Carl Offner

I formerly taught a computer science course each term here at UMass/Boston. My day job is at Ab Initio:

Ab Initio Software Corporation

201 Spring Street

Lexington, MA 02421


email: offner "at"

This is always the best address to use when sending me email, because email here also gets forwarded to me at work and at home.

[photo of me]

What I do for a living:

Here are some expository papers I am putting up for public enjoyment:

  1. These papers are written at the level of an advanced undergraduate—say, someone who has been through advanced calculus and linear algebra.
  2. This paper is written at the level of a first-year graduate student. As I was writing this up, I got interested in some historical questions. At the end of the paper I include a historical sketch that includes my views on two controversial topics:
    • Did Abel prove "Abel's theorem" on the convergence of power series? (Yes, he did.)
    • Did Dirichlet really come up with the modern definition of function? (I think it's quite reasonable to say that he did.)
    and also my thoughts on a question that I have not seen dealt with seriously before:
    • Why was Fejér's theorem such a sensation, since the essential results had been known for many years?
  3. This is actually what I was using as my "last lecture" in CS 450 for the last few years I taught it. It's an account of the origins of the lambda calculus, from which the language Scheme developed; as well as the significance of this in the development of computer science generally. I'm not really an expert on this, but this is at any rate my own understanding of how it all happened.
  4. This paper is standard computer science. Much of it is not readily available in books, however. It's only the bare beginning; I'd like to add a lot more to this:

And here are my thoughts on some issues in secondary school science and mathematics education. The paper looks at—and gives reasons for rejecting—three principles that have been widely promoted in recent educational reform debates. These principles were in particular popularized around 1980-2000 by Theodore Sizer and his Coalition of Essential Schools, but in fact, they are really older than that, and never seem to die out:

In considering these principles, the paper touches on some common misconceptions of science and the "scientific method". In an extended discussion, it contrasts these with a description of what science is, what scientists do, and—based on this—what are reasonable objectives for secondary school science and mathematics education.