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Comment Try "Sexy" not "Slutty" (Score 1) 267

Since you apparently like them to wear the costumes, you'd probably be better off describing them as "sexy" rather than "slutty". Would you tell a woman, "That outfit looks great! I love it when you dress up like a dirty $2 whore." ?

The thing is saying they're slutty suggests disapproval of the behavior (and probably of female sexuality in general); it's an insult (though it can be taken in good fun sometimes, like any insult). I assume you don't actually feel this way, so then choose a different word that better communicates how you do feel.

Personally, I don't think there's anything wrong with female sexuality; in point of fact, I rather enjoy it.

Comment Range of Engagement and Entertainment (Score 1) 121

They did the usual movie./TV sci-fi thing of having all the ships, including the big capital ships, engage at ranges of a few hundred metres, instead of a few million miles. And no real explanation of why they didn't just nuke each other with guided missiles instead of shooting more or less conventional guns at each other.

Well, clearly the short answer to why they didn't nuke each other at long distance is that it wouldn't make very interesting television. As far as I recall, BSG didn't really discuss what factors determined the tactics of space battles. If you played the game Mass Effect, I was impressed by how much detail was in the codex about space battles and how the physics and practical considerations shaped the tactics.

In that case they have FTL travel and "kinetic barriers" (i.e. shields), but they state that most engagements would occur at thousands or millions of kilometers, since the main weapons are large rail runs that fire slugs of material at very high speeds (e.g. 0.1 c) as a kinetic weapon. Then it's just a question of the speed at which a ship can fire slugs versus the speed at which it can dodge its opponents' slugs. They do, however, outline certain tactical situations where ships may be forced to engage at close range (e.g. defending a planet). The ships have very effective laser-based missile defence systems, so guided missiles are only useful in a large barrage that can overwhelm the system. They also make the very astute point that dissipating heat (generated by engines, defence, and weapons systems) may actually be one of the biggest problems in a space battle and limit the length of engagements.

Of course, when you finally see space battles in that game (and the following ones) they appear more-or-less as in your typical space opera. My impression was that they threw out all the good sci-fi they'd written about earlier because it would make for uninteresting battles, although now that I think of it they may have fit them all into those tactical exceptions.

Comment Re:Tug of War (Score 2) 207

I would think that in most cases a "serious sport" is totally pointless. Most of the sports serve no purpose other than enjoyment (of the competitors and/or spectators). Some sports may involve skills transferable to more practical endeavours, fighting or generally tasks involving endurance, but even then the scope of their practical usefulness seems pretty limited.

Personally, I enjoy watching beach volley ball occasionally. I find that volleyball is more interesting and dramatic when there are only a few players on each side. I don't know how important the beach aspect is, though it certainly adds some difficulties and makes dives a more frequent occurrence.

Comment APS Study Found These Systems Lacking (Score 4, Interesting) 302

I remember that the American Physical Society (the professional organization of physicists) studied various boost-phase missile defense schemes years ago. They found that the various options, including air-borne lasers, weren't likely to be very useful in realistic scenarios (even under otherwise optimistic assumptions).

The press release says:

The Airborne Laser currently in development has the potential to intercept liquid-propellant ICBMs, but its range would be limited and it would therefore be vulnerable to counterattack. The Airborne Laser would not be able to disable solid-propellant ICBMs at ranges useful for defending the United States.

Few of the components exist for deploying an effective boost-phase defense against liquid-propellant ICBMs and some essential components would take at least 10 years to develop, said Study Group co-chair Daniel Kleppner. According to U.S. intelligence estimates, North Korea and Iran could develop or acquire solid-propellant ICBMs within the next 10 to 15 years. Consequently, a boost-phase defense effective only against liquid-propellant ICBMs would risk being obsolete when deployed.

You can also read the full report. I don't know how the relative states of the technologies stand today.

Comment Re:Sigh (Score 1) 206

I agree that ultimately what is the oldest living thing comes down to a question of semantics. A distinction that's often made is clonal versus non-clonal organisms. I've seen Methuselah called the oldest non-clonal organism. The creosote bush that you mention is a clonal organism, as is Pando, a clonal colony of aspen thought to be something like 80,000 years old.

Comment Re:600 light years... (Score 1) 257

Remember, though, that the mass itself is not really the important part. The question is what is the surface gravity. Using your assumption of identical density (maybe not likely, but I don't know offhand what density is likely), the mass of this new planet in terms of the density rho will be M = rho*4/3*pi*R^3. The gravitational acceleration at the surface will be
a = (G M) / R^2
Combining that with the expression for the mass gives
a = G*rho*4/3*pi*R^3 / R^2 = (G*rho*4/3*pi) R.

All the stuff inside the parenthesis is assumed to be the same for both planets, so if we want to write it in terms of the surface gravity of Earth, g, and radius of Earth, r, then we'd have
a = g*(R/r). Thus, the surface gravity (under the assumption of identical density) is only 2.4 times greater.

Of course, if you're going to visit this place and plan to leave again (maybe not so useful without warp drive, given) then you might also be concerned with the energetic depth of the gravity well. For an object of mass m to escape to interstellar space from the surface will require an amount of energy
E = G*M*m/R
and in terms of the earth value E_earth this would be
E = (E_earth)*(R/r)^2
meaning it will take about 6 times as much energy as getting off Earth.

I was actually just thinking about this issue the other day while playing Mass Effect, because I was wondering if they'd done their numbers right on the planet properties (they had).


Submission + - John McCarthy, AI Pioneer, Dead at 84 (

mpearrow writes: Wired has an article about the death of John McCarthy, the inventor of the LISP programming language and possibly the single most important contributor to the field of AI.

Submission + - Lisp Creator John McCarth dead at 84 (

johnjaydk writes: The creator of Lisp and arguably the father of modern artificial intelligence, John McCarthy, died last night.

Lisp was (and to some extend still is) a radical leap forward and have had a strong influence on a lot of other languages although many still refuse to see beauty between parens.


Submission + - John McCarthy, creator of Lisp, has died (

mikejuk writes: John McCarthy, the man who, among other things, first coined the term "Artificial Intelligence" and who invented the Lisp programming language died, aged 84, on October 23, 2011. The first use of the term "Artificial Intelligence" came in John McCarthy's proposal for a two-month, ten-man workshop to be carried out at Dartmouth College in 1956. This event went ahead, with Marvin Minsky, Claude Shannon, Nathaniel Rochester, Arthur Samuel, Allen Newell, Herbert Simon, Trenchard More, Ray Solomonoff and Oliver Selfridge, and is considered as "the birth" of AI.
McCarthy went on to create LISP. motivated by his
"desire for an algebraic list processing language for artificial intelligence work",
Best known as a way to torment students with brackets it is still considered to be the language of AI and it has influenced languages as different as JavaScript and Clojure.

Comment Re:Not the same thing (Score 1) 771

My girlfriend and I both read and liked the comic, and we were both pretty happy with the movie. We went with a couple of friends who had not read the comic but actually were the ones who suggested seeing the movie. They really did not like it. From talking to them, the problem seemed to basically be one of unfulfilled expectations. They knew it was a movie about superheroes and were expecting a typical superhero movie, which is to say an action-packed movie with pretty light themes. What they got was something that was dark and more dialog and ennui than action, so they were not happy.

Maybe if they'd been expecting something different going in they would have liked it better or perhaps not. Maybe there were other people who it would have suited better, but they decided not to see it assuming it was just another dumb superhero movie. I don't know, but I wouldn't discount the effect of mistaken expectations.

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