I think I remember it starting in 1984, actually. In 1989 they published a book, imagining that they were at about the half-way point to completion, talking about their approach. I followed it with some enthusiasm at the time, hoping it would go somewhere, but beyond a few modest surprises it never went too far. One interesting thing was that at one point, it asked its programmers whether or not it was a human being, or maybe deduced that it wasn't, I forget which.
It also looks like you're trying to state power per unit distance using units of area, not distance.
My point was that "power per unit distance" doesn't make any sense. Watts per mile is physically meaningless. Watts per square mile is non-standard but at least it's the right dimensional analysis. Antenna gain and 4*pi are both dimensionless, so I didn't bother with them. I was just looking for something proportional to radiated power, not necessarily equal to it.
Another responder used square miles per watt, which rewards good performance with bigger numbers, not smaller. With hindsight, that's the thing I would prefer to change with my original posting.
Height does matter, my point was that for VHF and above, it's basically line-of-sight. (Not exclusively, I once got ducting on 2 meters between Maine and Massachusetts.) Line-of-sight goes farther if you're on a tall tower. Assuming WLS goes 1000 miles (that's what I think of as the "radius" of the midwest), they're getting about 0.175 watts/sq.mile. Better than typical thanks to their tall antenna, but not that much better. I live in New England where we have a lot of hills and valleys, so it's unusual to get a really long run. The commercial stations here seem to prefer locations where they're not blanketing huge areas.
"BFE" = base flood elevation? That's the best I could figure with Google, and I'm still not sure what it means.
The units here are watts per square mile. Your typical FM radio station has a range of maybe 50 miles and is running maybe 10 kwatts, so they're doing 4 watts per square mile. This guy is doing much better. My own power/distance record, back when I was active in ham radio, was 7000 miles on about 25 watts, or 5.10204082 × 10**-7 watts per square mile.
You might wonder how it's remotely possible for there to be a gap of seven to ten orders of magnitude. Why aren't we bothered by FM radio stations on the other side of the world? There is a qualitative difference between the behavior of radio waves above and below about 30-50 MHz (the FM band starts at 88 MHz). Conditions permitting, the lower frequencies can refract in the ionosphere and come back down to earth along non-straight-line paths. That's why shortwave radio stations on other continents can be heard.
This is a great idea. There is a risk that breaking off chunks carelessly might make the whole mass slide. So there'd have to be some study and planning before we started.
It might also be possible to ease tectonic pressures under the Canaries by making some artificial volcanoes, or making some cuts in plates to give a little more elbow room, assuming those are practical things to try to do. This would push off the problem farther into the future.
But then if big projects like those are practical, maybe it'd be practical to set up some baffles in the water around the Canaries to break up the tsunami, and intentionally trigger it at a known time.
I can see why this is an interesting question: How intelligent would the thing causing the collapse have to be to be considered an observer? I have often wondered why quantum mechanics seems to assign a special role to an "intelligent" or "conscious" observer. I thought it was supposed to be the case that consciousness, while poorly understood, is nothing more than a particular pattern of nerve firings.
A little later you say that it becomes fixed when an action happens from which an observer can deduce the state in question, but this still seems to assign a special role to an intelligent observer. I thought from your earlier question that you were trying to get away from that. Or does deducibility-of-state coincide with some other condition to which an intelligent observer is irrelevant?
Asimov (and others) proposed that they didn't use ``junior'', so the first Methuselah named his son Methuselah, who named his son Methuselah, and so on for 900+ years.
That's an interesting idea. But I'm inclined to doubt that the tradition would last 900 years; somebody in that time would develop an independent ego and give himself a new name. Maybe people in those days couldn't really count all the way to 900, and therefore use the number the way 5-year-olds equate 100 with infinity. Or maybe using over-large numbers was an accepted form of exaggeration (the fish was THIS BIG).
I don't think the Bible is intended to be specific and factual and accurate, like comic books or cartoons or porn. It's story-telling. Enjoy it as such. Remember the words of Jack Handy: We tend to scoff at the beliefs of the ancients. But we can't scoff at them personally, to their faces, and this is what annoys me.
I just want to make sure I still get print access to the Internet. Did anybody notice if George mentioned a subscription rate? And will it come with coupons in the back for eBay and Amazon stuff?
Google has to pay the bills too. Their approach to advertising has been pretty damn palatable compared to many alternatives out there. You and I don't have the power to force them to include a !shopping flag, but what would happen if we could?
There would be no ad revenue for Google because nobody would ever look at an ad. That would mean either they go out of business, or it would mean more draconian feature reductions or other wierdness to try to compensate for the loss of revenue.
The ads along the right side aren't annoying. There are things to worry about (like no more date range searching) but the ads aren't it.
One of the huge problems for normal highways is the merging that
occurs near on-ramps. If there are supposed to be idle cars at each
station, there each station needs a short length of sidetrack where
the waiting cars are queued up.
I didn't see this in the few pictures I looked at. It seems like such
an obvious thing they must have thought of it. But in addition to the
sidetrack, you need a merging algorithm for cars re-entering the main
track. Not necessarily rocket science, but something they'll need to
think about, and maybe think pretty hard if they are so fortunate as
to get much volume.
China as a state is far more concerned about being able to control its people effectively than it is about outside powers.
Maybe China's disinterest in other parts of the world was simply because it lacked the resources to cheaply watch other parts of the world. These satellites will be in low orbits. They'll get to look at every point on the Earth. Once they're up, the Chinese need only watch the feeds for "interesting" things.
The power base of the Chinese government has been slowly eroding, due largely to the influx of investments from the West. Surveillance is power, both inside and outside the country. This is probably an attempt to increase their power, at the expense of Chinese citizens (and the rest of the world).
Apollo 8... couldn't accelerate all the way from here to halfway to Alpha Centauri. You'd get there a lot faster on ion drive.
To maintain the acceleration, you need sunlight hitting the solar panels. When you get that far out, the sunlight's going to be very weak. By then you might have picked up plenty of speed (I haven't done the math) but at the halfway point you won't have the acceleration you had near the inner planets.
Laugh about this if you want, but phishing emails have a much higher success rate than ordinary spam. There are people getting hurt by this. Maybe everyone you care about is Internet-literate, but I care about lots of people who aren't.
I'm older than most Slashdot readers. I'm still young enough and mentally alert enough to recognize when something is screwy. The first time I got a 419 email, I could see there was something obviously wrong. Fast-forward a very small number of decades. I'm retired, I'm out of the loop, I've probably lost a few IQ points, and I'm on a fixed income. I might not be clever enough to recognize the next scam. I might get taken to the cleaners.
Speaking as somebody a little closer to the end of his life than many here are, I find this kind of stuff very worrisome.
Why is a machine that washes your dishes an "appliance" while a machine that mows your lawn is a "robot"? Where is the line drawn?
At the institute they LAUGED when I insisted on building a lawnmower with broadband connectivity and an IQ of 285 and a Simmering Rage circuit. But who's laughing NOW, that they're mass produced and used worldwide? Boy, I sure hope they don't ever get the idea of uniting to rise up and overthrow the humans. But I don't think they'll ever stumble across ideas like that on the Internet, so I guess we're OK for now.
The quoted article continues: An Orwellian world is much easier to recognize, and to oppose, than a Huxleyan... We take arms...buttressed by the spirit of Milton, Bacon, Voltaire, Goethe and Jefferson. But what if there are no cries of anguish to be heard? Who is prepared to take arms against a sea of amusements? To whom do we complain, and when, and in what tone of voice, when serious discourse dissolves into giggles? What is the antidote to a culture's being drained by laughter?
If one puts aside the trivial, there is a grimness to life. There is unhappiness, poverty, social unfairness, illness, and death. Every now and then somebody cures a specific disease (though less and less in recent decades) but the great mass of dissatisfaction remains essentially unchanged. Social issues are very rarely addressed successfully.
Anybody who puts down his distractions will be faced with that reality. We mostly can't stand that experience so we pick up our distractions again. When people notice that stuff and talk about it, we tell them to stop being a bummer.
New distractions are required frequently so we don't have time to remember we're distracting ourselves, and we just think it's how life really is. This makes the vendors of distractions wealthy. It's big business.
I once went to a great dharma talk by a teacher from Hawaii. He talked about another teacher in Thailand whose great innovation was to bring dissatisfaction out of the closet -- people normally try to avoid talking about it, turn it into a taboo, say that talking about is wimpy and whiney. This guy brought it out into the light and encouraged his students to look at it from every angle, and grapple with their reactions to it.
I won't say I went home and followed that advice. Trying that would have at least been interesting, and at best might have made me a much happier person in the long run. But it was an interesting talk. If I ever go to Hawaii, I hope to find that guy again.
I'm starting to be convinced about the pinwheel. For a first approximation, I assumed that (a) the arms reach all the way to the ground, and (b) the weight of the ship is negligible compared to the center weight of the pinwheel. One of the big constraints is, as the arm is reaching its lowest point and you're trying to grab it, there's a tradeoff between how much vertical displacement you can handle and how quickly you can grab the arm. I assumed 100 feet of displacement, and after some tinkering came up with a capture window of about three seconds. The numbers:
800 miles length of pinwheel arms
13422.3 MPHs ground speed of pinwheel
2.9529 seconds to grab the cable
11.2347 minutes riding the pinwheel
8.96209 MPSs speed when leaving the pinwheel
5 pinwheel rotations til next try
112.347 minutes til next try
231.425 miles to next try
If you miss the 2-second capture window, you can wait for the next try. As previously noted, the pinwheel requires as many landings as launches to avoid orbit decay.
I don't think that catching ships headed for the surface is your answer. In both the cases of launching and catching, you are loosing orbital height to gravity.
I think you may be incorrectly envisioning how the catching would work. If you're standing under the perigee point, the rock is going overhead in a horizontal direction (from left to right, for sake of argument), and the problem to be solved is that its horizontal velocity isn't as much as you'd like, so the orbit won't take it as high as you want.
As the rock is going by, there is a ship coming in from Mars, quickly overtaking the rock from the left. The rock shoots out a rope and the ship catches it. Now the ship races ahead of the rock and drags it rightwards. The ship wants to slow down so it can land, the rock wants to speed up, so this is a win-win situation. Then the rock starts reeling in the rope to slow the ship down even more (and also speed itself up more).
Eventually the ship is going slow enough so it lets go of the rope, and glides gently down into the atmosphere, and the rock's orbit is pumped back up to where it was before the previous ship launched.
Here's my understanding with the space elevator. The most serious proponent these days is a guy named Bradley Edwards who came out of one of the national labs. His idea involves beaming power up to the climber from the ground:
The power for the construction and cargo climbers (100kW to 2.4 MW) is beamed up using a free-electron laser (840 nm) and 13 m diameter segmented dish with adaptive optics, identical to the one being constructed by Compower Inc. and received by GaAs photocells (80% overall efficiency at this wavelength) on the climber's underside. This power, converted to electricity, would be used by conventional, niobium-magnet DC electric motors and a set of rollers to pull the climbers up the ribbon at speeds up to 200 km/hr.
He makes a case that you don't want the climber to carry its own fuel. Anyway, GEO is 35800 km up, so if you're going 200 km/hour, it takes 7.45 days to get there.
How much thrust would it take to put the rock back into its original orbit? Would it be less fuel than to just to push the passenger in the first place, accounting for drag on the cable? Could this be offset by being able to use an ion jet on the rock instead of chemical rockets on the passenger?
I showed this idea to a co-worker and he raised this point: if the passenger is delivering fuel to the rock, the energy content of that fuel would have to be exactly the same as it would have taken the passenger to get into orbit by himself. Conservation of energy and all that.
There's still a winning situation, though, which is where instead of pumping the orbit with fuel deliveries, you pump it by catching returning spaceships and decelerating them. As long as the rock collects as much momentum landing ships as it spends launching them, this is a workable system.
Maybe when the rock is near apogee it could throw out a solar sail, but I think the energy it would get per orbit doing that would be negligible compared to the energy cost of launching a ship. So catching ships is probably the winning idea.
Pull the slag together into 10 ton pellets, slowly move them with solar sails and assemble an artificial asteroid in earth orbit out of the waste material from the mining operation.
That sounds like a good approach. It probably makes sense to start out with a metal skeleton in the desired orbit, with lots of places onto which chunks of asteroid can be duct-taped as they become available.
One way to pump up the orbit is to bring in and attach new asteroidal chunks when the framework is at apogee, and moving relatively slowly, and the chunk is coming in from far away and probably moving a good deal faster. This assumes we're good shooting cables at things and attaching them, but we need that skill anyway to use the thing for launches.
I haven't yet thought through the process of using momentum from returning ships to pump up the orbit, but if the rest of this idea is feasible, presumably that would be as well.
It would take quite a bit of work to figure out the physics behind it
I've gotten curious enough about this stuff that I've started learning a little bit about orbital mechanics. I've written some Python code to do the calculations for this stuff. Here's the asteroid's orbit:
o = Orbit(rmin, vmin) for v in [ o.perigee, o.apogee ]: - # Slashdot's ecode tag does not preserve leading whitespace! - print v - print (v[0] - earthRadius) / mile, "miles" - print (v[0] - earthRadius) / km, "km"
This needs my libraries for
physical units and
orbits,
and produces these results:
(<6.69997e+06 m>, <10000 m sec^-1>) 200.0 miles 321.8688 km (<3.52573e+07 m>, <1900.31 m sec^-1>) 17944.7223304 miles 28879.2312141 km
Slashdot Mirror
I think I remember it starting in 1984, actually. In 1989 they published a book, imagining that they were at about the half-way point to completion, talking about their approach. I followed it with some enthusiasm at the time, hoping it would go somewhere, but beyond a few modest surprises it never went too far. One interesting thing was that at one point, it asked its programmers whether or not it was a human being, or maybe deduced that it wasn't, I forget which.
Here is the USPTO listing for this thing. HP (and a few other groups) have been working on this kind of stuff for a long time.
My point was that "power per unit distance" doesn't make any sense. Watts per mile is physically meaningless. Watts per square mile is non-standard but at least it's the right dimensional analysis. Antenna gain and 4*pi are both dimensionless, so I didn't bother with them. I was just looking for something proportional to radiated power, not necessarily equal to it.
Another responder used square miles per watt, which rewards good performance with bigger numbers, not smaller. With hindsight, that's the thing I would prefer to change with my original posting.
"BFE" = base flood elevation? That's the best I could figure with Google, and I'm still not sure what it means.
The units here are watts per square mile. Your typical FM radio station has a range of maybe 50 miles and is running maybe 10 kwatts, so they're doing 4 watts per square mile. This guy is doing much better. My own power/distance record, back when I was active in ham radio, was 7000 miles on about 25 watts, or 5.10204082 × 10**-7 watts per square mile.
You might wonder how it's remotely possible for there to be a gap of seven to ten orders of magnitude. Why aren't we bothered by FM radio stations on the other side of the world? There is a qualitative difference between the behavior of radio waves above and below about 30-50 MHz (the FM band starts at 88 MHz). Conditions permitting, the lower frequencies can refract in the ionosphere and come back down to earth along non-straight-line paths. That's why shortwave radio stations on other continents can be heard.
It might also be possible to ease tectonic pressures under the Canaries by making some artificial volcanoes, or making some cuts in plates to give a little more elbow room, assuming those are practical things to try to do. This would push off the problem farther into the future.
But then if big projects like those are practical, maybe it'd be practical to set up some baffles in the water around the Canaries to break up the tsunami, and intentionally trigger it at a known time.
A little later you say that it becomes fixed when an action happens from which an observer can deduce the state in question, but this still seems to assign a special role to an intelligent observer. I thought from your earlier question that you were trying to get away from that. Or does deducibility-of-state coincide with some other condition to which an intelligent observer is irrelevant?
That's an interesting idea. But I'm inclined to doubt that the tradition would last 900 years; somebody in that time would develop an independent ego and give himself a new name. Maybe people in those days couldn't really count all the way to 900, and therefore use the number the way 5-year-olds equate 100 with infinity. Or maybe using over-large numbers was an accepted form of exaggeration (the fish was THIS BIG).
I don't think the Bible is intended to be specific and factual and accurate, like comic books or cartoons or porn. It's story-telling. Enjoy it as such. Remember the words of Jack Handy: We tend to scoff at the beliefs of the ancients. But we can't scoff at them personally, to their faces, and this is what annoys me.
I just want to make sure I still get print access to the Internet. Did anybody notice if George mentioned a subscription rate? And will it come with coupons in the back for eBay and Amazon stuff?
Google has to pay the bills too. Their approach to advertising has been pretty damn palatable compared to many alternatives out there. You and I don't have the power to force them to include a !shopping flag, but what would happen if we could? There would be no ad revenue for Google because nobody would ever look at an ad. That would mean either they go out of business, or it would mean more draconian feature reductions or other wierdness to try to compensate for the loss of revenue.
The ads along the right side aren't annoying. There are things to worry about (like no more date range searching) but the ads aren't it.
That's an article mentioning the patent application. The application itself (not including diagrams) is here.
I didn't see this in the few pictures I looked at. It seems like such an obvious thing they must have thought of it. But in addition to the sidetrack, you need a merging algorithm for cars re-entering the main track. Not necessarily rocket science, but something they'll need to think about, and maybe think pretty hard if they are so fortunate as to get much volume.
Maybe China's disinterest in other parts of the world was simply because it lacked the resources to cheaply watch other parts of the world. These satellites will be in low orbits. They'll get to look at every point on the Earth. Once they're up, the Chinese need only watch the feeds for "interesting" things.
The power base of the Chinese government has been slowly eroding, due largely to the influx of investments from the West. Surveillance is power, both inside and outside the country. This is probably an attempt to increase their power, at the expense of Chinese citizens (and the rest of the world).
To maintain the acceleration, you need sunlight hitting the solar panels. When you get that far out, the sunlight's going to be very weak. By then you might have picked up plenty of speed (I haven't done the math) but at the halfway point you won't have the acceleration you had near the inner planets.
I'm older than most Slashdot readers. I'm still young enough and mentally alert enough to recognize when something is screwy. The first time I got a 419 email, I could see there was something obviously wrong. Fast-forward a very small number of decades. I'm retired, I'm out of the loop, I've probably lost a few IQ points, and I'm on a fixed income. I might not be clever enough to recognize the next scam. I might get taken to the cleaners.
Speaking as somebody a little closer to the end of his life than many here are, I find this kind of stuff very worrisome.
At the institute they LAUGED when I insisted on building a lawnmower with broadband connectivity and an IQ of 285 and a Simmering Rage circuit. But who's laughing NOW, that they're mass produced and used worldwide? Boy, I sure hope they don't ever get the idea of uniting to rise up and overthrow the humans. But I don't think they'll ever stumble across ideas like that on the Internet, so I guess we're OK for now.
If one puts aside the trivial, there is a grimness to life. There is unhappiness, poverty, social unfairness, illness, and death. Every now and then somebody cures a specific disease (though less and less in recent decades) but the great mass of dissatisfaction remains essentially unchanged. Social issues are very rarely addressed successfully.
Anybody who puts down his distractions will be faced with that reality. We mostly can't stand that experience so we pick up our distractions again. When people notice that stuff and talk about it, we tell them to stop being a bummer.
New distractions are required frequently so we don't have time to remember we're distracting ourselves, and we just think it's how life really is. This makes the vendors of distractions wealthy. It's big business.
I once went to a great dharma talk by a teacher from Hawaii. He talked about another teacher in Thailand whose great innovation was to bring dissatisfaction out of the closet -- people normally try to avoid talking about it, turn it into a taboo, say that talking about is wimpy and whiney. This guy brought it out into the light and encouraged his students to look at it from every angle, and grapple with their reactions to it.
I won't say I went home and followed that advice. Trying that would have at least been interesting, and at best might have made me a much happier person in the long run. But it was an interesting talk. If I ever go to Hawaii, I hope to find that guy again.
800 miles length of pinwheel arms
13422.3 MPHs ground speed of pinwheel
2.9529 seconds to grab the cable
11.2347 minutes riding the pinwheel
8.96209 MPSs speed when leaving the pinwheel
5 pinwheel rotations til next try
112.347 minutes til next try
231.425 miles to next try
If you miss the 2-second capture window, you can wait for the next try. As previously noted, the pinwheel requires as many landings as launches to avoid orbit decay.
I think you may be incorrectly envisioning how the catching would work. If you're standing under the perigee point, the rock is going overhead in a horizontal direction (from left to right, for sake of argument), and the problem to be solved is that its horizontal velocity isn't as much as you'd like, so the orbit won't take it as high as you want.
As the rock is going by, there is a ship coming in from Mars, quickly overtaking the rock from the left. The rock shoots out a rope and the ship catches it. Now the ship races ahead of the rock and drags it rightwards. The ship wants to slow down so it can land, the rock wants to speed up, so this is a win-win situation. Then the rock starts reeling in the rope to slow the ship down even more (and also speed itself up more).
Eventually the ship is going slow enough so it lets go of the rope, and glides gently down into the atmosphere, and the rock's orbit is pumped back up to where it was before the previous ship launched.
Here's my understanding with the space elevator. The most serious proponent these days is a guy named Bradley Edwards who came out of one of the national labs. His idea involves beaming power up to the climber from the ground:
He makes a case that you don't want the climber to carry its own fuel. Anyway, GEO is 35800 km up, so if you're going 200 km/hour, it takes 7.45 days to get there.I showed this idea to a co-worker and he raised this point: if the passenger is delivering fuel to the rock, the energy content of that fuel would have to be exactly the same as it would have taken the passenger to get into orbit by himself. Conservation of energy and all that.
There's still a winning situation, though, which is where instead of pumping the orbit with fuel deliveries, you pump it by catching returning spaceships and decelerating them. As long as the rock collects as much momentum landing ships as it spends launching them, this is a workable system.
Maybe when the rock is near apogee it could throw out a solar sail, but I think the energy it would get per orbit doing that would be negligible compared to the energy cost of launching a ship. So catching ships is probably the winning idea.
That sounds like a good approach. It probably makes sense to start out with a metal skeleton in the desired orbit, with lots of places onto which chunks of asteroid can be duct-taped as they become available.
One way to pump up the orbit is to bring in and attach new asteroidal chunks when the framework is at apogee, and moving relatively slowly, and the chunk is coming in from far away and probably moving a good deal faster. This assumes we're good shooting cables at things and attaching them, but we need that skill anyway to use the thing for launches.
I haven't yet thought through the process of using momentum from returning ships to pump up the orbit, but if the rest of this idea is feasible, presumably that would be as well.
I've gotten curious enough about this stuff that I've started learning a little bit about orbital mechanics. I've written some Python code to do the calculations for this stuff. Here's the asteroid's orbit:
This needs my libraries for physical units and orbits, and produces these results:Do you think it's wise to irritate the moderators and risk orbital decay yourself?
Doh! I meant 1900 meters per second, not kilometers.