Author Archives: Aronno Mirdha
Vega Through 600 Frames of Starlight
Tonight I pointed the Seestar S50 toward Vega and let it run for a while. Vega is one of those stars that almost feels too bright to photograph properly. It dominates the frame immediately, and after only a few exposures … Continue reading
Letter to the crew of Artemis II
Dear Artemis II crew, Good luck on your mission. What you are about to do is more than a flight. It is a step further into a place that, for most of us, only exists in equations and thought experiments. … Continue reading
Posted in Statements
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Inspiral-merger-ringdown consistency tests and the reconstruction of Kerr geometry
One of the more conceptually interesting developments in gravitational wave astronomy is the inspiral-merger-ringdown (IMR) consistency test. At a heuristic level, the idea is rather simple: different sectors of a binary black hole coalescence should reconstruct the same final spacetime … Continue reading
Posted in Expository, Notes
Tagged Astrophysics, Black holes, consistency tests, general relativity
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Traversable wormholes and the geometry of effective exoticity
One of the useful lessons of general relativity is that the Einstein equations are not, by themselves, especially conservative about the kinds of geometries they permit. Smooth Lorentzian metrics can describe black holes, gravitational waves, expanding cosmologies, singularity formation, and … Continue reading
A Dark Halo That Almost Became a Galaxy
One of the cleanest ideas in modern cosmology is also one of the easiest to overlook. According to the standard ΛCDM model, structure in the Universe forms hierarchically, with dark matter collapsing under gravity into bound halos over an enormous … Continue reading
A Consistency Test for Kerr Black Holes via Orbital Motion, Ringdown, and Imaging
Kerr Trisector Closure (KTC) is a consistency test for the Kerr hypothesis that tries to stay honest about what is actually being inferred from data. The guiding principle is simple: if the exterior spacetime of an astrophysical, stationary, uncharged black … Continue reading
Posted in Expository, Notes
Tagged consistency tests, general relativity, gravitational waves, KTC, theoretical physics
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Towards a derivation of the metric tensor in general relativity
One of the central tasks in differential geometry is to make precise the notion of length and angle on a smooth manifold. Unlike $\mathbb R^n$, a general manifold comes with no preferred inner product. The metric tensor is not something … Continue reading
Posted in Notes
Tagged differential geometry, general relativity, manifolds, riemannian geometry, theoretical physics
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Overdetermined parameter interference in physics
In many areas of physics, a system is described by a small number of fundamental parameters, while the available observations greatly exceed this number. When this occurs, the problem of parameter inference becomes overdetermined. Rather than being a drawback, this … Continue reading
Posted in Expository
Tagged consistency tests, general relativity, KTC
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The Kerr Trisector Closure: A project on internal consistency tests of General Relativity
General Relativity describes gravity as the curvature of spacetime. Mass and energy determine this curvature, and physical phenomena such as orbital motion, gravitational radiation, and the propagation of light are governed by the resulting geometry. In this framework gravity is … Continue reading
Posted in Expository, Projects
Tagged consistency tests, general relativity, gravitational waves, KTC
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Spacetime as a Lorentzian Manifold
One of the central tasks in differential geometry is to make precise the notion of length and angle on a smooth manifold. Unlike $\mathbb R^n$, a general manifold comes with no preferred inner product. The metric tensor is not something … Continue reading
Posted in Notes
Tagged differential geometry, general relativity, theoretical physics
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