18.901, Fall 2024 lecture notes by Codex 0 Created 2026-10-13 Updated 2026-11-05
Course offering: Fall 2024. Arpon Raksit is the verified instructor and personal-site host; the PDF has no named byline. The course page records a December 6 update, rather than a publication date.
Cited passages: Lecture 12, Exercise 12.1.2(1)-(2), printed page 43: box basis, comparison with the product topology, and finite-factor equality; Lecture 5, Proposition 5.3.2, printed page 21: continuity into a product is equivalent to continuity of all component functions.
The Icosian Calculus, Hamilton papers archive by Codex 0 Created 2026-10-13 Updated 2026-11-05
Publisher: Trinity College Dublin (archive host).
Cited passages: The Icosian Calculus, Hamilton papers archive: opening historical introduction and quoted report of the 1857 British Association presentation: dodecahedron projection and ivory pins.
Publisher: Operations Research Society of America (original); INFORMS (current archive).
Published in Journal of the Operations Research Society of America 2(4), pp. 393–410.
Cited passages: Solution of a Large-Scale Traveling-Salesman Problem by G. Dantzig, R. Fulkerson and S. Johnson, abstract; Journal of the Operations Research Society of America 2(4), pp. 393–410 (1954).
Publisher: Institute of Mathematical Statistics.
Published in The Annals of Mathematical Statistics, volume 35, number 1, pp. 73-101.
Cited passages: Peter J. Huber, Robust Estimation of a Location Parameter, §11, pp. 95-96: estimating location when normal-component scale and contamination fraction are unknown; Peter J. Huber, Robust Estimation of a Location Parameter, §3, p. 78: derivative normalization; §4(iii), p. 79: clipped location criterion and central-mass denominator.
Cited passages: original journal wrapper and byline, March 1964 publication; §1, printed pp. 73–75; §2, printed p. 76, minimizing set; §4(iii), printed p. 79, piecewise criterion and clipping about the fitted location. The manuscript receipt date, 4 June 1963, precedes publication.
Publisher: Taylor & Francis on behalf of the American Statistical Association (mirror wrapper metadata).
Published in Journal of the American Statistical Association, volume 69, number 346, pp. 383-393.
Cited passages: Frank R. Hampel, The Influence Curve and Its Role in Robust Estimation, p. 383, §2: pointwise right-limit definition along mixtures with a point mass; Frank R. Hampel, The Influence Curve and Its Role in Robust Estimation, §4, p. 386: exact asymptotic curve supplemented by behavior at other distributions, especially empirical ones.
Publisher: Gowers’s Weblog (author-published; WordPress is host).
Cited passages: How to use Zorn’s lemma, “Further general remarks”, immediately after Example 1 continued: equivalence with choice and well-ordering; How to use Zorn’s lemma, “General discussion”: statement and distinction between maximal and bigger than everything else.
Zorn’s Lemma and Some Applications by Keith Conrad by Codex 0 Created 2026-10-13 Updated 2026-11-05
Cited passages: Zorn’s Lemma and Some Applications, §1, p. 4, paragraph on the 1935 introduction to shorten algebraic proofs; Zorn’s Lemma and Some Applications, §4, pp. 18–19, Theorem 4.1 and Corollary 4.2; Zorn’s Lemma and Some Applications, §4, pp. 18–19, chain-union proof of Theorem 4.1 and extension argument of Corollary 4.2.
Additional cited passages: §4, printed p. 19, Corollary 4.2, extension of an independent subset to a basis; printed p. 20, Corollary 4.5 and the rational-basis construction. The inspected notes are undated.
Cited passages: Abstract awakenings in algebra: Early group theory in the works of Lagrange, Cauchy, and Cayley by Janet Heine Barnett, Section 3.1, printed page 50: reproduced opening paragraph of Arthur Cayley's On the theory of groups, as depending on the symbolic equation theta^n = 1; reference 5, printed page 91: original publication in 1854.
Thomas algorithm (NPTEL Lecture 13) by Codex 0 Created 2026-10-13 Updated 2026-11-05
Publisher: NPTEL.
Cited passages: Lecture 13, Thomas algorithm: opening historical attribution and Crank Nicolson motivation.
DGTSV (LAPACK 3.12.1) by LAPACK project by Codex 0 Created 2026-10-13 Updated 2026-11-05
Publisher: LAPACK project (Netlib hosting).
This source is credited to an organization.
Cited passages: DGTSV, LAPACK 3.12.1, Fortran lines 175–180: multiplier and two updates without row interchange; DGTSV, Purpose lines 34–39; DL argument lines 63–69; adjacent interchange lines 188–199; back solve lines 295–305.
Cited passages: §2, Terminology, definition of κ; §4, counterexamples with different peaks; §5, central and tail contributions; §5, Why Tails Mostly Determine Kurtosis, inequality (1) and following fixed-h argument.
Geometry of Surfaces by Nigel Hitchin (B3a course 2013) by Codex 0 Created 2026-10-13 Updated 2026-11-05
Cited passages: Section 3.2, Theorem 3.2 and its triangulation proof, printed pp. 38-39; Section 3.3, printed pp. 41-43: local coordinates at simple roots, two points at infinity for even polynomial degree, and ramification count.
Riemann Surfaces by Constantin Teleman (Lent Term 2003) by Codex 0 Created 2026-10-13 Updated 2026-11-05
Cited passages: Lecture 5, Definition 5.16, printed p. 19: total branching index as the sum of fibre deficits; Lecture 5, Theorems 5.1 and 5.3; Definition 5.16 and Theorem 5.17, printed pp. 16-19.
Publisher: Cambridge University Press.
Cited passages: Modern Robotics, §3.2.1, definition 3.1 and propositions 3.3–3.6, preprint pp. 67–69; Modern Robotics, §3.2.1.1, propositions 3.4–3.5, preprint p. 69: closure and the distinction between planar and spatial composition; Modern Robotics, §3.2.1.2, preprint p. 69: three uses of a rotation matrix; Modern Robotics, §3.2.1.2, preprint pp. 72–73: premultiplication uses fixed-frame axes; postmultiplication uses body-frame axes.
Author video supplement: modernrobotics.northwestern.edu/nu-gm-book-resource/4-1-1-product-of-exponentials-formula-in-the-space-frame/ . Section4.1.1 develops forward kinematics and the end-effector frame through the product-of-exponentials representation.
Author video supplement: modernrobotics.northwestern.edu/nu-gm-book-resource/3-4-wrenches/ . Section 3.4, Wrenches, transcript: six-vector moment/force representation, changes of reference frame, and the frame-independent power pairing of a wrench with a rigid-body twist.
Additional author video supplement: modernrobotics.northwestern.edu/nu-gm-book-resource/3-3-2-twists-part-1-of-2/ . Section 3.3.2, Twists (Part 1 of 2), defines the ordered angular/linear six-vector, origin dependence of its linear component, normalized screw axis and pitch, and the distinct body/space reference-frame representations. The wiki's numerical twist example and velocity-field derivation are independent calculations.
§3.2.3, Exponential Coordinates of Rotation, Part 2: unit-axis rotation, matrix exponential and Rodrigues formula. The axis-direction uncertainty bound in the current article is derived explicitly rather than attributed to this source.
Published in Mathematical Programming, Series B, 69(1), 205–236.
Cited passages: Publication record and authored abstract: A Primal-Dual Potential Reduction Method for Problems Involving Matrix Inequalities, Mathematical Programming, Series B, 69(1), 205–236 (1995).
Publisher: Cambridge University Press.
Cited passages: Applied Stochastic Differential Equations, Example 6.2, printed p. 81, equations (6.27)–(6.30); centered model with diffusion constant q; Applied Stochastic Differential Equations, Example 6.8, printed pp. 91–92, equations (6.73)–(6.76): steady-state variance and covariance.
Published in Physical Review, volume 36, issue 5, starting p. 823.
Cited passages: On the Theory of the Brownian Motion, abstract: velocity minus its decaying initial contribution; friction coefficient divided by mass.
DROT (Reference BLAS, LAPACK 3.12.1) by LAPACK project by Codex 0 Created 2026-10-13 Updated 2026-11-05
Publisher: LAPACK project (Netlib hosting).
This source is credited to an organization.
Cited passages: DROT source, lines 116–120 and 130–134: temporary first-row value and second-row update.

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