### I YELL BECAUSE I CARE

(if i now recall correctly).

(i think i’ve finally *now*
got my schedule for the
quarter… two linear analyses,
two analysis-twos, and a
discrete… into synch with
my life-itself schedule [so
that i’ll usually know things
like who i’m typing to, about
what class, and why. all i
need is some regular sleep
to start remembering things).

the “ALL CAPS” MEANS YOU SHOULD
TAKE OFFENSE convention is a dumb
thing that happened; one should ignore
it when not typing for the internet.

if it’s the way i’m most comfortable doing it,
well it’s *my* handwriting and probably more
legible than that of most of my readers at that.

and if a student thinks that the language
“abuse of notation” means i think they’re
doing something very wrong? they’re not
wrong about *that*. if they think *i’m* being
“abusive” in using what you and i both know
to be a common turn of the phrase in math
departments? they’re flat-out wrong.

alas, the upshot of all this. i’ll be commenting
less, probably a lot less. so much the worse
for the students who might’ve found my
(well-informed, thoughtful) remarks useful.
so much the worse for my ideal of having
done anything but serve as a rubberstamp
for chump change. one should know better.

if we don’t let BS artists get away with murder
in these classes, there won’t *be* any class…
and they know it. “harsh” might’ve motivated
a small few actually to take something seriously
that would otherwise have done some other
thing (like scratch out a copy of somebody
else’s work, worse than the original, because
this whole thing is just a silly little ritual anyway;
there’s a lot of that [for example; i *don’t* say…
because i don’t know… anything about the
particular student with the “abusive” remark]).

nothing a grader… or a lecturer… can do
will change the nature of large-enrollment
“weeder” courses. and i’ll’ve been some-
what naive to think of ours as any other
kind of course just because the book
is actually written well (modulo the hints).

ah, well. getting back to work. one
more thing.

i’ll quit the job laughing before i try
to change my handwriting around to
suit the whims of some silly beginner.

1. http://en.wikipedia.org/wiki/Cauchy_product

just now *one* student (out of eleven)
mentioned this (and only a handful
appear even to have tried using it)
in showing from the
(limit-of-taylor-polynomials)
definiton of exp that
exp(x+y)=exp(x)exp(y).

so that paper got “outstanding”
written on it and i looked up the
w’edia entry i’ve just cited.

alas, the same student tried in
the next problem to treat $\infty$
as if it were a number (and got
“this is not analysis” written there).

the best of times, the worst of times…

2. The Levi-Civita symbol is related to the Kronecker delta. In three dimensions, the relationship is given by the following equations (vertical lines denote the determinant):[4]

\begin{align}
\varepsilon_{ijk}\varepsilon_{lmn} & = \begin{vmatrix}
\delta_{il} & \delta_{im}& \delta_{in}\\
\delta_{jl} & \delta_{jm}& \delta_{jn}\\
\delta_{kl} & \delta_{km}& \delta_{kn}\\
\end{vmatrix}\\
& = \delta_{il}\left( \delta_{jm}\delta_{kn} – \delta_{jn}\delta_{km}\right) – \delta_{im}\left( \delta_{jl}\delta_{kn} – \delta_{jn}\delta_{kl} \right) + \delta_{in} \left( \delta_{jl}\delta_{km} – \delta_{jm}\delta_{kl} \right).
\end{align}
A special case of this result is (4):

\sum_{i=1}^3 \varepsilon_{ijk}\varepsilon_{imn} = \delta_{jm}\delta_{kn} – \delta_{jn}\delta_{km}
sometimes called the “contracted epsilon identity”.

(w’edia… now on their fund drive, btw).

$\sum_{i=1}^3 \varepsilon_{ijk}\varepsilon_{imn} = \delta_{jm}\delta_{kn} - \delta_{jn}\delta_{km}$

3. Click to access 2cultures.pdf

sitting in an armchair trying to understand graphs… gowers

4. ingenious people exist,
especially in hungary.

5. http://www.maths.ed.ac.uk/~tl/a/
tom leinster on AMS & NSA… in HTML

6. vlorbik

The issue, once again, is that I was not cut out to be a nurse, and academia is like nursing: you tend to impaired patients and you are patient with the delusional, and you serve, and serve, and serve.

https://profacero.wordpress.com/2014/12/31/the-snake-oil-standard/

coldhearted scientist tells my life story. again.

• ## (Partial) Contents Page

Vlorbik On Math Ed ('07—'09)
(a good place to start!)