Oliver Knill

Twitter research

This is a test whether Twitter can be useful to spot results. As a corollary of a Cauchy-Binet generalization for pseudo determinants, there is an identity for classical determinants. Its a special case of a special case but maybe this is known. Can twitter find out?

Twitter proofs

In the summer of 2013, some experiments with Twitter proofs on 21a twitter. These are proofs in less than 140 characters (some of which are done using Mathematica).

Twitter in Course websites

It seems that Twitter is not very much used in higher education yet. I tried it out first in fall 2009 in math21a, then in spring 2010:

Fall 2009.
Local Copy [TXT].

Spring 2010
Local Copy [TXT] .

In my experience there are advantages and disadvantages:

  • The twitter feeds be embedded in a usual website
  • One can tweet from a handheld like the ipod and so make announcements to the class which are visible on the website while being on the road. This has advantages, because one does not want to have access to the website directly from a handheld (which one can lose).
  • One has to stay on the ball. It is easy to neglect the twitter account.
  • Like any blogging or social network service, it is not clear how long the service will be there. One has also to make backups to make sure that one has a long term backup. For me, any website is a document which I do not want to lose. Twitter does well now but it could be that in 5 years it is bought by Google or Microsoft or Yahoo, then crippled to death since such buyouts are often hostile with the only intention to kill some competition.


Oliver Knill, Department of Mathematics, Harvard University, One Oxford Street, Cambridge, MA 02138, USA. SciCenter 432 Tel: (617) 495 5549, Email: knill@math.harvard.edu. twitter. Spring 2013 office hours: Tuesday/Thursday 4-5 by Appointment, before and after classes.