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Comment Re:How is the no fly list legal? (Score 1) 286

Yes, they have a bunch of guys with guns.

Oh, you mean "should" they impose penalties without due process.....

Americans sadly seem willing to trade their hard won rights and freedoms for a little safety. Certainly not the way I'd vote (assuming there was a candidate who didn't support this), but one of the disadvantages of a democracy is that sometimes the will of the majority isn't very clever.

Comment Re:hm... (Score 1) 143

No, only the people investing in this are idiots, the ones collecting the money are quite clever.

  Its really difficult to imagine that this is cheaper per power output than a conventional generator. the balloon is big, fragile and probably limited lifetime. Subject to weather, ice, lightning, etc. The supports are not at all trivial - picture holding a balloon on a windy day - the wind X tether will tend to push the balloon downwards - this will significantly limit the max wind speed where this can be used. At the same time the tethers need to resist the torque of the turbine - or it needs counter-rotating blades which are less efficient and more complex. You need a large clear area or if the balloon deflates it could land on something doing damage. If multiple balloons are close to each other, a very stiff multi-point support is needed or they will collide if the winds shift. That still doesn't solve the strong wind problem listed above, so the tethers need to have a system to reel in the balloons when bad weather is predicted. The higher wind speed is nice, but its difficult to imagine building one of these that is anywhere near the scale of a large modern windmill.

This is just a dumb idea.

There are very strong winds very high up (30,000'), but the long tethers cause all sorts of problems - and you need a huge clear area around the supports. (imaging dropping 20 kilometers of ultra-strong cable across a city.........(buses, trains etc.....)

Comment Re:Not trying to steer the car this car off the ro (Score 1) 367

In that case this is MUCH more serious. Sexting has sometimes been considered child pornography, a FELONY offense. Pressuring an underage person to reveal incriminating information that has the potential to send her to prison and ruin her life should be illegal.

I don't know the law on questioning minors. Can the police question a minor without parental consent, and without a miranda warning? If so, this seems like a big weakness in our legal system. (since one cannot reasonably assume a minor is educated in their legal rights).

Comment Re:Customer paying for bandwidth helps (Score 1) 466

Yes, I think it only makes sense if the total company revenue is roughly constant after the change. Low data users would end up paying less, high users would pay more. It would even allow a bit more range in services offered.

It might make sense to have different data rates at different times. Then it would make sense for torrents to run at low-use times of day.

Comment Re: Customer paying for bandwidth helps roxy (Score 1) 466

This is the same sort of problem we have with gas stations - how do you know you got 10 gallons, not 9.5, in a business with very small margins. Spot checks by an independent agency and very large fines would help. Maybe some company will make a router that is certified and will keep track. If you think you are being ripped off ,you can use one and find out - again this needs to be paired with large fines.

Comment Customer paying for bandwidth helps (Score 1) 466

I know its unpopular but this situation is much improved if the customers paid by the GB downloaded. Then Comacst, ATT, etc would welcome new sources of bandwidth (like netflix or small startups) because they would get to sell more GB of data to the end users.

A monthly connect fee + a $/GB fee seems to solve a lot of this. It seems to me the root cause of the problem is that if customers don't pay for bandwidth, the ISPs have a financial motivation to ship less data not more.

Comment Re:Recycle! (Score 1) 323

Sounds very familiar - my organization is going this direction. I'm curious though, do you know of specific examples where this has failed badly? Workers tend to argue that laying off old experienced workers is a bad plan, but one could argue that they are just acting in their own self-interest.

We recently lost (due to an unexpected death), a person who was believed to be absolutely irreplaceable. To my astonishment things have continued to operate.

I'd like to believe that experience is very difficult to replace, but is it really true?

Comment Re:Next up: a direct detection (Score 4, Informative) 269

It would not be possible to detect gravity waves (or anything else) from a source inside a black hole. Here we are talking about gravity waves created when two black holes interact.

Imagine to non-black holes - say neutron stars colliding (boom!). As they collide the gravitational field around them varies rapidly ( changes from 2 sources to a single source). Those variations send "ripples' (gravity waves) through space. The ripples aren't just from inside of the neutron stars, but from the fields which extend outside. If you now collide black holes, the same thing happens, gravity (and curvature of space) near the black holes changes radically as they collide and some of that is emitted as gravity waves.

The above is of course a hand-wave. The *real* answer is that you can simulate the Einstein field equations as the black holes collide, and they show the radiation of gravitational wave.

Comment Cargo cult? (Score 1) 48

Really? We are going to spend money building a launch pad for a rocket that will never fly again, rather than on rockets that will? I'd be a lot more tolerant of this sort of thing if we had something now that replaced the shuttle.

How is the plan to pay the Russians to put our astronauts in space looking now.....

Comment Re:LIGO is a money pit (Score 3, Interesting) 70

I was on a LIGO review committed years ago (and worked on the precursor to the project many years before that). At the time of the review, LIGO had worked with a vendor to produce extremely low loss coatings. Based on that technology that vendor was able to move into the (at that time) rapidly expanding telecom optics business - and actually refused to make the parts LIGO needed) because the technology was more valuable to them for telecom. LIGO really was driving the optics business back then.

I believe there have also been spinoffs from their stabilization and vibration isolation work, and possibly from their ultra- stable frequency laser work (Maybe someone from the project will respond.... Stan???).

The value of basic physics like verifying, or disproving general relativity is of course much more difficult to measure. What is the value of understanding the large scale structure of the universe, or physics at very high energies? I don't know the coin to use to measure that. There was a time when number theory, quantum mechanics and relativity all seemed pretty esoteric and useless. That doesn't mean that all basic science is valuable, but there is no way to know in advance what is.

Comment Re:Please explain (Score 2) 70

You can't increase and decrease mass - so no monopole gravity waves.

You can't move the center of mass (conservation of momentum) so no vector gravity waves.

You can change the distribution (imagine two masses moving closer and further apart), and this generate tensor (spin 2) gravity waves.

The coupling is VERY small - so the energy radiated is tiny unless you are dealing with near black-hole conditions.

Comment Re:LIGO is a money pit (Score 2) 70

A heavy object would bend gravity waves - they propagate the same way light does.

My memory is that there are 2 polarizations of gravity waves (sort of the way there are 2 polarizations of light), but they are carried by spin-2 particles not spin-1 so the polarizations look somewhat different. They look vaguely like sheer waves, I do not believe there is an equivalent of pressure waves in standard general relativity.

Comment Re:LIGO is a money pit (Score 1) 70

By analogy, a black hole is a distortion in space time, but it can bend light. The curved surface of the earth can be measured entirely by measuring the distance between points along the surface.

I believe you are right that you could construct space=time distortions that would not affect the travel time of light, but you can also construct those that do - and gravity wave distortions do change the travel time.

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