Was Reading: Symmetry

I never finished writing this blog piece on a book I was reading, but the pieces are coherent enough to push out….

Sautoy, Marcus Du. Symmetry: A Journey into the Patterns of Nature. Harper, 2008.

Fun stuff so far. One big revelation has been the parallel between simple groups and prime numbers. I’m still a bit unclear on the concepts — so I will struggle to explain them properly and clearly.

Classification of finite simple groups – Wikipedia, the free encyclopedia:

The classification of the finite simple groups, also called the enormous theorem, is believed to classify all finite simple groups. These groups can be seen as the basic building blocks of all finite groups, in much the same way as the prime numbers are the basic building blocks of the natural numbers. The Jordan-Hölder theorem is a more precise way of stating this fact about finite groups.

List of finite simple groups lists the 26 simple finite groups, including the famous Monster group.

Reading the book has made me look at the bathroom tiles, to notice that all the tiles are of one type — and that you just need to rotate them.  What symmetry group is embodied by the tiles?  Is the vast majority of commerical household tiles of the same group?

When did people start making tiles?

What is quasi-periodicity?

How does symmetry show up in textiles? I’m working through understanding List of planar symmetry groups – Wikipedia, the free encyclopedia

Reading about Sabbaticals

I’ve long been intrigued by what a sabbatical affords you in terms of opening up a way of making big changes in your life. Not surprisingly, you can find some books on personal sabbaticals to get guidance on how to structure a sabbatical (You can also get a sabbatical coach (e.g., Coaching Services) but you should be able to get a lot out of reading a book and spend $600/month!). Some interesting looking books on the topic include:

Figuring out some basic investing advice: use value investing?

I’ve had two investment books out from the public library on my bookshelf for several weeks: The little book of common sense investing : the only way to guarantee your fair share of market returns and The little book of common sense investing : the only way to guarantee your fair share of market returns and am finally getting a bit of time to look at them. I’ve had a fair amount of my retirement money invested in a S&P 500 index fund — so I’m familiar with the notion of investing in an index fund. As Laura and I consider investing in BRK.B – Berkshire Hathaway Inc., Laura and I learning about Value investing, particularly its relationship to Warren Buffett, which is described in the following terms:

    However, the future distributions and the appropriate discount rate can only be assumptions. Warren Buffett has taken the value investing concept even further as his thinking has evolved to where for the last 25 years or so his focus has been on “finding an outstanding company at a sensible price” rather than generic companies at a bargain price.

I’m still trying to understand how to apply concepts such as P/E ratio to assess how good a buy Berkshire Hathaway is. Should I believe what Berkshire Hathaway Intrinsivaluator says?

Social life around books

In posts to come, I will write about books that are currently on my mind and my reading list. But first: a bit about the process of discussing books on the web.

Over the last couple of years, I’ve used various websites that let you record books that you own or read and what you think of those books: LibraryThing, goodreads, Visual Bookshelf (a Facebook application), and Shelfari This selection of sites doesn’t even include my Amazon wishlist (“Stuff I find interesting”), a WorldCat “Stuff I find interesting” list, my Google Books “My Library“, and other lists I must have forgotten about. Some of these lists I use actively, while joining (in response to a friend’s request) has been the only activity I’ve performed.

I’ve been intrigued by book-oriented social network services for some time now, but none of them has won me over. I explained my reluctance to adopt these services on p. 238 of my mashup book:

One thing that keeps me from investing too heavily in these sites is the struggle of how to move my book data in and out of any of these sites. For any given site, I look for APIs that help in that regard as well as any feeds that might allow users to easily import and export data.

In other words, I’d like to use any website of choice and have my information show up on all of them. I’d even be willing to program such information exchange (that’s where the APIs come in.)

When I write about books, I have a choice about where to write — on this blog or on one of the book social network services, or in a traditional print publication (among others). I will try to write in a lot of places and see what happens.