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MIT's Ted Postol Presents More Evidence On Iron Dome Failures

Normal_Deviate What he actually said... (344 comments)

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.


Forests Around Chernobyl Aren't Decaying Properly

Normal_Deviate Re:Probably bad reporting and hyped abstract (167 comments)

Hear hear. The truth is we cannot know the truth about politicized subjects unless we are directly involved. This problem wipes out whole fields of potential science, which is costly, annoying, and important to admit when formulating policy.

about 4 months ago

NASA-Funded Study Investigates Collapse of Industrial Civilization

Normal_Deviate Re:Reminds me of Control Theory (401 comments)

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.

about 4 months ago

Study Suggests Violent Video Games May Make Teens Less Violent

Normal_Deviate We already did this experment with porn (120 comments)

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.

about a year ago

Quantum Teleportation Sends Information 143 Kilometers

Normal_Deviate Re:If I recall..... (333 comments)

You seem to be saying there is no such thing as interference fringes.

about 2 years ago

Quantum Teleportation Sends Information 143 Kilometers

Normal_Deviate Re:If I recall..... (333 comments)

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.

about 2 years ago

Quantum Entanglement of Macroscopic Diamonds

Normal_Deviate Can we detect wavefunction collapse, or not? (160 comments)

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?

more than 2 years ago

Extremists Warn South Park Creators Over Muhammad In a Bear Suit

Normal_Deviate Re:You are clueless if you claim such a thing (1131 comments)

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.

more than 4 years ago

Wikileaks Releases Video of Journalist Killings

Normal_Deviate Re:How are we supposed to understand this? (1671 comments)

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.

more than 4 years ago

Tiny Cube Drags Space Debris From Orbit

Normal_Deviate Is this really a net gain? (77 comments)

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.

more than 4 years ago

Colliding Particles Can Make Black Holes After All

Normal_Deviate Re:Proved conclusively? (269 comments)

"Computer model proved conclusively...." No further reading necessary.

more than 4 years ago

The LHC, the Higgs Boson, and the Chicago Cubs

Normal_Deviate The wacky theory is testable (194 comments)

The guys who proposed the wacky theory did in fact suggest a test, and quite an interesting one. The critic who wrote TFA apparently missed it when he "skimmed" the papers he publicly ridiculed.

The idea is to conduct some random event, say 1,000 coin tosses, and pre-commit to cancel the LHC if we observe a ridiculous outcome, like 1,000 heads in a row.

more than 4 years ago

Why AT&T Should Dump the iPhone's Unlimited Data Plan

Normal_Deviate Re:Tragedy of the commons AGAIN (501 comments)

You pay a lot for the first byte. Every subsequent byte is the free commons.

more than 4 years ago

Why AT&T Should Dump the iPhone's Unlimited Data Plan

Normal_Deviate Tragedy of the commons AGAIN (501 comments)

How many times must we repeat this lesson? EVERYTHING that is free gets overused, or pissed on. Even air. EVEN AIR. There are no exceptions. NO EXCEPTIONS.

Don't make me say this again.

more than 4 years ago

Cellphones Increasingly Used As Evidence In Court

Normal_Deviate It is worth saying again (232 comments)

Privacy is doomed. The march of technology can be slowed, but not stopped. Eventually this will give us a world without theft. The trick is keep it from also giving us a world without fun. That means getting rid of most of our laws, not just nibbling around the edges trying to make it hard to enforce them.

No, I don't know how to achieve that goal, short of re-wiring some brains.

about 5 years ago

Mystery of the Missing Sunspots, Solved?

Normal_Deviate This is not an explanation (99 comments)

So solar output was correlated with sunspots. Now it is also correlated with a subsurface current. A step forward, but it is a bit premature to use the word "explain."

On a different not, how depressing that I have been pushed into resenting several forms of science. When I saw the headline, my first thought was, "Crap. More data to cherry pick to justify central control over individuals." And I say this as someone who has actually published in peer reviewed journals. Gloom.

more than 5 years ago

String Theory Predicts Behavior of Superfluids

Normal_Deviate Re:It's the math, stupid (348 comments)

Parent post is insightful. If a model is flexible enough, it can fit any data.

more than 5 years ago

String Theory Predicts Behavior of Superfluids

Normal_Deviate Explaining is not predicting (348 comments)

The main criticism of string theory is that it is too flexible. It can be contorted to generate any prediction, so it predicts nothing. This problem is not unique to physics; I saw it in economics too. Add more parameters to your model and you can fit historical data better, but your predictions of the future get worse. TFA seems to be just a string of examples of contorting string theory to fit past experimental results.

more than 5 years ago

Doctors Silencing Online Patient Reviews Via Contract

Normal_Deviate Re:First Amendment (324 comments)

What he said. In a world of villains and idiots, mischaracterizing constitutional liberties is not harmless.

more than 5 years ago


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