360 citations · 2.5k across the 52 of their papers we have counts for
30 papers · 1 filter
Action based approach to dissipative relativistic fluid systems
G. L. Comer, N. Andersson, T. Celora +1
We develop an action principle for a relativistic two-fluid system with dissipation. The specific constituents of the model - which serves as a proof of principle - are particles a…
A covariant approach to relativistic large-eddy simulations: The fibration picture
Thomas Celora, Nils Andersson, Ian Hawke +1
Models of turbulent flows require the resolution of a vast range of scales, from large eddies to small-scale features directly associated with dissipation. As the required resoluti…
Relativistic fluid dynamics: physics for many different scales
N. Andersson, G. L. C. Comer
The relativistic fluid is a highly successful model used to describe the dynamics of many-particle systems moving at high velocities and/or in strong gravity. It takes as input phy…
Linearizing a Non-linear Formulation for General Relativistic Dissipative Fluids
Thomas Celora, Nils Andersson, Greg L. Comer
Fully non-linear equations of motion for dissipative general relativistic multi-fluids can be obtained from an action principle involving the explicit use of lower dimensional matt…
A variational approach to relativistic superfluid vortex elasticity
N. Andersson, S. Wells, G. L. Comer
It is well known that a superfluid rotates by forming an array of quantized vortices. A relativistic formulation for superfluid vortex dynamics is required for a range of problems…
The dynamics of neutron star crusts: Lagrangian perturbation theory for a relativistic superfluid-elastic system
N. Andersson, B. Haskell, G. L. Comer +1
The inner crust of a mature neutron star is composed of an elastic lattice of neutron-rich nuclei penetrated by free neutrons. These neutrons can flow relative to the crust once th…
Beyond ideal magnetohydrodynamics: Resistive, reactive and relativistic plasmas
N. Andersson, K. Dionysopoulou, I. Hawke +1
We develop a new framework for the modelling of charged fluid dynamics in general relativity. The model, which builds on a recently developed variational multi-fluid model for diss…
Beyond ideal magnetohydrodynamics: From fibration to 3+1 foliation
N. Andersson, I. Hawke, K. Dionysopoulou +1
We consider a resistive multi-fluid framework from the 3+1 space-time foliation point-of-view, paying particular attention to issues relating to the use of multi-parameter equation…
A variational approach to resistive relativistic plasmas
N. Andersson, G. L. Comer, I. Hawke
We develop an action principle to construct the field equations for a multi-fluid system containing charge-neutral fluids, plasmas, and dissipation (via resistive interactions), by…
A covariant action principle for dissipative fluid dynamics: From formalism to fundamental physics
N. Andersson, G. L. Comer
We present a new variational framework for dissipative general relativistic fluid dynamics. The model extends the convective variational principle for multi-fluid systems to accoun…
The nonlinear development of the relativistic two-stream instability
I. Hawke, G. L. Comer, N. Andersson
The two-stream instability has been mooted as an explanation for a range of astrophysical applications from GRBs and pulsar glitches to cosmology. Using the first nonlinear numeric…
A minimal model for finite temperature superfluid dynamics
N. Andersson, C. Krueger, G. L. Comer +1
Building on a recently improved understanding of the problem of heat flow in general relativity, we develop a hydrodynamical model for coupled finite temperature superfluids. The f…
Cosmological Two-stream Instability
G. L. Comer, Patrick Peter, N. Andersson
Two-stream instability requires, essentially, two things to operate: a relative flow between two fluids and some type of interaction between them. In this letter we provide the fir…
Multi-fluid cosmology: An illustration of fundamental principles
G. L. Comer, Patrick Peter, N. Andersson
Our current understanding of the Universe depends on the interplay of several distinct "matter" components, which interact mainly through gravity, and electromagnetic radiation. Th…
Relativistic Two-stream Instability
L. Samuelsson, C. S. Lopez-Monsalvo, N. Andersson +1
We study the (local) propagation of plane waves in a relativistic, non-dissipative, two-fluid system, allowing for a relative velocity in the "background" configuration. The main a…
Matters of Gravity, The Newsletter of the Topical Group in Gravitation of the American Physical Society, Volume 31, Winter 2008
David Garfinkle, Greg Comer
GGR News: GGR program at the APS meeting in St. Louis we hear that... by David Garfinkle 100 years ago, by David Garfinkle Research Briefs: The Torsion Pendulum's Contribution to D…
Matters of Gravity, The Newsletter of the Topical Group in Gravitation of the American Physical Society, Volume 30, Fall 2007
David Garfinkle, Greg Comer
GGR News: -we hear that..., by David Garfinkle -News from the GRG Society, by Abhay Ashtekar -LIGO/GEO/Virgo work together, by Peter Saulson -GWIC Ten Years on, by Stan Whitcomb Re…
Oscillations of General Relativistic Multi-fluid/Multi-layer Compact Stars
Lap-Ming Lin, N. Andersson, G. L. Comer
We develop the formalism for determining the quasinormal modes of general relativistic multi-fluid compact stars in such a way that the impact of superfluid gap data can be assesse…
Relativistic Fluid Dynamics: Physics for Many Different Scales
N. Andersson, G. L. Comer
The relativistic fluid is a highly successful model used to describe the dynamics of many-particle, relativistic systems. It takes as input basic physics from microscopic scales an…
Superfluid Analog of the Davies-Unruh Effect
G. L. Comer
We produce an analog of the Davies-Unruh effect for superfluid helium four. There are two temperatures which result--one is associated with ordinary, or first, sound and the other…
Relativistic numerical models for stationary superfluid Neutron Stars
Reinhard Prix, Jerome Novak, G. L. Comer
We have developed a theoretical model and a numerical code for stationary rotating superfluid neutron stars in full general relativity. The underlying two-fluid model is based on C…
Slowly Rotating General Relativistic Superfluid Neutron Stars with Relativistic Entrainment
G. L. Comer
Neutron stars that are cold enough should have two or more superfluids/supercondutors in their inner crusts and cores. The implication of superfluidity/superconductivity for equili…
A Relativistic Mean Field Model for Entrainment in General Relativistic Superfluid Neutron Stars
G. L. Comer, R. Joynt
General relativistic superfluid neutron stars have a significantly more intricate dynamics than their ordinary fluid counterparts. Superfluidity allows different superfluid (and su…
Stationary structure of relativistic superfluid neutron stars
R. Prix, J. Novak, G. L. Comer
We describe recent progress in the numerical study of the structure of rapidly rotating superfluid neutron star models in full general relativity. The superfluid neutron star is de…