The amount of energy required depends on the time you have for the trip, if the "atacking" civilization has enough time, it's trivial to speed up to something like 0.5 C and send them back home.
Perhaps, but the real gotcha is the deceleration you'll need to do before you reach home. The energy required to decelerate from 0.5C back to a (relative) stop is non-trivial, and worse, you'll have to carry all the necessary fuel/reactant to do the deceleration with you, which means a lot more mass to accelerate in the first phase. That's why the cost of space travel goes up exponentially as you add mass to the payload.
after the initial wait of maybe 50-100 years you get a constat stream of ships coming from all around the galaxy
Ships that would either whizz right by you, crash into you at relativistic speeds (with presumably fatal results), or have to spend most of their payload capacity decelerating before they got to you.
Gun enthusiasts who keep guns in the house teach their kids about guns. Conservatives or not.
No doubt. But kids are known for doing stupid things, even when they have been carefully told not to. Given that, I don't see anything wrong (at least in principle) with a gun that can only be fired by its owner, and won't fire for anyone else.
Just use two grams of nanobots instead of one, one gram programed to replicate and kill/genocide and the other gram programed to replicate and build massive spacefaring ships to send back "home".
Where would the massive spacefaring ships obtain the huge amounts of energy required to make the return trip? Perhaps they could strip-mine the entire planet for it, but if they are going to be strip-mining planets, Earth is hardly the most attractive target for that.
The only people who could love this idea are liberal gun grabbers who are afraid somebody might get hurt with a gun.
I don't know, there might also be a market amongst conservative gun enthusiasts who want to keep a gun around the house, without worrying about their kids getting to them and blowing each other's heads off.
[Aliens] might have the technology and desire to invade earth.
Not if they have any economic sense in their heads. Unless the aliens have some sort of magic infinite energy source or teleportation device, the cost of transporting an invasion fleet to another solar system would be orders of magnitude higher than the value of anything they could possibly gain from Earth. And if they do have an infinite energy source or teleportation device, then they could use those inventions to provide for their needs directly, without leaving their home.
So if aliens invade, it will be for solely their own entertainment, not for economic reasons.
There's no reason to think that we'll ever put serious effort into sending signals into the black given all the other things on our plate. And there's no reason to think that any other civilization would have such extra resources either.
Sure there is... it's not like putting up a few beacons is hard to do, as evidenced by the fact that we were able to do it, unintentionally, even back in the 1920's.
Whether or not we (or any hypothetical aliens) would want to do it is another question, but certainly any technological civilization equal to or more advanced than our can do it, with very little effort. Hell, a sufficiently motivated private citizen could do it (FCC regulations notwithstanding).
I'm sorry, I wasn't aware that Mars was void of heat and water
Not entirely, but it's pretty damn close.
I also wasn't aware that we, as a species, are entirely incapable of developing robust shelters designed to protect from very hostile environments in which plants may be grown.
We, as a species, are quite capable of designing robust shelters... using the materials and manufacturing facilities that are located on Earth. In the imagined scenario, however, there is only a colony of a few dozen people living on Mars, and no help from Earth, because Earth has died for whatever reason. How will those people develop robust shelters? Do they have machines to do that? Great, what happens when their machines break down or wear out? Do they have additional machines to repair their machines? Great, what happens when those machines break down? What happens when they run out of spare parts? Etc.
To have an indefinitely self-sustaining Mars colony, you would need to have not just large-scale agriculture on Mars, but also advanced metallurgy, tool-making, industrial machine production, synthetic materials production, microchip manufacturing, large-scale mining, large-scale energy production, and everything else that we take for granted here on Earth, as well as a number of things that we don't have to do for ourselves on Earth (e.g. large-scale air and water production, intensive safety training for all colonists, so that nobody accidentally leaves the airlock open and kills everyone, psychological services for all the people who go insane from being cooped up inside for, well, pretty much the rest of their lives, with no hope of ever seeing a blue sky again... remember that on Mars, all it takes is one person to go insane, and he can easily kill everyone else just by exposing them to the environment)
Space is the future. If you don't go out there we will stagnate and disappear.
Or, the more realistic view: Space in an uninhabitable wasteland, enormously expensive to get to, and impossible to survive in for long periods without costly, regular support deliveries from Earth.
Let's face it, without some amazing and so-far-unforeseen advances in technology, any off-Earth colonies would die out within a few years of losing support with Earth. Given that, the presence or absence of those colonies isn't really relevant to the survival of mankind, which is 100% tied to the viability of Earth.
Why bother working around filters when there are fools to part money from?
That only works for so long... in particular, if you fool clients don't see any results, they are unlikely to give you any repeat business. Worse, the fools sometimes collaborate and you end up with a bad reputation as an ineffective spammer, so the first-timers might end up avoiding you as well.
A lesser problem, but still an important one, was the current IPv6 address naming system. The addresses are inherently long, but no serious effort was made to mitigate this.
So you don't think the:: zero-compression scheme is sufficient. What, in your mind, would "a serious effort" have looked like? Built-in-zlib compression? Restricting the IPv6 address space to 32 bits?
In any case, I think the idea is that if you're having to manually type in (or even think about) IPv6 addresses, you're doing it wrong. Things are supposed to auto-configure in IPv6 land.
Is this really an issue? All current desktop operating systems are dual stack capable.
"Capable" is necessary but not sufficient. To be useful, all of those devices you listed also have to be configured so that they are functional as IPv6 devices. That may be the bigger challenge at this point.
So I guess I'm not the only one to think this guy is going to die doing this stunt.
I think it's likely that he won't... he's done similarly dangerous stunts before and is still alive, so it's not like he's some clueless bozo who doesn't know what he's doing. I think he (and his support team) have analyzed the risks and believe they have a reasonable chance of success, or they wouldn't be doing it.
I think the key piece of technology here is the altimeter that automatically opens his parachute for him. He may not be conscious during most of the descent, but that doesn't mean it will be an uncontrolled descent.
Nevermind the fact that this has "massive liability" (i.e. instant class action lawsuits) written all over it;
Is it really any worse, liability-wise, than the high-speed chase that would be the alternative? What's the liability when one or more cars involved in the chase lose control and wipe out an entire Starbucks?
Can't give up your guns, but giving up mobility is fine?
That suggests the obvious compromise solution.... install OnStar (tm) on all guns. That way anyone can have a gun, but the government can shut down any guns that are being misused. Plus your gun can ask you if you are okay.
There, I solved that problem, on to the next one:^)
You can't keep sending stuff up a space elevator without bringing stuff down to compensate. Each time you haul some mass up the elevator, you rob the elevator and counterweight of orbital momentum.
I'm not a physicist so I may be wrong, but I think you are incorrect on this point. Here's what Wikipedia has to say about it:
Therefore as a payload is lifted up a space elevator, it needs to gain not only altitude but angular momentum (horizontal speed) as well. This angular momentum is taken from the Earth's own rotation. As the climber ascends it is initially moving slightly more slowly than the cable that it moves onto (Coriolis force) and thus the climber "drags" on the cable. The overall effect of the centrifugal force acting on the cable causes it to constantly try to return to the energetically favourable vertical orientation, so after an object has been lifted on the cable the counterweight will swing back towards the vertical like an inverted pendulum[citation needed]. Provided that the space elevator is designed so that the center of weight always stays above geostationary orbit[50] for the maximum climb speed of the climbers, the elevator cannot fall over. Lift and descent operations must be carefully planned so as to keep the pendulum-like motion of the counterweight around the tether point under control.
So as I understand it, you can move any amount of material up the elevator, provided you don't try to move too much at once, or move it too quickly.
Since the Moon isn't in geosynchronous orbit, the surface moves relative to the Moon you'd end up winding the cable around the planet.
Make the cable sharp enough and this would do a fine job of slicing the planet in half at the equator, so we could finally be rid of those damn South Americans. Northern hemisphere FTW!
For one thing we need a big counterweight, and the 'easiest' way to do that is to tow an asteroid into Earth orbit. I'd say building a space tug is an engineering challenge.
I don't think towing an asteroid is the easiest way; it would be much easier to just start with a very small counterweight (e.g. a rocket stage, or even nothing). That would give you a very low-payload-capacity cable. No problem, you send a very small/light elevator-car up the cable, and when it gets to the end of the cable, it stays there and becomes part of the counterweight. Now you send a slightly larger/heavier elevator-car up the cable, and when it gets to the end, it stays there too. Repeat as necessary until you have enough mass at the end of the cable to support whatever payloads you want to bring up.
And even after that, what happens when the bomb is surgically implanted?
There's probably no need to resort to surgery even, someone could just swallow a number of small timed explosives. Hell, drug smugglers have been swallowing condoms full of cocaine for years, and it (usually) works for them...
Exotic materials that are rare or nonexistent could become common place. In our current economy, it would be catastrophic. What if anyone could simply generate tons of gold, or other precious materials. Again, for simple reasons like this, such a machine would never be built.
A nuclear weapon is also catastrophic. That's why nuclear weapons are never built, either.
You may have thought you were making a joke, but that's the #1 reason that we do not have replicators yet. Sure, we *could* have the technology by now. There can't ever be any money in it.
That's also the #1 reason why we don't have open source software yet. There will never be any money in it, that's why it doesn't exist.
Anything, absolutely anything, you can get your hands on, you could reproduce at any other station. All you would need is raw material, which would simply be something with atoms. (i.e., dirt into another tangible object)
Hmm, just like alchemy. I could shovel in a pound of lead, press GO, and end up with a pound of gold. Sounds good!
One thing you are forgetting is that you'd also need energy to run your replicator device. How much energy you would need would depend on what you wanted it to do, but I suspect it would be prohibitive. As a simple example, look at the amount of energy it takes to turn water into separate hydrogen and oxygen gases.
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The amount of energy required depends on the time you have for the trip, if the "atacking" civilization has enough time, it's trivial to speed up to something like 0.5 C and send them back home.
Perhaps, but the real gotcha is the deceleration you'll need to do before you reach home. The energy required to decelerate from 0.5C back to a (relative) stop is non-trivial, and worse, you'll have to carry all the necessary fuel/reactant to do the deceleration with you, which means a lot more mass to accelerate in the first phase. That's why the cost of space travel goes up exponentially as you add mass to the payload.
after the initial wait of maybe 50-100 years you get a constat stream of ships coming from all around the galaxy
Ships that would either whizz right by you, crash into you at relativistic speeds (with presumably fatal results), or have to spend most of their payload capacity decelerating before they got to you.
Gun enthusiasts who keep guns in the house teach their kids about guns. Conservatives or not.
No doubt. But kids are known for doing stupid things, even when they have been carefully told not to. Given that, I don't see anything wrong (at least in principle) with a gun that can only be fired by its owner, and won't fire for anyone else.
Just use two grams of nanobots instead of one, one gram programed to replicate and kill/genocide and the other gram programed to replicate and build massive spacefaring ships to send back "home".
Where would the massive spacefaring ships obtain the huge amounts of energy required to make the return trip? Perhaps they could strip-mine the entire planet for it, but if they are going to be strip-mining planets, Earth is hardly the most attractive target for that.
We are in the XXI century just are beginning to see the Fusion Reactor [...] and I am certain I will die seeing one working efficiently.
Now there's an ominous sounding prophecy... :^)
The only people who could love this idea are liberal gun grabbers who are afraid somebody might get hurt with a gun.
I don't know, there might also be a market amongst conservative gun enthusiasts who want to keep a gun around the house, without worrying about their kids getting to them and blowing each other's heads off.
[Aliens] might have the technology and desire to invade earth.
Not if they have any economic sense in their heads. Unless the aliens have some sort of magic infinite energy source or teleportation device, the cost of transporting an invasion fleet to another solar system would be orders of magnitude higher than the value of anything they could possibly gain from Earth. And if they do have an infinite energy source or teleportation device, then they could use those inventions to provide for their needs directly, without leaving their home.
So if aliens invade, it will be for solely their own entertainment, not for economic reasons.
There's no reason to think that we'll ever put serious effort into sending signals into the black given all the other things on our plate. And there's no reason to think that any other civilization would have such extra resources either.
Sure there is... it's not like putting up a few beacons is hard to do, as evidenced by the fact that we were able to do it, unintentionally, even back in the 1920's.
Whether or not we (or any hypothetical aliens) would want to do it is another question, but certainly any technological civilization equal to or more advanced than our can do it, with very little effort. Hell, a sufficiently motivated private citizen could do it (FCC regulations notwithstanding).
I've devised an algorithm that tells me with 100% certainty that this guy's ego is way too far up his ass.
Random nobody spends 45 seconds skimming an article on the Internet, feels qualified to throw insults. Details at 11.
I'm sorry, I wasn't aware that Mars was void of heat and water
Not entirely, but it's pretty damn close.
I also wasn't aware that we, as a species, are entirely incapable of developing robust shelters designed to protect from very hostile environments in which plants may be grown.
We, as a species, are quite capable of designing robust shelters... using the materials and manufacturing facilities that are located on Earth. In the imagined scenario, however, there is only a colony of a few dozen people living on Mars, and no help from Earth, because Earth has died for whatever reason. How will those people develop robust shelters? Do they have machines to do that? Great, what happens when their machines break down or wear out? Do they have additional machines to repair their machines? Great, what happens when those machines break down? What happens when they run out of spare parts? Etc.
To have an indefinitely self-sustaining Mars colony, you would need to have not just large-scale agriculture on Mars, but also advanced metallurgy, tool-making, industrial machine production, synthetic materials production, microchip manufacturing, large-scale mining, large-scale energy production, and everything else that we take for granted here on Earth, as well as a number of things that we don't have to do for ourselves on Earth (e.g. large-scale air and water production, intensive safety training for all colonists, so that nobody accidentally leaves the airlock open and kills everyone, psychological services for all the people who go insane from being cooped up inside for, well, pretty much the rest of their lives, with no hope of ever seeing a blue sky again... remember that on Mars, all it takes is one person to go insane, and he can easily kill everyone else just by exposing them to the environment)
Space is the future. If you don't go out there we will stagnate and disappear.
Or, the more realistic view: Space in an uninhabitable wasteland, enormously expensive to get to, and impossible to survive in for long periods without costly, regular support deliveries from Earth.
Let's face it, without some amazing and so-far-unforeseen advances in technology, any off-Earth colonies would die out within a few years of losing support with Earth. Given that, the presence or absence of those colonies isn't really relevant to the survival of mankind, which is 100% tied to the viability of Earth.
Why bother working around filters when there are fools to part money from?
That only works for so long... in particular, if you fool clients don't see any results, they are unlikely to give you any repeat business. Worse, the fools sometimes collaborate and you end up with a bad reputation as an ineffective spammer, so the first-timers might end up avoiding you as well.
Fortunately, this is generally not an issue for any business with a competent network admin staff.
That's all well and good for them, but what about the other 98% of the world? ;^)
A lesser problem, but still an important one, was the current IPv6 address naming system. The addresses are inherently long, but no serious effort was made to mitigate this.
So you don't think the :: zero-compression scheme is sufficient. What, in your mind, would "a serious effort" have looked like? Built-in-zlib compression? Restricting the IPv6 address space to 32 bits?
In any case, I think the idea is that if you're having to manually type in (or even think about) IPv6 addresses, you're doing it wrong. Things are supposed to auto-configure in IPv6 land.
Is this really an issue? All current desktop operating systems are dual stack capable.
"Capable" is necessary but not sufficient. To be useful, all of those devices you listed also have to be configured so that they are functional as IPv6 devices. That may be the bigger challenge at this point.
So I guess I'm not the only one to think this guy is going to die doing this stunt.
I think it's likely that he won't... he's done similarly dangerous stunts before and is still alive, so it's not like he's some clueless bozo who doesn't know what he's doing. I think he (and his support team) have analyzed the risks and believe they have a reasonable chance of success, or they wouldn't be doing it.
I think the key piece of technology here is the altimeter that automatically opens his parachute for him. He may not be conscious during most of the descent, but that doesn't mean it will be an uncontrolled descent.
Nevermind the fact that this has "massive liability" (i.e. instant class action lawsuits) written all over it;
Is it really any worse, liability-wise, than the high-speed chase that would be the alternative? What's the liability when one or more cars involved in the chase lose control and wipe out an entire Starbucks?
Can't give up your guns, but giving up mobility is fine?
That suggests the obvious compromise solution.... install OnStar (tm) on all guns. That way anyone can have a gun, but the government can shut down any guns that are being misused. Plus your gun can ask you if you are okay.
There, I solved that problem, on to the next one :^)
You can't keep sending stuff up a space elevator without bringing stuff down to compensate. Each time you haul some mass up the elevator, you rob the elevator and counterweight of orbital momentum.
I'm not a physicist so I may be wrong, but I think you are incorrect on this point. Here's what Wikipedia has to say about it:
Therefore as a payload is lifted up a space elevator, it needs to gain not only altitude but angular momentum (horizontal speed) as well. This angular momentum is taken from the Earth's own rotation. As the climber ascends it is initially moving slightly more slowly than the cable that it moves onto (Coriolis force) and thus the climber "drags" on the cable.
The overall effect of the centrifugal force acting on the cable causes it to constantly try to return to the energetically favourable vertical orientation, so after an object has been lifted on the cable the counterweight will swing back towards the vertical like an inverted pendulum[citation needed]. Provided that the space elevator is designed so that the center of weight always stays above geostationary orbit[50] for the maximum climb speed of the climbers, the elevator cannot fall over. Lift and descent operations must be carefully planned so as to keep the pendulum-like motion of the counterweight around the tether point under control.
So as I understand it, you can move any amount of material up the elevator, provided you don't try to move too much at once, or move it too quickly.
I want to order pizza and ice cream on earth, delivered by cannon.
After 5000 g's, pretty much anything you order is going to arrive looking like ice cream.
Since the Moon isn't in geosynchronous orbit, the surface moves relative to the Moon you'd end up winding the cable around the planet.
Make the cable sharp enough and this would do a fine job of slicing the planet in half at the equator, so we could finally be rid of those damn South Americans. Northern hemisphere FTW!
For one thing we need a big counterweight, and the 'easiest' way to do that is to tow an asteroid into Earth orbit. I'd say building a space tug is an engineering challenge.
I don't think towing an asteroid is the easiest way; it would be much easier to just start with a very small counterweight (e.g. a rocket stage, or even nothing). That would give you a very low-payload-capacity cable. No problem, you send a very small/light elevator-car up the cable, and when it gets to the end of the cable, it stays there and becomes part of the counterweight. Now you send a slightly larger/heavier elevator-car up the cable, and when it gets to the end, it stays there too. Repeat as necessary until you have enough mass at the end of the cable to support whatever payloads you want to bring up.
Why should whales get dibs on the whole ocean.
Because they got there first?
And even after that, what happens when the bomb is surgically implanted?
There's probably no need to resort to surgery even, someone could just swallow a number of small timed explosives. Hell, drug smugglers have been swallowing condoms full of cocaine for years, and it (usually) works for them...
Exotic materials that are rare or nonexistent could become common place. In our current economy, it would be catastrophic. What if anyone could simply generate tons of gold, or other precious materials. Again, for simple reasons like this, such a machine would never be built.
A nuclear weapon is also catastrophic. That's why nuclear weapons are never built, either.
You may have thought you were making a joke, but that's the #1 reason that we do not have replicators yet. Sure, we *could* have the technology by now. There can't ever be any money in it.
That's also the #1 reason why we don't have open source software yet. There will never be any money in it, that's why it doesn't exist.
Anything, absolutely anything, you can get your hands on, you could reproduce at any other station. All you would need is raw material, which would simply be something with atoms. (i.e., dirt into another tangible object)
Hmm, just like alchemy. I could shovel in a pound of lead, press GO, and end up with a pound of gold. Sounds good!
One thing you are forgetting is that you'd also need energy to run your replicator device. How much energy you would need would depend on what you wanted it to do, but I suspect it would be prohibitive. As a simple example, look at the amount of energy it takes to turn water into separate hydrogen and oxygen gases.