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Comment Not the worst thing to plug into a USB port (Score 1) 242

If you have physical access to a machine, you can do pretty much whatever you want to it.

If someone is planning to leave theses around to destroy computers then they could do a lot more damage with an infected USB drive - to anyone idiotic enough to plug in an unknown usb device.

If you want to maximize damage, an ounce of C4 in a drive will to a lot more damage. Thermite would be more spectacular.

I don't get it. You spend $150 for a device that will make a computer fail in a boring way.

Comment Re:How or Why: I Don't Care! (Score 1) 477

Cheaper and easier to test on earth. If you replace the copper with a superconducting cavity, the circulation power will go up by about a factor of a million. No problem at all seeing the thrust then.

I could do it for a couple million $ - we have the RF and superconducting cavity equipment. We are well set up to do the experiment.

The problem is that science money is limited. If someone wants to fund me, I'd be very happy, but there are a lot of other groups competing for those same funding dollars.

If someone can get the funding, or convince the funding agencies to switch their money to this, I'll do it. I wouldn't recommend it though - I think the odds of finding something are exceptionally small, and the money is better spent on other projects.

Comment Re:If confirmed, does this make it realistic? (Score 1) 477

It is possible to do a better experiment. With a superconducting cavity, you can get probably 10^6X the circulating power, and (based on their surprising linear slow slope of thurst vs power) a very large thrust.

This is a moderately expensive experiment (few million $), but would be very definitive. Lots of labs, including mine could do this.

Comment Re:If confirmed, does this make it realistic? (Score 1) 477

If relativity is correct, then producing more thrust per power than a photon drive without any exhaust can be used (in principal) to to build a perpetual motion machine. Basically this device claims to violate conservation of 4-momentum, so in the correct frame that is violation of conservation of energy.

If it is possible to create thrust against some sort of background (zero point energy, aether etc), that also violates special relativity by providing a unique reference frame (or violates conservation of energy if it doesn't).

Of course special relativity could be wrong - but it has been tested on scales from quarks to galaxies to black holes. This experiment is not unusual - they are at modest electric fields, length scales and frequencies. There is no reason to expect that after all the tests done on relativity it would be violated by using a special shaped box. Its like the idea that you can build a perpetual motion machine from a special shaped linkage and gears.

I may not be a "top" scientist, whatever that is, but I'm a professional physicist, and have discussed this with colleagues and we all agree that this can't be true without a complete re-write of physics as we know it, We also agree that its a very difficult experiment and that there are a lot of ways that they could have gotten the wrong answer from the experiment.

Comment We can test it if you like (Score 1) 711

We have 100MW RF sources at SLAC. Should give about a million times the force they see, or several newtons - easy to see. No mucking about with careful torsion balances - this is enough to see with a bathroom scale. I'm happy to do the test if someone wants to fund it.

It is exceptionally unlikely to work. The frequencies / field levels are not at all unusual. The existing experiments very difficult to get correct. Its difficult to believe that a violation of conservation of momentum wouldn't have been seen in the wide rage of experiments done in E&M.

Comment Re:Capitalism is killing science. (Score 1) 116

The issue isn't the scientist's salary, its funding for experiments. I work in a national lab which is a somewhat different environment, but there are some similarities. I can only work on and buy hardware for approved funded projects. The approval process is very slow, and the entire system is not set up to let scientists pursue interesting things as they develop.

Comment Re:Just curious... (Score 1) 232

Its interesting. In principal we could detect the sun's wobble but looking at Doppler shifts to distant objects. The problem with planet 9 is that the orbital period is so long that it would take too long to get a data set.

I don't know if anyone has measured the solar system wobble on shorter timescales. The information is probably already in planetary searches.

Comment Re:AnonCow (Score 2) 163

I understand, but I think the risk is that it becomes too easy to use these non-lethal (but very painful) devices when the police are not in any real danger. They could become the quick solution to too many problems. Eventually they might also have lethal weapons.

I think that one of the keys to reducing police brutality is a better connection to the people that they are supposed to be serving, and I think drones weaken that connection.

Comment Concept isn't new, but is the technology (Score 1) 88

There have been flying cars and vertical takeoff aircraft for decades now. The issues have always been engineering practicality. Carrying capacity, efficiency, range etc. The question is whether they have found a way to fix the technical issues that lead to these problems.

All electric may wind up cheaper, but the energy storage is even lower than for gasoline, so the weight problem becomes worse.

Vertical takeoff helps in some ways, but tends to lead to less efficient aerodynamics in cruise, and requires even more energy storage.

Very large single props are the most efficient (to reduce then number of tip vorticies), but lead to a helicopter like design. That leads to perhaps the most serious question - how is this better at flying than a helicopter? Helicopters are already very energy inefficient .

Comment Do cell recordings actually hurt sales? (Score 1) 552

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.

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