Advogato blog for amatus

Yet another thing #google is doing to make my life as a #ejabberd operator unpleasant. I can't talk...

Tue, 5 Mar 2013 20:14:15 GMT

Yet another thing #google is doing to make my life as a #ejabberd operator unpleasant. I can't talk to any new gtalk users because I can't send presence subscription requests to them!

[Operators] Spammy invites

Quadrocopter Pole Acrobatics

Fri, 22 Feb 2013 05:10:31 GMT

And I thought I knew how to write correct shell scripts.

Thu, 21 Feb 2013 20:10:10 GMT

And I thought I knew how to write correct shell scripts.

Rich’s sh (POSIX shell) tricks
This page is meant as a repository for useful tricks I've found (and some I've perhaps invented) for scripting the POSIX shell (with some attention to portability to non-conformant shells as well, sca...

#wtfgoogle #its2013 #turnonencryption

Thu, 21 Feb 2013 04:09:53 GMT

#wtfgoogle #its2013 #turnonencryption

[Operators] Gmail federation

A couple articles on experimental and theoretical progress on topological insulators. These might be ...

Sat, 2 Feb 2013 12:12:19 GMT

A couple articles on experimental and theoretical progress on topological insulators. These might be among the new physical phenomena that have the greatest potential for useful applications, and are another manifestation of the beautiful interplay between topology and electromagnetism.

Some great physical explanations can be found in this 2-year-old Physics World article:

Unlike superconductors and magnets, which have order associated with a broken symmetry, topologically ordered states are distinguished by a kind of knotting of the quantum states of the electrons. This topological order “protects” the surface states, so that they cannot be eliminated by disorder or chemical passivation, and it endows them with special properties that may be useful for applications ranging from spintronics to quantum computation.
http://www.physics.upenn.edu/~kane/pubs/p69.pdf

Found via this newer article recounting some of the key steps, including the recent awarding of the 2013 Physics Frontiers Prize to three pioneers of the field:

What applications these new generations of topological materials might have is probably beyond our current imagination. That being said, there is recent experimental evidence that a 1D topological superconductor can support Majorana bound states, which may be the building blocks of a fault-tolerant quantum computer. This work was in fact Science Magazine’s runner-up for the 2012 scientific breakthrough of the year, trailing only the discovery of the Higgs boson. Let’s hope this is the start of a trend!
http://quantumfrontiers.com/2013/01/12/topological-insulator-trio-recognized-by-2013-physics-frontiers-prize/

#scienceeveryday +ScienceSunday

Unqualified Reservations: How Bitcoin dies

Thu, 24 Jan 2013 17:09:11 GMT

Unqualified Reservations: How Bitcoin dies
TL:DR - Bitcoin dies in two very simple steps. 1: A DOJ indictment is unsealed which names everyone on Planet Three who operates, or has ever operated, or perhaps who has ever even breathed on, a BTC/...

I'm still waiting for the awesome language that will finally kill C.

Thu, 10 Jan 2013 18:16:24 GMT

I'm still waiting for the awesome language that will finally kill C.

Damien Katz: The Unreasonable Effectiveness of C
The Unreasonable Effectiveness of C. For years I've tried my damnedest to get away from C. Too simple, too many details to manage, too old and crufty, too low level. I've had intense and torrid love a...

A solution to the 12 coins problem: 1 L-- 2 LL- 3 LR- 4 L-L 5 R-L 6 RRR 7 RLR 8 RLL 9 --R 10 L 11 -RR...

Thu, 6 Dec 2012 08:12:25 GMT

A solution to the 12 coins problem:
1 L--
2 LL-
3 LR-
4 L-L
5 R-L
6 RRR
7 RLR
8 RLL
9 --R
10 L
11 -RR
12 -RL
#cleaningscrapsofpaperoffmydesk

If you have a unit interval and you want to know how many ways you can divide it such that division marks...

Thu, 6 Dec 2012 08:12:25 GMT

If you have a unit interval and you want to know how many ways you can divide it such that division marks are at m/2^n and the divisions are sorted from smallest to largest, use this recurrence relation:
a[0] = 1
a[n] = 1 + sum_{i=0}^{n-1} {2^(i(n-i-1))a[i]}
#cleaningscrapsofpaperoffmydesk

If you have an n by m grid of points, you can connect 4 points to make a square in (2mn^3-2mn-2n^4+n^...

Thu, 6 Dec 2012 08:12:25 GMT

If you have an n by m grid of points, you can connect 4 points to make a square in (2mn^3-2mn-2n^4+n^2)/12 different ways.
#cleaningscrapsofpaperoffmydesk