Ciro Santilli @cirosantilli 40

Adds up chemical energy and kinetic energy.

Wikipedia mentions however that the kinetic energy is often negligible, even for gases.

The sum is of interest when thinking about reactions because chemical reactions can change the number of molecules involved, and therefore the pressure.

To predict if a reaction is spontaneous or not, negative enthalpy is not enough, we must also consider entropy via Gibbs free energy.

Bibliography:

When non-specialists say "Ethernet cable", they usually mean twisted pair for Ethernet over twisted pair.

But of course, this term is much more generic to a more specialized person, since notably fiber optics are also extensively used in Ethernet over fiber.

A useless piece of paper (or digital version of it) that you can pay taxes with :)

As opposed to:

This makes it clear how the Lie bracket can be seen as a "measure of non-commutativity"

Because the Lie bracket has to be a bilinear map, all we need to do to specify it uniquely is to specify how it acts on every pair of some basis of the Lie algebra.

Then, together with the Baker-Campbell-Hausdorff formula and the Lie group-Lie algebra correspondence, this forms an exceptionally compact description of a Lie group.

Polymorphism example:

The hello world!

general linear group over a finite field of order $m$. Remember that due to the classification of finite fields, there is one single field for each prime power $m$.

Exactly as over the real numbers, you just put the finite field elements into a $n\times n$ matrix, and then take the invertible ones.

Inward Bound by Abraham Pais (1988) page 282 shows how this can be generalized from the Maxwell-Boltzmann distribution

Ciro Santilli's birth country.

An awesome country, with amazing people and natural resources, and without an evil government like China.

When visiting Brazilian cities coming from Europe, one of the things that shocks the most is the amount of motorcycles. It seems that the poorer the country, the less people's lives are worth, and the more motorcycles there are.

Another thing that was shocking is the amount of phone spam when you get a new SIM card, some legal and some likely illegal. Everyone is desperate for cash it seems on a poor country, and everyone fights hard for it.

This is a good initiative. Since the government is incapable of doing shit in this area, individuals have to do it themselves.

They even have a scholarship program...: www.bolsas.gobrasa.org/

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