What is... the nLab

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What is… the nLab?

Some thoughts. (See also: Wikipedia on the nLab)


Connect the relevant information.

We all waste too much time with searching for mathematical information that is already out there. As a student, before the dawn of the internet, I wasted days in the library, on chasing references to the secrets of the universe. Now the internet exists, but we still waste time searching randomly. Things have not been connected. The nnLab means to connect the dots. The idea is that you stop searching randomly and just follow the links. Hypertext. That was the original vision of the web. We need more research-level maths hypertext.

Show the big picture.

We are in an age where in theoretical physics we are supposed to work on quantum gravity and unification, needing the very latest of the developments in mathematics. At the same time we still bring up students with old textbooks. This way even the best of them at the end of their study can only grasp a tiny fraction of the big picture, because the knowledge is so scattered in tiny sub-expert communities. This is insane and unnecessary. The nnLab means to connect the dots and show the big picture. That’s why it’s organized by higher category theory. This is the structure that helps organize things and bring them together conceptually. (While of course many specific entries need not be category theoretic at all).

Tap the power of the swarm. Record.

Provide a place where all the notes that we all make merge and become better. Sometimes I see people proudly show me their private maths notebooks. Too bad that only one single person is profiting from it. We are an army of wheel-reinventers. (That’s necessary to some extent for personal exercise, but we’ll get nowhere if every single person retraces every single step. That has ended being sensible several hundred years ago.) At the same time people are eager to throw around information, such as on MathOverflow. The nnLab is to collect the stable bits, organized, hyperlinked, usefully.

Michael Polanyi in his ‘Personal Knowledge’ (1958) writes:

The transmission of mathematics has today been rendered more precarious than ever by the fact that no single mathematician can fully understand any longer more than a tiny fraction of mathematics. Modern mathematics can be kept alive only by a large number of mathematicians cultivating different parts of the same system of values: a community which can be kept coherent only by the passionate vigilance of universities, journals and meetings, fostering these values and imposing the same respect for them on all mathematicians. Such a far-flung structure is highly vulnerable and, once broken, impossible to restore. Its ruins would bury modern mathematics in an oblivion more complete and lasting than that which enveloped Greek mathematics twenty-two centuries ago.” (1958: 192-3)

See also around p. 31 of

Stop duplicating answers.

We all exchange lots of questions and answers on research over coffee, in emails etc. When the next person comes and asks the same question we repeat it. And next time again. That’s a waste of energy in a finite life. If you have an answer and you put it into the nnLab, next time you just link to it. For instance, whenever I want to say anything substantial on MathOverflow, I first put it on the nnLab (if it’s not already there) and then link to that in my answer.

(Which points to the main technical problem the nnLab has: it does not bathe your ego in +1s and badges.) (This is a joke.)

Revised on July 20, 2016 10:22:57 by Urs Schreiber (