philrm
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Commented on Suspense is the key
Not only made it work, but made it look effortless....
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Commented on Writer, Interrupted
The former. Coleridge's close friends all assumed that the story about "the person from Porlock" was just something he made up to explain why he never finished the poem; he was notorious for beginning poems and then abandoning them....
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Commented on Writer, Interrupted
And as for interruptions... might I remind y'all of Coleridge, Kublai Khan, and the Person from Porlock? Although that story is almost certainly bullshit; certainly all of Coleridge's friends thought so....
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Commented on Sad Trombone Exoplanet Reality Check
I really don't understand Hadley cells. I think the crucial question for us is why the subtropical high pressure belt is where it is, on earth. Would it be at 30° on a tidally locked planet? Fundamentally it's the result...
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Commented on From the hemline index to the vampire/zombie ratio: SF/F by the numbers
And also Jay@231: applause!...
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Commented on On the Great Filter, existential threats, and griefers
Oops! Accidentally left off: I should have been more precise, and said "the last, locally testable GR prediction, of inertial frame-dragging"....
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Commented on On the Great Filter, existential threats, and griefers
Quite true - I should have been more precise....
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Commented on On the Great Filter, existential threats, and griefers
Bingo! Newtonian physics is such an excellent approximation to special/general relativity under normal circumstances that only for very precise applications (such as GPS satellites) do the relativistic corrections need to be taken into account. It took the insanely precise Gravity...
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Commented on On the Great Filter, existential threats, and griefers
The traffic-control problem by itself is probably a superhuman task... Yeah, just the thought of the logistics involved simply in repositioning and focusing the system is enough to give me a headache. (Especially when you toss in self-gravity...) This reminds...
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Commented on On the Great Filter, existential threats, and griefers
...then dropping down after a few minutes to something more easily absorbed by the atmosphere of the target planet. Actually, you wouldn't care about this at all; the column through an Earth-like atmosphere is so large that it's opaque to...
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Commented on On the Great Filter, existential threats, and griefers
Fair point!...
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Commented on On the Great Filter, existential threats, and griefers
Well, it depends on how small: for the numbers we were quoting above, that would amount to billions of pointings per star. But of course, that would be an insane way to do it; you'd build something with a much...
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Commented on On the Great Filter, existential threats, and griefers
Also also (sorry for all the addenda, but perhaps I didn't make this clear in my original post) it isn't a question of how accurately you can determine where your target was 16.3 years ago (which is when the radio...
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Commented on On the Great Filter, existential threats, and griefers
Also, astronomers generally avoid looking in the vicinity of the Galactic Plane (the midpoint of the Galactic disk), which is where all of the planets are (because that's where the cold, dense gas that star formation occurs in is found)...
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Commented on On the Great Filter, existential threats, and griefers
True, but you can't scan the sky with one (angular resolution is spectacular --> field of view is miniscule)....
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Commented on On the Great Filter, existential threats, and griefers
I should add that I also assumed that the Earth-like planet has an Earth-like orbit (1 AU from its sun), which is where the 0.4 arcseconds per year number comes from....
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Commented on On the Great Filter, existential threats, and griefers
How long would you like it to be? Planets don't dodge! Actually, planets do dodge on the relevant timescales (the years it takes the Griefers' killing beam to arrive), which is to say, they orbit. Suppose that you've collimated your...