Oh, here we are! Mr Waide's direct email address. Ben@BenWaide.com

As a non-resident of the USA, I cannot email Mr Waide. His contact page is here - note, his surname is incorrectly spelled on that page. Wa *i* de http://www.lrc.ky.gov/legislator/h010.htm

Q1: "Will I actually use calculus and above?" Who knows? Maybe you'll find that it's an enjoyable endeavour in its own right - it may not be a practically useful skill but it will enlarge and enrich your understanding of concepts that you'll not find otherwise.

Q2: " is it just a popular idea that you need to be a mathematician in order to program?" Is it a popular idea? I've certainly never encountered it. A mathematician is not someone who knows a little calculus. Modern mathematics (which, presumably, is studied by a current mathematician) is a wide-ranging and diverse field of which numerical calculus (I propose) is a rather tired and scantly addressed matter. Let's face it, most calculus that you'll probably ever meet would have been cutting-edge say, ooh, 150 years ago (Gauss' theorem of integrating over a surface... to pick an example from the top of my head)

Q3: "What are your experiences?" Programming since age 9, introduced to discrete calculus in programming in second year of Physics BSc (all in FORTRAN), 4 years writing numerical integrator-assisted tools for reusable launch vehicles, Physics MSc (no calculus), Physics PhD (trivial integrators written), postdoc (ditto), self-employed (no calculus).

But hey, why should one study something purely because you hear that it might improve your employment prospects? Do you find it satisfying and interesting? Aren't these reasons enough for studying it or is your schedule really crammed?

The simple error in the original post is trivial - it's a superconductor. And it demonstrates flux pinning. But this has been demonstrated ever since superconductors have been made with non-superconducting regions in them (ie, not elemental superconductors like Pb and Al). This is *not* news. Unless it is the mid 1980s and I've not noticed.

And the people at the company were really friendly. Colossal Adventure was a real eye-opener, and was tough enough me to grind out some oily doggeral that pleaded for help (snip: "Into colossal cavern stepped I, if only for my luck to try..."), and post it off. Look, I was only 13. A hand-written note came back within a week along with a photocopied crib-sheet, and a signed greetings card (if memory serves). When, 20+ years later, I visited Mammoth Caves, it was very strange to actually be in a place that had such resonance with my past - a real feeling (briefly) of time having no meaning and all experience being co-present. Didn't see any pirates though.

The concept predates 1996 by a good bit. (disclaimer: I used to work on Interim HoToL) HoToL, a British air-breathing SSTO, would also have used a similar engine cycle to that of the Skylon engines (aye, there are differences aplenty), and HoToL flourished as a project in the mid 1980s.