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Comment Re:A little behind the times (Score 5, Informative) 315

* they did pretty much all of the things you would like to see (such as reversing the direction and making sure the thrust reverses).

* they seem to have done a thoughtful and careful job, including testing in vacuum.

So, I still think they are likely wrong, but this ups the ante. In my opinion, you can't just say "this is obviously wrong."

Sure I can. Was the apparatus temperature controlled during the vacuum test? Was it tested in all orientations (not just backwards) to remove any gyroscopic weirdness from the rotation of the earth (think Michelson-Morley experiment). Was there EM coupling between the cavity, the torsion balance, and the chamber that could manifest as an anomalous torque, not thrust (that is, did they just make a big brushless motor)? Does the instrument register a thrust when the cavity is radiating but is bolted to the chamber floor and not the balance? Is there no thrust when it's oriented orthogonally? Does it still work if the power supply is electrically isolated from the vacuum chamber without a common return (ie did they build an electron gun)?

Comment Re:So (Score 1) 160

I remember a study making the news in the 90's comparing men and women's brain activity while doing tasks that require 3d reasoning. It was kind of a similar result: men and women would score about the same on the task, but the women's brains lit up like a Christmas tree while the men's brains had fairly localized activity.

Comment Re:Repetitive (broken) OS abandonment (Score 4, Informative) 240

It's a two cultures problem in IT. The vast majority of Microsoft's, or Apples, or Oracles, or whoever's customers use their OS on laptops, workstations, or servers, where the consequences of bugs are fairly well approximated by "nuisance". The other culture of computer software customers are folks who use computers handle large amounts of money and control moving machinery (power plants, drones, etc), where the consequences of bugs and unintended features start at "oh shit, we've lost millions of dollars" to "oh shit, the crane dropped its load 200ft" up through "oh God, the power plant has exploded!" People in the second camp have a healthy suspicion of getting the latest and greatest upgrade from companies run by and for people in the first camp. And that dichotomy is why most embedded OS's come with source code that you get to debug yourself if it doesn't quite work for your application (VxWorks, QNX, Windows Embedded, RTLinux, etc).

Comment Re:Putting people in an autonomous car (Score 1) 301

Well, if the cars only went on special roads, you'd be right, and just like the elevator, the people who are responsible for maintaining the roads are responsible for any accidents. But normal elevators don't pop off their rails and walk you to some arbitrary location on your chosen floor. My point is that autonomous cars should be considered like an airplane with a super-duper autopilot. Sure, the pilot just pushes a button and the plane does its thing, but the pilot is still responsible for a visual inspection and preflight check every single time.

Comment Re:Putting people in an autonomous car (Score 2) 301

Well, yes and no. If you're going to let autonomous cars drive in the same environments where you let people drive cars right now, as opposed to separated lanes on a few specially designed and maintained roads, the human ultimately should be responsible. Like if the car crashes because you didn't clean the bird-shit off the camera, or you didn't notice that the radar antenna in the front got dinged by a shopping cart and is about to fall off, it is your fault when it falls off and the car crashes.

Comment Re:diesel-electric? (Score 1) 160

Jet engines themselves are a step back from high bypass turbofans and turboprops. One of the rules of thumb for aircraft engines is that a bigger fan spinning slower is more effecient than a smaller fan spinning way faster. But the the prospect of having basically all fan driven electrically without an obstruction from compressor, fuel handling, etc may swing the balance in favor of diesel electric (ie one turboshaft driving a generator running the fans) in some cases.

Comment Re:Flight time 1 hour (Score 5, Interesting) 160

Which is why battery-powered planes are stupid. But not necessarily electric propulsion. If you can actually fly an electric engine, you can get experience and improve on it, so that if and when you come up with a better way of providing electrical power (electrochemical fuel cells, fission reactor, Mr. Fusion, very long tether, microwave death ray), you will be able to mate it to a mature technology. I say kudos!

Comment Sad, and not black and white either (Score 4, Insightful) 351

The metaphorical White Man has a heavy burden here. Reach out to the savages, and there are adverse consequences, suffering, death, and loss of traditions going back millennia. Stay away, and people who should be your fellow human beings are cut off from the fruits of civilization, and are treated like livestock whose habitat must be delineated and (un)managed to keep their numbers healthy so that more children can be born into a life where their greatest aspiration can be to live just like their grandfathers going back tens of thousands of years.

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