bollu.github.io

This paper presents a self-replicating, homeostatic phenomenon called M0. M0 runs parasitically on populations of humans. It is remarkable in that although its anatomy is distributed across all phenomenological layers from neurological to paradigmattic, its causal sequences are robust and (once exposed) readily traceable and hence vulnerable to counterattack. The anatomy and lifecycle of the parasite are described, together with several secondary effects which are often of primary importance to the host population. An alternative interpretation of the role of dopamine in controlling mood and awareness is proposed, and how the “security breach” thus exposed is exploited by M0 is shown. A disturbing model of the variability of human consciousness is proposed.

Silent trade, also called silent barter, dumb barter (“dumb” here used in its old meaning of “mute”), or depot trade, is a method by which traders who cannot speak each other’s language can trade without talking. Group A would leave trade goods in a prominent position and signal, by gong, fire, or drum for example, that they had left goods. Group B would then arrive at the spot, examine the goods and deposit their trade goods or money that they wanted to exchange and withdraw. Group A would then return and either accept the trade by taking the goods from Group B or withdraw again leaving Group B to add to or change out items to create an equal value. The trade ends when Group A accepts Group B’s offer and removes the offered goods leaving Group B to remove the original goods.

we don’t have communities like we used to have with deep trust, even the families are not the same anymore. On the other hand I am not afraid to go to neighboring city (or when I was a kid it could be even other part of the city) so someone would come up with “hey you are not from around here, what are you looking for a trouble here son?”. We traded deep trust for broad trust. This way price of transactions on bigger scale went down a lot, even if they went up on personal or local level. In the end broad trust is more useful for people because it enables mobility. One can move to a big city and won’t be instantly scammed. If we would value deep trust only, there would be no way for people to move out from “dead end” places.

I will try to help with the title question. I think that the real motivation for the Levi-Civita connection comes from looking at surfaces in Euclidean 3-space. Differentate one tangent vector field Y along another X by first extending them to be defined in the ambient space, and then taking the tangential projection of XY, i.e. tangential projection of the Euclidean connection. Levi-Civita discovered that this process is intrinsic, i.e. invariant under isometry of surfaces without carrying along the ambient space, and described precisely by torsion freedom. This was clearly a long and difficult process. Dirac uses this view in his book General Theory of Relativity, and this is how I introduce the Levi-Civita connection in my lectures. I have to agree that there is something missing in the textbook discussions of torsion. I have not found an intuitive understanding of torsion.