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Comment: What he actually said... (Score 3, Insightful) 454

by Normal_Deviate (#47505623) Attached to: MIT's Ted Postol Presents More Evidence On Iron Dome Failures
I did RTFA, and he makes two real claims. His primary claim is that the iron dome system must be failing, because when the interceptor approaches the target from anything other than head on, the interceptor will fire its warhead at the wrong time. He implies that this failure is an inevitable consequence of geometry, but I don't see it. If you actually look at the diagrams, the interceptor has just a good a shot when approaching (say) from behind as from in front. In fact the odds look better to me from behind or the side, as the crossing speeds are lower and the shrapnel fan might actually run down the length of the target. The interceptor just needs to fire its warhead at a different moment. But his diagrams all show the warhead firing at the wrong time, for reasons that are not made clear.

Is the iron dome system smart enough to account for basic geometry? I would think so, since the problem is pretty simple, and the approach angle will be known by the radar even before launch. But I don't really know. And I don't think he does either.

His second claim might be more credible. He says that in hundreds of pictures of intercepts, only one clearly shows detonation of the incoming rocket. I don't know if this is true, and I don't trust his claim. But if it is true then it cries out for explanation.

Comment: Re:Reminds me of Control Theory (Score 0) 401

The stabilizer is self interest, because people don't like to be poor. And control is indeed the key. Pass enough laws to prevent people from adapting to change, and collapse is inevitable. As inevitable as the statists who caused the collapse blaming it on the one percent who made civilization possible in the first place.

Comment: We already did this experment with porn (Score 1) 120

by Normal_Deviate (#44701343) Attached to: Study Suggests Violent Video Games May Make Teens Less Violent
Remember when the feminists went after porn because it encouraged rape? Rarely has any hypothesis been so dangerously wrong, and so thoroughly disproved. And lest you think we have learned our lesson, I nervously call your attention to the subject of kiddie porn.

Comment: Re:If I recall..... (Score 2) 333

by Normal_Deviate (#41247535) Attached to: Quantum Teleportation Sends Information 143 Kilometers
I always ask this, and never get an answer. A quantum wavefunction can interfere with itself (E.g., you get interference fringes if you do the 2-slit experiment with a single photon.) But if the wavefunction is collapsed (E.g., by measuring which slit the photon goes through) then it cannot self-interfere. (The fringes disappear.)

Now the punchline. The whole point of quantum teleportation is that collapsing a particle's wavefunction will also collapse the wavefunction of a remote, entangled particle. Will that destroy the remote particle's self-interference fringes? If so, then we have our ansible.

Comment: Can we detect wavefunction collapse, or not? (Score 1) 160

by Normal_Deviate (#38245196) Attached to: Quantum Entanglement of Macroscopic Diamonds
Detecting wavefunction collapse is trivial, just look for interference between the possible states, ala the two-slit experiment. HOWEVER, if the collapse of an entangled wavefunction can be detected, than FTL information transmission is possible, because collapsing one half of an entangled pair will instantly collapse the other half, causing the interference pattern (or whatever) to disappear. So what am I missing?

Comment: Re:You are clueless if you claim such a thing (Score 4, Insightful) 1131

The IRA were, and are, Marxists in all but name. If you doubt, read the Sinn Fein manifesto, available online now. What, you never heard that on the news? How could that be? The rule, "All terrorists are collectivists or Muslims" is only rarely violated.

Comment: Re:How are we supposed to understand this? (Score 1) 1671

by Normal_Deviate (#31738230) Attached to: Wikileaks Releases Video of Journalist Killings
Ditto. They looked like guns to me, and the soldier's call of an RPG seemed reasonable. Also noteworthy: Watching a wounded guy crawl around, and not firing because he had not picked up a weapon. As for killing the rescuers, I agree that is debatable, but the purpose of war is to kill the enemy. I saw no kids.

Comment: Is this really a net gain? (Score 1) 77

by Normal_Deviate (#31639978) Attached to: Tiny Cube Drags Space Debris From Orbit
A satellite's lifetime collision risk depends on the volume of space it sweeps out before the cumulative drag adds up to a de-orbit. The sail does not reduce that volume, it just sweeps it out in a shorter time. I guess there is some net benefit, since a collision with the sail will create a smaller debris cloud.

Breaking the Squid Barrier 126

Posted by timothy
from the calimari-for-the-5000 dept.
An anonymous reader writes "Dr. Steve O'Shea of Auckland, New Zealand is attempting to break the record for keeping deep sea squid alive in captivity, with the goal of being able to raise a giant squid one day. Right now, he's raising the broad squid, sepioteuthis australis, from egg masses found in seaweed. This is a lot harder than it sounds, because the squid he's studying grow rapidly and eat only live prey, making it hard for them to keep the squid from becoming prey themselves. If his research works out, you might one day be able to visit an aquarium and see giant squid."

Music By Natural Selection 164

Posted by samzenpus
from the survival-of-the-grooviest dept.
maccallr writes "The DarwinTunes experiment needs you! Using an evolutionary algorithm and the ears of you the general public, we've been evolving a four bar loop that started out as pretty dismal primordial auditory soup and now after >27k ratings and 200 generations is sounding pretty good. Given that the only ingredients are sine waves, we're impressed. We got some coverage in the New Scientist CultureLab blog but now things have gone quiet and we'd really appreciate some Slashdotter idle time. We recently upped the maximum 'genome size' and we think that the music is already benefiting from the change."

NYT's "Games To Avoid" an Ironic, Perfect Gamer Wish List 189

Posted by Soulskill
from the more-or-less dept.
MojoKid writes "From October to December, the advertising departments of a thousand companies exhort children to beg, cajole, and guilt-trip their parents for all manner of inappropriate digital entertainment. As supposedly informed gatekeepers, we sadly earthbound Santas are reduced to scouring the back pages of gaming review sites and magazines, trying to evaluate whether the tot at home is ready for Big Bird's Egg Hunt or Bayonetta. Luckily, The New York Times is here to help. In a recent article provokingly titled 'Ten Games to Cross off Your Child's Gift List,' the NYT names its list of big bads — the video games so foul, so gruesome, so perverse that we'd recommend you buy them immediately — for yourself. Alternatively, if you need gift ideas for the surly, pale teenager in your home whose body contains more plastic then your average d20, this is the newspaper clipping to stuff in your pocket. In other words, if you need a list like this to understand what games to not stuff little Johnny's stocking with this holiday season, you've got larger issues you should concern yourself with. We'd suggest picking up an auto-shotty and taking a few rounds against the horde — it's a wonderful stress relief and you're probably going to need it."

Simplicity does not precede complexity, but follows it.