Getting excited about my trip, pleased to be on Holidays already though.
Unknown "Dana's Aussie" Insouciant - 16 years, 3 months, 18 days ago

In a dust solution, the only source of the gravitational field is the mass of a pressure-free perfect fluid. The bits of this fluid interact only gravitationally (zero pressure, so they don't exert any forces on each other), and their world lines are timelike geodesics). These bits of fluid are usually just called the dust particles. Their world lines form a timelike geodesic congruence. If this congruence is irrotational, there is a foliation (this term suggests the leaves of a book) by spatial hyperslices, which are three dimensional Riemannian submanifolds such that each slice is everywhere orthogonal (perpedicular) to the world lines of the dust particles. This foliation or hyperslicing provides a notion of "cosmological time", and a coordinate chart which uses this as the time coordinate is called a comoving chart.
Unknown "Dana's Aussie" Insouciant - 16 years, 6 months, 20 days ago

Alternative boondoggles

The direct cost to the US government of the war and occupation of Iraq — counting only funds appropriated by Congress — so far runs to roughly $523Bn.

However, that's the direct cost — money directly spent on the project. There are indirect costs, too: Joseph Stiglitz estimates the true cost of the war to be $3Tn to the United States, and $3Tn to the rest of the global economy. These are indirect costs, and factor in the long-term additional expenses that the war has accrued — everything from caring for brain-damaged soldiers for the next 50 years through to loss of economic productivity attributable to instabilities in the supply of oil from Iraq.

We can tap-dance around the indirect costs, but the direct costs (that headline figure of $523Bn) are inarguable.

So. What fun boondoggles could we have bought with either $523Bn (at the low end) or $6Tn (at the high end)?

NASA have plans for a manned Mars expedition based on the Ares spacecraft they're developing as a replacement for the Space Shuttle. Price estimates vary from $20Bn (presumably for a single round-trip) to $450Bn (presumably for a single round trip plus all the externalities, like developing the spacecraft and equipment and conducting a thorough prior reconnaissance using unmanned landers).

Either way, the direct costs of the Iraq war exceed the maximum cost estimate for a manned Mars expedition, infrastructure and all, by 20%. If we take $20Bn as the cost per mission and $450Bn as the cost to develop the technology to go there, the direct cost of the Iraq war would be sufficient to develop a gold-plated Mars expeditionary capability and send six crews of astronauts to Mars (and bring them back afterwards).

Going by Stiglitz's indirect estimates, the picture is even more ludicrous; for $3Tn, assuming a crew of four per expedition, $20Bn per flight, and a basic $450 start-up price, you could send 510 astronauts to Mars. That's not a Mars exploration program, that's a battalion! It's a small colony! Regular readers will be familiar with my opinion of plans to colonize Mars ... but if you throw enough money at a scheme you can probably get something out of it, even if it's only another Darien Scheme.

Or perhaps we could tackle global warming by building nuclear reactors. Westinghouse AP1000 PWRs cost roughly $2Bn a pop and have a net output of 1117Mw (1.12Gw). For $513Bn we could probably negotiate a bulk discount of, say, 20%, in which case we're good for 320 reactors, or about 375Gw of output. Our entire planetary civilization consumes about 16Tw, but the USA accounts for about 40% of that, so we could buy, outright, the equivalent of 6% of the US's energy budget. But this stuff pays for itself (it's producing electricity, a fungible commodity) and in actual fact, 50% of the USA's energy budget is coal, burned for juice. So we could cut 12% of the USA's coal-sourced carbon emissions, enabling the USA to not only meet but exceed the Kyoto protocol requirements using a single, fiendishly expensive gambit (and treating it not as capital investment but as expenditure).

For $6Tn we could buy a lot of juice — a quarter of our global civilization's energy budget would go carbon-neutral at a stroke. (Yes, we just solved our carbon dioxide emissions problem by switching to a nuclear economy.) This probably isn't the ideal way of dealing with our environmental problems, and it's a naive treatment of the costs (has anyone done a proper treatment of the economic implications of shifting the planet over to a nuclear economy, say to the same extent as France?) but it's thought-provoking.

Finally, there's all the other little stuff we could solve by pointing $513Bn at it, never mind $6000Bn. Eliminating childhood diseases in South-East Asia? Piffle — Bill and Melinda Gates are trying to do that out of their pocket lint. Build first-world grade housing in shiny new cities for 600 million Chinese peasants, nearly a tenth of the planetary population? Yes, this budget will cover that. What else?

Yes, I'm asking you: what would you do with the cost of the Iraq war (take your pick: $513Bn or $6000Bn) in your budget? Colonise Mars? Solve our carbon emission problem and fix global warming? House half a billion people? Or something else ...?

(And what isn't going to happen now, because we pissed it all away on the desert sands?)
Unknown "Dana's Aussie" Insouciant - 16 years, 6 months, 28 days ago

The Milgram Experiment (1961)

The Setup:
When the prosecution of the Nazis got underway at the Nuremberg Trials, many of the defendants' excuse seemed to revolve around the ideas of, "I'm not really a prick" and, "Hey man, I was just following orders." Yale University psychologist Stanley Milgram wanted to test willingness of subjects to obey an authority figure using an experiment where the subject was told he was a "teacher" and that his job was to give a memory test to another subject, located in another room. The whole thing was fake and the other subject was an actor.

The subject was told that whenever the other guy gave an incorrect answer, he was to press a button that would give him an electric shock. A guy in a lab coat was there to make sure he did it (again no real shock was being delivered, but the subject of course did not know this).

The subject was told that the shocks started at 45 volts and would increase with every wrong answer. Each time they pushed the button, the actor on the other end would scream and beg for the subject to stop.

So, can you guess how this went?

The Result:
Many subjects began to feel uncomfortable after a certain point, and questioned continuing the experiment. However, each time the guy in the lab coat encouraged them to continue. Most of them did, upping the voltage, delivering shock after shock while the victim screamed. Many subjects would laugh nervously, because laughter is the best medicine when pumping electrical currents through another person's body.

Eventually the actor would start banging on the wall that separated him from the subject, pleading about his heart condition. After further shocks, all sounds from victim's room would cease, indicating he was dead or unconscious. If you had to guess, what percentage of the subjects kept delivering shocks after that point?

Five percent? Ten?

Shockingly (pun intended), two thirds of the subjects (between 61 and 66 percent) continued the experiment until it reached the maximum voltage of 450, continuing to deliver shocks after the victim had been zapped into unconsciousness or the afterlife. Repeated studies have shown the same result: Subjects will mindlessly deliver pain to an innocent stranger as long as a dude in a lab coat says it's OK.

Most subjects wouldn't even begin to object until after 300-volt shocks. Zero of them asked to stop the experiment before that point (keep in mind 100 volts is enough to kill a man, in some cases).

Charles Sheridan and Richard King took this experiment one step further, but asked subjects to shock a helpless puppy for every incorrect action it made. Unlike Milgram's experiment, this shock was real. Exactly 20 out of 26 subjects went to the highest voltage.

Almost 80 percent. Think about that when you're walking around the mall: Eight out of ten of those people you see would torture the shit out of a puppy if a dude in a lab coat asked them to. If you would guess that women—commonly believed to be more nurturing than men—were more compassionate in this study, then you would guess wrong. The six students who refused to go on were all men. All thirteen women who participated in the experiment shocked the hell out of the sweet, adorable puppy right up until the end.


Unknown "Dana's Aussie" Insouciant - 16 years, 7 months, 18 days ago

The Stanford Prison Experiment (1971)

The Setup:
Psychologist Philip Zimbardo wanted to find out how captivity affects authorities and inmates in prison. Sounds innocent enough. Seriously, what could go wrong?

Zimbardo transformed the Stanford Psychology Department's basement into a mock prison. Subjects volunteered by simply responding to a newspaper ad and then passing a test proving good health and high-quality mental stability. These volunteers were all male college students who were then divided arbitrarily into 12 guards and 12 prisoners. Zimbardo himself decided that he wanted to play too, and elected himself Prison Superintendent. The simulation was planned to run for two weeks.

Yep, nothing at all can go wrong with this.

The Result:
It took about one day for every subject to go nutes. On only the second day, prisoners staged a riot in the faux detention center, with prisoners barricading their cells with their beds and taunting the guards. The guards saw this as a pretty good excuse to start squirting fire extinguishers at the insurgents. Guards began forcing inmates to sleep naked on the concrete, restricting the bathroom as a privilege (one that was often denied). They forced prisoners to do humiliating exercises and had them clean toilets with their bare hands.

Incredibly, when "prisoners" were told they had a chance at parole, and then the parole was denied, it didn't occur to them to simply ask out of the damned experiment. Remember they had absolutely no legal reason to be imprisoned, it was just a damned role-playing exercise. This fact continued to escape them as they sat naked in their own filth, with bags on their heads.

Over 50 outsiders had stopped to observe the prison, but the morality of the trial was never questioned until Zimbardo's girlfriend, Christina Maslach, strongly objected. After only six days, Zimbardo put a halt to the experiment (several of the "guards" expressed disappointment at this).

Give us absolute power over somebody and a blank check from our superiors, and Abu Ghraib-esque naked pyramids are sure to follow. Hey, if it can happen to a bunch of Vietnam-era hippie college students, it sure as hell could happen to you.


Unknown "Dana's Aussie" Insouciant - 16 years, 7 months, 18 days ago