The basic concepts of some frontier fundamental physical theories are hard to test with Earth-based experiments. For example, string theory utilizes extra dimensions of possibly very small scale in an effort to construct a theory of quantum gravity, but accelerator experiments are currently probing energies which could be orders of magnitude lower than those necessary to test these ideas. On the other hand, the universe has already set up diverse experiments under conditions we cannot hope to duplicate on Earth. Are there ways to test the frontier concepts of physics through astrophysical observations? In this talk I will discuss using observations of radio transients as a probe of quantum gravity ideas. The specific case of the explosion of a primordial black hole will form the basis of the discussion.

Over the last decade, extragalactic surveys at ultraviolet to far-infrared wavelengths have shown that the bulk of galaxy assembly occurred at z>0.5, with a significant fraction of this assembly taking place in obscured `bursts' of intense activity. In this talk I will focus on how, when and why star formation and accretion onto central supermassive black holes takes place. I will also discuss the physics of starbursts and AGN with particular reference to the idea of `AGN feedback'. AGN feedback is a process by which the central supermassive black hole acts to terminate star formation in the host galaxy and/or further accretion onto the black hole itself. Galaxy evolution models that incorporate AGN feedback are more successful in reproducing observations, but direct evidence for AGN feedback is still sparse. In this talk, I will present results from two ongoing projects that are providing strong evidence for AGN feedback.

Measuring fundamental physical parameters of Active Galactic Nuclei (AGNs) is paramount to understanding the mechanisms underlying the highly energetic phenomenon of accretion onto supermassive black holes (BH), the feeding and feedback of the host galaxy, and their co-evolution. Very few methods provide reliable and independent mass estimates. One such method is spectroscopic reverberation mapping (RM) and has been applied so far to about 40 AGNs in the highest mass regimes (i.e., > 10^6 solar masses). Our group has been attempting to measure the low mass end (< 10^6 solar masses) where observations are difficult due to short time delays (i.e., hours to days). I will discuss the difficulties, methods and results from our spectroscopic RM campaigns as well as a new photometric RM method that could potentially be used in large time series surveys (like the upcoming LSST) to estimate the masses of a large number of AGNs. Combining these masses with other parameters of the host galaxies we hope to better understand the role of AGNs in galaxy formation and evolution.

Large-scale outflows of gas from galaxies ("galactic winds") have a profound impact on their hosts. They act as negative feedback on both star formation and the activity of supermassive black holes. Though much is known about winds in nearby spiral galaxies, the nature of winds in galaxy mergers remains more uncertain. I will discuss new observations of galactic winds in galaxy mergers that reveal in detail the physical structure of multiple gas phases and probe the power sources of these winds. In several cases, a QSO is implicated in powering the wind. These new observations harness integral field spectrographs on the largest optical telescopes.

The talk will be in 2 parts, summarizing the 2 projects I have been working on over the last year. Ultra-strong FeII emission in Large Quasar Groups: We have found a potential excess of quasars with strong and ultra-strong UV FeII emission, residing within a series of large quasars groups, presenting the first suggestion a unique environment within these groups.

Quantifying the nature of intra-cluster light in a Fornax-like cluster: Using N-body simulations we are studying the nature of intra-cluster light by considering the differences in the distributions of disk and halo stars, and the contribution of the cD galaxy to the amount of intra-cluster light. We found that using a single observation estimator is likely to underestimate the lot amount of intra-cluster light in a Fornax-like cluster.

Sub-relativistic outflows are seen as blueshifted absorption troughs in the spectra of roughly one third of all quasars. I will describe a recent breakthrough, enabled by HST/COS and VLT/Xshooter observations, that yield the mass flux and kinetic luminosity for the majority of these outflows. The derived values suggest that quasar absorption outflows have a profound effect on the host galaxy.

Twenty years ago we knew of nine planets and based our entire understanding of planetary physics on the Solar System. We now have confirmed detections of over 700 extrasolar planets, with another 2600 likely candidates. Most of these exoplanets are completely unlike any planet orbiting our Sun and have inspired theorists to expand our understanding of planetary physics into new and interesting regimes. One truly exciting observational development has been the ability to directly measure atmospheric characteristics (composition, temperature, spatial information) for some of these planets. I will describe the current state of knowledge in the study of exo-atmospheres, the challenges in modeling exotic atmospheres and interpreting noisy measurements, and discuss the future direction of this field. I will focus on the class of exoplanets known as "hot Jupiters", planets with masses comparable to Jupiter and that orbit ten times closer to their host star than Mercury is from our Sun. These planets are the most easily detected and amenable to atmospheric characterization, but the techniques that we use to study hot Jupiters can be applied to lower mass planets, in line with the distant goal of characterizing an exo-Earth.

The formation of rotationally supported disks (RSDs) is a crucial event of the early times of star formation.

There are theoretical difficulties in forming rotationally supported disks during the protostellar collapse of magnetized dense cores. It is often expected that disks would form automatically out of the collapse of rotating cores because of angular momentum conservation. In the presence of the observed level of magnetic fields, this simple explanation is no longer guaranteed to work, because of magnetic braking and magnetic instabilities. Indeed, in the simplest case of the ideal MHD limit, both analytic work and numerical simulations showed that RSD formation is completely suppressed by excessive magnetic braking.

Our axisymetric simulations have shown recently that non-ideal MHD effects (including Ohmic dissipation, ambipolar diffusion and the Hall effect) do not weaken the magnetic braking enough to enable RSDs to form under typical cloud conditions.

Nevertheless, RSDs are observed around at least more evolved young stellar objects and have to form sooner or later. I will discuss possible resolutions to this problem, including non-axisymmetric magnetic interchange instabilities in 3D, misalignment of magnetic field and rotation, enhanced magnetic diffusivities (perhaps due to turbulence or reconnection), and outflow stripping of the protostellar envelope, and comment on the apparently discrepant results in the literature on this important topic of the early epoch of star formation.

I will give an introduction about ultra-fast outflows and their potential significance as feedback mechanism on galaxy evolution, one of the major outstanding issues in astronomy. Afterwards I will present a detailed statistical analyses of a large sample of these outflows obtained by Tombesi. I will show that the sample properties are indistinguishable from those of noise. I will briefly go over a second survey by Gofford et al. before discussing some of the individual sources for which UFOs have been claimed. Finally, as a point of discussion I will give some statistics on the UFO literature.