Daily Archives: July 27, 2008

Serious Discussion

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Today’s Non-Sequitur

Quick thoughts: yes, it would fire. As Tommy Lee Jones reminds us, pistols (not just Glocks) can fire underwater, if you’re stupid enough to do so (like you’re performing DIY Shock wave lithotripsy) — they carry their own oxidant.

The bullet would travel faster, too. There would be less drag on the bullet, so it would not slow down as much as it does at one atmosphere. The muzzle velocity would only be epsilon faster, but the overall speed at some arbitrary distance would be higher.

I don’t understand why Danae doesn’t find that interesting.

(Blam! and Ping! not really happening, of course, in that rarefied atmosphere)

Update: the speed to orbit near the surface of the moon is about 1680 m/s. Not achievable with a pistol, but within the capabilities of some advanced weaponry. Escape speed (1.41 times higher) would require a Bull-like supergun.

Pick, Pick, Pick

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I spied a nit at which I must pick. This is something that’s become ingrained in certain science discussions, one of those innocent things that may or may not propagate a misconception and I’m sure it rarely causes an eyebrow to be raised, but, dammit, someone’s wrong on the internet.

Someone will tell me that energy is obtained because you’ve broken a chemical bond. It happens often enough that it’s not worth mentioning where I saw it (OK, OK, I’ll talk. It was Schwartz Matt) But seriously, it’s something you’ll run across a lot if you read stories about chemical processes and energy.

It’s one of those things that can be true but isn’t generally true. And the overall implication — that there is energy stored in the bonds which is released when you break them — is flat-out wrong.

Forming a bound state releases energy. Breaking apart that bound state requires the addition of energy. We can quantify the tightness of the bond by how much energy is involved, and that’s what we do with the enthalpy of formation: you have a baseline system — the free gases and atoms with which you start — which has (what we define as) zero energy. If you want to go from one bound system to another, you will release the difference in the enthalpies, because energy is conserved. (And if you look at more complex systems you involve the more and more complicated energies you find in thermodynamics) But the release of energy is in the formation of new, tighter bonds that are present in the products — that’s where the energy comes from. Burning those hydrocarbons is releasing energy not because you are breaking the bonds with the carbon and hydrogen, but because the bonds with the oxygen are stronger, and forming them releases the energy.

Faith and Ignorance

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Interesting link over at physics and physicists (rather than the title being a misquote from “Bull Durham.”) Is Faith The Enemy Of Science?

Richard MacKenzie of the University of Montreal has written a rather thought-provoking and lengthy article as a rebuttal to a talk given by Lawrence Krauss. In it, he is disputing Krauss’s assertion that:

Faith is not the enemy.
Ignorance is the enemy.

The linked article is pretty good.

The bottom line is that direct observation shows that faith does not obstruct scientists from
doing science. That said, there are many who portray themselves as scientists who, due to
their faith, are doing a brand of science which is an indignity to the word. I have in mind
particularly those whose principal goal in science is to advance a faith-based agenda. One
must wonder whether these individuals, who probably have a reasonable amount of scientific
talent, might not be doing respectable science if their scientificity had not been stronger, or
their religiosity weaker.

Does faith obstruct non-scientists from learning science? I would argue that it does, for
several reasons.

On that point I quite agree. Anyone who uses their ideology to dictate what answers are acceptable isn’t doing science. Ignorance isn’t the enemy, in the sense that it is an opposing entity; the goal of teaching science (and education in general) is the eradication of ignorance. Ignorance can be fixed as long as there is no active plan to preserve it. Faith, the unsubstantiated belief in something, does indeed preserve ignorance if it prevents you from considering evidence and scientific explanations.

Well worth a read.