One striking feature of Noether's 1929 paper occurred in a footnote: “As B. L. van der Waerden has communicated to me, one can obtain an invariant connection, independent of the specific choice of basis, by separating the concepts linear transformation and matrix. A linear transformation is a homomorphism of two modules of linear forms; a matrix is ( Read more... )

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Short proofs in Coq.

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Математические ( Read more... )

Recently I busied myself with finding a list of brackets and quotation characters and their correspondence in the Unicode Character Database. By “brackets” I mean all kinds of brackets: round, square, curly, etc. Though the database provides necessary information, it has some quirks.

( to be continued )

По-моему, никто не написал настоящую причину долгожительства Кобола. Причина не в том, что существует много программного кода на Коболе. Программист нужен только для того, чтобы писать новый программный код. Даже если он «дорабатывает» программу, он выбрасывает кусок кода и вписывает на его место новый. Это крайность, скажем, пишет новую функцию. ( Read more... )

I want to save this post for history. This was a question on Computer Science Stack Exchange, and it was deleted, but it is still an opinion and experience of a living programmer.

( to be continued )

Trying to measure the overhead cost of Linux system calls, I got the following strange result:

>./syscall.x ( Read more... )

In the course “DEV262x Logic and Computational Thinking” from Microsoft, students learn categorical syllogisms. How cute. I mean, Microsoft should know better.
Forms of Categorical Syllogisms ( Read more... )

In France, the discipline of logic has traditionally been ignored in university-level scientific studies. This follows, undoubtedly, from the recent history of mathe­matics in our country which was dominated, for a long while, by the Bourbaki school for whom logic was not, as we know, a strong point.

Krivine, Jean-Louis. Foreword. Mathematical ( Read more... )

I invite you to Secure Scuttlebutt (SSB), a serverless social network, where nobody can deprive you of the access to the network or delete your information and only you decide who to read and what to retransmit ( Read more... )