## Happenings – 2012 Jul 21

I’m almost embarrassed to say it – in view of the terrible massacre in Aurora, Colorado – but my week was pretty good.

I returned to work, but the week off before this let me make good progress on mathematics. The next technical post will be the regression post that I was struggling with before the rings and integral domains posts went out. It’s already through stage V – out on the blog, unpublished, awaiting final edits – although I’m thinking about adding a few more pictures.

After that, I expect to put out one more regression post, and then a bibliography post for regression. And with that I’ll think I’ll stop writing about regression for a while (Yeah? Yeah!)

I’m also making good progress on the post about constructing the final tableau of a linear programming problem – without going through the row operations.

I’m also thinking about a couple of posts on electric circuits… one of which will introduce Laplace transforms… but I was also hoping to say something about how Heaviside’s operational calculus is related to Laplace transforms.

Here is the link that reminded me of it… it turns out I have 2 books that discuss the operational calculus, but neither relates it to Laplace transforms. That link, however, provided a reference… so – what else? – I slipped out to Amazon and ordered the book, Spiegel’s “Applied Differential Equations (3rd Edition)”. I’m hoping it will be a pleasant and informative read.

But I hate to order just one book, so I checked my list of potential purchases, and also ordered

Ian Stewart’s “in pursuit of the unknown: 17 equations that changed the world”…

Rotman’s “introduction to homological algebra”…

Folland’s “quantum field theory –a tourist guide for mathematicians”.

Yeah, just what I needed: another book on quantum field theory, and another book on homological algebra. And that search for books is what delayed this post until after noon.

Meanwhile, my alter ego the kid was looking at Hilbert spaces this morning… those are complete inner product spaces, possibly infinite dimensional, and are a nice intermediate stage between finite dimensional vector spaces and spaces of functions in general (“functional analysis”). They’re also essential to quantum mechanics. Maybe if the kid hadn’t been reading about Hilbert spaces I wouldn’t have ordered the quantum field theory….

Anyway, with a post almost ready to go for Monday, I am free to do whatever I want this afternoon… and I haven’t given it any thought yet today… but I’m sure I’ll think of something. (I have a list… boy, do I have a list!)

Oh, there were no earthquakes in my neighborhood during the past week.