The n-Category Café

Thanks very much! I hope my energy continues to be amazing, since I still have 2400 pages of This Week’s Finds to edit. Why did I write so much?

Thanks for checking! Maybe I started posting them on sci.physics before sci.physics.research was created.

If you did, they are not listed here (that’s apparently everything you posted in January 1993 to sci.physics.research).

Aha, here’s Week 3, in sci.math

Additional searching on sci.math and globally turned up nothing older than Week 3. The number of search results changes when simple parameters like the sorting of search results (relevance vs date), so it seems the searching algorithm is really badly behaved. And only certain search parameters even find Week 3, when it looks like all of the ones I tried should find it.

Here is Week 3 in sci.physics, though, for what it’s worth.

That’s great, Tom!

Scott and others will be glad to know that in editing the LaTeX version of This Week’s Finds I removed all the email addresses I saw. 1993 was a different age. There was no arXiv except for physics. At the time, it seemed perfectly reasonable to publish a mathematician’s email address so people could contact them for electronic preprints. I apologize for all the spam Scott has received in subsequent years.

In “week46”, written in December 1994, I chart the rise of the arXiv up to that point:

• High Energy Physics — Theory (hep-th), started 8/91

• High Energy Physics — Lattice (hep-lat), started 2/92

• High Energy Physics — Phenomenology (hep-ph), started 3/92

• Astrophysics (astro-ph), started 4/92

• Condensed Matter Theory (cond-mat), started 4/92

• General Relativity & Quantum Cosmology (gr-qc), started 7/92

• Nuclear Theory (nucl-th), started 10/92

• Chemical Physics (chem-ph), started 3/94

• High Energy Physics — Experiment (hep-ex), started 4/94

• Accelerator Physics (acc-phys), started 11/94

• Nuclear Experiment (nucl-ex), started 11/94

• Materials Theory (mtrl-th), started 11/94

• Superconductivity (supr-con), started 11/94

I also describe the brand new American Mathematical Society preprint server, which never caught on.

Later I announced the mathematics arXiv.

Thanks! I fixed it in my own files. Every so often I’ll release an improved version. But not very often. First I want to edit the remaining issues and put them on the arXiv.

It would be great if someone good at computers could automatically create a version with an index, or at least some sort of index of papers discussed. But I don’t have the energy to do that myself, at least not now. Besides TWFs, I want to write some books based on courses I’ve taught, starting with one on Lagrangian mechanics and one on category theory.

More minor glitches in week 40:

• quotation marks around “computer science”
• Journal of Philosophical Logic should be italicized
• use it up should be italicized instead of asterisked
• spacing and quotation marks around “at once”
• “by available at” in reference 2
• URL in reference 3 runs off the page

Fixed, thanks! I’ll update the copy on my website more often than the arXiv version, and your changes so far are there.

In “week40” I also changed “premiss” to “premise”, since I’m not really trying to pretend to be British.

One more! In week 35 (p. 176), there’s a parenthetical

(See “tangles”.)

that looks like it should point somewhere but doesn’t. It’s also a nonlink in the website version of TWF35. Looking back at the Usenet version, maybe the target was intended to be an older version of this page?

Yes, I must have been linking to that page. But I think I’ll just get rid of the link (except on my website, where I’ll fix it).

In the process I caught some more mistakes. There’s an endless number!

In week 37, top of page 186:

in the Bargmann [representation] multiplication

Punctuation of jointly-authored things is inconsistent in Week 38. It has “Ponzano-Regge” (hyphen) as well as “Turaev–Viro” (en dash) and “Turaev/Viro”.

In week 39 (p. 193), I think “DeRham cohomology” should be “de Rham cohomology”.

On p. 194, a preprint by Lisa C. Jeffrey is listed as “available from Princeton U. Mathematics Department”; it has coordinates arXiv:alg-geom/9404012.

In week 40, page 195, there’s an unbalanced quotation:

“computer science’

Week 43, page 213: “Bohm-Aharonov” should be “Bohm–Aharonov” to match convention (and the use earlier in the paragraph). Likewise, in week 44 (page 216), “Stiefel-Whitney” should be “Stiefel–Whitney”.

Week 48, page 233: For consistency with the paper title, the “$r$” in “$r$-matrices” should be in math mode.

Week 50, page 239: “Journal of Mathematical Physics” should be italicized. Page 240: “rotational symmetry [and] hence angular momentum”; the following sentence obeys conservation of apostrophes but needs a little rearrangement.

Thanks, Blake — that’s a nice lot of corrections.

I’ve been trying to change hyphens to en dashes in joint-authored concepts but I hadn’t caught all of them: now Ponzano–Regge, Bohm–Aharonov and Stiefel–Whitney are correct. The first appearance of the barbaric “Turaev/Viro” was in the abstract of someone else’s paper, but I’ve decided to use my authorial power and change even that one to “Turaev–Viro”.

I’ve always been a bit fuzzy about the correct spelling of “de Rham”, but you’re right. While I was at it, I also changed “Cech” to “Čech” and “Kaehler” to “Kähler”. I’d earlier fixed “Schrödinger” and “Gödel”.

It’s fun to reread these articles and see how much of the math I remember. The newly fixed version is here:

• http://math.ucr.edu/home/baez/TWF_1-50.pdf.

Here’s what I’ve got for the first 100 pages.

Week 1, page 4: two instances where a period and parenthesis should be exchanged since the parenthetical is part of the sentence, “time.)” and “UCR.)” Also, “Proc. Symp. in Pure Math.” should be italicized.

Week 4, pages 20–21:

(For a brief intro to functors and natural transformations, try the file “categories” in the collection of my expository papers — see the end of this post.)

Since the part at the end of the post has been deleted, perhaps this parenthetical should be too.

Week 5, page 24:

A whole book on 22 matrices??

Page 25: extra space in “finite- dimensional”.

Week 7, page 37: “r direction” should be “$r$ direction”.

Week 8, page 41: “Temperley Lieb” should be “Temperley–Lieb” (it’s in a quoted talk title, but now we’ve precedent for changing quotes). Space missing before publisher name in reference 2. “Journal of knot theory and its ramifications” should be italicized instead of quoted. Article titles should be quoted in reference 3.

Page 42: “require the consideration” should be “requiring the consideration”.

Page 43: “which can be obtained in a manner described at the end of this post” is obsolete.

Page 44: citation to Temperley and Lieb is formatted differently from the standard.

Week 9, page 45: “Mobius” should have an umlaut.

Week 10, page 51: “Discover” should be italicized, and the two book titles should be italicized instead of quoted.

Week 11, page 56: “Arnowitt-Deser-Misner” should be “Arnowitt–Deser–Misner”.

Week 12, page 59: “cf” should have a period.

Page 60: “Capovilla-Dell-Jacobson” should be “Capovilla–Dell–Jacobson”.

Week 14, page 68: “Wheeler-DeWitt” should be “Wheeler–DeWitt” (twice).

Week 15, page 74: “a vector field A” should be “a vector field $A$”.

Week 16, page 80: “dissasemble” should be “disassemble”.

Page 84: “Arnowitt-Deser-Misner” should be “Arnowitt–Deser–Misner”.

Page 86: “Capovilla-Dell-Jacobson” should be “Capovilla–Dell–Jacobson”.

Week 18, page 91: extra space after “Smolin”.

Week 19, page 96: “Week 5” is not hyperlinked.

Week 20, page 99: “ones lawn” should be “one’s lawn”.

Wow — thanks, Blake! I’ll make these changes later, but you will then be thanked in the preface!

One more batch! Now I can say that I have indeed gone through the entire document for typographical glitches at least. I’m very glad to help make the experience of reading TWF a little smoother.

Week 21, page 108: The book title “Knots and Physics” should be italicized instead of quoted. “Moebius” should get the umlaut treatment.

Page 111: space needed after “Mathematicians use the term”, and the quotation mark should be reversed. “Moebius” again.

Week 22, page 112: “Proceedings of the London Mathematical Society” should be italicized. Reference 3 is in an atypical format.

Week 24, page 124: space missing after “Thompson,”

Page 125: quotation mark before “what came before the big bang” has incorrect orientation and is unclosed.

Week 25, page 126: extraneous character in “Birkhauser” (maybe a corrupted a-with-umlaut?).

Pages 128 and 129: “Kac-Moody” should be “Kac–Moody”

Week 27, page 137: extraneous character in “Birkhauser” again.

Page 139: “Einstein-Podolsky-Rosen” should be “Einstein–Podolsky–Rosen”.

Week 28, page 148: missing quotation mark after “Kähler metric”; missing space and quotation mark in wrong orientation before “geodesic length functions”.

Week 29, page 150: extra comma in second item of reference list 1. Missing period after “eds” in third item. Extraneous space in “higher- dimensional”.

Week 30, page 153: “Wheeler-DeWitt” should be “Wheeler–DeWitt” (this is another that probably merits a global search for any instances that I’ve missed).

Page 154: “13-17” should be “13–17”. “Bad-Honnef” should be “Bad Honnef”.

Week 34, page 172: “Ashtekar-Sen” should be “Ashtekar–Sen”.

Thanks yet again! The new version is on my website!

An annoying feature of LaTeX installations with “smart quotes” is that when you type Birkh"auser, it converts the double quote into two separate single quotes, which creates an error.

One I missed: On page 4, “Zamolodhikov” should be “Zamolodchikov”.

It’s amazing how much communication methods have changed during the last 30 years or so. The future of communications seemed so rosy back then, before we thought hard about spam, cyber-warfare, propaganda, and the echo chamber effect.

Thanks! Yes, reading This Week’s Finds reminds me, too, of a happy bygone age. By the way, Michael Weiss, who coauthored the Photons, Schmotons thread, has recently been explaining nonstandard models of arithmetic to me in a similar long series of dialogues! So not everything from that bygone age is gone.

Thanks for the corrections. I have trouble believing I wrote “vluae” for “value”, but there it is. Now it’s fixed, I hope.