Jason Underdown’s Blog

This book is a beautifully illustrated gem! It examines Euler’s famous formula: V-E+F=2 which holds for all polyhedra or surfaces which are topologically equivalent to the sphere. The formula is an example of a topological invariant, something which can be computed for any surface, and thus allows one to categorize surfaces. The book also covers the famous classification theorem which categorizes all surfaces as either homeomorphic (topologically equivalent) to a sphere, n-handled torus, or sphere with n cross-caps (projective plane). Next it dives into knot theory and Seifert surfaces, before moving on to the interplay between topology and geometry, and ends by mentioning homology and how topology is done in higher dimensions.

I found this book in the library the other day and found it to be a very good introduction to the basics of particle physics. I liked the fact that it explains the basics of the experimental side of particle physics as well as introducing the three families of leptons and quarks. Too often, popular science books explain the various subatomic particles with out giving you any idea of how we actually know of their existence. Because of this, I think disbelief tends to creep in. But Close does an excellent job of explaining the basics of how accelerators operate and also the basics of how detectors work. And he does all this in only 129 pages! Very short indeed, and highly recommended.

I did an REU (Research Experience for Undergraduates) this summer and we used the textbook “Ideals, Varieties, and Algorithms” (isbn 978-0-387-35650-1) by David Cox, John Little, and Donal O’Shea. As the title mentions, algorithms are an important tool in the study of varieties via their corresponding algebraic ideals. One of the main tools used in algebraic geometry is what is known as a Groebner basis, which is somewhat akin to a basis set in Linear Algebra. Anyway, I wrote some C++ code which implements a few of the algorithms in the book, but stops short of implementing Buchberger’s algorithm for computing a Groebner basis. The code should be useful as a starting point because it implements a Monomial class and a Polynomial class both with lots of useful methods thus eliminating the drudgery of implementing the book’s algorithms in C++.

The code can be found at: my web site as a gzipped tarball. Please let me know if you find it useful. I developed the code on an Ubuntu Linux machine, but it is generic enough that it should compile on any platform. You will need to read the README to understand the simple input, output format.

While googling for information on the Virial Theorem, I ran across a really cool page hosted at the Harvard ADS system. ADS stands for Astrophysics Data System, and it is primarily an abstract search engine that helps you locate journal articles mostly in the realm of Astronomy and Astrophysics, but they also have a small virtual library of books that you can freely download.

Here are the titles I found interesting:

• The Foundations of Celestial Mechanics by George W. Collins, II
  (1989, 2004).
• The Fundamentals of Stellar Astrophysics, by George W. Collins, II
  (1989, 2003).
• Fundamental Numerical Methods and Data Analysis by George W. Collins, II
  (1990, 2003).
• The Virial Theorem in Stellar Astrophysics, by George W. Collins, II
  (1978, Pachart Publishing House, Tuscon, Arizona).

If you want to concatenate all the separate PDF chapters, I recommend using the texexec method oulined in this web page by Matthew Skala.

This book is Lee Smolin’s attempt to diagnose the physics community. Smolin entered graduate school in 1976, at the end of arguably the most fruitful era ever known to physics. However, since the 1980s no new fundamental challenges to the canon of physical theory have succeeded in reshaping how we view our universe. Although this fact troubles and frustrates Smolin, it is not this lack of substantial progress that he cites as the problem with physics. The problem as he sees it is that the majority of theoretical physicists are barking up the wrong tree, namely string theory. He argues very convincingly that string theory fails as a unifying theory. In the introduction he cites Nobel laureate Gerard ‘t Hooft as saying,

“I would not even be prepared to call string theory a ‘theory,’ rather a ‘model,’ or not even that: just a hunch. After all, a theory should come with instructions on how to deal with it to identify the things one wishes to describe, in our case the elementary particles, and one should, at least in principle, be able to formulate the rules for calculating the properties of these particles, and how to make new predictions from them. Imagine that I give you a chair, while explaining that the legs are still missing, and that the seat, back and armrest will perhaps be delivered soon. Whatever I did give you, can I still call it a chair?”

Smolin sees the widespread adoption of string theory as a continuation of the “shut up and calculate” mentality of the particle physics era that was so successful. He also argues that this follow the leader attitude is hurting diversity, especially the young physicists with bold new ideas. Not becoming part of an established research group and striking out on one’s own research path is tantamount to career suicide in theoretical physics, at least for those without established reputations. The notable exception of course is Einstein, but people like him are rare.

He divides his argument into four parts. In the first section, he sets the stage by giving a brief overview of the five great problems in theoretical physics, and the early attempts at unification. I especially liked how he described his set of heuristics for judging the promise of a new theory.

In the second section he gives a whirlwind history of string theory up to current times. This part of the book will be difficult for someone not familiar with the jargon of string theory. I recommend reading Brian Green’s “The Elegant Universe” before tackling this book, as it is a good introduction to string theory.

The third section examines some alternatives such as Smolin’s own research in loop quantum gravity as well as other programs such as Alain Conne’s non-commutative geometry research.

The final section looks at the physics community from a sociological perspective, attempting to understand how its internal power structure strongly encourages certain behaviors and punishes others. As a soon-to-be graduate student, I found this section to be very informative.

I strongly recommend this book. I however admit, that with only a bachelor of science degree in physics, I’m not yet qualified to judge string theory let alone even the Standard Model, but I can say that the book is well-written and I found it very interesting.

I found this book in my local library and read it over the weekend. It is a quick read, but has some excellent advice. One thing I liked is the advice on how to read a math text or other technical material. The main idea is that if you get stuck, don’t go backwards assuming you missed something, instead keep going because often you’ll find the new or unfamiliar term defined in a short while. I only learned this myself about a year or two ago. It definitely seems counter-intuitive to keep going, but in the long run it usually works.