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This is the construction / computation page for my joint paper with Roland van der Veen:
A Perturbed-Alexander Invariant.
Dedicated to the memory of V. F. R. Jones, 1952-2020, a friend and a mentor.
Paper PDF here: APAI.pdf. Computations here: APAI.nb.
Abstract. In this note we give concise formulas, which lead to a simple and fast computer program that computes a powerful knot invariant. This invariant $\rho_1$ is not new, yet our formulas are by far the simplest and fastest: given a knot we write one of the standard matrices $A$ whose determinant is its Alexander polynomial, yet instead of computing the determinant we consider a certain quadratic expression in the entries of $A^{-1}$. The proximity of our formulas to the Alexander polynomial suggest that they should have a topological explanation. This we don't have yet.
Archive Data figs Snips / Talks: Geneva-2206 Talks: Waco-2203 SlideShow2.html SlideShow.html / APAI@230322.pdf APAI-Dev.pdf APAI.pdf APAI-Scratch.pdf Notebook.pdf / G&T Decision.txt QT_Report_2.txt QT_Report.txtNotebook (.pdf) | Source (.nb) | Created | Last Modified | Summary | |
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1 | AAT | source | 2023-01-03 11:17:25 | 2023-01-04 03:16:05 | $A$ - $A^T$ experiments. |
2 | AlexanderExperiments | source | 2022-09-22 14:33:05 | 2022-09-25 14:14:25 | Alexander Experiments: Modifying the A Matrix. |
3 | APAI-Expand | source | 2022-09-13 20:29:10 | 2022-09-14 03:27:52 | Same as APAI.nb, but with Expand replacing Factor. |
4 | APAI - Other R | source | 2022-09-19 14:57:39 | 2022-09-19 15:50:56 | Mathematica notebook for A Perturbed Alexander Invariant, with revised Rs. |
5 | APAI | source | 2022-01-08 08:25:07 | 2023-03-21 21:43:39 | Mathematica notebook for A Perturbed Alexander Invariant. |
6 | GGbar | source | 2023-01-13 05:23:20 | 2023-01-13 08:45:52 | Failed $G$ - $\bar{G}$ experiments. |
7 | GGI | source | 2023-01-04 02:45:05 | 2023-01-04 03:31:12 | Failed $G$ - $G-I$ experiments. |
8 | GGT | source | 2023-04-20 15:37:06 | 2023-04-20 15:58:25 | Comparing $G$ and $G^T$. |
9 | GST48 | source | 2022-02-05 17:14:56 | 2022-02-05 18:02:17 | |
10 | index | source | 2022-06-24 12:26:51 | 2022-06-24 12:50:30 | This is the index file for the APAI project. |
11 | Invariance2 | source | 2022-02-17 11:15:55 | 2022-02-17 11:15:56 | Invariance proof by Roland. |
12 | Invariance-Scratch | source | 2022-05-25 09:37:14 | 2022-06-02 16:39:47 | |
13 | Lashings-230105 | source | 2023-03-02 19:21:44 | 2023-01-05 07:56:03 | The Lashings Matrix. |
14 | Lashings | source | 2023-01-04 07:41:08 | 2023-04-20 14:34:40 | The Lashings Matrix. |
15 | MakeData3-14 | source | 2022-02-14 09:32:49 | 2022-02-14 11:15:42 | Compute and store ρ, Kh, and HOMFLYPT for knots with up to 14 crossings |
16 | Make | source | 2022-01-09 22:23:29 | 2022-06-24 06:19:39 | |
17 | OtherAlexanders | source | 2022-01-23 18:14:22 | 2022-01-25 13:45:12 | Other near-Wirtinger matrices to produce the Alexander polynomial. |
18 | PABI-InBack | source | 2022-01-07 14:06:43 | 2022-01-12 07:16:02 | Perturbed Alexander-Burau Invariants. Continues Pensieve://2021-12/, but with the perturbation placed ahead of the bulk. |
19 | Playing-220818 | source | 2022-08-18 09:21:56 | 2022-08-18 09:40:19 | Playing near $\rho_1$. |
20 | Rho1-3-100 | source | 2022-01-06 12:05:01 | 2022-01-07 09:29:25 | Perturbed Alexander-Burau Invariants. DPG code from PerturbedHeisenberg2.nb at pensieve://Classes/21-1350-KnotTheory/. Continued pensieve://Projects/APerturbedAlexanderInvariant/. |
21 | Rot | source | 2022-05-24 10:23:57 | 2022-05-24 10:24:29 | Computing rotation numbers. Based on Common.nb at pensieve://Classes/21-1350-KnotTheory/. |
22 | TimingGST48 | source | 2022-06-16 11:10:35 | 2022-06-17 05:42:04 |