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Comment Re:Blimey (Score 1) 438 438

I had to look deeper to see that you are correct. There _have_ been several NASA published designs using microwaves or other EM for ordinary thrust, I'm afraid I thought the original article concerned one of those.

On review, as I mentioned elsewhere, I'll bet that this is really a "Dean Drive". The Dean Drive never worked well outside the designer's workshop, was never tested properly with a basic "pendulum" test, and seems to have been a basic "oscillation thruster": it interacted with the floor under it to provide net thrust. That would mean the system is not really "sealed", it's interacting with its environment in some subtle way.

From the description at, I'd guess EM interaction with the walls of the stainless steel vacuum chamber. And one of hte people I'd want to review the experiment would be James Randi, who's been helping debunk "mysterious mental force" claims for decades, and has a professional magician's eye for misdirection and sleight of hand.

Comment Re:The argument is "leaky" at best too (Score 1) 189 189

> evolution does not consider risks and benefits, changes are random

Interestingly, not all changes are random. There are some fascinating changes in DNA triggered by environment, many of them studied as "epigenetics". And there are certainly changes in organisms that are defensive responses to environment. The darkening of skin under sunlight is a classic example. Evolution occurs at _many_ levels. These include environmental, biological, behavioral, cultural.

Comment Re:Not the best summary... (Score 5, Insightful) 189 189

> The only group that is really helped by other people's vaccinations is a small percentage of the population that cannot get vaccinated.

You obviously don't remember polio. I do. You apparently also don't remember when the flu killed so many people in winter, and fail to understand how modern cities and especially air traffic make pandemics far more likely and far more dangerous.

Comment The Dean Drive is back (Score 2) 438 438

There was a similar set of claims roughly 60 years ago for the "Dean Drive" a "reactionless drive" that did not seem to use propellant. To casual review, and letting it push your hand, it seemed to work, and a great campaign for research and to ignore the sceptics of the time was headed by John W. Campbell, the editor of Analog magazine. Analog was, and remains, a science fiction magazine specializing in hard science and science fiction based on it, and it had many real scientists as readers and contributors, so the Dean Drive received quite a lot of attention.

The Dean Drive has since been pretty thoroughly debunked as an "oscillation thruster", a device that relies on tuned "slipping" on the floor it rests on to creep forward and even to provide a modest thrust, _pushing against the floor_. The designer was never willing to allow a full "pendulum" test, or careful testing outside of his own workshop, and there seem to be dozens more of similarly patented "reactonless drives". The ones that work at all also seem to be "isicllation thrusters", pushing against the floor or the mehanism in which they are mounted.

Comment Re:Blimey (Score 1) 438 438

> As an added added bonus, such a drive would accelerate faster at a given thrust, because of the absence of reaction mass.

If only they didn't require an actual motor, or storage system for the energy for the microwaves. Since the maximum _chemical_ energy available in batteries is quite close to that of a good chemical propellant, it's only a big benefit if the energy for it comes from elsewhere, such as solar cells or a quite large nuclear power source. And if you have low mass space based solar cells, you can use either a solar _sail_ based system, or a transmission base to propel target spacecraft with a larger, more stable microwave source.

Comment Re:Safety (Score 1) 63 63

I very much agree with you. I'd not expect immediate, dangerous coupling from a relatively low intensity coupling such as a recharger might product, even if someone slept with such a device under their pillow and wore loop earrings.

It was the reasoning from viperidsenz that because MRI is safe, inductive recharging is safe that I meant to call into question. MRI, misused or accidentally mishandled, can cause injury and death. The scanners devices are not a good starting point for comparison of safety.

Comment Re:This is the WRONG focus (Score 1) 63 63

> It is easy enough to plug it in.

It's also quite awkward and destructive to the connector if any mistakes happen, and lugging around the cabling is awkward. It's hardly a new idea, "" has been selling such stations for years.

Unfortunately, the customized charging case you have to keep the phone in for Powermat to work are quite expensive and make the phones unwieldy.

Comment Re:Safety (Score 1) 63 63

Thank you for pointing out that a small loop may not cause injury. A casual look at published guidelines shows that they say to remove _all_ metal, and some metal may be safe if designed carefully. But some guidelines accept that wedding rings, in particular, may be impossible to remove without cutting them and accept the modest risk. I'm looking particularly at this as an example:


So you've raised a very good point, thank you for the refinement. In turn, I'll point out that not all patients in an MRI are conscious, and that not all loops are worn on the hand. There is a particular case, described at, where a man with a very serious head injury had a "magnetic resonance safe" pressure monitor implanted in his head. It coupled to the MRI, and the tip melted in his brain.

Comment Re:How about where you can find electric outlets? (Score 1) 40 40

If you rely on your phone for work messages or reaching loved ones during travel, here are some hard-learned suggestions.

1) Don't leave the house thinking "I've got 30%, that's plenty until I can find a charger!".
2) No video or audio except when it's plugged into power or someone is paying you for it, whether it is your workplace or your family's good will.
3) Use an older phone with simpler features. Real work _does not need_ large screens or high scores on cell phone games.
4) If you get bored, bring or get a book. Even a local daily newspaper can provide fascinating local politics and color to share with business contacts while traveling.
5) Carry a real battery, one that is as large as your phone. Numerous batteries with enough charge to recharge multiple cell phones work very well at long meetings, and it makes you seem well prepared if you can recharge both your own phone and the other person stuck there all day. They're also invaluable on long plane trips, commutes, or drives home when you've had no chance to recharge your phone all day.

Comment Car electronics are safe like work IT systems (Score 5, Interesting) 158 158

Car electronics are safe like work IT systems are safe. No one competent would design the systems with a shared set of credentials, with an easily cracked master control system, with low security systems granted bus access and with privileged commands going over the common bus without protection, because we "trust the people we work with".

Unfortunately, this is rarely completely true in a large IT environment. There's often a set of vulnerabilities, which can be closed but require time and resources not allocated in the current quarter or even ever enabled. They're checked off on the security checklist, but the checklist is crafted to avoid the real problems, or personnel simply lie outright: this is at the core of many companies compliance with the FIPS guidelines. Those kinds of gaps help pay my salary: I often help close them and reduce the danger of them while they're being fixed.

For car systems, there are various "buses" in use now. A casual search shows more than 10 distinct "vehicle bus" standards in use, and trying to secure and reliably use all of them consistently and safely _in terms of security_ is barely feasible, much less likely in the high urgency car market. The components also have to be extremely robust, low quiescent power, and not too expensive per unit, which adds other limitations and slows closing known security or newly discovered security holes.

So I'm afraid that real security risks of the systems are to be expected. And they're quite unlikely to be fixed quickly when discovered, because it could involve replacing core components of the system and causing a _much_ higher rate of upgrade induced failures.

Comment Re:Safety (Score 3, Informative) 63 63

Unless you have a conducting loop in or around your body when it fires, such as a wedding ring, or a magnets in your body, such as are found in some medical electronics, or if you've got any accidentally embedded magnets such as those swallowed by children..

Or unless there is a bulky, conducting metal object in the room, such as an oxygen tank:

I'm not suggesting that a modest hom recharger will create such risks. But please, do not extrapolate armchair physics to assume you understand the real risks of a real electromechanical device without doing the research.

Comment Re:Belgian Science gone wrong? (Score 1) 58 58

It's generally not known to American students, no. The lack of direct US military involvement, and the slaughter of millions by wealth seeking remote nationals doesn't garner the same sympathy 100 years later as the genocide of a nation's own citizens that occurred in Nazi Germany and in their conquered territories, a genocide that American military forces became directly involved in stopping and witnessed directly. There are few people alive who remember it personally, but the availability of popular media and of film evidence lent the later genocide more visual and historical power.

You are in a maze of little twisting passages, all different.