Apr 2007 BLOG

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2007-04-30 Cognitive dissidence
Carol Tavris (author of Mistakes were made - but not by me) spoke at the Skeptics society on the temptation of making mistakes and depending on what is actually done, going down one of two slopes of a triangle, both diverging, but in either case justifying the route taken, especially to oneself, and generally acting later to confirm that behaviour. Several good examples including such relatively trivial matters as cheating at exams. But she did not answer coherently to the question as to what steps can be taken to rid of such cognitive dissidence. Also, a question came up as to what could be the evolutionary advantage of such behaviour. I found that question strange because not everything that survives need have an advantage for survival. Some things may happen irrespective of which path gets taken. It does not seem as if cognitive dissidence could have developed over several generations.

Another interesting point was that small non-obvious bribes could do the trick better than large ones because people feel obliged without knowing so.

Carol Tavris
Skeptics society
2007-04-26 Designer DNA
Chris Voigt from UC San Francisco spoke on: Designing Genetic Systems to Program Bacteria. He described how they can design DNA, order it commercially and get organisms to exceute their programs. Its still basic, like edge detection, and bacteria camera, but its getting better. And cheaper. Programs with several thousand DNA base pairs can now be made with the cost under 1 USD per pair. The future is here.

Interestingly, learnt today that the existence of what is called junk DNA in different species is being used by some creationist to use as an argument in their favour. I did not feel curious enough to go read that junk.

Voigt Lab
2007-04-25 Synthetic happiness
Dan Gilbert makes an interesting point about synthetic happiness vis-a-vis actual happiness, whatever that is. It seems the mind treats synthetic happiness on par with, if not superior to the other kind (which perhaps could be taken to mean the average of everyone elses happiness). that fits in quiet well with the notion that the world is a figment of ones conjuring, especially the texture above what is the background.
Dan Gilbert on synthetic happiness
2007-04-18 Encyclopedia of Life
Heard a TED talk by Edward O Wilson

The talk itself is not great, but I had heard of him earlier. He has been awarded money to make an encyclopedia of life (on the internet). He has been saying for the last 50 years how little we know about life on earth and how we mostly proceed by guesswork.

Apparently people like Stephen Jay Gould oppose his theories (I do not know what they are, but I plan to find out - have ordered a couple of books from the library). I like Gould's writing, but have always thought that they are more essay like than paper like, descriptive rather than analytical.

TED2007 talk by Edward Wilson
Biodiversity site
E O Wilson
Stephen Jay Gould archive
Stephe Jay Gould
2007-04-04 quasicrystals, Fibonacci sequence, Penrose tiles and all that
Attended a talk by Ron Lifshitz on quasicrystals, a topic I had been vaguely interested in but had left it away in some deep long-term memory corner. So all I remembered was that they were quasi crystals but did not really know much about crystals beyond their structure, diffraction patterns etc. It was interesting to learn about the relationship of Fibonacci sequence with quasi-crystals. Defining a 1d sequence with spacings (in Fourier space), one needs 2 (i.e. r > d with d=1 in this case and loosely speaking r forms the basis of a d-dimensional vector space) numbers (with irrational ratio) to cover all binary distances. Similarly in 2d, Penrose tiles with 72 and 36 degree rhombi do the job of covering the plane non-repeatatively (r=4 for d=2).

Kepler had all sorts of detailed diagrams in 1619 about what can now pass as planar structures of quasi-crystals. The rediscovery happened in 1982 when Linus Pauling wrote a paper how it can NOT be true since he was totally subscribed to crystals being necessarily periodic.

There is a third class possible when r is infinite and one has almost periodicity.

Recently Isfahan in Iran was in news for one of its 1453 mosques displaying aperoidic patterns.

Quasi-crystals
Ron Lifshitz
Linus Pauling
Fibonacci sequence
Penrose tiles
Isfahan pattern

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