Eric V. Linder
A5088626825- Cosmology and Gravitation Theories
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Galaxies: Formation, Evolution, Phenomena
- Dark Matter and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Stellar, planetary, and galactic studies
- Black Holes and Theoretical Physics
- Geophysics and Gravity Measurements
- Solar and Space Plasma Dynamics
- Pulsars and Gravitational Waves Research
- Astrophysics and Cosmic Phenomena
- Relativity and Gravitational Theory
- Adaptive optics and wavefront sensing
- Quantum Electrodynamics and Casimir Effect
- CCD and CMOS Imaging Sensors
- Superconducting and THz Device Technology
- Astro and Planetary Science
- History and Developments in Astronomy
- Space Science and Extraterrestrial Life
- Astronomical Observations and Instrumentation
- Computational Physics and Python Applications
- Statistical and numerical algorithms
- Scientific Research and Discoveries
- Advanced Thermodynamics and Statistical Mechanics
University of California, Berkeley
2016-2025
Berkeley College
2005-2025
Berkeley City College
2024-2025
Lawrence Berkeley National Laboratory
2015-2024
Nazarbayev University
2016-2024
Ewha Womans University
2009-2020
Korea Astronomy and Space Science Institute
2014-2020
Colorado School of Public Health
2019
University of Colorado Anschutz Medical Campus
2019
Ewha Womans University Medical Center
2011-2014
Exploring the recent expansion history of universe promises insights into cosmological model, nature dark energy, and potentially clues to high energy physics theories gravitation. We examine extent which precision distance-redshift observations can map out history, including acceleration-deceleration transition, components equations state density. consider ability distinguish between various dynamical scalar field models for as well higher dimension alternate gravity theories. Finally, we...
We present Advanced Camera for Surveys, NICMOS, and Keck adaptive-optics-assisted photometry of 20 Type Ia supernovae (SNe Ia) from the Hubble Space Telescope (HST) Cluster Supernova Survey. The SNe were discovered over redshift interval 0.623 < z 1.415. Of these Ia, 14 pass our strict selection cuts are used in combination with world's sample to derive best current constraints on dark energy. new 10 beyond = 1, thereby nearly doubling statistical weight HST-discovered this redshift. Our...
Spacetime curvature plays the primary role in general relativity but Einstein later considered a theory where torsion was central quantity. Just as Einstein-Hilbert action Ricci scalar $R$ can be generalized to $f(R)$ gravity, we consider extensions of teleparallel, or $T$, gravity $f(T)$ theories. The field equations are naturally second order, avoiding pathologies, and give rise cosmic acceleration with unique features.
The cosmic expansion history tests the dynamics of global evolution universe and its energy density contents, while growth inhomogeneous part density. Precision comparison two histories can distinguish nature physics responsible for accelerating expansion: an additional smooth component---dark energy---or a modification gravitational field equations. With aid new fitting formula linear perturbation accurate to 0.05%--0.2%, we separate out dependence on introduce index parameter...
We present evidence that the simplest particle-physics scalar-field models of dynamical dark energy can be separated into distinct behaviors based on acceleration or deceleration field as it evolves down its potential towards a zero minimum. show these occupy narrow regions in phase plane w and w', equation state time derivative units Hubble time. Restricting an scale microphysics limits how closely scalar resemble cosmological constant. These results, indicating desired measurement...
The Euclid space telescope will measure the shapes and redshifts of galaxies to reconstruct expansion history Universe growth cosmic structures. Estimation expected performance experiment, in terms predicted constraints on cosmological parameters, has so far relied different methodologies numerical implementations, developed for observational probes their combination. In this paper we present validated forecasts, that combine both theoretical expertise probes. This is presented provide...
We report a measurement of the B-mode polarization power spectrum in cosmic microwave background (CMB) using Polarbear experiment Chile. The faint signature carries information about universe's entire history gravitational structure formation, and inflation that may have occurred very early universe. Our covers angular multipole range 500 < ℓ 2100 is based on observations an effective sky area 25 with 35 resolution at 150 GHz. On these scales, lensing CMB by intervening universe expected to...
Gaussian processes provide a method for extracting cosmological information from observations without assuming model. We carry out cosmography -- mapping the time evolution of cosmic expansion in model-independent manner using kinematic variables and geometric probe cosmology. Using state art supernova distance data Union2.1 compilation, we constrain, any assumptions about dark energy parametrization or matter density, Hubble parameter deceleration as function redshift. Extraction these...
Dynamical dark energy has been recently suggested as a promising and physical way to solve the 3.4 sigma tension on value of Hubble constant $H_0$ between direct measurement Riess et al. (2016) (R16, hereafter) indirect constraint from Cosmic Microwave Anisotropies obtained by Planck satellite under assumption $\Lambda$CDM model. In this paper, parameterizing evolution using $w_0$-$w_a$ approach, considering $12$ parameter extended scenario, we find that: a) can indeed be solved with...
Abstract We implement Crossing Statistics to reconstruct in a model-agnostic manner the expansion history of universe and properties dark energy, using DESI Data Release 1 (DR1) BAO data combination with one three different supernova compilations (PantheonPlus, Union3, DES-SN5YR) Planck CMB observations. Our results hint towards an evolving emergent energy behaviour, negligible presence at z ≳ 1, varying significance depending on sets combined. In all these reconstructions, cosmological...
Dark energy has a dramatic effect on the dynamics of Universe, causing recently discovered acceleration expansion. The are also central to behaviour growth large-scale structure, offering possibility that observations structure formation provide sensitive probe cosmology and dark characteristics. In particular, with time-varying equation state can have an influence stretching back well into matter-dominated epoch. We analyse this impact, first calculating linear perturbation results,...
We investigate a f(R) modification of gravity that is exponential in the Ricci scalar R to explain cosmic acceleration. The steepness this dependence provides extra freedom satisfy solar system and other curvature regime constraints. With parameter alleviate usual fine tuning having strengthen near present, total number parameters only one more than LCDM. resulting class solutions asymptotes w=-1 but has no cosmological constant. calculate dynamics detail, examine effect on matter power...
The acceleration of the cosmic expansion may be due to a new component physical energy density or modification physics itself. Mapping scales and growth large scale structure in tandem can provide insights distinguish between two origins. Using Minimal Modified Gravity (MMG)---a single parameter gravitational index formalism parametrize modified gravity theories---we examine constraints that cosmological data place on nature physics. For next generation measurements combining weak lensing,...
Deviations from general relativity, such as could be responsible for the cosmic acceleration, would influence growth of large-scale structure and deflection light by that structure. We clarify relations between several different model-independent approaches to deviations relativity appearing in literature, devising a translation table. examine current constraints on deviations, using weak gravitational lensing data CFHTLS COSMOS surveys, microwave background radiation WMAP5, supernova...
Taking the Planck cosmic microwave background data and more direct Hubble constant measurement as unaffected by systematic offsets, values of $H_0$ interpreted within $\Lambda$CDM cosmological cold dark matter model are in $\sim 3.3 \sigma$ tension. We show that Parker vacuum metamorphosis model, physically motivated quantum gravitational effects with same number parameters $\Lambda$CDM, can remove tension, give an improved fit to (up $\Delta\chi^2=-7.5$). It also ameliorates tensions weak...
The ability to map the cosmological expansion has developed enormously, spurred by turning point one decade ago of discovery cosmic acceleration. standard model cosmology shifted from a matter dominated, gravity, decelerating present search for origin acceleration in expansion. We wide ranging review tools, challenges and physical interpretations. tools include direct measures scales through Type Ia supernova luminosity distances, angular distance baryon acoustic oscillation microwave...