What Good Is Math?

From Kiery King, who was deprived of a basic education, the reason why they need math:

http://www.kieryking.com/2016/01/on-math-programming/

and how being denied an education based on sex is still very much alive and well in the United States of America:

http://www.kieryking.com/2014/02/in-which-my-genitals-mean-i-dont-learn-math-or-science/

If you know someone who wants to do (math, science, sewing, whatever) don't tell them they can't because they are (female, black, male, whatever).  Don't stand there and let that person's parents tell them they don't need to/are not allowed to learn.  Deliberately sabotaging someone else's choices because of arbitrary and nonsensical gender restrictions is a vile thing to do.

No Food Weekend

A good friend of mine is a teacher in a low income area.  Not only does she teach kids, a feat I find remarkable, this weekend she is going without food just so that she can understand her kids better. She will be discussing the experience here.

Caturday Post: Scaramouche In a Large Box With Paper

In Which Conan the Engineer Takes a Nap

The story thus far.

After cleaving in twain the coffee-belching toad, Conan sank to the ground, his mighty thews at the last weary from his travails.  Stretching out his taut and muscular frame, glistening with sweat, upon the sward next to the tarn of coffee spewed by the monstrous toad which he had just hewn in twain, Conan sank into slumber.

While he lay there, like a panther on a high branch, ready to become alert at the slightest disturbance, he dreamt.  In his mighty warrior's dream he found himself in an ancient and massy datacenter.  Even the smallest of universal serial bus cables had the girth of Conan's great arm, and the power cables were large enough to crush a man in their coils even as a great boa constrictor crushes a cayman. 

Greatly wondering, yet undaunted ,for nothing of heaven above nor hell beneath could daunt the mighty engineer, Conan approached the server nearest him, leaving light sandal prints in the untracked dust.  With the fearless resolve of a follower of the great god of the Cimmerians, Cron, he ascended 99 steps to a great platform upon which rested a keyboard and monitor, and entered a keystroke.  Immediately the monitor screen filled with these dread characters, repeated over and over:

"ERROR:  requested WAL segment 00000001000051E200000053 has already been removed"

Then Conan awoke, disquieted. 

Caturday Post: Castle

Tamerlane sits in the house portion of the new cat tower.

Do I Really Have To Find The Conveniently Lying Around Puzzle Hint?: Basic Combinatorics and Computer Games

Screen text: I don't know the right combination, and trying to find it will take too long.

Situation 1: combination lock.  3 buttons (levers? thingamajigs?) , each button has 5 sides.  Without any further information to rule out possible combinations, I have 5 choices for the first button, 5 choices for the second button, and 5 choices for the third button, for 5*5*5 = 125 total possibilities to try for a brute force test-everything solution.  Assume I need 2 seconds to set each button to a possibility.  Then the maximum time I need to test a combination is 6 seconds (less for combinations where I need to change only one or two slots).  6 seconds * 125 tries = 750 seconds or 12.5 minutes.  Assume I stop for a break and to make notes to keep track of my attempts.  I can still reasonably force the lock in under 30 minutes.  Even in a real-time game, unless you are in a down-to-the-minute crunch, this is doable.  Tedious (very tedious!), but straightforward.  I don't truly need someone's conveniently left out password here. 

How about this one?

Screen text: I can't figure this out without a plan.

Situation 2: A clearly magical harp sitting in a swamp (if it weren't magical, we would have serious water damage to this poor instrument).  We do have a limited number of pitches: 17, one for each colored segment.  (My mouse pointer is covering up one such segment). If we assume the magical melody is

• exactly 17 notes long, no repeats, we have 17 choices for the first note, then 16 choices for the second note, 15 choices for the third note, etc., for 17*16*15*14*...*3*2*1 = 17! = 355687428096000 combinations.  Way too many to test without a computer!  (Read the "!" as "factorial" in this context.)
• exactly 17 notes long, repeats allowed, we have  17*17*17*...*17 = 17^17 = 827240261886336764177 possible choices.  Way too many to test!  (With a computer?  I'm not sure.  Let me do some more research.)
• Less than or more than 17 notes? Less than, and you could probably still force it with a computer eventually.  Small enough and you could do it by hand.  More than 17?  Well, how much more?  At some point you can always make the problem too big.  Even the integers are infinite.  (And the real numbers are infinitely more infinite than the integers.  In a mathematically well-defined and amazingly mind-blowing way.)
• If timing and tempo matter?  Forget it.  

I do need a conveniently lying around hint for this one, even with an untimed game.

Edit: turned out situation 2 was just about tuning the strings, rather than a combination.  Since tuning is an aesthetic choice (individual or cultural), yes, I did need a guide. 

Australia's First 4 Billion Years

For light watching with lovely glimpses of geology and computer generated scenes of ancient life, I highly recommend Australia's First 4 Billion Years.   It's a NOVA documentary, but you can find it on Youtube, just search the title.

I think the best part is the "driving" into the past at 60 million years per hour: all of humanity occupies only the first 2 seconds of the journey, while it takes over 3 days to get to the beginnings of Earth.  It's a nice way to try to make the vastness of time more immediate and conceivable. 

My favorite parts are the CG scenes of trilobites and their world.  I find trilobites pleasingly symmetric and streamlined:

Order: Ptychopariida
Suborder: Ptychopariina
Superfamily: Ptychoparioidea
Family: Marjumiidae
Species: Modocia typicalis
Source: Trilobites.com