Morgan Arnold

MSc in Mathematics from EPFL, graduated 2026. BSc in Mathematics from UBC, graduated 2024. This blog obeys the (-, +, +, +) metric signature. Luddite. Politically left, and occasionally gauche.

MSc de Mathématiques à EPFL, diplômé 2026. BSc de Mathématiques à UBC, diplômé 2024. Ce blogue obéit la signature métrique (-, +, +, +). Luddite. De la gauche, et parfois gauche.

２０２６年に卒業したＥＰＦＬで大学院生だ。２０２４年に卒業したＵＢＣで大学生だ。このブロッグは(-, +, +, +)符号数を使う。ラッダイトだ。訳しにくいフランス語の洒落を省いた。

Website: https://morganarnold.net/
PGP Key: https://key.morganarnold.net/
Pronouns: he/him

Last Notes

2025-12-15 20:19:10 UTC

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i wouldn't call myself an expert, but my master's degree is in mathematical general relativity. at a glance, this doesn't look like any paper i've ever seen in mathematical general relativity. the researcher also appears to be employed by the research division of a mobile phone company, which makes me doubly suspicious. i can try to take a closer look later

2025-09-28 14:46:13 UTC

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okay, a couple of observations from computations. most probably aren't surprising.
first of all, light is blue-shifted rather than red-shifted. naturally, because there is no event horizon, there is no infinite red-shift at the event horizon.
as for orbits, the potential has no extrema, again somewhat unsurprisingly. although the singularity is naked, it isn't physically accessible, as the potential barrier goes to infinity near the singularity. gravitational lensing also isn't terribly surprising, although i struggle somewhat to visualise it! assuming the same impact parameter, you just get a sign change in the first-order approximation of the deflection, so instead of light rays being lensed around the black hole, they tend to be dispersed outward. maybe a better term here is gravitational mirroring? as best i can imagine, this sign reversal would make the black hole appear somewhat like a sort of weird spherical mirror. i wonder if i could hack into some computer simulation to better imagine what this would look like...

2025-02-14 08:24:18 UTC

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even if he doesn't succeed in cancelling existing grants, i can't imagine the chaos created by the fear and uncertainty. being canadian, i would really like to see our government move to make it easier for academics concerned about the trump administration interfering with their work to come to canada. i'm thinking about writing an op-ed to a large newspaper to try to advance the idea, although i feel woefully underinformed to try to write such a thing

2025-02-14 07:29:35 UTC

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this is enraging. i applied to the phd program at john's hopkins university last year (i was rejected, mind you, but anyway) specifically because i wanted to work with emily riehl. she's an incredible mathematician (and, i might add, an incredible asset to the american mathematical community)
i hope that she either finds a way to prevent the new administration from interfering with her work, or else is able to find a post as a university in a country in which ted cruz, who presumably hasn't has sat in a math class in thirty years, does not feel so confident as to claim that a grant supporting one of the foremost category theorists in the world is "government waste"

2024-10-03 20:42:40 UTC

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ah, what a shame! i don't really expect anyone else to pick up on (my) ilo, but if this is quite famous, it might be a good idea to rename. i'm taking the names for everything from toki pona (the assembler is "pali", the relocatable binary format is "poki", and the linker is probably going to be called "wan"), but even then, "ilo" is a bit of an awkward name for an isa, since an isa isn't really a "machine" or a "tool" in its own right, so much as it is a specification or a set of rules. "lawa" might actually be a better name for the isa itself!
as a side note, uxn was a huge inspiration for me to start thinking about isa design. the implementation of uxn's isa that i wrote was actually the first emulator that i ever wrote! i spent three months this summer backpacking in japan, and i kept a little notebook for scribbling ideas in, and ilo ended up kind of coalescing in that notebook out of ideas that i assimilated from uxn, risc-v, and a bunch of other isas. i suppose that what i'm trying to say is thank you for the inspiration that uxn provided!