Categoría: General

Just a short memo. We have seem that the sBoostrap, which is really a way to produce Chan-Paton labels, drives naturally to SU(15) and then perhaps to SO(30). Which was very encouraging because we know an open string needs to have a SO(32) group asociated to it. Sometimes this group is justifyed as 2^5, with…

La calle Nola tiene un estilo similar a la ciudad jardín, pero lleno de huertas que a vista aérea parecen todo patios interiores arbolados, solo que sin casas entre ellas, una limita con la siguiente, separadas por cuadrículas de muros. Desemboca -porque siendo onírica, no se sabe como se entra- en la acera derecha de…

  It is not rocket science… until it is. Se me estaba haciendo difícil entender el efecto o maniobra Oberth, porque siempre pienso que las maniobras asistidas incluyen intercambio de momento, y precisamente la pagina de la wikipedia arranca con un aviso «not to be confused with gravity assist». Sin intercambio de momento, la variación…

A couple weeks ago, the account @iwontoffendyou twitted the following problem. It was presented as a «round 1» exercise for employee interviews. So the logical path is first to try to answer either analytical or numerically, and only after a good enough answer is produced one can step back and look are more fun details.…

Thinking about a major puzzle in the NCG approach to the standard model, I remember that sci.physics.research, via Baez’ weeks, was very fond of triality (in the way of Evans?) to justify why some dimensions allow supersymmetry. And this pivots over SO(8), for which I asked a couple of abusive questions in mathoverflow: Does ??(32)???8×?8…