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> this is exactly the idea of the "ringworld". Larry Niven wrote
> about twenty novells or so around a fictive world like this.
I forget whether "twenty" in this case means three or four.
--
Anton Sherwood, http://www.ogre.nu/
"How'd ya like to climb this high *without* no mountain?" --Porky Pine
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David El Tom wrote:
> . . . . But even Larry Niven had to introduce some sort of
> hyperdense material so that this small hull want fly apart.
Hyperstrong, not hyperdense; making it heavier only adds to the problem.
--
Anton Sherwood, http://www.ogre.nu/
"How'd ya like to climb this high *without* no mountain?" --Porky Pine
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Mike Williams wrote:
> Where does your hollow asteroid get its light from?
Perhaps the other end is glass.
--
Anton Sherwood, http://www.ogre.nu/
"How'd ya like to climb this high *without* no mountain?" --Porky Pine
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> "Larry Hudson" a escrit
>> No, it's not a resonnance. The way I've heard the two tides
>> explained is that the ocean is raised by the moon's gravity on that
>> side of the earth, but it also pulls the _earth_ away from the
>> water on the far side. So the high tide on the far side is not
>> that the water is higher, but that the earth is lower.
Marc Jacquier wrote:
> A kind of (squared) gradient of gravity?
Why squared?
--
Anton Sherwood, http://www.ogre.nu/
"How'd ya like to climb this high *without* no mountain?" --Porky Pine
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> Larry Hudson wrote:
>> No, it's not a resonnance. The way I've heard the two tides explained
>> is that the ocean is raised by the moon's gravity on that side of the
>> earth, but it also pulls the _earth_ away from the water on the far side.
Darren New wrote:
> Um, not really.
I don't see why not.
> Tides are caused when any large body orbits a point. Consider two rocks
> on the moon, one on the ground very close to the Earth, one on the
> ground on the side we never see. [snip orbital mechanics]
This does not contradict Larry's version.
> It hasn't anything to do with pulling the centers of planets towards
> or away from anything. It has to do with the fact that from outside
> a system, gravity can be calculated as a point source, but inside
> a system you have to account for distances.
So if the Moon were a point mass Earth would not experience tides?
Bzzt, try again.
Newton showed that a spherically symmetric body - i.e. one whose density
varies only with radius - produces the same g-field (outside its
surface) as a point mass. I guess what you mean by this "inside a
system" jazz is that the g-field of a less regular body, or group of
bodies, can be considered spherically symmetric from far enough away but
not up close. (I wonder how far away a space-probe gets before its
navigation can safely treat the Earth-Moon system as a single body.)
--
Anton Sherwood, http://www.ogre.nu/
"How'd ya like to climb this high *without* no mountain?" --Porky Pine
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Wasn't it Anton Sherwood who wrote:
>
>And I'll bet Dyson qualified the conjecture with some such phrase as "in
>the limit", i.e. he doesn't expect perfectly complete capture, but the
>amount of light captured gets ever more complete over time.
Perhaps he's expecting the inhabitants to have a biological imperative
to reproduce without limit, so that their population tends to rise
exponentially. If the practical limit to the population of a star system
is the amount of energy they can capture from the star, then there'd be
strenuous efforts to capture the energy that leaks through the last few
gaps.
--
Mike Williams
Gentleman of Leisure
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Wasn't it Anton Sherwood who wrote:
>> this is exactly the idea of the "ringworld". Larry Niven wrote
>> about twenty novells or so around a fictive world like this.
>
>I forget whether "twenty" in this case means three or four.
The four main ones are "Ringworld", "Ringworld Engineers", "The
Ringworld Throne" and "Ringworld's Children", but many other Niven
"known space" books portray a universe where the existence of the
Ringworld has some slight effect (even if only in hindsight). In
particular "Crashlander", "Protector" and several of the Man-Kzin wars
series.
--
Mike Williams
Gentleman of Leisure
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Anton Sherwood schrieb:
>> this is exactly the idea of the "ringworld". Larry Niven wrote
>> about twenty novells or so around a fictive world like this.
>
>
> I forget whether "twenty" in this case means three or four.
>
yepp, .. , I Know what you mean, but in opposite to D. Admas with his
five-part trilogy's or so, Niven was quiet productive. With a quick look
at my bookshelf I see at least 7 novells dealing directly with ringworld
("ringworld epos"), at least 5 playing in the same universe ("kzin
wars") and 12 more books spawning other universers and following other
strange SciFi ideas. And these are only the ones I can call my own.
So roughly 10000 pages of brain washing lyrics for little boys ;-)
By the way, ..., a world Niven spawned a story around was a solar-system
without planets at all. Just a torus shaped dense rotating atmosphere
around a sun. Live developed in form of and on integral shaped trees.
Seas and oceans where just blobs of water drifting in the cloud.
... dave
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"Mike Andrews" <nomail@nomail> schreef in bericht
news:web.434fc6b84ff5b998c717c9af0@news.povray.org...
>
> For practicality I prefer Banks' 'Culture' ring model which is to have a
> smaller ring orbiting in a star's life zone, spinning once per day to give
> one g of centripetal accelleration and with a small rotation plane offset
> from the sun. If I got my calculation right (a = lw^2) the radius is about
> 1.85 million km, which still gives a huge surface area for a reasonable
> ring width - and you can build several in one system :-)
>
> (Wanders off, dreaming of how to reduce Jupiter to workable material ...)
>
And there you get the Ringworld described by Larry Niven!!
Thomas
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Jim Henderson schrieb:
> On Fri, 14 Oct 2005 22:01:07 +0200, David El Tom wrote:
>
>
>>But even Larry Niven (AFAIK a physician writing
>>SciFi)
>
>
> Larry Niven holds a BA in Mathematics and a minor in Psychology.
>
> http://en.wikipedia.org/wiki/Larry_Niven
>
> Jim
Anton Sherwood schrieb:
> David El Tom wrote:
>
>> . . . . But even Larry Niven had to introduce some sort of
>> hyperdense material so that this small hull want fly apart.
>
>
> Hyperstrong, not hyperdense; making it heavier only adds to the problem.
>
thanks both for correction, it's now at least 10 years that last read
these books, but's not a good appology, I know ;-)
Wright now I hardly find the time to read novells, instead I have to
read API documentations and program references in my spare time ;-)
... dave
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