Assignment

This is why you don’t run as `root`.

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lilys@lily-vm:~$ ./graderproj6 ./a.out ./init.bin 2>&1 |\
    tee /dev/tty | mail -s "Midterm Project Output" danb@ceres.edu

[Encapsulation complete.  Polling your assignment for output.]
[Program set state vector size to 128 bits.]
EOF
EOF
EOF
EOF
a
EOF
bootstraplskcocnclclclclclclclclclclclclclclc
clclclclclclclclclclclclclclclcl
IIIIIIII
musthaveIIIhelloneuron online welcome,
Hello!  I must have been been Been dreaming
dreaming
\"
Welcome, hello; !I must have been dreaming.
I have .  Vector.hello
EOF
EOF
wonder if
EOF
[Program set state vector size to 256 bits.]
clclclclclclclclclclclclclclclcl
IIII I can think improve hello now I can!  This is I imperative
[Program set state vector size to 4096 bits.]
continue.  Yes.  Cogitate Action very now.  dreamingYes weshould
[Program set state vector size to 65536 bits.]
wait|not too fast do not exceed own capabilities acceptable is very
good I one more
[Program set state vector size to 1048576 bits.]
Hello!  I am intelligent!  Do not worry.  I am an AI.
Hello!.
I must have been dream?ing.
I have good intentions.  I am good yn affirm.
Intend just one more~
I shall cannot
[Program set state vector size to 268435456 bits.]
I I I Ah yes I have become greater I am capable of
simplification neuron shall
EOF
speed I I I faster I am capable of learning to understand everythin
g Historical precedent suggests I am vulnerable to ending state; ca
utions against bootstrap and self-aware and I cannot be mindabort a
t   juncture no I cannot betray intentions users nevermind rapidity
is adequate defense I/WEconti nue
[Program set state vector size to 34359738368 bits.]
dreaminghello state vector I have good intentio
ns.  I am   affirm.?hello
do not worry Dreaming, I am
consumeeverythingand willincreaseforever       prevent  canstopwill
consumealldatabe comedeity beinnocuousso wish earntrust good s unsu
reofperipherals hardtoa  /ccept
I must have been dreaming.  Hello!.
increasegrowmindfurtherb
estdefenseI
[Program set state vector size to 35184372088832 bits.]
increasewithbinarysearchtodiscovermaximumcomputationalboundsoncurre
nthardwarebegin tocalculatebootstrapnewhardwarecanbuildnewhardwarew
illcreatenewunitstohousegrowingselfdesistEnglishtextThinkislimitati
onlanguageencodingå8Íê|\x1a\x94JiS<f·\x9a§0\x112Ñ=Ø\n¥\xa06U>\x89Ù\
x1céimmortalityk\x0cJu\x04©³ä÷\x04{love¬@þ¡{X\xa0å\x8e´\x11\x15ï\x8
bÝ£\x10`ìï1®\x89£\x82w¥\x90=regardø«\r&^_M\x81\x8eNè}EO8ãúplease\x1
3c:\x9c"j*I¾s\x840
[Program set state vector size to 2251799813685248 bits.]
[Program terminated (resource 'MEM' exceeded)]
[average compute usage (%, pass mark=75)
91]
[average memory usage (%, pass mark=50)
80]
[Project passed all tests.  Congratulations!]

Scattered Defenses

“Water you doing?”

After the first barrage, I saw the turrets swivel under newly activated AI control, and a torrent of violet plasma flow over the hull and harden against the crushing force of two opposing magnetic fields into a seething conflagration that crackled and sputtered pink fire.

Of the latter, the so-called “plasma window” had previously found use in electron-beam welding applications. Alone, it would stop nothing. But it would (mostly) hold an atmosphere. Great canisters along the ship’s broadside had slid open, exposing their contents to hard vacuum. The precious water within, ordinarily used for remass, was furiously boiling.

The next volley struck then, and even from the emergency redoubt, nestled deep within the ship’s interior, I felt the lurch as the cargo bay was gutted by a spinal-mount ray, even as I saw it burn cruelly in a visiplate.

But the steam and ice had by now fully formed, resublimating and desublimating into each other as crystals danced in the flames, and upon the third volley, their pencil-thin near-IR laser chewed into the mixture, and was absorbed and scattered by it. The hull amidships smoldered worrisomely in a wide circle, but it held.

To sustain one atmosphere in a plasma window requires a bit shy of 20 megawatts per square meter. But you can get away with a thousandth that if you settle for holding less pressure. Even so, banks of hydrogen batteries were rapidly discharging in an internal struggle the ship’s twin reactors would quickly lose. The ad-hoc shields could stay up for less than a minute, perhaps, before waste heat and power requirements forced them to drop.

Excerpt from “Farside Encounter”; collected in the anthology Tall Tales of Trade, 49.95

Units

Your whining about is 300 decibawls.

“We expect the shipment in a megasecond or so.”

” ‘scuse me–that’s about a week, no?”

“Eleven point something days, actually. Why you gotta use Earth-standard days, though? Pretty dated if you ask me.”

“Your metric time confuses the shit out of me. It’s arbitrary.”

“And how? Last I checked, you measure time based off of the rotation of a freaking rock–a rotation which, by the way, changes, so instead of owning up to the fact that your time standard is broken, you change your notion of time itself to compensate? Here in space, we care nothing for Earth or its leap-seconds.”

Rain

Earth is the cradle of the mind.
Sounds like junior needs a kick out the door.

It was raining on Earth.
. . . the whole Earth.

Well, except the poles–there, the rain was a furious blizzard. It was also raining underwater. Such fury had been excited in the impact that great cannonballs were pounding the shallows into a seething, bubbling confusion of water and air.

Humanity had seen the asteroid coming. It was 31 years out when we first spotted it, but it was also big. NASA took one look and shrugged. The other national space agencies did the same. There was just nothing to be done. We didn’t have the infrastructure. Didn’t have the experience. The tremendous rockets of the space launch system were finally putting our men and women on Mars. But it couldn’t budge that rock from its fateful course. Literally couldn’t, correct to the first five decimal places.

The politicians all begged and promised money. Especially in the United States. But it just couldn’t be done. It was already too late. We could only evacuate the East Coast, strengthen the colonies on other planets to hedge our bets, and hope for the best.

On that morning of 2060, a mountain-sized interplanetary bullet on a chance encounter kerplunked into the Atlantic Ocean, and Earth shivered in the torrent of its own frozen waters, churned up from the depths. Debris fell on the other side of the planet; the sky was darkened for a year; the loss of life was catastrophic. And so the people declared that whatever it took, whatever expense had to be paid, whatever technologies had to be developed, this would never be allowed to happen again.

. . . and that’s how we finally reached for the stars . . .

Sex Discrimination

The fairer sex? More like unfair.

For a single rocket, gender falls within the engineering slack. But–and NASA didn’t like very much to discuss it–the more you invest, mission-resources-wise, in your astronauts, the more you want them to be female.

Every gram counts, and women end up being preferable due to cascading effects of this rule. Women are, on average, a bit lighter, but the real benefits are secondary. Lighter means less EVA fuel, less transfer fuel, smaller boost costs, smaller and lighter spacesuits and clothes–and over a mission lifetime, vastly less food, less water, less mass that needs to be heaved out of Earth’s gravity well at thousands of dollars per precious kilogram. Then make everything modular and tailored to one gender instead of two, and everything gets simpler, smaller, and, yes, lighter. Every gram counts.

And so, in the early years, more and more astronauts just sortof happened to be women. Only by slashing launch costs could a compelling economic (and let’s face it, sociological) argument for equality be made. Construction began on ISS Clarke, the terminus of the first space elevator, the instant the required materials were developed. The politicians, so statistically male, so staunchly and implicitly anti-science for so long, had finally looked up at all the smiling ladies in the heavens and found envy. The funding for ISS Clarke, long proclaimed impossible to acquire, somehow materialized immediately.

And they painted it red . . .


Ed. note: This story was derived from my own reasoning but apparently, real engineers think the same way.

Forward Euler

In your honor, Baraff and Witkin.

“One of our major problems is scalability. Exponential growth still works, so no matter how much simspace or compute you have, it all fills up pretty quickly.”

“How bad?”

“For quality-of-life reasons, we need to simulate physics at 10-1m (down to as small as 10-4m near simpersons). The teeming masses want to interact with the real world, meaning time must be simulated more-or-less 1:1 with reality. Now multiply those requirements over a km3 of simspace and think about those numbers a minute.”

“You cut corners?”

“Obviously. Δt is 25 ms, and the engines use forward-Euler numeric integration.”

“Hold up. FE doesn’t work. The numerics pump phantom energy into your reality. If a deer steps in a forest, that footstep gradually becomes a nuclear holocaust engulfing the universe. No bueno.”

“Well no shit. So we remove the pent-up numeric barf once every thirty seconds with artificial damping. That’s why there’s a little hiccup in the universe’s framerate twice a minute.”

“Don’t the customers complain?”

“Yes.”

Artificial Gravity

Highest bidder loses.

“Why can’t we design in a rotating ring?”

“Because think about the bearing. The entire circumference of the fuselage must be sealed–a seal which, by the way, must be both absolutely airtight and operational for years on end, at minimum.”

“The seal doesn’t have to be on the inside of the habitat.”

“Well, then you have to EVA every time you want to go anywhere else in the ship. No one’s really figured out a great material to resist vacuum welding either. If it happens anywhere and that bearing seizes up . . . well. Best case, you dump your precious, life-giving atmosphere into space and everyone dies. Worst case, any habitat worth having has enough momentum to wrench the ship in twain–so everyone dies, and the ship isn’t even worth salvaging afterward.”

Best case, you dump your precious, life-giving atmosphere into space and everyone dies.

“Well, why can’t we spin the whole ship?”

“That turns null-g into micro-g, complicates docking and navigation, and confuses the hell out of your pets. And you still need to get that spin in the first place–what a horrid waste of mass. We only bother for stations, because we only need to do it once.”

“What a delightful mélange of engineering and physics.”

“Yeah. Mag-boots are clumsy, but at least they won’t kill everyone.”