Lucy in the Sky ...

We are already back in Nassau, but a few days ago we saw something rare during a whale watching tour in Tromsø: stratospheric clouds (supposedly of type 2, i.e. water/ice clouds).
They are quite easy to recognize due to their rainbow colors, which brings me to this question: Why are clouds in the stratosphere so colorful but the usual clouds in the troposphere just black and white?
I think I have an answer, but I would prefer to hear an opinion from readers first ...

global group therapy

You are probably already aware that Scott Aaronson wrote a comment to his blog post about Walter Lewin which got a lot of attention on twitter and the internet in general.
Now we know why his blog is called shtetl-optimized and I think we understand better some of his earlier blog posts about biting vaginas and rape (meanwhile he deleted this blog post #260).

I find his story (which included his wish to be chemically castrated) quite disturbing and the environment he grew up in must have been very unhealthy.
His confessional triggered not only criticism from professional feminists but all kinds of comments, including similar confessionals from other young men and also women; overall the whole debate is among the weirdest ones I have ever seen in our global shtetl.
Wow. Just wow.

Blog Archive