SandySandfort on August 29, 2009, 11:49:24 am
#1. It's science Fiction. In Science Fiction things can happen any way the author chooses. It doesn't have to make sense.
#2. It's a comic.  It's a funny book. nothing to get all excited about. It's not life changing you know. (If it is for you, seek help.)
#3. The writer and artists can do it any way they please. It's their work. It's their art. It's their idea.  Questions?  See #1, and #2.

Yes, ultimately it is our universe, but for me, if it is science fiction, not everything can happen, otherwise it is fantasy. So that means that I do not want to deviate too far from science as it is currently understood. If I am going to speculate about something that could be true, like the nature of the surface of Ceres, that is legit, though my guess is based in some knowledge of the planetoid. When I am running in advance of current technology, with things like "meat gourd" chimeras, I try to make it a scientifically valid extension of biotech. Finally, when I go completely off the hook and speculate about quantum entanglement actually being used to communicate classical information, well, while it doesn't appear to work that way, maybe scientists will discover there is a work-around.

That's me. I appreciate corrections and critiques of any bad science that is not meant to be incorrect. Those of you who just want to go along for the roller coaster are aces with me. Those who want to question--even nitpick--are encouraged to do so, up to a point. The purpose of EFT is to entertain and if along the way it makes you think, that is gravy.

Daavik on August 31, 2009, 05:31:52 pm
So if I'm figuring this right assuming the radius of "the little prince" is 5km that means a surface area around 314 sq km.  30 (10%) for fresh water, 180 (57%) for salt water, and only ~104 km left for living on.  That's a nice size for a small population but it still seems that the salt water area is larger than really needed especially if you need room for homes, research facilities, land recreation areas, farming, etc.

SandySandfort on August 31, 2009, 08:42:28 pm
So if I'm figuring this right assuming the radius of "the little prince" is 5km that means a surface area around 314 sq km.  30 (10%) for fresh water, 180 (57%) for salt water, and only ~104 km left for living on.  That's a nice size for a small population but it still seems that the salt water area is larger than really needed especially if you need room for homes, research facilities, land recreation areas, farming, etc.

TLP is more of an estate than a world. The population will never be very large. Tobi likes sailing so there is an "ocean." The islands will be seeded with wildlife (including some surprises). With some minor exceptions there will be no farming beyond hydroponics, aeroponics and personal gardens.

(BTW, just to complicate matters, the strip's TLP is different from the original short story's TLP. Short story TLP is 6.133 in diameter instead of 5.133.)   :P

Sean Roach on November 12, 2009, 06:45:25 am
Must be a fluke then.

MacFall on July 16, 2010, 09:08:10 am
I was thinking of ripping off borrowing the Little Prince concept for a story I'm writing (giving credit of course), with a few modifications. I posted the idea on a forum for sci-fi fans and asked any physicists in the house to critique it (I'm no scientist myself, and I don't plan on writing strictly "hard" science fiction but I also don't want to make any really stupid mistakes).

Anyway, the physicists seem to think that even a microscopic black hole would compress a planetoid the size of the Little Prince into the size of a golf ball fairly quickly. I.e., using an historical time scale rather than an astronomic one.

I don't know how much research you've done on this - more than me, I'm sure - but there seems to be a consensus to the effect that it wouldn't work very well. Which sucks for me, because now I'm back to O'Neill Cylinders and those aren't nearly as badass as mini-planets with black holes in.
Government is not, as is often believed, a "necessary evil". Rather, it is a plain evil of such power that it has been able to convince people of its necessity.

J Thomas on July 16, 2010, 09:36:57 am

TLP is more of an estate than a world. The population will never be very large. Tobi likes sailing so there is an "ocean." The islands will be seeded with wildlife (including some surprises). With some minor exceptions there will be no farming beyond hydroponics, aeroponics and personal gardens.

Unless he's willing to move a lot of salt, he'll find himself with the amount that's in the rocks he uses. If they don't have much then he'll have a fresh water ocean which is not so bad. If they have excess then he'll need to get rid of some of it or else accept a dead sea with at best brine shrimp.

He could easily wind up with too much arsenic, too much of various heavy metals, too much or too little phosphate, etc etc etc. Our oceans have equilibrated through a very long process that involves water sucked deep and heated and sent back with different minerals, biological processes removing stuff, etc. It might be hard to duplicate. Something you could spend centuries tinkering with. So in the short run it might make sense to arrange to get fresh water some places, and accept that you'll have a wastewater ocean that comes out however it comes out, and you can pay somebody to spend the rest of his life figuring out how to improve it.

SandySandfort on July 16, 2010, 05:53:47 pm
I was thinking of ripping off borrowing the Little Prince concept for a story I'm writing... Anyway, the physicists seem to think that even a microscopic black hole would compress a planetoid the size of the Little Prince into the size of a golf ball fairly quickly. I.e., using an historical time scale rather than an astronomic one.

The Little Prince is already compressed. Did they actually read the strip or did they just the description from you? Remember on the patio when Tobi was explaining TLP? The black hole is vanishingly small. Yes, it has a lot of gravitational attraction, but if you run the numbers, you will see that at the surface it is attenuated to less than a g. So not much up there is going to be compressed. In that conversation, Tobi explained that near the black hole, the planetoid material was compressed into neutronium and that above that, it was compressed into degenerate matter, but as you climb away from the black hole, you find normal (though highly compressed) matter, until on the surface it's less compressed than on earth. Anyway, that's how I see it.

SandySandfort on July 16, 2010, 06:00:01 pm
Unless [Tobi is] willing to move a lot of salt, he'll find himself with the amount that's in the rocks he uses. If they don't have much then he'll have a fresh water ocean which is not so bad. If they have excess then he'll need to get rid of some of it or else accept a dead sea with at best brine shrimp.

He could easily wind up with too much arsenic, too much of various heavy metals, too much or too little phosphate, etc etc etc. Our oceans have equilibrated through a very long process that involves water sucked deep and heated and sent back with different minerals, biological processes removing stuff, etc. It might be hard to duplicate. Something you could spend centuries tinkering with. So in the short run it might make sense to arrange to get fresh water some places, and accept that you'll have a wastewater ocean that comes out however it comes out, and you can pay somebody to spend the rest of his life figuring out how to improve it.

Possibly true, but that's the pool boy's problem. Nanites, reverse osmosis filters, biotech (arsenic sequestering algae?), etc., can condition the water. Plus with life extension a reality, Tobi can afford to be patient. (Unless they shoot him, of course.)  :-\

MacFall on July 16, 2010, 07:03:05 pm
I don't know if they read the comic or not. I did link to it.

Anyway, it won't work for my story because the planetoids are being built rather than found like the LP was. Making a black hole can be explained with believable sci-fi tech; just inventing enough matter to make planets with Earth-like gravity within the solar system cannot. They might as well just be building Earth-size planets out of asteroids and comets and Saturn's rings.
« Last Edit: July 17, 2010, 11:25:23 am by MacFall »
Government is not, as is often believed, a "necessary evil". Rather, it is a plain evil of such power that it has been able to convince people of its necessity.

wdg3rd on July 17, 2010, 01:04:18 am
I was thinking of ripping off borrowing the Little Prince concept for a story I'm writing... Anyway, the physicists seem to think that even a microscopic black hole would compress a planetoid the size of the Little Prince into the size of a golf ball fairly quickly. I.e., using an historical time scale rather than an astronomic one.

The Little Prince is already compressed. Did they actually read the strip or did they just the description from you? Remember on the patio when Tobi was explaining TLP? The black hole is vanishingly small. Yes, it has a lot of gravitational attraction, but if you run the numbers, you will see that at the surface it is attenuated to less than a g. So not much up there is going to be compressed. In that conversation, Tobi explained that near the black hole, the planetoid material was compressed into neutronium and that above that, it was compressed into degenerate matter, but as you climb away from the black hole, you find normal (though highly compressed) matter, until on the surface it's less compressed than on earth. Anyway, that's how I see it.

Most folks got no idea how the inverse-square principle applies to gravity and other stuff.  They think if you're twice as far from the radio station, just crank up the volume twice as loud.  Shocks them when they move from an area where "classic rock" has control into a region where "traditional country" (or Hip-Hop) has that frequency.  I'd blame public education, except I went through public education (but learned to read first).
Ward Griffiths        wdg3rd@aol.com

Men will never be free until the last king is strangled with the entrails of the last priest.  --  Denis Diderot

J Thomas on July 17, 2010, 08:38:20 am
The Little Prince is alreadyThe black hole is vanishingly small. Yes, it has a lot of gravitational attraction, but if you run the numbers, you will see that at the surface it is attenuated to less than a g. So not much up there is going to be compressed. In that conversation, Tobi explained that near the black hole, the planetoid material was compressed into neutronium and that above that, it was compressed into degenerate matter, but as you climb away from the black hole, you find normal (though highly compressed) matter, until on the surface it's less compressed than on earth.

I can imagine a problem with the neutronium falling into the black hole. The faster it falls in the bigger the black hole gets and the faster more neutronium falls in, so that there could be serious problems in historical time. I haven't done the math. The math would depend on assumptions that I can't tell are true.

I don't think this is a gotcha. We currently don't know how to make or find a microscopic black hole and the last I heard nobody knew for sure whether it's possible. We don't know how to pack neutronium around a microscopic black hole in historical time. Etc. So stabilising a black hole at the center of the neutronium (perhaps in some sort of bubble that the neutronium stays out of) is just one more thing that could be discovered in coming centuries.

SandySandfort on July 17, 2010, 10:23:37 am
I can imagine a problem with the neutronium falling into the black hole. The faster it falls in the bigger the black hole gets and the faster more neutronium falls in, so that there could be serious problems in historical time. I haven't done the math. The math would depend on assumptions that I can't tell are true.

Our hypothetical black hole is 50 nanometers in diameter. A neutron is about one femtometer in diameter or about 1/50,000,000th of the black hole. So the temptation is to believe the black hole can eat all the neutrons very quickly. However, three factors mitigate against this.

1. The number of neutrons that can fall into a 50 nanometer hole over a given time period is still exceedingly small. The percentage change in the mass of the black hole is going to increase only very slowly even if the the neutrons could just tumble straight into it, but they can't.

2. The neutrons do not fall in a straight line. They are caught up in a rapidly spinning accretion disk that resist falling into the black hole with centrifugal force. This is much as why a soap bubble takes so long to go down the whirl pool as the shower water drains.

3. Plus massive amounts of energy in the form of x-rays and other photons are blasted out of the black hole as the accretion ring spirals inward. This causes an enormous pressure outward, which retards the neutrons as they drop into the black hole.

This all goes to tell me that if a naked micro-singularity captured a planetoid, it would take a very, very long time to eat it.

ZeissIkon on July 17, 2010, 01:59:55 pm
Escape velocity for TLP is a bit under 900 kilometers per hour. If TLP had no atmosphere, our bad guy would hit at some high percentage of that speed. Because there is an atmosphere, however, he would accelerate during his fall until he reached a terminal velocity of about 200 kph. Why? Because TLP's atmospheric density is approximately that of Earth's, and about 200 kph is the fastest a person can fall through that much atmosphere, irrespective of the strength of the gravity field.

Terminal velocity is a (fairly) simple relationship between air density, aerodynamic drag coefficient of the falling body, and gravity (local to the current altitude); it defines the falling rate at which aerodynamic drag equals the force of gravity.  On Earth, where gravity is effectively the same value from surface to the upper edge of the sensible atmosphere (close to the 100 km international boundary of "space"), this figure varies from over 1000 km/hr at the edge of space (where "sensible" atmosphere means you can get usable reaction against a body moving at near orbital speed) to under 200 km/hr just above the surface.  On another body with the same surface atmospheric density as Earth, terminal velocity would scale with roughly the square root of gravity (because drag scales with the square of velocity); if you have 60% gravity, your terminal velocity would be roughly 85% of the Earth surface figure -- call it 170 km/hr, or not quite twice the "double nickel" speed limit I grew up with.  Not survivable unless you land in something that slows your fall gradually.

There are recorded cases people who have survived terminal velocity falls due to falling on something that slows them gradually, rather than almost instantly like the ground or the surface of water (at 100+ km/hr vertical fall, you may as well hit concrete).  One of the best documented was a WWII gunner from a B17 who fell 20,000 feet (around 6 km) without even a streaming parachute (he couldn't wear the 'chute in the belly turret, so didn't have it with him when the turret was blow out of the aircraft), but landed on top of a tall spruce, stripping branches down one side of the trunk to the ground (and thus stopping in twenty meters or so instead of a few tens of centimeters).  On the other hand, the number of cases of this kind of survival run to around a dozen in the century or so since humans have had the ability to fly high enough to hit terminal velocity in a fall (I don't count skydivers who land with a collapsed parachute, since the streamer still significantly reduces their falling rate).

J Thomas on July 19, 2010, 02:16:40 am
I haven't done the math. The math would depend on assumptions that I can't tell are true.

Our hypothetical black hole is 50 nanometers in diameter. A neutron is about one femtometer in diameter or about 1/50,000,000th of the black hole. So the temptation is to believe the black hole can eat all the neutrons very quickly. However, three factors mitigate against this.

I find your reasoning somewhat plausible but not convincing. The pressure at the center of a big glob of neutronium....

But it isn't  important enough to me to do the math. And I'd be disappointed if you did the math when you could be telling a great story instead. I think my handwaving is adequate -- in the time between now and then there could be advances in physics that would show people how to get the effect you want.

I like it that you've thought out a plausible background that might allow the result you want. I'm sure it was fun and it adds depth to the story. Please don't let us science trolls get you arguing beyond the point it stays fun.

 

anything