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Comment Re:Wait! I just remembered the memory man. (Score 2) 190

I turn on my phone's GPS to use an on-line mapping tool only rarely, such as when I'm visiting an unfamiliar city. Otherwise, I check a mapping service beforehand, memorize any key specifics, and off we go!

The upside: I'm always looking at the road and can avoid the idiots who aren't.

Comment Re:Time Crystal == Oscillator? (Score 1) 129

Ah, no. A stable oscillator can be easily constructed that fully resists changes in input (power supply) voltage. Your $5 quartz watch has one. From that perspective I really only see a difference being one of scale: this is a first only because it has been done on an atomic level.

And now that I happened to use the word "atomic", that makes me question: what's the difference between this and the cesium oscillator in an atomic clock?

Comment Time Crystal == Oscillator? (Score 5, Interesting) 129

I read the linked article (which is a summary of the real report). It's not my field.

How is what they describe anything other than just a stable oscillator? It consumes energy, since to run it requires regular (although perhaps not periodic?) pulses of light.

How is this different from a macroscopic tuned circuit that also resists changes in driving force, and oscillates at a stable frequency? Because it's made with a handful of atoms instead of gazoober electrons streaming around a circuit? I'm (not intentionally) being snarky -- I'm curious because by the article the physicists are peeing all over themselves in excitement, so I'm guessing they think there's something to this that I don't see.

Comment Re: Declining fields and Pole Reversals. . (Score 1) 118

So the supposition is that kilns have been found with pots inside, we can demonstrate that the pots have been left undisturbed since the start of their last firing many thousands of years ago so you can judge the orientation of the earth's field at the time of cooling, and, moreover, we know the kilns haven't been moved either?

Color me skeptical.

Note that the article talks about intensity not orientation. Intensity, I understand. Orientation seems implausible with this method.

Comment Re:Alternative Explanation (Score 2) 118

Multiple samples from independent sources and locations help mitigate those concerns, along with a slowly-varying time course of the field strength.

What manufacturing circumstances would change the strength of magnetization for ferrous inclusions in cooling pottery that would be present before, say, 0 AD to pick a convenient, arbitrary and approximately relevant threshold?

Comment Re:Declining fields and Pole Reversals. . (Score 1) 118

Hmm ... How are you going to determine field orientation at time of cooling below the Curie temperature for pottery? Wouldn't that require knowing the physical orientation of the item when it was being cooled after firing? Am I missing something, like there's a universal point-to-the-east orientation that all pottery is placed in when cooling?

I can see making a good guess for geological structures, but pottery?

Comment Re:The published article (Score 3, Informative) 218

The subtitle of the article makes it pretty clear that the handheld market is not what is being targeted here:

It might be an ideal form of energy storage for solar and wind power.

It's intended for fixed-location installations where physical volume isn't such a concern, so energy density, while important, doesn't matter as much. The same niche is currently occupied by the nickel-iron battery that was recently mentioned in another /. article that I can't put my typing fingers on right at the moment. Same issues there: high reliability and lifetime, but (comparatively) poor energy density suggests power-smoothing for solar or wind would be an ideal application.

Comment Pilots, not drivers (Score 1) 123

Here's the thing, quick and simple: Uber is not known for it's warm feelings toward its employees/contractors (depending on which side of the law you sit on). Driving a four-wheeled vehicle on the ground is simple enough that you can do it while seriously impaired without too much risk. Not so with something flying through the air. Pilots are not the same as the semi-employable edge of society that Uber is famous for employing/contracting (yes, I'm being intentionally inflammatory here).

Anyone, but anyone, can drive a car. Not everyone has the situational awareness to fly you through the air, and the vast majority of Uber drivers I've had would not pass even a low-bar flight test. How are they going to surmount the barrier that getting a pilot's license requires? Are they going to attempt to establish a new class of licence in the eyes of the FAA? Good luck with that. Engineering is one thing. Fighting government in 50 states plus the feds, now that's something entirely different. Finding talented people to pilot these things for bottom-of-the-bucket wages, well, that's crazy impossible.

Comment Failure point (Score 1) 49

The soft helmets are a cool idea. But when they're unzipped, as you can see in the many photos with the helmets at that pose, there's a lot of stress at the zipper. That's going to be a failure point, just like it is on your luggage. I'm surprised that there isn't a better solution for that.

That said, it took me all of 10 seconds to see that, and the folks at Boeing aren't idiots, so I hope they have tested the hinging of their zippers!

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