Chris Reiss, Justin C. Feng: Redshifted civilizations, galactic empires, and the Fermi paradox https://arxiv.org/abs/2510.00377 https://arxiv.org/pdf/2510.00377 https://arxiv.org/html/2510.00377
Chris Reiss, Justin C. Feng: Redshifted civilizations, galactic empires, and the Fermi paradox https://arxiv.org/abs/2510.00377 https://arxiv.org/pdf/2510.00377 https://arxiv.org/html/2510.00377
An appropriate song to end the week on:
m.youtube.com/watch?v=Y6lj...
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Immortality through the dark forces: Dark-charge primordial black holes as dark matter candidates. Jessica Santiago (National Taiwan University) et. al. https://arxiv.org/abs/2503.20696
Miguel Duarte, Justin C. Feng, Edgar Gasper\'in, David Hilditch
An asymptotic systems approach for the good-bad-ugly model with application to general relativity
https://arxiv.org/abs/2503.17036
Side eye monkey meme looking at the famous double slit experiment The monkey looks away from the experiment and the results suggest light is a wave The monkey looks at the experiment and the results suggest light is a particle
For me this is the best meme of all time and nothing else even comes close
Hi, I'm a general relativity/gravity postdoc at CEICO/FZU in Prague. Here's my orcid:
orcid.org/0000-0003-24...
Black and white photo of Einstein standing in front of shelves of papers and journals. His messy hair is dark - not yet the famous white shock that comes to mind when you hear his name. He is wearing dark pants and a dark cardigan with light trim. Einstein is looking at the camera but not smiling.
The intro of the paper reads (in German) Die Feldgleichungen der Gravitation. Von A. EiNSTEIN. In zwei vor kurzem erschienenen Mitteilungen' habe ich gezeigt, wie man zu Feldgleichungen der Gravitation gelangen kann, die dem Postulat allgemeiner RelativitΓ€t entsprechen, d. h. die in ihrer allgemeinen Fassung beliebigen Substitutionen der Raumzeitvariabeln gegenΓΌber ko-variant sind.
This passage shows the final field equations relating the Ricci tensor to the stress tensor with 1/2 of the trace removed.
Albert Einstein submitted "The Field Equations of Gravitation" to the Prussian Academy #OTD in 1915.
After years of work culminating in a frenzied month-long race against David Hilbert, Einstein had finally obtained the correct form of the field equations for general relativity. π§ͺ π βοΈ
(1/n)
With many physicists arriving daily at Bluesky Iβve created a comprehensive list -which I update daily- with Cosmologists, Astrophysicists, Gravitational Wave Astronomers, Particle Physicistsβ¦ Please SHARE so it reaches more people! π€© Warning: it may contain Mathematicians
bsky.app/profile/did:...
My previous institution is hiring:
academicjobsonline.org/ajo/jobs/29236
I am delighted that we our hosting the joint GR & Amaldi meetings in Glasgow in July 2025
Abstract registration is now open iop.eventsair.com/gr24-amaldi1...
The conference will cover gravitation, gravitational-wave and multimessenger astronomy, cosmology and relativistic astrophysics, and more!
I code in julia---does that count?
It still amazes me how straightforward it is to autodiff through numerical ODE solutions in julia.
Recently moved institutions to FZU - Institute of Physics of the Czech Academy in Prague.
This is a picture of the entrance to the new Solid State building (the main building where I work is in the back).
A few years ago, I came across a paper that more or less said the same thing:
arxiv.org/abs/1802.070...