Hmm. Checks certificate. Hmm still says Degree in Physics. Oh well.
a) sonic booms occur above mach 1 not at mach 1. They are produced continuously. They are going to be more intense at higher mach.
b)&c) Making a mach 27 object survive at all is not easy. IRC no vehicle except rockets have exceeded about mach 5 or so (give or take a couple of mach), and they do it OUTSIDE the atmosphere. Reentering space vehicles do sort of enter the atmosphere but they deliberately lose a lot of speed at high altitude in thin air, so that's not really comparable.
d) orbital mechanics... what can I say... there are three types of orbits around anything; elliptical, escape and hyperbolic. Any object with less than escape velocity is in an elliptical orbit. These orbits are generally stable. It's theoretically possible to get a decaying solar orbit, but not practically; decaying orbits need atmosphere- the sun doesn't really have this.
The orbital velocity of the earth is 67000 miles per hour BTW. Escape velocity of the earth is ~25000 miles per hour, so I was way off- its more like mach 60 or so. Forget about it; it ain't going to work.
I suggest you pull a book on orbits and read it for once; I know I have. I've also played around on computer simulations. You will find its generally a good idea not to make assumptions about people online based on little to no evidence.
Oh yeah, you mention rail guns. Rail guns have achieved about 5 km/s (about mach 12ish); but they suffer from severe rail erosion. I'm not aware of any that can go faster than this. Coil guns don't have any rails but top out at about 2 km/s right now, although faster is probably doable.
Nope, sonic booms only occur ABOVE mach1. They occur throughout the transonic flight regime.
As to intersecting the sun- this might be best achieved by firing the gun roughly horizontally, 35 degrees east north east at about mid-day so that it leaves the earth at exactly the earths orbital speed plus earth escape velocity; and gains the earths rotation speed.
I'm no expert (slight modesty), but there's a few problems with this idea:
a) sonic booms- concorde at Mach 2 gives big bangs for tens of miles; Mach 27+ sonic booms are going to reach hundreds or thousands of miles
b) failure modes- e.g. it doesn't quite reach escape velocity due to a coil failure and lands in the middle of Tokyo or something, causing not only dirty nuclear fallout that lasts 10's of thousands of years, but also straightforward meteorite style damage; or what if one of the coils shatters and hits one of the barrels at mach 20- not nice; really not nice.
c) ablation- the first 100m will probably lose atleast a couple of mach and quite a bit of the casing
d) solar orbits don't decay very much, for example the earth would have burnt up long ago
e) Orbital mechanics issues: to a reasonable approximation anything fired from the earth, still intersects the earths orbit twice per year, and takes a year to complete 1 orbit. You have to fire it quite fast to avoid this issue. It takes a LOT of speed to fire something from the earth and get it to impact the Sun; off-hand you'd need maybe Mach 32 or so
The problem with Hydrogen is that to make it, the process is only 20% efficient. This compares unfavourably with other processes, e.g. batteries are more like 50% efficient. Still, if you have a pollution free, inexaustable source of energy ('the Sun') this doesn't matter as much.
The other problem with Hydrogen is its low density. This can be improved by compressing it or storing it in a metal 'catalyst', but then it stops being low density and becomes rather too heavy for cars and such like.
Agreed. Particularly on an open source product it makes no difference.
Short of special hardware with BIOS support, or a password that has to be manually typed in to boot the firewall (you'd better have a *good* UPS!); there's no known way to do that securely.
>Not true. Most of the lower protozoa (things like Euglena) don't have sexual reproduction, and some
>animals and plants have secondarily lost it, like certain rotifers.
Not sure which animals have lost this; but protozoa and rotifers.
>Plus, even among organisms which do have sexual reproduction, many can reproduce asexually indefinitely.
There is some question over this apparently. How many generations do you allow the asexual reproduction to run before declaring that they can do so indefinitely? 30? 100? 1000? Why that number?
No, black and green fly, various bacteria and other asexually reproducing organisms have been around far longer than mankind has.
There's pro's and cons to asexual reproduction. On the one hand, you reproduce more quickly (some black fly are even born pregnant!), on the other a disease can swing through and get all of your sibblings because you are genetic clones.
All known organisms except bacteria do both asexual and sexual reproduction. There seems to be limits to how many generations purely asexual reproduction can occur before the damage kills. Not quite sure how bacteria deal with this, but probably their genome is shorter and they have extensive genetic repair mechanisms and possibly use some DNA swapping, plus they reproduce really fast...
It may be that women's eggs would age more slowly as well.
Even if this wasn't the case the genes would still be spread by men. If a man at 80 is still looking like he did at 50 then he can have children at that age.
Besides, there is precedent. Tortoises live a very long time. This is because they are well protected by their shells, and hence can live a long while. Their longevity genes have already spread through the population.
Birds also live much longer than they should do- in their lives they spend a very great deal of energy for their size- and yet because they are able to fly away from predators they survive many years. Compare this to say, a mouse which any cat can track down, and they live just a year or two before dying of old age. Bats live a lot longer, because they too can fly.
I don't really agree with your analysis, but even if you are right the men can still father more children. If a man looks younger for longer, he can divorce and remarry fertile women more easily. The men that have the slower aging genes can thus spread them more widely. The women may WANT to bear his children.
I do this for a living, so I know. At the top of the food chain is the SONET/SDH telecommunications network. That works at between OC12 (660 Mbit/s) and OC768 (40+Gb/s) rates, and go typical distances of a hundred kilometers (upto a thousand). And these rates can be done many times on difference frequencies of light (DWDM) on a single fibers; and you can have multiple fibers between offices as well.
At present, 6.4 Terabits can be shifted on a single fiber, although I don't think that has been deployed in any serious way, ~100Gb/s or so are much more common. If you need more bandwidth, add another wavelength (cost: a millionish); or if the fiber is full (rare right now, but will happen more and more often in a few years or a decade), then you need to lay new fibers- that costs 100s of millions; but we are talking significant bandwidth from that- you don't lay 1 fiber you lay 50 or so and keep most of them for expansion or sell them to other telecoms companies to pay for your layout.
> The average lifespan is only that long thanks to modern advances in medicine, disease cures, etc.
Actually, most people die of old age now, that's historically unusual- Cancer is a disease of old age, mostly; as is heart disease.
The reason that the average old age is as it is, is believed to be evolutionary.
In human history, and to a far lesser extent now, The human body has a certain amount of energy and other resources to play with; ultimately there's only so much food available; and the body has to balance growth, reproduction and repair (repair including genetic repair to head off cancer).
The ideal amount of repair is linked to how long you expect to live- what's the point in repairing the body so that it would survive to 500, if by doing, say, 50% less repair you can live to be 85, when life expectency is only 35-50 anyway due to war, disease, accident etc. Evolution would change the genome to spend the energy reproducing a little more; as that way the genes will survive more often.
Right now, we've messed with life expectancy. That means that, unless we do something, the human genome is going to tend to become longer lived, over the next few thousand generations (since, obviously, people who age more slowly will have more children; and their genes will spread.)
This will involve changes to prevent cancer in other ways than this on the p53 gene, as well as changes to many other genes to ensure survival past the point we live to now.
Your idea is close to a more workable one I had. I don't like censorship much but here goes:
Most censorship schemes try to mark all the 'bad' stuff. Don't do that. Instead mark all the 'good' stuff, and only allow kids to see that. If it hasn't been marked, assume it is no good for kids.
There's much less safe-for-kids stuff on the net than unsafe stuff, so it's easier to enforce, and you only get it rated if it is ok for the kids to see.
To mark it, you have a censor sign it as 'universal rating in UK' (cryptographic signature) or 'ok for below 18s in USA', depending on where you live; or 'contains graphic violence for USA' or whatever, with any arbitrary level of granularity- multiple markings are fine.
ISP/OSs should only allow kids access to certain stuff signed by appropriate censors; appropriate to the morays of the ISP/country- so, if the age of consent in Japan is 14, then 17 year old US teenagers will only be able to see stuff suitable for 13 or under on Japanese web sites. Adults in Moslem countries will probably be able to see Walt Disney films if they're lucky.
But who censors? I think that a Slashdot style censorship scheme could be made to work, or else you can write a web page and offer it up to be checked for kid friendliness; possibly for a small fee.
The danger of all this is that the politicians will start using it as a form of censorship for adults as well.
> The cable is not rigid, and unless I'm mistaken, it is perpendicular to the Earth's surface, so I don't see any way it can transmit a moment to the Earth.
You're exactly right. It can't be perpendicular to the earths surface and transmit moment to the Earth.
In fact, as an object goes up the tether, it tends to drag the tether to the west, because the tether is accelerating the payload sideways as it goes up towards orbit at geosynchronous altitude- it needs a few klicks/sec up there relative to the ground, and its stationary at ground level, so it accelerates as it goes up the cable. The only way a cable can do that is to form a shallow v shape.
This V shape means the tether is tilted to the ground. The tension on the tether at the ground will therefore pull on the earth and slow it down; but I wouldn't exactly lose sleep over that bit.
In fact, the tether's position can be controlled by moving the payload up and down on the tether and careful timing.
Re:Hey, let's build a prison just for them
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Crazy Stats on Spam
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· Score: 2
Starvation? They're spammers! Not murderers! Death's too good for them!;-)
Incidentally, you left out the bit about making their meal ticket with an 'obvious' subject like: 'Make money fast', that varies on a meal to meal basis.;-)
"There's a sucker born every minute."
The real point is that we don't want people to become suckers- the law is supposed to protect them to some extent.
> A full 35,000km long space elevator would not be practical.
That's what I thought, but read the paper. He claims it's possible; and describes how, how much and how long. The carbon nanotubes are strong enough now; or atleast that's the claim.
That would probably be bad, although it might sort itself out, I don't know if anyone really knows what happens. I think that the tether would be designed to be an insulator.
I don't think Redmond cares whether they are right or not. What they are doing is to give some [apparent] reasons for those managers that have chosen Microsoft software, or may be about to do so, that their chosen path [folly] is "correct", if anyone asks [laughs at them- and well they might.]
We tend to think of orbits as being circular and completely predictable. In theory this is true. In practice the orbit is affected by solar effects, magnetic effects on the vehicle (depends on the shape and materials of the vehicle), perturbations by the moon, saturn, the sun, the non spherical nature of the earths gravity field, etc. etc.
In practice you can't predict the orbit exactly, so the rules say that if the vehicle is coming within a certain distance (a few miles), then measures have to be taken, ranging from moving the vehicle to piling into the escape vehicle, depending on the predicted distance.
Re:This is a weapon of massless destruction
on
Lunar Lasers
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· Score: 2
Rectenna is short for rectifying antenna. You put it flat on the ground.
"Not to be taken internally.";-)
Re:This is a weapon of massless destruction
on
Lunar Lasers
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· Score: 2
Slashdot Mirror
No, it's still impossible the delta-v for this is much too large even with a rail gun or coil gun with any current technology.
Hmm. Checks certificate. Hmm still says Degree in Physics. Oh well.
a) sonic booms occur above mach 1 not at mach 1. They are produced continuously. They are going to be more intense at higher mach.
b)&c) Making a mach 27 object survive at all is not easy. IRC no vehicle except rockets have exceeded about mach 5 or so (give or take a couple of mach), and they do it OUTSIDE the atmosphere. Reentering space vehicles do sort of enter the atmosphere but they deliberately lose a lot of speed at high altitude in thin air, so that's not really comparable.
d) orbital mechanics... what can I say... there are three types of orbits around anything; elliptical, escape and hyperbolic. Any object with less than escape velocity is in an elliptical orbit. These orbits are generally stable. It's theoretically possible to get a decaying solar orbit, but not practically; decaying orbits need atmosphere- the sun doesn't really have this.
The orbital velocity of the earth is 67000 miles per hour BTW. Escape velocity of the earth is ~25000 miles per hour, so I was way off- its more like mach 60 or so. Forget about it; it ain't going to work.
I suggest you pull a book on orbits and read it for once; I know I have. I've also played around on computer simulations. You will find its generally a good idea not to make assumptions about people online based on little to no evidence.
Oh yeah, you mention rail guns. Rail guns have achieved about 5 km/s (about mach 12ish); but they suffer from severe rail erosion. I'm not aware of any that can go faster than this. Coil guns don't have any rails but top out at about 2 km/s right now, although faster is probably doable.
>Sonic booms occur at mach 1
Nope, sonic booms only occur ABOVE mach1. They occur throughout the transonic flight regime.
As to intersecting the sun- this might be best achieved by firing the gun roughly horizontally, 35 degrees east north east at about mid-day so that it leaves the earth at exactly the earths orbital speed plus earth escape velocity; and gains the earths rotation speed.
I'm no expert (slight modesty), but there's a few problems with this idea:
a) sonic booms- concorde at Mach 2 gives big bangs for tens of miles; Mach 27+ sonic booms are going to reach hundreds or thousands of miles
b) failure modes- e.g. it doesn't quite reach escape velocity due to a coil failure and lands in the middle of Tokyo or something, causing not only dirty nuclear fallout that lasts 10's of thousands of years, but also straightforward meteorite style damage; or what if one of the coils shatters and hits one of the barrels at mach 20- not nice; really not nice.
c) ablation- the first 100m will probably lose atleast a couple of mach and quite a bit of the casing
d) solar orbits don't decay very much, for example the earth would have burnt up long ago
e) Orbital mechanics issues: to a reasonable approximation anything fired from the earth, still intersects the earths orbit twice per year, and takes a year to complete 1 orbit. You have to fire it quite fast to avoid this issue. It takes a LOT of speed to fire something from the earth and get it to impact the Sun; off-hand you'd need maybe Mach 32 or so
Actually, that isn't the problem with Hydrogen.
The problem with Hydrogen is that to make it, the process is only 20% efficient. This compares unfavourably with other processes, e.g. batteries are more like 50% efficient. Still, if you have a pollution free, inexaustable source of energy ('the Sun') this doesn't matter as much.
The other problem with Hydrogen is its low density. This can be improved by compressing it or storing it in a metal 'catalyst', but then it stops being low density and becomes rather too heavy for cars and such like.
Agreed. Particularly on an open source product it makes no difference.
Short of special hardware with BIOS support, or a password that has to be manually typed in to boot the firewall (you'd better have a *good* UPS!); there's no known way to do that securely.
>Not true. Most of the lower protozoa (things like Euglena) don't have sexual reproduction, and some
>animals and plants have secondarily lost it, like certain rotifers.
Not sure which animals have lost this; but protozoa and rotifers.
>Plus, even among organisms which do have sexual reproduction, many can reproduce asexually indefinitely.
There is some question over this apparently. How many generations do you allow the asexual reproduction to run before declaring that they can do so indefinitely? 30? 100? 1000? Why that number?
No, black and green fly, various bacteria and other asexually reproducing organisms have been around far longer than mankind has.
There's pro's and cons to asexual reproduction. On the one hand, you reproduce more quickly (some black fly are even born pregnant!), on the other a disease can swing through and get all of your sibblings because you are genetic clones.
All known organisms except bacteria do both asexual and sexual reproduction. There seems to be limits to how many generations purely asexual reproduction can occur before the damage kills. Not quite sure how bacteria deal with this, but probably their genome is shorter and they have extensive genetic repair mechanisms and possibly use some DNA swapping, plus they reproduce really fast...
It may be that women's eggs would age more slowly as well.
Even if this wasn't the case the genes would still be spread by men. If a man at 80 is still looking like he did at 50 then he can have children at that age.
Besides, there is precedent. Tortoises live a very long time. This is because they are well protected by their shells, and hence can live a long while. Their longevity genes have already spread through the population.
Birds also live much longer than they should do- in their lives they spend a very great deal of energy for their size- and yet because they are able to fly away from predators they survive many years. Compare this to say, a mouse which any cat can track down, and they live just a year or two before dying of old age. Bats live a lot longer, because they too can fly.
I don't really agree with your analysis, but even if you are right the men can still father more children. If a man looks younger for longer, he can divorce and remarry fertile women more easily. The men that have the slower aging genes can thus spread them more widely. The women may WANT to bear his children.
I do this for a living, so I know. At the top of the food chain is the SONET/SDH telecommunications network. That works at between OC12 (660 Mbit/s) and OC768 (40+Gb/s) rates, and go typical distances of a hundred kilometers (upto a thousand). And these rates can be done many times on difference frequencies of light (DWDM) on a single fibers; and you can have multiple fibers between offices as well.
At present, 6.4 Terabits can be shifted on a single fiber, although I don't think that has been deployed in any serious way, ~100Gb/s or so are much more common. If you need more bandwidth, add another wavelength (cost: a millionish); or if the fiber is full (rare right now, but will happen more and more often in a few years or a decade), then you need to lay new fibers- that costs 100s of millions; but we are talking significant bandwidth from that- you don't lay 1 fiber you lay 50 or so and keep most of them for expansion or sell them to other telecoms companies to pay for your layout.
> The average lifespan is only that long thanks to modern advances in medicine, disease cures, etc.
Actually, most people die of old age now, that's historically unusual- Cancer is a disease of old age, mostly; as is heart disease.
The reason that the average old age is as it is, is believed to be evolutionary.
In human history, and to a far lesser extent now, The human body has a certain amount of energy and other resources to play with; ultimately there's only so much food available; and the body has to balance growth, reproduction and repair (repair including genetic repair to head off cancer).
The ideal amount of repair is linked to how long you expect to live- what's the point in repairing the body so that it would survive to 500, if by doing, say, 50% less repair you can live to be 85, when life expectency is only 35-50 anyway due to war, disease, accident etc. Evolution would change the genome to spend the energy reproducing a little more; as that way the genes will survive more often.
Right now, we've messed with life expectancy. That means that, unless we do something, the human genome is going to tend to become longer lived, over the next few thousand generations (since, obviously, people who age more slowly will have more children; and their genes will spread.)
This will involve changes to prevent cancer in other ways than this on the p53 gene, as well as changes to many other genes to ensure survival past the point we live to now.
Your idea is close to a more workable one I had. I don't like censorship much but here goes:
Most censorship schemes try to mark all the 'bad' stuff. Don't do that. Instead mark all the 'good' stuff, and only allow kids to see that. If it hasn't been marked, assume it is no good for kids.
There's much less safe-for-kids stuff on the net than unsafe stuff, so it's easier to enforce, and you only get it rated if it is ok for the kids to see.
To mark it, you have a censor sign it as 'universal rating in UK' (cryptographic signature) or 'ok for below 18s in USA', depending on where you live; or 'contains graphic violence for USA' or whatever, with any arbitrary level of granularity- multiple markings are fine.
ISP/OSs should only allow kids access to certain stuff signed by appropriate censors; appropriate to the morays of the ISP/country- so, if the age of consent in Japan is 14, then 17 year old US teenagers will only be able to see stuff suitable for 13 or under on Japanese web sites. Adults in Moslem countries will probably be able to see Walt Disney films if they're lucky.
But who censors? I think that a Slashdot style censorship scheme could be made to work, or else you can write a web page and offer it up to be checked for kid friendliness; possibly for a small fee.
The danger of all this is that the politicians will start using it as a form of censorship for adults as well.
> The cable is not rigid, and unless I'm mistaken, it is perpendicular to the Earth's surface, so I don't see any way it can transmit a moment to the Earth.
You're exactly right. It can't be perpendicular to the earths surface and transmit moment to the Earth.
In fact, as an object goes up the tether, it tends to drag the tether to the west, because the tether is accelerating the payload sideways as it goes up towards orbit at geosynchronous altitude- it needs a few klicks/sec up there relative to the ground, and its stationary at ground level, so it accelerates as it goes up the cable. The only way a cable can do that is to form a shallow v shape.
This V shape means the tether is tilted to the ground. The tension on the tether at the ground will therefore pull on the earth and slow it down; but I wouldn't exactly lose sleep over that bit.
In fact, the tether's position can be controlled by moving the payload up and down on the tether and careful timing.
Starvation? They're spammers! Not murderers! Death's too good for them! ;-)
;-)
Incidentally, you left out the bit about making their meal ticket with an 'obvious' subject like: 'Make money fast', that varies on a meal to meal basis.
Actually, to be correct; the 8M pdf file is the phase II paper, which was written later; and contains more information if anything; but less text.
Yeah, make them read their own spam mail once for each person they sent it to. Or let's say twice. There has to be some punishment involved. ;-)
I think the normal phrase is:
"There's a sucker born every minute."
The real point is that we don't want people to become suckers- the law is supposed to protect them to some extent.
> A full 35,000km long space elevator would not be practical.
That's what I thought, but read the paper. He claims it's possible; and describes how, how much and how long. The carbon nanotubes are strong enough now; or atleast that's the claim.
That would probably be bad, although it might sort itself out, I don't know if anyone really knows what happens. I think that the tether would be designed to be an insulator.
Surface to air missiles and/or aircraft.
I don't think Redmond cares whether they are right or not. What they are doing is to give some [apparent] reasons for those managers that have chosen Microsoft software, or may be about to do so, that their chosen path [folly] is "correct", if anyone asks [laughs at them- and well they might.]
We tend to think of orbits as being circular and completely predictable. In theory this is true. In practice the orbit is affected by solar effects, magnetic effects on the vehicle (depends on the shape and materials of the vehicle), perturbations by the moon, saturn, the sun, the non spherical nature of the earths gravity field, etc. etc.
In practice you can't predict the orbit exactly, so the rules say that if the vehicle is coming within a certain distance (a few miles), then measures have to be taken, ranging from moving the vehicle to piling into the escape vehicle, depending on the predicted distance.
Rectenna is short for rectifying antenna. You put it flat on the ground.
;-)
"Not to be taken internally."
Nope. They're wackos. ;-)