ricketyclick

Lovely graphic simulator of the effects of gravity on the universe, from simple two-body problems to colliding galaxies.
The Universe Sandbox.

[Click to enlarge. More screenshots here.]

Less than a decade ago, this was the province of room-sized supercomputers. Now available on your desktop.

I do so dearly love living in the future, although unfortunately, I haven’t been able to try this out for myself since it’s Windows-only. I have got to get around to setting up Wine or dual-boot.

Link from frequent commenter Chanda via email.

Retired engineer Steven Den Beste reprints a valuable checklist for plausible alternative energy sources:

…For too many people “alternate energy” is more about religion than about physics. They believe that if we are just creative enough, we can overcome fundamental physical limitations — and it’s not that easy.

In order for “alternate energy” to become feasible, it has to satisfy all of the following criteria:

1. It has to be huge (in terms of both energy and power)
2. It has to be reliable (not intermittent or unschedulable)
3. It has to be concentrated (not diffuse)
4. It has to be possible to utilize it efficiently
5. The capital investment and operating cost to utilize it has to be comparable to existing energy sources (per gigawatt, and per terajoule).

If it fails to satisfy any of those, then it can’t scale enough to make any difference. Solar power fails #3, and currently it also fails #5. (It also partially fails #2, but there are ways to work around that.)

The only sources of energy available to us now that satisfy all five are petroleum, coal, hydro, and nuclear.

Den Beste garnered a few good comments on that post (and quite a bit of attention elsewhere), but the best comments I’ve seen that answer some of the objections to this list are over here.

Of course, you should read Neo-Neocon’s article concerning T. Boone Pickens’ wind power project that SDB linked to, and SDB’s original detailed 2002 essay, which ought to be required reading for anyone discussing this topic.

And the 2002 essay links to SDB’s discussion of scale here:

My dad was an electrical engineer and he worked on power generation. (He spent most of his career on the hydro projects on the Columbia river.) He lived in an entirely different world than I did, a world where units like kilofarads and kilohenries were actually useful. That’s the kind of numbers you see when you’re describing long distance transmission lines. In my world, a microfarad is huge. In his world, a farad was tiny. (If you don’t know what that means, just let it pass.)

You’ve got to start thinking really, really big.

Anything which, when fully deployed, generates less than ten gigawatts average (10¹⁰ joules per second) is useless for our purposes in terms of actually making a meaningful contribution to the total amount of energy we consume.

SDB then goes on to discuss some of the more esoteric proposals for obtaining energy. It is a very depressing essay, because the scale is…bigger than most people can fit in their heads, the problems are hard, the cost is astronomical.

Steven’s preferred solution is coal, because it works and we’ve got plenty.

Still, burning carbon is stupid–it’s filthy, there is only a limited supply, it’s going to become increasingly expensive, and we need the chemical feed stock. (In my mind global warming is still very much, heh heh heh, up in the air, but I tend to discount it. We humans are simply not that significant on a planetary scale. See Copernicus and Darwin.) Simple conservation will not work for long — most of our energy systems are already extremely efficient, and “cutting back” to any significant degree would involve essentially rebuilding our society from the ground up.  Most likely, we wouldn’t like the results very much.

(Al Gore’s proposal to completely wean ourselves off carbon fuels in…am I remembering this right? Ten years? — yup, ten years, is simply stupid, particularly since I doubt nukes are even on the table in his plan.)

Everything we can do has at least a ten year lead time. First we need to open our domestic oil to drilling, including offshore and ANWR, so we can at least start to be somewhat self-sufficient. Start planning the nukes now.  There are several reasonable designs, but it will probably take at least five years to build pilot plants and choose two or three that can be standardized to reduce cost and increase competency. We also need to start pressing on fusion — not even uranium will last forever, and we don’t have good local sources, anyway. (Nearest is Canada, if I’m not mistaken.) However, fusion will involve new physics as well as fabulous engineering, and I note Steven’s response is, “Wake me when it works.”

Not that we should give up on trying make cheap solar cells and the like, but there’s a fundamental limit on how much energy comes down from the sun in a given day, and all of those solutions require an infrastructure with a huge surface area (see SDB #3).

Irena Sendler passed away at 8AM (Warsaw time) on May 12th, in Warsaw, Poland at the age of 98…. Irena was one of 180 others to be nominated for the 2007 Nobel Peace prize. In the height of irony, the award that year went to a man who has done nothing for peace, but instead threw the world into chaos and fear, while enriching his bank account - Al Gore.

Read the whole article, and honor someone who could have re-sanctified a prize that has never been washed clean of the blood from Yasser Arafat’s hands.

Originally, though, “The Cold Equations” comes from Tom Godwin’s notorious science fiction short story about orbital mechanics forcing a space craft pilot and a stowaway to make some hard choices. Wiki entry here, but beware, almost any discussion you find will necessarily involve spoilers. Let it be said that there’s some deep resonance with the current problem at hand: “Good physics, bad engineering.”

Ooh, here it is in full. It’s one of this collection of the stories that built the Golden Age of SF.

Awhile back, I quoted Brian Cox, a scientist on the Large Hadron Collider particle accelerator project, who called the idea of politicians micro-managing scientists “nonsense”.

That post garnered a somewhat rambling comment, which, if I understand it correctly, suggested that Cox had no business talking about politicians’ nonsense, since the LHC might well create a black hole that would swallow the Earth! Honest!

Taken aback at this evidence of my own rash credulity, I authorized the comment, in the hopes of giving myself the barest patina of respectable questioning of authority.

Bad Astronomy breaks the bad news: “Oh noes! We’re safe!” quoting Cox himself:

Please pay particular attention to a key point that is often missed in these “discussions”. The argument based on cosmic ray collisions is not limited only to cosmic rays impacting on the Earth, but on every astronomical body in the observable Universe, including very dense ones such as neutron stars. It is estimated that the Universe conducts of order 10^13 complete lifetime runs of the LHC every second, with no observable consequences at all. This is on top of very sound theoretical arguments that IF micro black holes can be created, then they must also decay. This statement is based not on speculative stuff like extra dimension theories, but on pretty basic quantum mechanics.

I must grudgingly admit his argument seems sound.

Nevertheless, as we all know, the facts of science, particularly Big Science, are determined not by the quality of one’s data and the rigor of one’s argument, but by the weight of popular opinion, the dictates of politicians, and, if even that does not suffice, the ponderings of our noblest and wisest exemplars, journalists.

Therefore Cox himself, having questioned the scientific acumen of, my gosh, politicians, might not be an acceptable authority. However, in this case, I’m going to have to side with him, simply because I, in my simple ignorance, can understand what he said, while Walt’s words remain almost totally opaque.

John Walker at Fourmilog (which, by the way, has one of the best mottos I’ve seen: “None dare call it reason”. That right there gets it a place on my blogroll) reviews James Dewar’s To the End of the Solar System, a history of the nuclear rocket engine program. The engineering details are daunting:

Consider: a modern civil nuclear reactor generates about a gigawatt, and is a massive structure enclosed in a huge containment building with thick radiation shielding. It operates at a temperature of around 300° C, heating pressurised water. The nuclear rocket engine, by comparison, might generate up to five gigawatts of thermal power, with a core operating around 2000° C (compared to the 1132° C melting point of its uranium fuel), in a volume comparable to a 55 gallon drum.

The payoff, however, would have been huge, up to and including the possible survival of the human race:

…What if it worked? Well, that would throw open the door to the solar system. Instead of absurd, multi-hundred-billion dollar Mars programs that land a few civil servant spacemen for footprints, photos, and a few rocks returned, you’d end up, for an ongoing budget comparable to that of today’s grotesque NASA jobs program, with colonies on the Moon and Mars working their way toward self-sufficiency, regular exploration of the outer planets and moons with mission durations of years, not decades, and the ability to permanently expand the human presence off this planet and simultaneously defend the planet and its biosphere against the kind of Really Bad Day that did in the dinosaurs (and a heck of a lot of other species nobody ever seems to mention).

Daunting those problems may have been, but they were within the grasp of the engineering gods of the time (late 50’s through early 70’s–which implies a great deal of the work was done on slide rules.)

What killed the project?
Goals were redefined, milestones changed, management shaken up and reorganised, all at the behest of politicians, yet through it all virtually every single technical goal was achieved on time and often well ahead of schedule. Indeed, when the ball finally bounced out of bounds and the 8000 person staff was laid off, dispersing forever their knowledge of the “black art” of fuel element, thermal, and neutronic design constraints for such an extreme reactor, it was not because the project was judged infeasible, but the opposite. The green eyeshade brigade considered the project too likely to succeed, and feared the funding requests for the missions which this breakthrough technological capability would enable. And so ended the possibility of human migration into the solar system for my generation. So it goes. When the rock comes down, the few transient survivors off-planet will perhaps recall their names; they are documented here.

[Bold mine.]

Read the whole, sadly enraging thing.

Now, tell me again, people: exactly why do you want these same elected gangsters and backroom thugs to run your health care?

Not, mind, that the market is perfect. Walker also details why he’s imposed the vendor death penalty on Hewlett-Packard.

For those of you who do not consider technical catalogs to be suitable bathroom and bedroom reading, here’s the skinny on the old H-P:

As a larval nerd, there were two technology companies I held in the highest esteem: Tektronix and Hewlett-Packard. Tektronix seemed to have a bit more flair: they hailed from the curiously named Beaverton in Oregon, and you’d often find something funny in the complete schematics they shipped with their oscilloscopes, such as the drive circuit for the lower gun of a dual-beam scope being replicated by a bow-legged cowboy labeled “top gun”. But H-P had real class; they printed a hardcover product catalogue, and flipping through it you found not just oscilloscopes, signal generators, and the like, but exotica like rubidium atomic clocks. Not that you were going to buy one, to be sure, but wasn’t it cool to know you could, given the budget, and that this company provided you the same specifications for the product they did to customers like the National Bureau of Standards who actually bought such gear?

Oh, yes: I’ve spent many happy hours flipping through both the H-P and the Tektronix catalogs. The Fisher Chemical catalogs are also a blast.

However, H-P, or at least their consumer division, has gone off the rails, apparently programming their printers to fail at preset times in order to force you to buy new ones, and leaving out critical parts which must be bought separately at hugely inflated prices. In this case, H-P sells you a memory module, which ought to cost less than twenty bucks, for $600, almost twice as much as the printer itself.

All’s well that ends well, though:

It’s amazing how turning one’s back upon vendors who betray you can streamline the procurement process for replacement products….

Hewlett-Packard? I turn my back on you, snuff the candle, and walk away in disgust.

Quite so, and that’s the difference between the market and the government: You can fire a bad vendor, but the government can fire a successful program–and there’s not a God. Damned. Thing. you can do about it.

Via Billy Beck.

I hate the metric system. It’s every bit as arbitrary as the Imperial system, plus it has inconvenient sizes.  Yeah, sure, a liter of water is a kilogram–but a pint of water is a pound. The Fahrenheit scale brackets normal weather between zero and a hundred. Twelve divides so conveniently in so many different ways — halves thirds fourths sixths — we have a special word for it: dozen.

And contrary to Euro propaganda, the metric system isn’t all that tailored to scientific pursuits, either. In the SI system, fundamental constants have weird, complicated units, like Planck’s Constant being equal to

instead of something reasonable, like oh, say, 2 pi.

All of this is by way of introducing the Postmetric Fables, “Stories Told in Human Scale Units”, which I ran across back in the early days of the web. These are hard little pieces, jawbreakers of the brain, but immensely rewarding of slow reading and careful thought. You can learn a lot about the way the universe works by trying to figure these out.

Here, for instance, is “Planet Hopping and Rumpus”:

In a dream, you and your friends are planet-hopping — you visit a series of small planets and whenever you arrive it always happens that the people there are celebrating their planet’s new year. For them, the new year celebration is a birthday party for the planet: the beginning of a new circle around its star. They light bonfires, put on displays of fireworks, and all go into orbit — a kind of mass helter-skelter horizontal sky-diving in all directions.

In going from planet to planet you discover that on all of them speed is measured in cents (in Earth terms about a hundredth of a mile a minute). Not only that, but they all use the same measure of force, which they call a “ton”. In Earth terms it’s about 2700 pounds,. They have a saying that if surface speed on a planet is a cent then the planet weighs tenthousand tons.

One of the first things to do upon arrival at a small planet, after checking in at the hotel, is to discover the surface orbit speed, the skimspeed — where your path curving around the planet just matches falling. Since it takes no effort, this is the speed you and everybody else will be traveling. Never exceed the skimspeed unless you wish to leave the surface, which after all is where the party is. Ten cents wouldn’t be at all unusual for skimspeed on a small planet.

Rumpus is tumult, according to Webster’s: “a disorderly agitation or milling about”. Experience shows that rumpus grows disproportionately with speed. In a milling crowd, whether of convention-delegates, dancers, bumper-cars or celebrants, if you double everyone’s speed you may get considerably more than twice the commotion. In some cases doubling the speed might increase the rumpus by as much as sixteen-fold. We can define a rumpus quantity that does increase exactly sixteen-fold when speed is doubled, simply by making rumpus the fourth power of speed. You obtain it by squaring the speed twice — a square square cent is a quartic cent.

If the skimspeed on a planet is 3 cents, then its rumpus is 81 quartic cents, which is a considerable amount of rumpus.

The local people say that a planet’s rumpus is proportional to how much it weighs. (They mean weight as measured in the planet’s own surface gravity — in other words the planet’s idea of what it would weigh.) They say that heavy planets have a big rumpus, and that for each extra quartic cent of rumpus you can count on an extra tenthousand tons of weight. If the skimspeed on a planet is 3 cents, they say, then the planet is sure to weigh 81 times tenthousand tons.

And I love the names of the units: “Skimspeed”. “Rumpus”. “Rush”. “Pony”. “Bone”.

There’s more here.

I don’t really care if you read any of this. I’m mostly making note of it so I can find it when I need a bit of mental exercise.