Publications (146)
The Column Density Distribution of the Lyman-Alpha Forest: A Measure of Small Scale Power
Lam Hui, Nickolay Y. Gnedin, Yu Zhang
Absorption lines in the Lyman-alpha forest can be thought of as peaks in neutral hydrogen density along lines of sight. The column density distribution (the number density of absor…
Two-dimensional Lorentz invariance of spherically symmetric black holes
Lam Hui, Alberto Nicolis
We show that a static spherically symmetric black hole, in a generic theory of gravity with generic matter fields, has a two-dimensional Lorentz symmetry.
No-Go Theorems for Generalized Chameleon Field Theories
Junpu Wang, Lam Hui, Justin Khoury
The chameleon, or generalizations thereof, is a light scalar that couple to matter with gravitational strength, but whose manifestation depends on the ambient matter density. A key…
Cosmology Constraints from the Weak Lensing Peak Counts and the Power Spectrum in CFHTLenS
Jia Liu, Andrea Petri, Zoltan Haiman +3
Lensing peaks have been proposed as a useful statistic, containing cosmological information from non-Gaussianities that is inaccessible from traditional two-point statistics such a…
Black hole superradiance with (dark) matter accretion
Lam Hui, Y. T. Albert Law, Luca Santoni +3
Studies of black hole superradiance often focus on the growth of a cloud in isolation, accompanied by the spin-down of the black hole. In this paper, we consider the additional eff…
Clustering of Luminous Red Galaxies IV: Baryon Acoustic Peak in the Line-of-Sight Direction and a Direct Measurement of H(z)
Enrique Gaztanaga, Anna Cabre, Lam Hui
We study the clustering of LRG galaxies in the latest spectroscopic SDSS data releases, DR6 and DR7, which sample over 1 Gpc^3/h^3 to z=0.47. The 2-point correlation function $\xis…
A no-hair theorem for the galileon
Lam Hui, Alberto Nicolis
We consider a galileon field coupled to gravity. The standard no-hair theorems do not apply, because of the galileon's peculiar derivative interactions. We prove that, nonetheless,…
Equivalence Principle Implications of Modified Gravity Models
Lam Hui, Alberto Nicolis, Christopher Stubbs
Theories that attempt to explain the observed cosmic acceleration by modifying general relativity all introduce a new scalar degree of freedom that is active on large scales, but i…
Quasinormal modes, echoes and the causal structure of the Green's function
Lam Hui, Daniel Kabat, Sam S. C. Wong
Quasinormal modes describe the return to equilibrium of a perturbed system, in particular the ringdown phase of a black hole merger. But as globally-defined quantities, the quasino…
Anisotropic Magnification Distortion of the 3D Galaxy Correlation: I. Real Space
Lam Hui, Enrique Gaztanaga, Marilena LoVerde
It is well known gravitational lensing, mainly via magnification bias, modifies the observed galaxy/quasar clustering. Such discussions have largely focused on the 2D angular corre…
Generation and propagation of nonlinear quasi-normal modes of a Schwarzschild black hole
Macarena Lagos, Lam Hui
In the analysis of a binary black hole coalescence, it is necessary to include gravitational self-interactions in order to describe the transition of the gravitational wave signal…
CMB Power Asymmetry from Non-Gaussian Modulation
Fabian Schmidt, Lam Hui
Non-Gaussianity in the inflationary perturbations can couple observable scales to modes of much longer wavelength (even superhorizon), leaving as a signature a large-angle modulati…
Dynamics of Strongly Twisted Relativistic Magnetospheres
Kyle Parfrey, Andrei M. Beloborodov, Lam Hui
Magnetar magnetospheres are believed to be strongly twisted, due to shearing of the stellar crust by internal magnetic stresses. We present time-dependent axisymmetric simulations…
The Statistics of Density Peaks and the Column Density Distribution of the Lyman-Alpha Forest
Lam Hui, Nickolay Y. Gnedin, Yu Zhang
We develop a method to calculate the column density distribution of the Lyman-alpha forest for column densities in the range . The Zel'dovich approxi…
Asymmetric galaxy correlation functions
Camille Bonvin, Lam Hui, Enrique Gaztanaga
We study the two-point cross-correlation function between two populations of galaxies: for instance a bright population and a faint population. We show that this cross-correlation…
Binary Systems as Resonance Detectors for Gravitational Waves
Lam Hui, Sean T. McWilliams, I-Sheng Yang
Gravitational waves at suitable frequencies can resonantly interact with a binary system, inducing changes to its orbit. A stochastic gravitational-wave background causes the orbit…
Superheavy Dark Matter from Thermal Inflation
Lam Hui, Ewan D. Stewart
It is quite plausible that the mass of the dark matter particle increases significantly after its freeze-out, due to a scalar field rolling to large values. We describe a realizati…
An analytic approach to quasinormal modes for coupled linear systems
Lam Hui, Alessandro Podo, Luca Santoni +1
Quasinormal modes describe the ringdown of compact objects deformed by small perturbations. In generic theories of gravity that extend General Relativity, the linearized dynamics o…
How Many Galaxies Fit in a Halo? Constraints on Galaxy Formation Efficiency from Spatial Clustering
Roman Scoccimarro, Ravi K. Sheth, Lam Hui +1
We study galaxy clustering using halo models, where gravitational clustering is described in terms of dark matter halos. At small scales, clustering statistics are dominated by hal…
Lensing Corrections to Features in the Angular Two-Point Correlation Function and Power Spectrum
Marilena LoVerde, Lam Hui, Enrique Gaztanaga
It is well known that magnification bias, the modulation of galaxy or quasar source counts by gravitational lensing, can change the observed angular correlation function. We invest…
The Low Column Density Lyman-alpha Forest
Nickolay Y. Gnedin, Lam Hui
We develop an analytical method based on the lognormal approximation to compute the column density distribution of the Lyman-alpha forest in the low column density limit. We comput…
The effect of peculiar velocities on supernova cosmology
Tamara M Davis, Lam Hui, Joshua A Frieman +11
We present an analysis of peculiar velocities and their effect on supernova cosmology. In particular, we study (a) the corrections due to our own motion, (b) the effects of correla…
Squeezing out of the matter bispectrum with consistency relations
Samuel Goldstein, Angelo Esposito, Oliver H. E. Philcox +4
We show how consistency relations can be used to robustly extract the amplitude of local primordial non-Gaussianity () from the squeezed limit of the matter bispectrum,…
A Linear Perturbation Theory of Inhomogeneous Reionization
Jun Zhang, Lam Hui, Zoltan Haiman
We develop an analytic approach to study inhomogeneous reionization on large scales by solving the equations of ionization balance and radiative transfer to first order in perturba…
Beyond Lyman-alpha: Constraints and Consistency Tests from the Lyman-beta Forest
Mark Dijkstra, Adam Lidz, Lam Hui
Absorption between the rest-frame wavelengths of 973 and 1026 Angstroms in quasar spectra arises from two sources (apart from occasional metals): one is due to Lyman-alpha (Lya) ab…
Linear and nonlinear contributions to pairwise peculiar velocities
Ravi K. Sheth, Lam Hui, Antonaldo Diaferio +1
We write the correlation function of dark matter particles, xi(r), as the sum of two terms - one which accounts for nonlinear evolution, and dominates on small scales, and another…
Intrinsic/Extrinsic Density-Ellipticity Correlations and Galaxy-Galaxy Lensing
Lam Hui, Jun Zhang
We compute both extrinsic (lensing) and intrinsic contributions to the (galaxy-)density-ellipticity correlation function, the latter done using current analytic theories of tidal a…
Pseudo-redundant vacuum energy
Puneet Batra, Kurt Hinterbichler, Lam Hui +1
We discuss models that can account for today's dark energy. The underlying cosmological constant may be Planck scale but starts as a redundant coupling which can be eliminated by a…
An equivalence principle for scalar forces
Lam Hui, Alberto Nicolis
The equivalence of inertial and gravitational masses is a defining feature of general relativity. Here, we clarify the status of the equivalence principle for interactions mediated…
Stellar Structure and Tests of Modified Gravity
Philip Chang, Lam Hui
Theories that attempt to explain cosmic acceleration by modifying gravity typically introduces a long-range scalar force that needs to be screened on small scales. One common scree…
Large-scale Bias and Efficient Generation of Initial Conditions for Non-Local Primordial Non-Gaussianity
Roman Scoccimarro, Lam Hui, Marc Manera +1
We study the scale-dependence of halo bias in generic (non-local) primordial non-Gaussian (PNG) initial conditions of the type motivated by inflation, parametrized by an arbitrary…
Gravitational Lensing as Signal and Noise in Lyman-alpha Forest Measurements
Marilena LoVerde, Stefanos Marnerides, Lam Hui +2
In Lyman-alpha forest measurements it is generally assumed that quasars are mere background light sources which are uncorrelated with the forest. Gravitational lensing of the quasa…
Recovery of the Shape of the Mass Power Spectrum from the Lyman-alpha Forest
Lam Hui
We propose a method for recovering the shape of the mass power spectrum on large scales from the transmission fluctuations of the Lyman-alpha forest, which takes into account direc…
Lagrangian space consistency relation for large scale structure
Bart Horn, Lam Hui, Xiao Xiao
Consistency relations, which relate the squeezed limit of an (N+1)-point correlation function to an N-point function, are non-perturbative symmetry statements that hold even if the…
Analysis of Systematic Effects and Statistical Uncertainties in Angular Clustering of Galaxies from Early SDSS Data
SDSS Collaboration, Ryan Scranton, David Johnston +21
The angular distribution of galaxies encodes a wealth of information about large scale structure. Ultimately, the Sloan Digital Sky Survey (SDSS) will record the angular positions…
The impact of initial conditions on quasi-normal modes
Ameya Chavda, Macarena Lagos, Lam Hui
This study investigates the influence of initial conditions on the evolution and properties of linear quasi-normal modes (QNMs). Using a toy model in which the quasi-normal mode ca…
One-particle-irreducible consistency relations for cosmological perturbations
Walter D. Goldberger, Lam Hui, Alberto Nicolis
We derive consistency relations for correlators of scalar cosmological perturbations which hold in the "squeezed limit" in which one or more of the external momenta become soft. Ou…
Novel Probes of Gravity and Dark Energy
Bhuvnesh Jain, Austin Joyce, Rodger Thompson +29
The discovery of cosmic acceleration has stimulated theorists to consider dark energy or modifications to Einstein's General Relativity as possible explanations. The last decade ha…
Tests of Gravity Theories Using Supermassive Black Holes
Jeremy Sakstein, Bhuvnesh Jain, Jeremy S. Heyl +1
Scalar-tensor theories of gravity generally violate the strong equivalence principle, namely compact objects have a suppressed coupling to the scalar force, causing them to fall sl…
Tightening Constraints from the Lyman Alpha Forest with the Flux Probability Distribution Function
Adam Lidz, Katrin Heitmann, Lam Hui +3
The analysis of the Lyman-alpha forest of absorption lines in quasar spectra has emerged as a potentially powerful technique to constrain the linear matter power spectrum. In most…
Relativistic drag forces on black holes from scalar dark matter clouds of all sizes
Dina Traykova, Rodrigo Vicente, Katy Clough +4
We use numerical simulations of scalar field dark matter evolving on a moving black hole background to confirm the regime of validity of (semi-)analytic expressions derived from fi…
Symmetries of Vanishing Nonlinear Love Numbers of Schwarzschild Black Holes
Oscar Combaluzier-Szteinsznaider, Lam Hui, Luca Santoni +2
The tidal Love numbers parametrize the conservative induced tidal response of self-gravitating objects. It is well established that asymptotically-flat black holes in four-dimensio…
Twisting, reconnecting magnetospheres and magnetar spindown
Kyle Parfrey, Andrei M. Beloborodov, Lam Hui
We present the first simulations of evolving, strongly twisted magnetar magnetospheres. Slow shearing of the magnetar crust is seen to lead to a series of magnetospheric expansion…
A non-perturbative test of consistency relations and their violation
Angelo Esposito, Lam Hui, Roman Scoccimarro
In this paper, we verify the large scale structure consistency relations using N-body simulations, including modes in the highly non-linear regime. These relations (pointed out by…
An observational test of the Vainshtein mechanism
Lam Hui, Alberto Nicolis
Modified gravity theories capable of genuine self-acceleration typically invoke a galileon scalar which mediates a long range force, but is screened by the Vainshtein mechanism on…
The 3D Power Spectrum from Angular Clustering of Galaxies in Early SDSS Data
Scott Dodelson, Vijay K. Narayanan, Max Tegmark +22
Early photometric data from the Sloan Digital Sky Survey (SDSS) contain angular positions for 1.5 million galaxies. In companion papers, the angular correlation function an…
Static response and Love numbers of Schwarzschild black holes
Lam Hui, Austin Joyce, Riccardo Penco +2
We derive the quadratic action for the physical degrees of freedom of massless spin-0, spin-1, and spin-2 perturbations on a Schwarzschild--(A)dS background in arbitrary dimensions…
Constraining the Power Spectrum Using the Column Density Distribution: a Status Report
Lam Hui
We review the arguments for how the slope of the column density distribution of the Lyman-alpha forest should depend on the matter power spectrum. The latest progress, presented by…
Ladder Symmetries of Black Holes and de Sitter Space: Love Numbers and Quasinormal Modes
Roman Berens, Lam Hui, Zimo Sun
In this note, we present a synopsis of geometric symmetries for (spin 0) perturbations around (4D) black holes and de Sitter space. For black holes, we focus on static perturbation…
A Horizon Ratio Bound for Inflationary Fluctuations
Scott Dodelson, Lam Hui
We demonstrate that the gravity wave background amplitude implies a robust upper bound on the ratio: λ/ H^{-1} < e^60, where λis the proper wavelength of fluctuations of interest…
A Geometrical Test of the Cosmological Energy Contents Using the Lyman-alpha Forest
Lam Hui, Albert Stebbins, Scott Burles
In this Letter we explore a version of the test of cosmological geometry proposed by Alcock and Paczynski (1979), using observations of the Lyman-alpha forest in the spectra of clo…
Caustic fringes for wave dark matter
Andrew Eberhardt, Lam Hui
Wave dark matter is composed of particles sufficiently light that their de Broglie wavelength exceeds the average inter-particle separation. A typical wave dark matter halo exhibit…
Ladder Symmetries of Higher Dimensional Black Holes
Roman Berens, Lam Hui, Daniel McLoughlin +2
We compute the ladder operators for static tidal perturbations to higher-dimensional black holes. These operators map between solutions of the relevant equation of motion at differ…
The Angular Correlation Function of Galaxies from Early SDSS Data
SDSS Collaboration, Andrew Connolly, Ryan Scranton +22
The Sloan Digital Sky Survey is one of the first multicolor photometric and spectroscopic surveys designed to measure the statistical properties of galaxies within the local Univer…
Microcausality without Lorentz invariance
Lam Hui, Alberto Nicolis, Alessandro Podo +1
Microcausality -- the vanishing of commutators outside the lightcone -- is a fundamental property of relativistic quantum field theories. We derive its implications for two-point f…
Phenomenology of dark energy: general features of large-scale perturbations
Louis Perenon, Federico Piazza, Christian Marinoni +1
We present a systematic exploration of dark energy and modified gravity models containing a single scalar field non-minimally coupled to the metric. Even though the parameter space…
Weighing the Cosmological Energy Contents with Weak Gravitational Lensing
Lam Hui
Bernardeau et al. (1997), using perturbation theory, showed that the skewness of the large-scale lensing-convergence, or projected mass density, could be used to constrain ,…
Microlensing of gamma ray bursts by stars and MACHOs
Edward A. Baltz, Lam Hui
The microlensing interpretation of the optical afterglow of GRB 000301C seems naively surprising, since a simple estimate of the stellar microlensing rate gives less than one in fo…
Equation of State of the Photoionized Intergalactic Medium
Lam Hui, Nickolay Y. Gnedin
We develop an efficient method to study the effects of reionization history on the temperature-density relation of the intergalactic medium in the low density limit (overdensity le…
Introducing PHAEDRA: a new spectral code for simulations of relativistic magnetospheres
Kyle Parfrey, Andrei M. Beloborodov, Lam Hui
We describe a new scheme for evolving the equations of force-free electrodynamics, the vanishing-inertia limit of magnetohydrodynamics. This pseudospectral code uses global orthogo…
Short Distance Physics and the Consistency Relation for Scalar and Tensor Fluctuations in the Inflationary Universe
Lam Hui, William H. Kinney
Recent discussions suggest the possibility that short distance physics can significantly modify the behavior of quantum fluctuations in the inflationary universe, and alter the sta…
Challenges to the DGP Model from Horizon-Scale Growth and Geometry
Wenjuan Fang, Sheng Wang, Wayne Hu +3
We conduct a Markov Chain Monte Carlo study of the Dvali-Gabadadze-Porrati (DGP) self-accelerating braneworld scenario given the cosmic microwave background (CMB) anisotropy, super…
Constraining the Lifetime of Quasars from their Spatial Clustering
Zoltan Haiman, Lam Hui
The lifetime t_Q of the luminous phase of quasars is constrained by current observations to be between 10^6 and 10^8 years, but is otherwise unkown. We model the quasar luminosity…
Eötvös Experiments with Supermassive Black Holes
Asha Asvathaman, Jeremy S. Heyl, Lam Hui
By examining the locations of central black holes in two elliptical galaxies, M\,32 and M\,87, we derive constraints on the violation of the strong equivalence principle for purely…
Heating and scattering of stellar distributions by ultralight dark matter
Andrew Eberhardt, Mateja Gosenca, Lam Hui
Due to wave interference, an ultralight light dark matter halo has stochastic, granular substructures which can scatter stars, leading to the heating of stellar distributions. Stud…
Optimising the measurement of relativistic distortions in large-scale structure
Camille Bonvin, Lam Hui, Enrique Gaztanaga
It has been shown recently that relativistic distortions generate a dipolar modulation in the two-point correlation function of galaxies. To measure this relativistic dipole it is…
Lensing Bias in Cosmic Shear
Fabian Schmidt, Eduardo Rozo, Scott Dodelson +2
Only galaxies bright enough and large enough to be unambiguously identified and measured are included in galaxy surveys used to estimate cosmic shear. We demonstrate that because g…
The Lyman-alpha Forest: a Cosmic Gold Mine
Lam Hui
In recent years, a remarkably simple physical picture of the Lyman-alpha forest has emerged, which allows detailed predictions to be made and turns the forest into a powerful probe…
A Collapsar-Disk Origin for GW190814
Vishal Baibhav, Brian D. Metzger, Lam Hui
GW190814 was a remarkable gravitational-wave (GW) event: a merger between a 23 solar-mass black hole (BH) and a 2.6 solar-mass compact object, with an extreme mass ratio that is di…
Don't cross the streams: caustics from Fuzzy Dark Matter
Neal Dalal, Jo Bovy, Lam Hui +1
We study how tidal streams from globular clusters may be used to constrain the mass of ultra-light dark matter particles, called `fuzzy' dark matter (FDM). A general feature of FDM…
Nonlinearities in Black Hole Ringdowns
Keefe Mitman, Macarena Lagos, Leo C. Stein +11
The gravitational wave strain emitted by a perturbed black hole (BH) ringing down is typically modeled analytically using first-order BH perturbation theory. In this Letter we show…
The Thermal Memory of Reionization History
Lam Hui, Zoltan Haiman
The recent measurement by WMAP of a large electron scattering optical depth tau_e = 0.17 +- 0.04 is consistent with a simple model of reionization in which the intergalactic medium…
Black Hole Hair from Scalar Dark Matter
Lam Hui, Daniel Kabat, Xinyu Li +2
We show that a black hole surrounded by scalar dark matter develops scalar hair. This is the generalization of a phenomenon pointed out by Jacobson, that a minimally coupled scalar…
A New Mechanism for Bubble Nucleation: Classical Transitions
Richard Easther, John T. Giblin, Lam Hui +1
Given a scalar field with metastable minima, bubbles nucleate quantum mechanically. When bubbles collide, energy stored in the bubble walls is converted into kinetic energy of the…
On the streaming motions of haloes and galaxies
Ravi K. Sheth, Antonaldo Diaferio, Lam Hui +1
A simple model of how objects of different masses stream towards each other as they cluster gravitationally is described. The model shows how the mean streaming velocity of dark ma…
Likelihood Analysis of Galaxy Surveys
Scott Dodelson, Lam Hui, Andrew Jaffe
One of the major goals of cosmological observations is to test theories of structure formation. The most straightforward way to carry out such tests is to compute the likelihood fu…
On Estimating the QSO Transmission Power Spectrum
Lam Hui, Scott Burles, Uros Seljak +3
We present new methods to minimize the systematic and random errors for measuring the transmission power spectrum from the Lyman-alpha forest. Sources of systematic errors explored…
Quasi-Dilaton: Theory and Cosmology
Guido D'Amico, Gregory Gabadadze, Lam Hui +1
General Relativity (GR), with or without matter fields, admits a natural extension to a scale invariant theory that requires a dilaton. Here we show that the recently formulated ma…
Constraining the Rotation Rate of Transiting Extrasolar Planets by Oblateness Measurements
S. Seager, Lam Hui
(Abridged) The solar system gas giant planets are oblate due to their rapid rotation. A measurement of the planet's projected oblateness would constrain the planet's rotational per…
Single-Field Consistency Relations of Large Scale Structure. Part III: Test of the Equivalence Principle
Paolo Creminelli, Jérôme Gleyzes, Lam Hui +2
The recently derived consistency relations for Large Scale Structure do not hold if the Equivalence Principle (EP) is violated. We show it explicitly in a toy model with two fluids…
Biased-estimations of the Variance and Skewness
Lam Hui, Enrique Gaztanaga
Nonlinear combinations of direct observables are often used to estimate quantities of theoretical interest. Without sufficient caution, this could lead to biased estimations. An ex…
Cosmology with Minkowski functionals and moments of the weak lensing convergence field
Andrea Petri, Zoltán Haiman, Lam Hui +2
We compare the efficiency of moments and Minkowski functionals (MFs) in constraining the subset of cosmological parameters (Omega_m,w,sigma_8) using simulated weak lensing converge…
Correlated Fluctuations in Luminosity Distance and the (Surprising) Importance of Peculiar Motion in Supernova Surveys
Lam Hui, Patrick B. Greene
Large scale structure introduces two different kinds of errors in the luminosity distance estimates from standardizable candles such as supernovae Ia (SNe) - a Poissonian scatter f…
Power Spectrum Correlations Induced by Non-Linear Clustering
Roman Scoccimarro, Matias Zaldarriaga, Lam Hui
Gravitational clustering is an intrinsically non-linear process that generates significant non-Gaussian signatures in the density field. We consider how these affect power spectrum…
Inflationary soft theorems revisited: A generalized consistency relation
Lam Hui, Austin Joyce, Sam S. C. Wong
We reconsider the derivation of soft theorems associated with nonlinearly-realized symmetries in cosmology. Utilizing the path integral, we derive a generalized consistency relatio…
Correlations in the Lyman alpha forest: testing the gravitational instability paradigm
Matias Zaldarriaga, Uros Seljak, Lam Hui
We investigate correlations between the long wavelength fluctuations and the small scale power in the Lyman alpha forest. We show that such correlations can be used to discriminate…
Numerical and Perturbative Computations of the Fuzzy Dark Matter Model
Xinyu Li, Lam Hui, Greg L. Bryan
We investigate nonlinear structure formation in the fuzzy dark matter (FDM) model using both numerical and perturbative techniques. On the numerical side, we examine the virtues an…
Is Modified Gravity Required by Observations? An Empirical Consistency Test of Dark Energy Models
Sheng Wang, Lam Hui, Morgan May +1
We apply the technique of parameter-splitting to existing cosmological data sets, to check for a generic failure of dark energy models. Given a dark energy parameter, such as the e…
Scale-dependent halo bias from scale-dependent growth
Kyle Parfrey, Lam Hui, Ravi K. Sheth
We derive a general expression for the large-scale halo bias, in theories with a scale-dependent linear growth, using the excursion set formalism. Such theories include modified gr…
Massive-ish Particles from Small-ish Scales: Non-Perturbative Techniques for Cosmological Collider Physics from Large-Scale Structure Surveys
Samuel Goldstein, Oliver H. E. Philcox, J. Colin Hill +1
Massive particles produced during inflation impact soft limits of primordial correlators. Searching for these signatures presents an exciting opportunity to uncover the particle sp…
The Implications of a Pre-reionization 21 cm Absorption Signal for Fuzzy Dark Matter
Adam Lidz, Lam Hui
The EDGES experiment recently announced evidence for a broad absorption feature in the sky-averaged radio spectrum around 78 MHz, as may result from absorption in the 21 cm line by…
Effective field theory for hydrodynamics: thermodynamics, and the derivative expansion
Sergei Dubovsky, Lam Hui, Alberto Nicolis +1
We consider the low-energy effective field theory describing the infrared dynamics of non-dissipative fluids. We extend previous work to accommodate conserved charges, and we clari…
Unitarity Bounds and the Cuspy Halo Problem
Lam Hui
Conventional Cold Dark Matter cosmological models predict small scale structures, such as cuspy halos, which are in apparent conflict with observations. Several alternative scenari…
Conformal Symmetries of Adiabatic Modes in Cosmology
Kurt Hinterbichler, Lam Hui, Justin Khoury
We remark on the existence of non-linearly realized conformal symmetries for scalar adiabatic perturbations in cosmology. These conformal symmetries are present for any cosmologica…
Atmospheric Lensing and Oblateness Effects During an Extrasolar Planetary Transit
Lam Hui, Sara Seager
Future high precision photometric measurements of transiting extrasolar planets promise to tell us much about the nature of these systems. We examine how atmospheric lensing and (p…
High Energy Neutrinos From Superheavy Dark Matter Annihilation
Ivone F. M. Albuquerque, Lam Hui, Edward W. Kolb
Superheavy ( GeV) particles produced during inflation may be the dark matter, independent of their interaction strength. Strongly interacting superheavy particles will b…
Soft-Pion Theorems for Large Scale Structure
Bart Horn, Lam Hui, Xiao Xiao
Consistency relations -- which relate an N-point function to a squeezed (N+1)-point function -- are useful in large scale structure (LSS) because of their non-perturbative nature:…
Consistently constraining with the squeezed lensing bispectrum using consistency relations
Samuel Goldstein, Oliver H. E. Philcox, J. Colin Hill +2
We introduce a non-perturbative method to constrain the amplitude of local-type primordial non-Gaussianity () using squeezed configurations of the CMB lensing convergen…
How to Run Through Walls: Dynamics of Bubble and Soliton Collisions
John T. Giblin, Lam Hui, Eugene A. Lim +1
It has recently been shown in high resolution numerical simulations that relativistic collisions of bubbles in the context of a multi-vacua potential may lead to the creation of bu…
Emulating the CFHTLenS Weak Lensing data: Cosmological Constraints from moments and Minkowski functionals
Andrea Petri, Jia Liu, Zoltan Haiman +3
Weak gravitational lensing is a powerful cosmological probe, with non--Gaussian features potentially containing the majority of the information. We examine constraints on the param…