) significance. The existence of this BHFP has important implications for the formation of supermassive BHs and the masses of the very largest black holes and immediately resolves several apparent conflicts between the BH masses expected and measured for outliers in both the MBH-s and MBH-M* relations.

We describe a model-independent integral constraint that defines an upper limit to the allowed degree of evolution in the ratio of black hole (BH) mass to host galaxy luminosity or mass, as a function of redshift. Essentially, if the BH/host ratio is excessive at redshift z, then it would imply that the total mass density in BHs above some Mimg1.gif is larger at that redshift than at z = 0, which is impossible. This argument requires no knowledge of host or BH properties, only a lower limit to the observed luminosity density in the brightest galaxies at some z. We calculate this upper limit from a variety of luminosity and mass functions in different bands from redshifts z = 0-2. We show that it is consistent with passive evolution of spheroid populations (with a fixed MBH/Mhost relation) in all cases, and provides tighter constraints than have generally been obtained previously, ruling out at [?]6 s observational and theoretical estimates suggesting that MBH/Mhost was significantly larger at high redshifts than locally. We discuss a variety of possible "loopholes" or changes in the BH/host populations and correlations, and show that they typically lower the upper limits and strengthen our conclusions.

The next-generation weak lensing surveys (i.e., LSST, Euclid, and WFIRST) will require exquisite control over systematic effects. In this paper, we address shear calibration and present the most realistic forecast to date for LSST/Euclid/WFIRST and CMB lensing from a stage 4 CMB experiment ("CMB S4"). We use the cosmolike code to simulate a joint analysis of all the two-point functions of galaxy density, galaxy shear, and CMB lensing convergence. We include the full Gaussian and non-Gaussian covariances and explore the resulting joint likelihood with Monte Carlo Markov chains. We constrain shear calibration biases while simultaneously varying cosmological parameters, galaxy biases, and photometric redshift uncertainties. We find that CMB lensing from CMB S4 enables the calibration of the shear biases down to 0.2%-3% in ten tomographic bins for LSST (below the ~0.5% requirements in most tomographic bins), down to 0.4%-2.4% in ten bins for Euclid, and 0.6%-3.2% in ten bins for WFIRST. For a given lensing survey, the method works best at high redshift where shear calibration is otherwise most challenging. This self-calibration is robust to Gaussian photometric redshift uncertainties and to a reasonable level of intrinsic alignment. It is also robust to changes in the beam and the effectiveness of the component separation of the CMB experiment, and slowly dependent on its depth, making it possible with third-generation CMB experiments such as AdvACT and SPT-3G, as well as the Simons Observatory. [ABSTRACT FROM AUTHOR]

We reexamine interactions between the dark sectors of cosmology, with a focus on robust constraints that can be obtained using only mildly nonlinear scales. While it is well known that couplings between dark matter and dark energy can be constrained to the percent level when including the full range of scales probed by future optical surveys, calibrating matter power spectrum emulators to all possible choices of potentials and couplings requires many computationally expensive n-body simulations. Here we show that lensing and clustering of galaxies in combination with the cosmic microwave background (CMB) are capable of probing the dark sector coupling to the few percent level for a given class of models, using only linear and quasilinear Fourier modes. These scales can, in principle, be described by semianalytical techniques such as the effective field theory of large-scale structure. [ABSTRACT FROM AUTHOR]

One of the most pernicious theoretical systematics facing upcoming gravitational lerising surveys is the uncertainty introduced by the effects of baryons on the power spectrum of the convergence field. One method that has been proposed to account for these effects is to allow several additional parameters (that characterize dark matter halos) to vary and to fit lensing data to these halo parameters concurrently with the standard set of cosmological parameters. We test this method. In particular, we use this technique to model convergence power spectrum predictions from a set of cosmological simulations. We estimate biases in dark energy equation-of-state parameters that would be incurred if one were to fit the spectra predicted by the simulations either with no model for baryons or with the proposed method. We show that neglecting baryonic effect leads to biases in dark energy parameters that are several times the statistical errors for a survey like the Dark Energy Survey. The proposed method to correct for baryonic effects renders the residual biases in dark energy equation-of-state parameters smaller than the statistical errors. These results suggest that this mitigation method may be applied to analyze convergence spectra from a survey like the Dark Energy Survey. For significantly larger surveys, such as will be carried out by the Large Synoptic Survey Telescope, the biases introduced by baryonic effects are much more significant. We show that this mitigation technique significantly reduces the biases for such larger surveys, but that a more effective mitigation strategy will need to be developed in order ensure that the residual biases in these surveys fall below the statistical errors. [ABSTRACT FROM AUTHOR]