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Comment Re:How are mobile phones legal then? (Score 1) 64

As the AC implies, that's not interference from bad or unshielded electronics in the mobile (or it shouldn't be).

An ideal mobile transmits only what it's supposed to, on the correct RF channels to communicate, and nothing else.
Like all devices there will be other emissions, but let's assume it's very well made and effectively perfect.

The sound on the speakers is because the speaker circuit is effectively an RF receiver, converting those high frequencies to audio. They actually demodulate the signal - unintentionally. See http://en.wikipedia.org/wiki/Electromagnetic_interference#RF_immunity_and_testing

If the speaker circuit is made well enough, it won't do this.

Comment Re:No comments, then a flood of experts (Score 5, Informative) 238

Let me 'splain. No. There is too much. Let me sum up.

So, when you collide high-energy particles, you get lots of outgoing particles. Sometimes more, sometimes fewer. One thing that you can do to study the outgoing particles is to look at all pairs of tracks in the event (the combinatorics get very large, but you can still do it), and make a histogram of how close together all the pairs were. When you do this, you find that there is a proliferation of tracks that are very close to one another. This is because the outgoing particles tend to come in clusters (we call them "jets"), all moving in approximately the same direction. This happens, more or less, because if you get one outgoing particle with very high energy, but it is an unstable particle, its decay products will tend to be moving in roughly the same direction as the original particle.

Now, you can also do something slightly more sophisticated: instead of just looking at the angle (in any direction) between two tracks, you can use spherical coordinates, and look separately at the angular distance *around* the beamline (azimuth / phi) and the angular distance *from* the beamline (polar angle / theta) (although we actually convert the polar angle into a strange quantity called "pseudorapidity" instead ... this is unimportant for this discussion). When you do that, if you look at events with relatively few outgoing tracks (<35), you see exactly what you expect: an proliferation of tracks that are close in both azimuth and polar angle -- jets again.

On the other hand, if you look at events with lots of outgoing tracks (>= 110), you still see the excess of tracks that are close in both azimuth and polar angle from jets, but you also see a "ridge" -- an excess of tracks that have almost exactly the same azimuth as one another, but have very different polar angles. This is unexpected, and unexpected results == SCIENCE!

So, we expect particles to appear tightly clustered together, but what we see (in some events) is more like a flat spray of particles that goes from one beamline to the other, but is very tightly constrained in one azimuthal slice.

Terrible analogy: We expect cities to occupy a roughly circular area of the earth's surface -- tightly constrained in both latitude (polar angle) and longitude (azimuth). This is like finding a planet that has a city that stretches from pole to pole, but only along a single meridian -- tightly constrained in longitude but totally unconstrained in latitude. It's just plain weird.

Comment Re:so what if they're minors? (Score 2) 423

Yes, and every thread will be investigated by the Secret Service.

I don't think that this guy's blog will have any impact on Secret Service investigations. If they felt there was a sufficient threat to merit investigation in any particular case, then they are more than able to discover the information this guy has uncovered (and more!) without his help. If they felt that some other particular case was not worthy of investigation, then this guy's blog will not convince them to investigate. The blog is a complete non-factor as regards the Secret Service.

Comment Re:Practical in some, but not all, applications. (Score 2) 490

Self-driving vehicles may make EVs much more practical. Imagine, if you will, a world in which car ownership is rare for the simple reason that you can rent a self-driving vehicle of nearly any configuration from a fleet. This is markedly cheaper than renting a car now, because, when you are not using the vehicle, somebody else is (contrast with flying for a business trip and renting a car to go from airport to hotel to office to airport -- most of the time the car is sitting idle).

It also removes the "second vehicle" economics from the equation. When you need a short distance trip with little to no cargo (say a shopping trip or a commute), you get a subsubcompact EV. If you need a slightly longer trip, then you get a hybrid or gas car. If you need cargo or towing, you get an appropriately configured truck or SUV. Etc.

Suddenly, you can always use a vehicle that is appropriate to your immediate needs without every household owning many different cars (commute EV for her, commute EV for him, family car, old beater for the 16yo, SUV for the boat, whatever else you might think of).

Of course, self-driving tech is also still a few years off. It will be interesting to see whether EV tech or self-driving tech can advance fast enough to make non-gas cars feasible for a substantial portion of driving before rising gas prices cause economic havoc...

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