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Comment Re: This again? (Score 1) 480

The article talks about a model made by the NASA group assuming acceleration of virtual particles. It suggests greater than linear thrust to power ratios with increasing power, up to an optimum. Presumably the details would also depend on the type of device, frequency of microwave, etc.

Comment Re: This again? (Score 1) 480

That's pretty much what they're doing. NASA has been pretty quiet about the whole thing. The results have mainly been presented at conferences.

It's an extraordinary claim, but it does seem like they're working to provide extraordinary evidence. Also, the thrust claims aren't really very subtle. 1 N is pretty easy to measure, and the Chinese say they can get that using only 1 kW. It sounds like you could build one of these with a decent metal shop and a household microwave.

Comment Re:Can't wait to get this installed in my house (Score 1) 514

Perhaps you're not familiar with the term "inverter". Inverters are used to convert from DC to AC. The application we're talking about in this thread is charging a battery from the grid at off hours, then using it to power the house during peak. This requires AC (grid) to DC (battery) conversion, then DC (battery) to AC (household stuff) conversion. Plus AC to DC conversion by the device, but that's out of scope.

As I said in my post (with references), typical household inverter units get about 90% efficiency at maximum draw and very much poorer efficiency with low loads. The exact efficiency you get depends on your use case, but it is less than the optimum, so DC->AC loss sounds like a pretty reasonable estimate. 25% is probably low if you consider the full AC->DC->Battery->AC path since the Volt takes 20% loss just on the AC->DC->Battery part, and the DC-AC bit is max 90% efficient.

PS - telling someone to go Google something because they need the practice is rude. Then you went ahead and made unfounded assertions without the least bit of evidence. This makes you look like a rude idiot, regardless of whether you're right or not (you weren't).

Comment Re:Can't wait to get this installed in my house (Score 1) 514

I just read your post rudely telling someone to go google battery efficiency. Perhaps you should heed your own advice. Small household inverters might be around 90% efficient (10% loss) running near their peak output. If your setup allowed the inverter to idle or only supply a small amount of power (running your alarm clock at night), it could be very much worse than that. http://www.homepower.com/artic...

That's only one side. You've also go to convert the AC to DC. An average of 25% conversion loss doesn't sound too unreasonable (and the OP posted an IEEE reference to that effect). Unlike your completely unreferenced post.

Comment Re:false positives (Score 1) 174

You shouldn't be impressed by people who publish insignificant results. Insignificant doesn't mean "not true." It means inconclusive. You should be impressed by people who go the extra mile to turn their not significant results into meaningful limits on parameter estimates (setting limits on how big an effect could be). That's done a lot in physics but only occasionally in other fields.

The only reason for publishing inconclusive results is to allow somebody to incorporate them into a later meta-analysis, or to serve as pilot data for someone doing a power calculation to plan a larger experiment.

Comment Re:39/100 is the new passing grade. (Score 1) 174

What do you mean by "accept?"

When you publish in a journal what you're really saying is "hey, look what I did! What do you guys think?" The point of publishing your work is to tell people what you found so they can evaluate it and try to reproduce it themselves.

If you mean that people, both scientists and the layman, shouldn't believe something is true until it's reproduced? Absolutely that would be a good idea. Even better, wait until a good meta-analysis is performed.

Incidentally, the FDA generally requires at least two large, independent trials, both of which are significant, before a drug is approved.

Comment Weird way of looking at it (Score 1) 211

It seems like much less than 10% of working people would be qualified to do any given skilled non-managerial job. When most labor was unskilled you'd promote dirt-common unskilled employees to management if they demonstrated they had the moderately uncommon talent to manage. Now that most "labor" is actually highly skilled, you should get promoted from common manager to skilled worker if you demonstrate you have the rare talent to do that job. Managers should be lower-level employees who do the administrative tasks to free up skilled workers to concentrate on their valuable work.

Comment Re:Argentina outlaws Bitcoin in 3...2...1... (Score 1) 253

You're correct if the bitcoin is actually being used inside argentina (you'd have to replace that with dollars). But it doesn't seem to be. It's immediately exchanged for pesos. The argentinian exchange has to somehow buy pesos with bitcoin, and since argentinians aren't walking about the grocery store with BTC wallets the suggestion is that those pesos come from argentinians with savings who want to move their money out of the country. You could replace that chain of exchanges by simply matching up argentinians who do business with foreigners with argentinians who want to buy foreign currency.

Comment Re:/.er bitcoin comments are the best! (Score 1) 253

Somebody is always left holding the bag. In this case the bitcoins are held entirely by the exchanges so in aggregate they effectively hold the necessary bitcoins statically. If there's no arbitrage between them then movements in the value of bitcoin are shared equally among them. If the hypothetical rich argentinians are somehow unable to turn their bitcoins into us-dollars-in-the-us then they take the loss instead.

Comment Re:Argentina outlaws Bitcoin in 3...2...1... (Score 1) 253

Yeah. The interesting question is, why?

Someone suggested it's rich Argentinians who want to get their money out of Argentina. Sounds like there's a market for a US-dollars-located-in-the-US to pesos-located-in-argentina exchange business. That would replace at least two middlemen with just one and eliminate the risk of dealing with an unstable medium of exchange. There's really no reason to involve bitcoin at all, except to facilitate two separate exchanges skimming off a fee.

Comment Re:/.er bitcoin comments are the best! (Score 1) 253

I don't know anyone who holds a significant amount of currency, rich or poor. If you're poor you're probably not holding any more money in any form than you need to buy essentials for the next month. If you're better off you might have savings, but they'll be in a bank. If you're rich you have investments.

One of the reasons the rich keep getting richer is because the poor and middle class are willing to lend value (in work or money) to them for cheap or free.

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