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Comment Do cell recordings actually hurt sales? (Score 1) 548

A poor quality cell recording of a concert is nothing like the experience of actually being there. I'm not at all convinced that such recordings hurt sales, they might actually help them by acting like advertising. If a friend shows you a bouncy video of an awesome concert isn't it more likely to make you want to go to the next one?

There are some people who can't afford to go to concerts and will watch the videos instead - but the artist was never going to get money from those people anyway because they didn't have it in the first place.

Comment Re:EM Drive -v ION drive = 1st space robot wars (Score 2) 132

Anyone who wants to fund the experiment is of course free to do so. I'd advise against it though,. The EM drive claims to violate conservation of momenum (4-momentum if you are being picky), under conditions that are not in any way outside the range of typical experiments. The theory, at least as presented in the AIP advances doesn't make any sense at all. The experiments are tricky and easy to get wrong. (the thrust is tiny so forces on cables etc could easily distort the measurement).

I know the argument about long shots and Pascal's wager, but there are an infinite number of possible experiments, so trying random ones doesn't make sense.

An earth based measurement with a superconducting cavity (which would allow large fields with very small RF power), would probably be a better / cheaper test.

Comment Re:Complex Passwords (Score 1) 210

two factor authentication is great when done correctly, worse than useless when done poorly.

"security questions" are not 2 factor authentication. They are just low entropy passwords.

If 2 factor includes a device, then there needs to be some way to authenticate if that device is stolen when you are in a remote location. That of course also breaks the concept - but what is the alternative?

Bio-metrics can work if they can be made sufficiently reliable,

Comment Highly political (Score 2) 141

The world of next generation high energy physics machines is highly political. There are plans for LHC luminosity and energy upgrades. The long delayed ILC (international linear collider) project, proposed for Japan. Competing designs for a lower energy circular lepton collider (maybe China) to be upgraded to a very high energy hadron collider. Laser and beam driven plasma accelerators - neither anywhere near practical yet. CLIC, Muon collider, VLHC, etc.

There really are two issues: Is it worth ~10B$ to build the next generation high energy physics machine, and if it is, which of the many machines should be built. With machine development likely to take a generation, people on any project know that success of another will doom their machine.

Neither question is easy to answer. There is no clear way to measure the value of fundamental physics measurements. The likely technological value is zero, though spin-offs can be valuable.

To me personally, learning about the most basic structure of the universe from high energy physics, or astrophysics is valuable, even if it has no imaginable application. I view learning about the universe as one of the goals of civilization, not a means.

Comment Need to categorize drones (Score 1) 239

I think that very lightweight drones that do not represent a hazard including through aircraft ingestion only need to be regulated in terms of noise and privacy ordinances. As the size / hazard of the drones goes up, the regulations should be tighter. A drone the size of a manned aircraft should operate under the same regulations.

Comment Re:A law is only a law until it's proven wrong (Score 1) 248

Scientists spend lots of time trying to find ways in which our current understanding of physics is wrong. This is generally done by doing measurements that are in some way fundamentally new: new conditions, higher accuracy experiments, measuring new things. LHC looks at interactions at very high energy. Low temperature experiments look for unexpected effects at extremely low energies. Astrophysical measurements look at effects in very strong gravity, or very large distances.

Electromagnetism has been measured over an enormous range of scales. We see it a sub-atomic scales and extreme field strengths in particle collisions. We see it in very slowly changing, very low density fields like galactic magnetic fields. At SLAC we looked at high intensity fields at modest energies when we scattered gamma rays from high intensity lasers to look for (and found) nonlinear effects predicted by EM theory.

The problem with the EM drive is that there is nothing unusual about it. Its just a microwave cavity with modest fields at modest frequencies. These sorts of fields (and much stronger and weaker ones) are regularly used in a wide variety of experiments. If they use Maxwell's equations there can be no effect because the equations locally conserve momentum. There is no coupling to dark matter at this level, much more sensitive experiments have been done. There is no reason to think it will work. The measured thrust is very small, easily explained by a wide range of other normal effects including tilting of the apparatus as experimenters walked around the room.

Doing the experiment in space will not help. There are a lot of other forces at play - solar wind, light pressure, out-gassing. They would have to demonstrate a substantial velocity change (probably 100s of m/sec). which would required a lot of power for a long time .

Comment Don't trust the FBI's ability (Score 2) 367

Even if I trusted the FBI to only use the information for the public good and in accordance with the law, I don't trust their ability to secure the information. Whatever mechanism is provided to the FBI to access secured data risks being transferred to some non-trusted party.

One the most important lessons from Snowdon was that even the NSA cannot protect its own secrets. How can I possibly be convinced that the FBI will be able to do so? Will Llooyds insure them for say $1T against a data breech? Or how about in the event of a breech, the directory and the top 1000 managers are executed (regardless of their personal guilt)? Are they *that* sure? If they aren't that sure, then I'm not sure enough to trust them. Imagine the damage that could be done by a person or government with access to virtually all information in the US .

Comment Re:Interesting to quantify if possible (Score 1) 321

That is certainly true, but a different problem. Too many people will create resumes targeted at specific jobs in the hopes of getting an interview, even though they don't have even the basic skills required. I don't know if there is any statistical difference in how often women do this.

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