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Comment Re:Moore's Law ended years ago, for many (Score 1) 125

Depending on the specific problem, with number-crunching big databases you may be running into the limits of Amdahl's Law, not Moore's.

If part of the algorithm is inherently serial (ie, can't be parallelized), then that's going to be the bottleneck no matter how many cores you throw at it (although faster memory and I/O may help). CPU clock speed has been stuck around 2-4 GHz for many years now, throwing more transistors at the problem isn't going to help much. What we need there is not more transistors but faster ones, which means moving away from silcon to e.g. GaAs or micro vacuum tubes or whatever. One 1-THz CPU will blow away 250 4-GHz CPUs (memory bandwidth permitting) because it gets around Amdahl's Law.

Comment Re: drone ship landings require a lot less fuel? (Score 1) 101

Oh, well, if reddit users say it is so, then it must be true. [eye roll]

Argument from authority? Really?

The "east takes you up" phrasing is just a handy mnemonic for epicycles, which are a useful (in some cases) simplification of elliptical orbits (which is what a circular orbit becomes if perturbed). Fairly useless for accurate orbital modelling, or for (significantly) suborbital trajectories. (Both of which apply if you're trying to land a booster on a barge or parking lot.)

Comment Re: drone ship landings require a lot less fuel? (Score 1) 101

Oh really?

Explain highly elliptical (eg cometary) orbits then.

Orbit is a freefall where the horizontal* component of speed at apoapsis is sufficient to avoid hitting the source of gravity at or near periapsis. The first stage booster doesn't come anywhere near fast enough at its apogee.

*horizontal: i.e, perpendicular to a line drawn between the object and the center of gravity of the system.

Comment Math error someplace - twins (Score 1) 142

Since the incidence of identical (monozygotic) twins is a lot higher than that (about 3 per 1000 births)(for fraternal twins it's even higher), there's a math error someplace. Possibly in the assumptions.

The bad news for law enforcement is that not only will identical twins match on facial recognition (barring some environmentally caused disfigurement, eg scars), they'll also match on DNA evidence. (They won't, however, match on fingerprints.)

Comment To quote Gerard O'Neill... (Score 1) 306

"Is the surface of a planet really the right place for an expanding technological civilization?" -- O'Neill, 1969

Earliest source of this quote is widely claimed to be an interview by Stewart Brand in 1975. His (O'Neill's) paper on space colonization appeared in Physics Today in 1974. The original question seems to have been raised (in 1969) by O'Neill in a freshman physics course he taught at Princeton.

The students decided on the answer "no".

Comment Re:Just Stop Having the Hugos (Score 1) 702

The people in charge of them have no respect for the voting public and vice versa.

Wow, a few misconceptions to clear up here.

The people in charge of the Hugos (ignoring the SMOFs*) are the people running the particular WorldCon in the year that they're awarded. Which is to say, they're the folks responsible for running the nomination procedures, the voting, tallying the votes, etc, all within the "constitution" of WorldCon itself (which rules are, by design, NOT easy or quickly changed.) These people are in turn chosen by the "voting public" at a prior WorldCon as (part of the) con committee associated with a city competing to host the con that year. Oh, they're also responsible for the design and manufacture of that year's Awards (within certain constraints; the spaceship is a must).

This is NOTHING AT ALL like the professionally-run, for-profit cons like ComiCon. (In many ways its more fun -- no ridiculous lines, no charging for autographs or pictures, room parties and bid parties, ...)

The "voting public" comprises, for the sake of nominations, anyone who has purchased a supporting or attending membership for the con. Actual voting (which also includes voting on a couple of other awards and the location of the next worldcon) is limited to those with an attending membership (although you don't have to show up, voting is by mail/email beforehand). If you want to vote on WorldCon business matters (like changing rules), you have to show up and attend the business meeting.

(* SMOF -- Secret Master Of Fandom. It's a long-running joke.)

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