Knots and Quantum Theory

Edward Witten, Charles Simonyi Professor in the School of Natural Sciences at the Institute for Advanced Study (IAS), is unusual in that he is both a first-rate mathematician and a first-rate theoretical physicist. In recent work on the surprising linkages between knot theory and quantum physics, Witten demonstrates both these capabilities as well as a third one: he is an excellent expositor both in print and in person:

When Charlie met...

Charlie Rose recently sat down and had an interesting conversation with Marc Andreessen. Key topics included: innovation, tech entrepreneurship, philanthropy and venture capital.

Letters of Note

Wonderful website.

Some examples:

• To Whom it May Inspire 
  
• Isaac Asimov
• Do Scientists pray? (Einstein)
• Steve Jobs

100 reasons to be a scientist

From the Abdus Salam International Centre for Theoretical Physics (ICTP): Not quite 100 personal accounts of the joys of scientific careers.

Of Higgs and bosons

In his essay "Physics and reality" (see endnote), Einstein observed that the fact that the world of our sense experiences is comprehensible is a miracle. By "comprehensible" Einstein meant that the inner workings of the physical world (or what he called "the world of our sense experiences") can be understood and explained by rational means (or "thinking", as he put it so simply and beautifully). Yesterday's announcement (4 July 2012) of definitive experimental evidence of the so-called Higgs boson was yet another manifestation of this most wonderful of miracles. That a few squiggles published in the pages of an otherwise obscure physics journal can possibly constitute a fundamental breakthrough in our collective understanding of the universe is astonishing. Professor Matt Strassler, a specialist in the area, explains the significance of the discovery.

Endnote:

Excerpt (p. 351) from A. Einstein, "Physics and reality", Journal of the Franklin Institute, Volume 221, Issue 3, March 1936, Pages 349-382:

The very fact that the totality of our sense experiences is such that by means of thinking (operations with concepts, and the creation and use of definite functional relations between them, and the coordination of sense experiences to these concepts) it can be put in order, this fact is one which leaves us in awe, but which we shall never understand. One may say "the eternal mystery of the world is its comprehensibility." It is one of the great realizations of Immanuel Kant that the setting up of a real external world would be senseless without this comprehensibility.

In speaking here concerning "comprehensibility," the expression is used in its most modest sense. It implies: the production of some sort of order among sense impressions, this order being produced by the creation of general concepts, relations between these concepts, and by relations between the concepts and sense experience, these relations being determined in any possible manner. It is in this sense that the world of our sense experiences is comprehensible. The fact that it is comprehensible is a miracle. 

Chinese traders in Africa

The Brenthurst Foundation has recently published a fascinating study of Chinese traders in five African countries.

The Adventures of Bilbo Baggins

Reading (to the boys):