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Comment: Re:von Neumann probes (Score 2) 390

this planet is overrun with microorganisms, everywhere we look, how do we know were aren't the von neumann probes?

we are self replicating, bacterial spores can survive extremely long periods in a vacuum so it stands to reason they could planet hop and there are some theories life here might have come here from mars anyway.

maybe we just can't see the forest for the trees.

Comment: Re:Assumptions define the conclusion (Score 1) 574

by leonardluen (#48509961) Attached to: Hawking Warns Strong AI Could Threaten Humanity

a) there is no upper limit on intelligence.

There is no limit until the intelligence has co-opted all material in the visible universe to perform calculations and further its own intelligence. granted such an intelligence would be working on an entirely different timescale than our own.

b) Since the AI is smarter than us, this means it can design a smarter version of itself.

i grant you this is a pretty big assumption considering we haven't yet made an true AI to begin with.

c) The AI has a "desire" to create a better version of itself

it is probably safe to assume this is will be an innate desire of any true AI that we create, because one of our own reasons that we desire to create AI is for it to be able to adapt itself and to learn and react better to whatever task we have assigned to it.

d) The AI doesn't have the foresight to see that the "better" versions would eventually replace the original AI as well as humans.

you are assuming the AI would care if it is replaced by a better version of itself. or that it wouldn't be more of an upgrade of the existing one than a replacement.

Comment: Re:Quantum Mechanics and Determinism (Score 1) 335

A large number of quantum particles seem to act in a deterministic way but this is simple the law of large numbers.

it should be pointed out that our computers are built on this system as well, not just our brains.

if the universe is not deterministic then how can our computers be?


"Police Detector" Monitors Emergency Radio Transmissions 215

Posted by samzenpus
from the warning-warning-warning dept.
schwit1 writes A Dutch company has introduced a detection system that can alert you if a police officer or other emergency services official is using a two-way radio nearby. Blu Eye monitors frequencies used by the encrypted TETRA encrypted communications networks used by government agencies in Europe. It doesn't allow the user to listen in to transmissions, but can detect a radio in operation up to one kilometer away. Even if a message isn't being sent, these radios send pulses out to the network every four seconds and Blu Eye can also pick these up, according to The Sunday Times. A dashboard-mounted monitor uses lights and sounds to alert the driver to the proximity of the source, similar to a radar detector interface.

Comment: Re:We're ignoring them... (Score 1) 406

by leonardluen (#48143287) Attached to: Flight Attendants Want Stricter Gadget Rules Reinstated

i was wondering that myself.

the wikipedia article on water landing lists about 30 commercial airplanes that either had to ditch or in some other way ended up in the water.

at least 2 of the planes didn't have any floatation devices at all.
and apparently this flight is what started all the safety demonstrations for over-water flights. because a bunch of passengers died after they panicked and refused to leave the plane after it had to ditch in the ocean ocean..

They feared the rough seas and the possibility of sharks and had refused to leave the sinking aircraft to board life rafts

though i don't really see how safety training would have made much of a difference for that, as i don't recall it normally covering rough seas or sharks.

Comment: Re: Umm no (Score 1) 470

by leonardluen (#48036147) Attached to: The Physics of Space Battles

apparently the bigger threat to the A10 was flame-out of the engines due to the exhaust from the gun depriving them of oxygen. This had happened while in testing and so they had to add internal igniters to the engine that fire when the gun is fired to keep the engines burning.

so the idea is you send the platform towards the target from long distance to keep yourself safe. it is primarily un-powered and just coasting so the enemy can't detect additional heat or radiation from your thrusters to give away that the platform is coming. when it gets close it swivels with the gyros to correct any aim towards the target, which may have moved since you sent the platform, but hopefully now you are much closer to the target, and they have much less time to react. It then fires its gun. if the target is directly in front of you, then using your math you get a good about 1k shots off before you stop relative to the target. however even after that the velocity of your rounds are still sufficient to cause damage, and maybe you can fire an additional 500 rounds that are still lethal. the last of which would be traveling around 500m/s towards the target, of course this is all ignoring the loss of weight due to the ammo being fired

even if the target is directly to your side relative to your direction of movement you can probably get a good 500 shots off towards it at potentially lethal velocity. if on the other hand you have passed the target before you fire, then it is too late and there is possibly no point in firing as your rounds would not reach the target. so you just need to make sure you fire before this.

Comment: Re: Umm no (Score 1) 470

by leonardluen (#48032363) Attached to: The Physics of Space Battles

oops, i guess i missed this part "but the complete weapon, with feed system and drum, weighs 4,029 pounds (1,828 kg)"

so the platform would might have to be up to 5k to 6k kg, which is around the size of a geostationary communication satellite.
but would then allow us to fire off 7k to 9k rounds before we stop the platform. the GAU-8 fires at 3900rpm, so this is only a 2 to 3 second burst.

Comment: Re: Umm no (Score 1) 470

by leonardluen (#48032317) Attached to: The Physics of Space Battles

the GAU-8 fires a 0.69 kg round at a muzzle velocity of 990 m/s, the gun itself weighs 280kg we will use that as a starting point. according to a random website a "medium sized satellite" would be around 1000kg so lets use that for an estimate to the size of our entire thing to include electronics and such. so if my math is right each round fired would add about 0.683m/s of backwards velocity to the platform. say the platform was traveling towards the target at around 1000 m/s in the begining then you could fire off around 1500 rounds before the platform comes to a dead stop relative to the target. and the first rounds you fired would be traveling nearly 2k m/s towards the target.

Clearly the only way to resolve this argument would be for the USAF to let us borrow an A10 and fire the gun! not entirely sure what it would prove, but it would be fun.


Comment: Re: Umm no (Score 1) 470

by leonardluen (#48026537) Attached to: The Physics of Space Battles

what is your point? if you have gyros to control orientation and aim you probably have computers and some sensors to aim. the gun platform is now much closer to the target than the original ship from where you had launched it, so it should also be much easier to hit the target now. the target will also have less time to react to the projectile and move out of the way now.

but to fire projectiles at a moving target you have to fire ahead of it so the projectiles and the target meet.

this is already a solved problem. we already do it on earth with patriot missile system. and some of the targets they take down are moving faster than they do.

the amount of thrust used to fire the projectiles that way will push your gun and whatever it's mounted to, backward with the exact same force.

umm...so you mean just like you see in the movies where the guy shooting the gun gets thrown across the room, just like the guy he shot at?

the gun platform will already have velocity towards the target. all it is doing is getting in closer to the intended target, correcting the aim, and then shooting a projectile smaller than itself. (bonus points if the platform itself also hits the target, but this isn't needed). yes there will be some kickback when you fire, but it doesn't necessarily matter since you don't care if the platform itself hits. you already have velocity towards the target any more you can add to the projectile is a bonus. in addition you could either add extra mass to the platform to help counteract this kick, or add rockets to it that fire off just before you fire the projectile so that you can impart the most velocity possible into the projectile towards the target.

and actually it might be good to calculate the charge so that once the projectile is fired, it takes all forward momentum away from the gun platform relative to the target and parks it right in front of the enemy, just being a nuisance in their way. though you would probably want to fry the electronics so they can't easily reload it and send it back.

The absent ones are always at fault.