Siddharth Bhat

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1. Gregorian chant and numes
2. Decreasing Metric for Mutual Recursive Functions
3. FOL + Fixpoint + Counting does not capture P
4. Building an ELF by hand
5. Resolution is Refutation Complete
6. Fagin's theorem
7. EF (Ehrenfeucht–Fraïssé) games
8. DPLL
9. Why FOL models must be nonempty
10. Concrete calculation of hopf fibration
11. Canonical bundle over RP2 is not trivial
12. Concrete description of spinors
13. Paracompact spaces
14. Latin prefixes for words
15. Crash Course on Prosody
16. What the hell is a nix flake?
17. How to prove noConfusion
18. Origami box pleating
19. Vibes of Weiner Processes
20. Forward versus backward euler
21. Uniform Boundedness Principle / Banach Steinhauss
22. Coercive operator
23. It suffices to check for weak convergence on a spanning set.
24. Sequence that converges weakly but not strongly in $l^p$.
25. Axioms for definite integration
26. Quotient spaces of Banach space
27. Reisez Lemma
28. Using LLL to discover minimal polynomial for floating point number
29. Total Boundedness in a metric space
30. Holonomic v/s non holonomic constraints
31. The Plenoptic Function
32. Precision, Recall, and all that.
33. Heine Borel
34. The conceit of self loathing
35. Inverse scattering transform
36. Differentiating through sampling from a random normal distribution
37. BOSCC Vectorization
38. Autodiff
39. Vector Bundles and K theory, 1.1
40. Equicontinuity, Arzela Ascoli
41. Sobolev Embedding Theorem [WIP ]
42. Hahn Banach Theorem [WIP ]
43. Method of Characteristics [WIP ]
44. Eikonal Equation [WIP ]
45. Practical example of semidirect product
46. Algebraic graph calculus
47. Change of basis from triangle x y to barycentric
48. Lean4 access metam and so forth
49. Harmonic function
50. Lax Milgram theorem
51. Why L2 needs a quotient upto almost everywhere
52. Repulsive curves
53. Why NuPRL and Realisability makes it hard to communicate math
54. Lean does not allow nested inductive families
55. Weakly implicit arguments in Lean
56. Big list of elf file munging / linker / ABI
57. Regular epi and regular category
58. Focal point
59. Operational versus Denotational semantics
60. Minimising L2 norm with total constraint
61. Bounding L2 norm by L1 norm and vice versa
62. Example of unbounded linear operator
63. Direct sum of topological vector spaces
64. Subspaces need not have complement
65. $L^\infty$ is HUGE
66. Banach space that does not admit Schrauder basis
67. Open mapping theorem
68. Closed graph theorem
69. Bounded inverse theorem
70. Nonexistence of solutions for ODE and PDE
71. Baire Category Theorem
72. libOpenGL, libVDSO and Nix
73. Stuff I learnt in 2022
74. You don't know jack about data races
75. Training a custom model for Lean4
76. Stratified synthetsis
77. Mutual recursion elaboration in Lean
78. Subject reduction in Lean
79. Big list of GNU Binutils
80. Axiom K versus UIP
81. Linear vs uniqueness types
82. Any model of lean must have all inductives
83. Index over the past, fiber over the future
84. Type formers need not be injective
85. There cannot be a type of size the universe
86. The dependently typed expression problem
87. Motivation for modal logic
88. Scones
89. Presheaf models of type theory
90. Weighted limits via collages
91. Disjoint Coproduct
92. Leibniz Equality in Lean4
93. Strong normalization of STLC
94. Subobject classifiers of $N \to FinSet$, or precosheaf of $FinSet$
95. Dimensions versus units
96. HoTTesT: Identity types
97. Left and right adjoints to inverse image
98. Paredit via adjoints
99. Less than versus Less than or equals over Z
100. Allegories and Categories
101. Partial function as span
102. Turing degree
103. Proof that there is a TM whose halting is independent of ZFC
104. Contradiction from non-positive occurence
105. The constructible universe L
106. Godel completeness theorem
107. Uniform proofs, focused proofs, polarization, logic programming
108. Why cut elimination?
109. Forcing to add a function
110. Diaconescu's theorem
111. Forcing machinery
112. Partial Evaluation, Chapter 3
113. Partial Evaluation, Chapter 1
114. Diagonal lemma for monotone functions
115. Cantor Schroder Bernstein via fixpoint
116. Maximal Ideals of Boolean Algebras are Truth Values
117. Crash course on DCPO: formalizing lambda calculus
118. Resolution algorithm for propositional logic
119. Completeness for first order logic
120. Compactness theorem of first order logic
121. First order logic: Semantics
122. full abstraction in semantics
123. You could have invented Sequents
124. Fibrational category theory, sec 1.1, sec 1.2
125. Simple Type Theory via Fibrations
126. Realisability models
127. Naming left closed, right open with start/stop
128. Nested vs mutual inductive types:
129. Embedding HOL in Lean
130. Module system for separate compilation
131. Second order arithmetic
132. Lean4 Dev Meeting
133. Categorical model of dependent types
134. Coends
135. Natural Transformations as ends
136. Ends and diagonals
137. Parabolic dynamics and renormalization
138. Quantifiers as adjoints
139. TLDP pages for bash conditionals
140. Remainder, Modulo
141. Parameters cannot be changed anywhere , not just in return location
142. LCNF
143. Predicative v/s Impredicative: On Universes in Type Theory
144. Testing infra in Lean4
145. Autocompletion in Lean4
146. Inductive types
147. Parameter verus Index
148. HNF versus WHNF
149. Different types of arguments in Lean4:
150. Big list of lean tactics
151. Hyperdoctrine
152. Fungrim
153. Category where coproducts of computable things is not computable
154. Homotopy continuation
155. Relationship between linearity and contradiction
156. Monads from Riehl
157. Combinatorial Cauchy Schwarz
158. Bezout's theorem
159. Example for invariant theory
160. Counterexample to fundamental theorem of calculus?
161. Why a sentinel of -1 is sensible
162. Data structure to maintain mex
163. Scatted algebraic number theory ideas: Ramification
164. Coreflection
165. Better man Pages via info
166. The Zen of juggling three balls
167. Example of lattice that is not distributive
168. Patat
169. Common Lisp LOOP Macro
170. Mitchell-Bénabou language
171. Hyperdoctrine
172. Why is product in Rel not cartesian product?
173. simp in Lean4
174. Big list of Lean4 TODOS
175. unsafePerformIO in Lean4:
176. Big List of Lean4 FAQ
177. Sheaves in geometry and logic 1.2: Pullbacks
178. Sheaves in geometry and logic 1.3: Characteristic functions of subobjects
179. Common Lisp Debugging: Clouseau
180. Drawabox: Lines
181. Common Lisp Beauty: paths
182. Logical Predicates (OPLSS '12)
183. Logical Relations (Sterling)
184. Pointless topology: Frames
185. Introduction to substructural logics: Ch1
186. Integrating against ultrafilers
187. wegli: Neat tool for semantically grepping C++
188. Mostowski Collapse
189. Spaces that have same homotopy groups but not the same homotopy type
190. Fundamental group functor does not preserve epis
191. Epi in topological spaces
192. Permutation models
193. Almost universal class
194. Godel operations
195. Orthogonal Factorization Systems
196. Orthogonal morphisms
197. Locally Presentable Category
198. Remez Algorithm
199. Permission bits reference
200. Papers on Computational Group Theory
201. Kan Extensions: Key idea
202. Interleaved dataflow analysis and rewriting
203. Central variable as focal
204. Wilson's theorem
205. General enough special cases
206. XOR and AND relationship
207. Geometry of complex integrals
208. Green's functions
209. CP trick: writing exact counting as counting less than
210. CP trick: Heavy Light Decomposition euler tour tree
211. Counting with repetitions via pure binomial coefficients
212. Fundamental theorem of homological algebra [TODO ]
213. Projective modules in terms of universal property
214. How ideals recover factorization [TODO ]
215. Centroid of a tree
216. Path query to subtree query
217. Pavel: bridges, articulation points for UNDIRECTED graphs
218. Monadic functor
219. Injective module
220. Proof that $Spec(R)$ is a sheaf [TODO ]
221. Projections onto convex sets
222. LM algorithm for nonlinear least squares
223. Backward dataflow and continuations
224. Coordinate compression with set and vector
225. Hilbert polynomial and dimension
226. Cost of looping over all multiples of $i$ for $i$ in $1$ to $N$
227. Stuff I learnt in 2021
228. Cayley hamilton for 2x2 matrices in sage via AG
229. LispWorks config
230. Birkhoff Von Neumann theorem
231. Latin Square
232. Assignment Problem
233. Interpolating homotopies
234. Example where MIP shows extra power over IP
235. Lazy reversible computation?
236. Theorem coverage as an analogue to code coverage
237. Lazy GPU programming
238. Backward dataflow and continuations
239. The tyranny of structurelessness
240. Simple Sabotage Field Manual
241. Counting permutations with #MAXSAT
242. Coloring cat output with supercat
243. Reader monoid needs a hopf algebra?!
244. Monads mnemonic
245. Card stacking
246. SSH into google cloud
247. Comma & Semicolon in index notation
248. Spin groups
249. Undefined behaviour is like compactification [TODO ]
250. God of areppo
251. Classification of lie algebras, dynkin diagrams
252. Weird free group construction from adjoint functor theorem
253. bashupload
254. When are the catalan numbers odd
255. Geodesic equation, Extrinsic
256. Connections, take 2
257. Dropping into tty on manjaro/GRUB
258. Why the zero set of a continuous function must be a closed set
259. Derivatives in diffgeo
260. Building stuff with Docker
261. Lie derivative versus covariant derivative
262. The Tor functor
263. Sum of quadratic errors
264. Hip-Hop and Shakespeare
265. Write thin to write well
266. Hidden symmetries of alg varieties
267. fd for find
268. Thu Morse sequence for sharing
269. Elementary and power sum symmetric polynomials
270. Projective spaces and grassmanians in AG
271. Mnemonic for why eta is unit:
272. Fundamental theorem of galois theory
273. Counter-intuitive linearity of expectation [TODO ]
274. Metis
275. Tooling for performance benchmarking
276. Normal field extensions
277. Eisenstein Theorem for checking irreducibility
278. Gauss Lemma for polynomials
279. How GHC does typeclass resolution
280. Defining continuity covariantly
281. Why commutator is important for QM
282. Deriving pratt parsing by analyzing recursive descent [TODO ]
283. Level set of a continuous function must be closed
284. HPNDUF - Hard problems need design up front!
285. Separable Extension is contained in Galois extension
286. Primitive element theorem
287. Separable extension via embeddings into alg. closure
288. Separable extensions via derivation
289. Irreducible polynomial over a field divides any polynomial with common root
290. Galois extension
291. Separability of field extension as diagonalizability
292. Motivation for the compact-open topology
293. Example of covariance zero, and yet "correlated"
294. Hypothesis Testing
295. Dumb mnemonic for remembering adjunction turnstile
296. Delta debugging
297. Tidy Data
298. Normal subgroups through the lens of actions
299. Writing rebuttals, Tobias style
300. LCS DP: The speedup is from filtration
301. Poisson distribution
302. F1 or Fun : The field with one element
303. McKay's proof of Cauchy's theorem for groups [TODO ]
304. ncdu for disk space measurement
305. nmon versus htop
306. Schrier sims --- why purify generators times coset
307. Vyn's feeling about symmetry
308. Convergence in distribution is very weak
309. Class equation, P-group structure
310. Sylow Theorem 1
311. Fuzzing book
312. Fisher Yates
313. Bucchberger algorithm
314. GAP permutation syntax
315. Why division algorithm with multiple variables go bad
316. Integral elements of a ring form a ring [TODO ]
317. "Cheap" proof of euler characteristic
318. Siefert Algorithm [TODO ]
319. Cap product [TODO ]
320. Cup product [TODO ]
321. Colimits examples with small diagram categories
322. Limits examples with small diagram categories
323. Classification of compact 2-manifolds [TODO ]
324. Gauss, normals, fundamental forms [TODO ]
325. Second fundamental form
326. Theorem Egregium / Gauss's theorem (Integrating curvature in 2D) [TODO ]
327. Integrating Curvature in 1D [TODO ]
328. Fundamental theorem of symmetric polynomials
329. DP over submasks
330. Dual of Planar Euler graph is bipartite
331. Yoneda preserves limits
332. Separable Polynomials and extensions
333. Limits of a functor category are computed pointwise.
334. a + b = (a or b) + (a and b)
335. Intuition for why choosing closed-closed intervals of [1..n] is $(n+1)C2$
336. Thoughtful discussion on the limits of safe spaces
337. Semidirect product: Panning and Zooming
338. Longest Convex Subsequence DP
339. Representation theory of $SU(2)$ [TODO ]
340. Why quaternions work better
341. DFA to CFG via colimits?
342. Why pointless topology is powerful
343. Denotational semantics in a few sentences
344. Monge Matrix
345. Fixpoint as decorator
346. Combinatorial generation algorithms
347. Perform DP on measures, not indexes.
348. Alternative version of Myhill-Nerode
349. Polya Enumeration
350. Weighted Burnside Lemma
351. Cycle index polynomial
352. Mnemonics For Symmetric Polynomials
353. Uses of minimal string rotation
354. Suffix Automata
355. Simpson's Paradox
356. Myhill Nerode Theorem
357. Linearity of expectation for sampling
358. Min cost flow (TODO)
359. Clojure: minimal makefile for REPL driven dev with Neovim
360. Delimited continuations
361. Never forget monic again
362. Weird canonical example of monic and epic: left/right shift
363. Playing guitar: being okay with incorrect chords
364. Sparse table
365. Duval's algorithm
366. Amortized complexity from the verifier perspective
367. Relationship betwee permutations and runs
368. Brouwer's fixed point theorem
369. XOR on binary trie
370. Inconvergent: beautiful generative art
371. Prefix/Border function
372. Shortest walk versus shortest path
373. Minimal tech stack
374. FFT
375. codeforces rating of some GMs
376. Continuum TTRPG
377. Words to know in target language
378. DP on subarrays
379. Vis editor cheat sheet
380. Mean, Median and Jensen's
381. The similarity between labellings and representations
382. L1 norm is greater than or equal to L2 norm
383. Z algorithm
384. For a given recurrence, what base cases do I need to implement?
385. Number of distinct numbers in a partition
386. Splitting $f(x) = y$ into indicators
387. Why searching for divisors upto sqrt(n) works
388. Heuristics for the prime number theorem
389. Sum of absolute differences of an array
390. GCD is at most difference of numbers
391. implementing GCD and LCM
392. Centroid of a tree
393. Center of a tree
394. Image unshredding as hamiltonian path
395. Distance between lines in nD
396. lower_bound binary search with closed intervals
397. Sliding window implementation style
398. Kawaii implementation of x = min(x, y)
399. CSES: Counting Towers
400. Smallest positive natural which can't be represented as sum of any subset of a set of naturals
401. Example of RVs that are pairwise but not 3-way independent.
402. Notes on Liam O Connor's thesis: Cogent
403. C++ lower_bound, upper_bound API
404. Books that impart mental models
405. Subarrays ~= prefixes
406. Operations with modular fractions
407. Modular inverse calculation
408. The number of pairs (a,b) such that ab≤x is O(xlogx)
409. DP as path independence
410. Binary search to find rightmost index which does not possess some property
411. Correctness of lower_bound search with half-open intervals
412. Greedy Coin change: proof by probing
413. Clean way to write burnside lemma
414. The groupoid interpretation of type theory
415. Mnemonics for free = left adjoint
416. Where to scratch a cat
417. Mnemonic for Specht module actions
418. Quotes from 'Braiding Sweetgrass'
419. Transfinite recursion: Proof
420. Transfinite induction: Proof
421. Thoughts on playing Em-Bm
422. An explanation for why permutations and linear orders are not naturally isomorphic
423. We can't define choice for finite sets in Haskell!
424. Geomean is scale independent
425. Thoughts on playing Em Bm.
426. Induction on natural numbers cannot be derived from other axioms
427. Ordinals and cardinals
428. Musing about Specht modules
429. Every continuous function on $[a, b]$ attains a maximum
430. Invisible cities
431. Associativity of addition in cubicaltt
432. Etymology of fiber bundle $F \rightarrow E \rightarrow B$
433. Galois correspondence, functorially
434. CubicalTT: sharpening thinking about indexed functions
435. Functors to motivate adjuntions
436. Madoka Magica: plot thoughts
437. Chain rule functorially
438. Lagrange multipliers by algebra
439. Specht module construction
440. Even and odd functions through representation theory
441. Greg egan: Orthogonal
442. Simplicial approximation: maps can be approximated by simplicial maps (TODO)
443. Limit is right adjoint to diagonal
444. Working out why right adjoints preserve limits.
445. Limit/Colimit/Cone/Cocone: the arrows are consistent!
446. Representable Functors
447. Why terminal object is a limit
448. Excluded middle is not false in intuitionistic logic
449. Yoneda Lemma and embedding
450. GHCID
451. Character theory
452. Cofibration
453. Emily Riehl Contrability as uniqueness
454. Cofactor as derivative of determinant
455. Homology, the big picture
456. Legal Systems very different from ours
457. Shrinking wedge of circles / Hawaiian earring (TODO)
458. Simplicial approxmation of maps (TODO)
459. Lebesgue number lemma (TODO)
460. Lean internals Cheat Sheet
461. MicroUI
462. Proof of tree having (V-1) edges
463. Creating PDFs to read code
464. Bias and gain
465. Barycentric subdivision: edge length decreases
466. Homotopic maps produce same singular homology: Intuition
467. Singular homology: induced homomorphism
468. Demoscene tools
469. Binaural Beat
470. Low pass filter by delaying
471. Octaves are double frequency apart (TODO)
472. Bias and gain
473. Show, don't tell
474. Try and think of natural transformations as intertwinings
475. Subobject classifier measures how much we need to pay to access fact
476. Spectral norm of Hermitian matrix equals largest eigenvalue (TODO)
477. Penrose cohomology [TODO ]
478. Weingarten map
479. When maps cannot be lifted to the universal cover
480. Nets from Munkres (TODO)
481. Limit point compactness from Munkres
482. Proof of Heine Borel from Munkres (compact iff closed, bounded)
483. Alexandrov topology
484. Zeroth singular homology group: Intuition
485. Examples of fiber products / pullbacks
486. Covariant derivative
487. Clackety sounds: bucklespring
488. Submersions and immersions
489. Ehrsmann connection
490. Quotes from the culture
491. Lie bracket commutator as infinitesimal conjugation
492. Thoughts on proof of fundamental group of unit circle
493. Pasting lemma
494. Tensoring with base ring has no effect
495. Seeing the semidirect product of the dihedral group.
496. Animating rotations with quaternion curves
497. Mnemonic for hom-tensor and left-right adjoints
498. Construction of tensor product: Atiyah macdonald
499. Recovering topology from sheaf of functions: Proof from Atiyah Macdonald
500. Urhyson's lemma
501. Compact Hausdorff spaces are normal
502. Stone representation theorem: Proof from Atiyah Macdonald
503. Covariant Hom is left exact
504. Internal versus External semidirect products
505. Splitting of semidirect products in terms of projections
506. Tensor is right exact
507. Semidirect product as commuting conditions
508. Exact sequences for semidirect products; fiber bundles
509. Semidirect product is equivalent to splitting of exact sequence
510. Intro to topological quantum field theory
511. Non examples of algebraic varieties
512. Nilradical is intersection of all prime ideals
513. Exactness of modules is local
514. Quotient by maximal ideal gives a field
515. Ring of power series with infinite positive and negative terms
516. Mean value theorem and Taylor's theorem. (TODO)
517. Cayley Hamilton
518. Nakayama's lemma
519. Vector fields over the 2 sphere
520. Learning to talk with your hands
521. Lovecraftisms
522. Hairy ball theorem from Sperner's Lemma (TODO)
523. CS and type theory: Talks by vovodesky
524. Hilbert basis theorem for polynomial rings over fields (TODO)
525. Covering spaces
526. Wedge Sum and Smash Product
527. Quotient topology
528. CW Complexes and HEP
529. Stable homotopy theory
530. Simply connected spaces
531. Finitely generated as vector space v/s algebra:
532. Weak and Strong Nullstllensatz
533. Screen recording for kakoune pull request
534. Intuition for why finitely presented abelian groups are isomorphic to product of cyclics
535. Euler characteristic of sphere
536. John Conway: The symmetries of things
537. Semidirect product mnemonic
538. Non orthogonal projections
539. Why did maxwell choose his EM wave to be light?
540. Fast string concatenation in python3
541. Split infinitive
542. Yoneda from string concatenation
543. Right Kan extensions as extending the domain of a functor
544. Non standard inner products and unitarity of representations
545. take at most 4 letters from 15 letters.
546. Flat functions
547. Hopf Algebras and combinatorics
548. Butcher group
549. Neovim frontends
550. A semidirect product worked on in great detail
551. Direct and Inverse limits
552. LEAN 4 overfrom from LEAN together 2021
553. BLM master thesis
554. Hololive subculture
555. RSK correspondence for permutations
556. Djikstra's using a segtree
557. Markov and chebyshev from a measure theoretic lens
558. Among any 51 integers, that are 2 with squares having equal value modulo 100
559. $1^n + 2^n + \dots + (n-1)^n$ is divisible by $n$ for odd $n$
560. $10^{3n+1}$ cannot be written as sum of two cubes
561. Coq-club: the meaning of a specification
562. SQLite opening
563. Old school fonts
564. Stalking syzigies on hackernews
565. Conditional probability is neither causal nor temporal
566. Hook length formula
567. The tyranny of light
568. Muirhead's inequality
569. Rearrangement inequality
570. Triangle inequality
571. The Heather subculture
572. Frobenius Kernel
573. Galois theory by "Abel's theorem in problems and solutions"
574. Galois theory perspective of the quadratic equation
575. Burnside lemma by representation theory.
576. Contributing to SAGEmath
577. Shadow puppet analogy for entanglement
578. Books for contest math
579. Analysing simple games
580. Linear algebraic proof of the handshaking lemma
581. Historical contemporaries
582. Rota's twelvefold way
583. Counting necklackes with unique elements
584. Decomposition of projective space
585. Childhood: Playing pokemon gold in japanese
586. Tensor is a thing that transforms like a tensor
587. Tensor Hom adjunction
588. Schur's lemma
589. Daughters of destiny
590. Stuff I learnt in 2020
591. Line bundles, a high level view as I understand them today
592. Conversations with a wood carver
593. Discrete Riemann Roch
594. Conversation with Olaf Klinke
595. Topological groups and languages
596. The mnemonica stack (TODO)
597. Conversation with Alok about how I read
598. KMP (Knuth, Morris, Pratt) (TODO)
599. Reading C declarations
600. Make mnemonics
601. Vandermonde and FFT
602. Thoughts on blitz chess: 950 ELO
603. Periodic tables and make illegal states unrepresentable
604. questions on the structure of graphs
605. Combinations notation in bijective combinatorics
606. Arguments for little endian
607. Expectiles
608. Depth first search through linear algebra (TODO)
609. 2-SAT
610. Longest increasing subsequence, step by step (TODO)
611. On reading how to rule (TODO)
612. Strongly Connected Components via Kosaraju's algorithm
613. Articulation points
614. Disjoint set union
615. Making GDB usable
616. Bouncing light clock is an hourglass
617. Euler tours
618. Representation theory of the symmetric group (TODO)
619. Maximum matchings in bipartite graphs
620. p-adics, 2's complement, intuition for bit fiddling
621. Diameter of a tree
622. Catalan numbers as popular candidate votes (TODO)
623. The chromatic polynomial (TODO)
624. Structure theory of finite endo-functions
625. Number of paths in a DAG
626. Set partitions
627. Integer partitions: Recurrence
628. Stars and bars by direct bijection
629. DFS and topological sorting
630. Tournaments
631. Matching problems (TODO)
632. Four fundamental subspaces
633. WHO list of essential medicines (TODO)
634. why is int i = i allowed in C++?
635. Kakoune cheatsheet
636. Assembly IDE
637. Cohomology is like holism
638. Flows (TODO)
639. Amortized analysis
640. Shelly Kegan: death --- Suicide and rationality (TODO)
641. Sam harris and jordan peterson: Vancouver 1 (TODO)
642. Correctness of binary search
643. readlink -f to access file path
644. rank/select as compress/decompress
645. Remembering Eulerian and Hamiltonian cycles
646. Nice way to loop over an array in reverse
647. Dynamic Programming: Erik Demaine's lectures
648. Accuracy vs precision
649. Why is the gradient covariant?
650. Politicization of science
651. Multi ꙮ cular O: ꙮ / Eye of cthulu
652. You can't measure the one way speed of light
653. Show me the hand strategy
654. Words that can be distinguished from letters if we know the sign of the permutation
655. Easy times don't create weak people, they just allow weak people to survive.
656. Multiplicative weights algorithm (TODO)
657. How to fairly compare groups
658. Bijection from (0, 1) to [0, 1]
659. Rene Girard
660. Noam Chomsky on anarchism (TODO)
661. Slavoj Zizek: Violence
662. Poverty: Who's to blame?
663. Learn Zig in Y minutes
664. The algebraic structure of the 'nearest smaller number' question
665. Why loss of information is terrifying: Checking that a context-free language is regular is undecidable
666. Sciences of the artificial
667. Numbering nodes in a tree
668. Number of vertices in a rooted tree
669. Median minimizes L1 norm
670. LISP quine
671. A slew of order theoretic and graph theoretic results
672. Neko to follow your cursor around
673. Non commuting observables: Light polarization
674. Statement expressions and other GCC C extensions
675. A quick look at impredicativity
676. Data oriented programming in C++
677. Retro glitch
678. SSA as linear typed language
679. Nix weirdness on small machines
680. Autodiff over derivative of integrals
681. Proof of projective duality
682. Preventing the collapse of civilization
683. Violent deaths in ancient societies (TODO)
684. An elementary example of a thing that is not a vector
685. Elementary probability theory (TODO)
686. The handshaking lemma
687. Git for pure mathematicians
688. Mutorch
689. Computing the smith normal form
690. Laziness for C programmers
691. Exact sequence of pointed sets
692. What is a syzygy?
693. Under the spell of Leibniz's dream
694. Normal operators: Decomposition into Hermitian operators
695. Readable pointers
696. The grassmanian, handwavily
697. Lie bracket as linearization of conjugation
698. Computational Origami
699. Katex in duktape
700. Kebab case
701. Localization: Introducing epsilons (TODO)
702. NaN punning: Storing integers in doubles in JavaScript
703. Offline Documentation
704. Using Gurobi
705. osqp: convex optimizer in 6000 LoC
706. stars and bars by generating functions
707. This is not a place of honor
708. Topological proof of infinitude of primes
709. Burnside Theorem
710. The Ise Grand shrine
711. Edward Kmett's list of useful math
712. Cokernel is not sheafy
713. Von neumann: foundations of QM
714. Discrete schild's ladder
715. Derivative of step is dirac delta
716. Extended euclidian algorithm
717. In a PID, all prime ideals are maximal, geometrically
718. Prime numbers as maximal among principal ideals
719. Axiom of Choice and Zorn's Lemma
720. Local ring in terms of invertibility
721. Nullstellensatz for schemes
722. Perspectives on Yoneda
723. Germs, Stalks, Sheaves of differentiable functions
724. Connectedness in terms of continuity
725. Intuition for limits in category theory
726. Finite topologies and DFS numbering
727. Categorical definition of products in painful detail
728. Why is the spectrum of a ring called so?
729. Ergo proxy
730. Satisfied and frustrated equations
731. Combinatorial intuition for Fermat's little theorem
732. An incorrect derivation of special relativity in 1D
733. The geometry and dynamics of magnetic monopoles
734. Sanskrit and Sumerian
735. Writing Cuneiform
736. The code of hammurabi
737. The implicit and inverse function theorem
738. Whalesong hyperbolic space in detail
739. Motivating Djikstra's
740. Intuitions for hyperbolic space
741. Product of compact spaces in compact
742. Hyperbolic groups have solvable word problem
743. Elementary uses of Sheaves in complex analysis
744. Snake lemma
745. Kernel, cokernel, image
746. The commutator subgroup
747. Simplicity of A5 using PSL(2, 5)
748. A5 is not solvable
749. Complex orthogonality in terms of projective geometry
750. Arithmetic sequences, number of integers in a closed interval
751. The arg function, continuity, orientation
752. Odd partitions, unique partitions
753. Continued fractions, mobius transformations
754. Permutations-and-lyndon-factorization
755. Graphs are preorders
756. Parallelisable version of maximum sum subarray
757. Thoughts on implicit heaps
758. Discriminant and Resultant
759. Polynomial root finding using QR decomposition
760. A hacker's guide to numerical analysis
761. Mobius inversion on Incidence Algebras
762. Finite differences and Umbral calculus
763. Permutahedron
764. Lyndon + Christoffel = Convex Hull
765. Geometric proof of e^x >= 1+x, e^(-x) >= 1-x
766. Ranking and Sorting
767. Proof of minkowski convex body theorem
768. Burrows Wheeler
769. Intuitionstic logic as a Heyting algebra
770. Edit distance
771. Evolution of bee colonies (TODO)
772. Best practices for array indexing
773. Algebraic structure for vector clocks
774. Networks are now faster than disks
775. Einstein-de Haas effect
776. Rank-select as adjunction
777. Bounding chains: uniformly sample colorings
778. Coupling from the past
779. Word problems in Russia and America
780. Encoding mathematical hieararchies
781. Learning code by hearing it
782. Your arm can be a spinor
783. Self modifying code for function calls: Look ma, I don't need a stack!
784. Adjunctions as advice
785. Reversible computation as groups on programs
786. Blazing fast math rendering on the web
787. VC dimension
788. Symplectic version of classical mechanics
789. Theorems for free
790. How to reason with half-open intervals
791. How does one build a fusion bomb?
792. Christoffel symbols, geometrically
793. A natural vector space without an explicit basis
794. Cache oblivious B trees
795. Krohn-Rhodes decomposition
796. Proving block matmul using program analysis
797. Why I like algebra over analysis
798. using for cleaner function type typedefs
799. A walkway of lanterns (TODO)
800. Natural transformations
801. The hilarious commentary by dinosaure in OCaml git
802. How to link against MLIR with CMake
803. Energy as triangulaizing state space
804. The cutest way to write semidirect products
805. My Favourite APLisms
806. Proof of chinese remainder theorem on rings
807. monic and epic arrows
808. The geometry of Lagrange multipliers
809. Efficient tree transformations on GPUs (TODO)
810. Things I wish I knew when I was learning APL
811. Every ideal that is maximal wrt. being disjoint from a multiplicative subset is prime
812. Getting started with APL
813. SpaceChem was the best compiler I ever used
814. Mnemonic for Kruskal and Prim
815. Legendre transform
816. Cartesian Trees
817. DFS numbers as a monotone map
818. Self attention? not really
819. Coarse structures
820. Matroids for greedy algorithms (TODO)
821. Grokking Zariski
822. My preferred version of quicksort
823. Geometric proof of Cauchy Schwarz inequality
824. Dataflow analysis using Grobner basis
825. Fenwick trees and orbits
826. Dirichlet inversion
827. Incunabulum for the 21st century: Making the J interpreter compile in 2020
828. An example of a sequence whose successive terms get closer together but isn't Cauchy (does not converge)
829. Krylov subspace method
830. Good reference to the Rete pattern matching algorithm
831. Leapfrog Integration
832. Comparison of forward and reverse mode AD
833. An invitation to homology and cohomology, Part 1 --- Homology
834. An invitation to homology and cohomology, Part 2 --- Cohomology
835. Stuff I learnt in 2019
836. A motivation for p-adic analysis
837. Line of investigation to build physical intuition for semidirect products
838. Topology is really about computation --- part 2
839. Topology is really about computation --- part 1
840. PSLQ algorithm: finding integer relations between reals
841. Geometric characterization of normal subgroups
842. Handy characterization of adding an element into an ideal, proof that maximal ideal is prime
843. Radical ideals, nilpotents, and reduced rings
844. My disenchantment with abstract interpretation
845. Computing equivalent gate sets using grobner bases
846. The janus programming language --- Time reversible computation
847. A = B --- A book about proofs of combinatorial closed forms
848. Generating k bitsets of a given length n:
849. Bondi k-calculus
850. Topology as an object telling us what zero-locus is closed:
851. Vivado toolchain craziness
852. What the hell is a Grobner basis? Ideals as rewrite systems
853. Lie bracket versus torsion
854. Blog post: Weekend paper replication of STOKE, the stochastic superoptimizer
855. Collapsing BlockId, Label, Unique:
856. Spatial partitioning data structures in molecular dynamics
857. Vector: Arthur Whitney and text editors
858. Representing CPS in LLVM using the @coro.* intrinsics
859. Bug in the LLVM code generator: Lowering of MO_Add2 and MO_AddWordC
860. Discrete random distributions with conditioning in 20 lines of haskell
861. Everything you know about word2vec is wrong
862. Hamiltonian monte carlo, leapfrog integrators, and sympletic geometry
863. Small Haskell MCMC implementation
864. The smallest implementation of reverse mode AD (autograd) ever:
865. Timings of passes in GHC, and low hanging fruit in the backend:
866. Varargs in GHC: T7160.hs
867. Debugging debug info in GHC
868. GHC LLVM code generator: Switch to unreachable
869. Concurrency in Haskell
870. Handy list of differential geometry definitions
871. Lazy programs have space leaks, Strict programs have time leaks
872. Presburger arithmetic can represent the Collatz Conjecture
873. Using compactness to argue about covers
874. Japanese Financial Counting system
875. Stephen wolfram's live stream
876. Cleave as a word has some of the most irregular inflections
877. McCune's single axiom for group theory
878. Word2Vec C code implements gradient descent really weirdly
879. Arthur Whitney: dense code
880. How does one work with arrays in a linear language?
881. Linear optimisation is the same as linear feasibility checking
882. Quantum computation without complex numbers
883. Linguistic fun fact: Comparative Illusion
884. Long-form posts:
885. Emacs Cheat Sheet
886. Coq Cheat Sheet
887. Writing Cheat Sheet
888. Latex Cheat Sheet
889. Architecture Cheat Sheet
890. Recipes Cheat Sheet
891. History Cheat Sheet
892. Words Cheat Sheet
893. Clojure Sheat Sheet
894. Big list of quotes
895. Empathy
896. Vim Cheat Sheet
897. Big list of Chess
898. Big list of shitposting
899. Big list of Breakdance
900. Big list of Cardistry
901. Poems to memorize
902. X86 Cheat Sheet
903. Common Lisp Cheat Sheet
904. Agda Cheat Sheet
905. Don't Try
906. Big list of Hacker news
907. Hair in a bun with stick
908. Big list of shuffle dancing
909. Big list of tmux
910. Big list of new words
911. Favourite OP1 tutorials
912. Favourite Demoscenes
913. Classical music
914. Blues and Jazz Piano Improv
915. All about the C minor scale
916. Sheet Music