Ciro Santilli @cirosantilli 40

If session autosave was finally mainlined, this would be Nirvana.

In Physics, in order to test a theory, you must be able to extract a number from it.

It does not matter how, if it is exact, or numerical, or a message from God: a number has to come out of the formulas in the end, and you have to compare it with the experimental data.

Many theoretical physicists seem to forget this in their lectures, see also: Section "How to teach and learn physics".

A single line in the emission spectrum.

So precise, so discrete, which makes no sense in classical mechanics!

Has been the leading motivation of the development of quantum mechanics, all the way from the:

You just map the value (1, 1) $C_m\times C_n$ to the value 1 of $C_{mn}$, and it works out. E.g. for $C_2\times C_3$, the group generated by of (1, 1) is:

It hasn't achieved anything beyond the Schengen zone.

Related:

Just like for the finite general linear group, the definition of special also works for finite fields, where 1 is the multiplicative identity!

Note that the definition of orthogonal group may not have such a clear finite analogue on the other hand.

Survey by Ciro Santilli: math.stackexchange.com/questions/1985/software-for-drawing-geometry-diagrams/3938216#3938216

Many plotting software can be used to create mathematics illustrations. They just tend to have more data-oriented rather than explanatory-oriented output.

Open source ones:

The Google Story Chapter 21. A Virtual Library mentions that Paul Allen was interested in trying to create something like the "Final Encyclopedia" from this book. This is somewhat the same motivation for Google Books and Google's activities more broadly, as shown in their organise the world's information mission statement.

Interesting presentation cycle at Merton BTW: www.arturekert.org/teaching/merton

Artur looks like a cool teacher.