Notes from a snowy Wednesday morning

[magid]

Such an easy commute this morning, everyone working from home or
taking the day off or something. And there wasn't enough accumulation
to be a problem, so it was pretty easy sailing. Er, driving. I'm
leaving myself the option of taking the train home if the roads are
horrible (thereby avoiding the need to find parking until after
tomorrow's clear and mid-30s makes it less difficult).

And it doesn't matter what the weather is, I see bike commuters every
day. I am not even close to that level, and I wish I were. It would
require (a) winter biking gear, and (b) different wheels, possibly a
different bike. Plus more determination. (And the showers at work to
be available again. And a pony! No, wait, if I have a pony, I
don't need another bike!)

With all sorts of space-age technology being developed all the time,
why hasn't someone developed some new pavement material, or additive
for regular pavement, that would let it move (shrink/expand) just
enough to avoid the effects of winter's freeze-melt cycles and the
resultant potholes and frost heaves and such? (Or am I just ignorant
of why this is impossible?) I never realized how truly horrible roads
are around here until I was elsewhere that doesn't have the same kind
of winter, and the roads were not just smooth, but unpatched smooth, a
glory of easy travel.

On Blagojevich: whether or not the charges against him are true (and
it doesn't look so good for him), anyone who has the chutzpah to
compare himself to Ghandi, Martin Luther King Jr., and Nelson Mandela
is a bit too egotistical for my taste, even without the whole "ignore
my impeachment and have a media circus" approach.

I should just accept that trigonometry is never going to be intuitive
for me. I can do it, but things like all the identities (double-angle,
sum and difference, etc., anything other than the Pythagorean ones,
one of which is firmly lodged in the brain, the other two derivable
from the first) just don't stick. Which is fine, since I can look them
up every time, but is a bit frustrating even so.

Is the double-napped cone used anywhere other than the brief mention
of how the four conic sections are its cross-sections?

Yesterday's announcement about the Rose Art Museum closing is
generating lots
of opposition from donors and others. No surprise. I wonder how
things will turn out.

Comments

[denimskater.livejournal.com]

You mean two single cones tip-to-tip? That's used in discussion of event cones in physics, often.

[(Anonymous)]

And a pony!

*giggle*

Driving at midday was quite slippery and uncontrolled. I don't know whether this was due to the state of the roads or there is now something wrong with my car.

[magid.livejournal.com]

Really? Cool. How does it get used? I mean, I can easily picture how a single cone would be useful, or a sphere, but the double cone isn't intuitive to me.

[magid.livejournal.com]

I hope it's not your car!

I think it makes a big difference where you were driving, with temps hovering so close to freezing.

It looks likely to freeze overnight; I think tomorrow shall be a train day.

[denimskater.livejournal.com]

The axis that goes through the center of both cones is time. At a given point, only things inside the backwards event cone could have affected that point. That point can only affect things inside the forward event cone.

The radius of the cone at any time t+delta away from time t is delta times the speed of light.

[magid.livejournal.com]

*lightbulb* I had envisioned only event and time forward.
Thank you.