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Comment: The Oxford Electric Bell (Score 1) 403

The Wikipedia explains:

The Oxford Electric Bell or Clarendon Dry Pile is an experimental electric bell that was set up in 1840 and which has run almost continuously ever since, apart from occasional short interruptions caused by high humidity.

[...] The Oxford Electric Bell does not demonstrate perpetual motion. The bell will eventually stop when the dry piles have distributed their charges equally if the clapper does not wear out first.

Comment: Re:Of course, there's this (Score 2) 176

On one hand, oil is HEAVILY TAXED from the consumer ...

Which is ostensibly a use tax on roads and transportation infrastructure.

Would you prefer a more Socialist approach to funding transportation and have people who walk, or bicycle, or drive less, or use a more fuel efficient vehicle subsidize people who get the most direct benefit from the roads and bridges? Or would you prefer to let our transportation infrastructure crumble?

In addition, since exhaust from motor vehicles is a large contributor to air pollution, a tax on gasoline can be seen as compensation for the external costs of burning fossil fuels. Laissez-faire free markets are notoriously bad at dealing with externalities fairly or efficiently. The lack of a gasoline tax or too low of a gasoline tax would be in effect a huge subsidy for fossil fuels.

An example of the tremendous economic inefficiencies of subsidies through insufficient taxing of externalities was the near total destruction of light rail in the United States. The fuel tax for commercial buses did not adequately reflect the advantage given to buses over rail due to the road infrastructure provided by the government. This led to the downfall and destruction of most of the light rail in the United States even though it is extremely more efficient than using buses.

Comment: Re:This again? (Score 1) 480

by DrJimbo (#49601925) Attached to: New Test Supports NASA's Controversial EM Drive

All observed phenomena obey the laws of physics. By definition.

Bullshit. All correctly observed phenomena obey the laws of physics. Funny thing is that the vast majority of observations that apparently violate the laws of physics turn out to be incorrect.

The current case is a good example. NASA used 100 watts and measured a force of 50 microNewtons. You would need a force 20,000 times larger than that to levitate an apple. Unless you increase the efficiency of the effect by many orders of magnitude then, even if it exists at all, it has no practical application.

In these sorts of situations where experimentalists measure a very very small effect (the measurement made in China, which was not in a vacuum, was over 100 times larger) and there is no reasonable theoretical explanation for the effect and the effect contradicts the established laws of physics then the explanation is almost always experimental error.

Comment: Re:This is not a photon drive (Score 1) 480

by DrJimbo (#49598743) Attached to: New Test Supports NASA's Controversial EM Drive

Those conjectures are based on the author's explanations of the mechanism, which we already know to be largely bunk.

Bzzt. Wrong. Those conjectures were from from Paul March who is "an engineer at NASA Eagleworks". None of the authors are named March.

Compared to the actual momentum imparted by 1kW worth of photons, which is what current physics suggests would be the only source of momentum, the amount of force measured is much more significant. Hence, fairly efficient by comparison.

It is true that the small force that was measured was much greater than the even smaller force of a photon drive (hence my post and the quote therein) but it was still very small compared to the energy that was used and was orders of magnitude smaller (per kilowatt) than what March said would be needed for a practical device.

The NASA tests measured the same force in both vacuum and non-vacuum environments. Any results from China are suspect since falsification is much more rampant there.

I agree that the result from China should not be trusted. On the other hand, the NASA results measured a significantly smaller force per kilowatt than what was measured in China. The article implies the NASA experiments measured 50 microNewtons with a 100 watt input. Or 2 Megawatts per Newton. So you would need 2 Megawatts of power to levitate an apple:

The simulation for the 100 Watts input power (as used in the latest tests at NASA) predicted only ~50 microNewtons (in agreement with the experiments) [...]

I trust the extrapolations of the computer model even less than I trust the experimental results from China. I think it is overly optimistic to pin one's hopes of a viable method of propulsion on a measurement of a force of 50 microNewtons from a device that is putting out 100 watts. Extraordinary claims require extraordinary evidence. I see no signs of such evidence here. I think the laws of physics as we know them still hold and they experimentalists made a mistake, just like with Pons and Fleischmann (even though their claims did not violate basic laws of physics like these so-called results do).

Comment: Re:This is not a photon drive (Score 1) 480

by DrJimbo (#49597743) Attached to: New Test Supports NASA's Controversial EM Drive

They didn't actually put in that much energy compared to the thrust they measured.

The fine article says otherwise:

[...] assuming a 500 to 1,000 Newton/kW efficiency EM Drive system.

While the current maximum reported efficiency is close to only 1 Newton/kW (Prof. Yang's experiments in China), Mr. March noted that such an increase in efficiency is most likely achievable within the next 50 years provided that current EM Drive propulsion conjectures are close to accurate.

Best case scenario here is that 1,000 Newton/kW is 100% efficiency in which case their current efficiency is 0.1% or worse. If 1,000 N/kW is not 100% then their current efficiency is even worse than 0.1% in all experiments.

Also, note that Newtons measure force while kilowatts measure power so it makes no sense to express efficiency as a ratio of Newtons to kilowatts. For example, a c-clamp rated at 10,000 pounds-force will produce 44,000 Newtons for an indefinite period of time without consuming any energy/power after the initial tightening.

BTW, a 108 gram apple feels a force of roughly one Newton on the surface of the earth. Using 1 kilowatt to keep an apple suspended does seem extremely inefficient to me. Also note that I can keep an apple suspended indefinitely with a table and no ongoing energy expenditure.

Finally note that the one experiment that got close to one Newton/kW was not done in a vacuum. It would not surprise me if that one Newton of force could be explained by the light-mill effect.

Comment: This is not a photon drive (Score 3, Informative) 480

by DrJimbo (#49596635) Attached to: New Test Supports NASA's Controversial EM Drive

The expulsion (should that not be expulsion or something?) are micro waves ... hence the name: EM drive.

What you are describing is a photon drive where photons are the propellant. But the fine article explains:

After consistent reports of thrust measurements from EM Drive experiments in the US, UK, and China -- at thrust levels several thousand times in excess of a photon rocket, and now under hard vacuum conditions -- the question of where the thrust is coming from deserves serious inquiry.

The reason I don't believe it is real is the same reason I don't believe cold fusion is real. They put in metric ton-loads of energy and measure a very small effect. They say they will need to increase the efficiency by many orders of magnitude to create a practical device. I say they probably made a mistake somewhere and the tiny effect they measured is either noise or due to something else they haven't yet accounted for.

Comment: A perfect combination (Score 5, Funny) 480

by DrJimbo (#49596237) Attached to: New Test Supports NASA's Controversial EM Drive

They say one of the limiting factors (aside from violating the laws of physics) is the political will to launch a large nuclear power plant into space. The solution is obvious: use Cold Fusion to power the EM drive. There is great efficiency here because they can get two Nobel prizes with only one gadget.

Comment: Re:It wasn't the tweet (Score 2) 185

by DrJimbo (#49583759) Attached to: How One Tweet Wiped $8bn Off Twitter's Value

Given the way traders think that is the damage that they caused. A few more cases like that and perhaps they will consider that they need to spend a couple of billion on making the bots not panic.

Wall Street will never police itself. It is entirely geared around making as much money as possible with absolutely no concern whatsoever about what is good for society or for the economy in general.

The only real solution is very simple and very easy. Simply tax the transactions. It can be a tiny fraction of a cent per transaction. This will add friction which will slow down this hypersonic trading. The whole thing is ridiculous. These superfast computerized trades are not providing a benefit to society. In fact, they lead to instability which is the exact opposite of what is good for society as a whole.

If we don't do this than the instability will lead to Wall Street crashing our economy again. It is like the RIAA wanting to be paid to make it difficult for people to listen to music. Wall Street is making money hand over fist by making our entire economic system unstable.

Comment: In defense of "makerspace" (Score 2) 167

A quick Google(makerspace) brought me to the Wikipedia:

A hackerspace (also referred to as a hacklab, makerspace or hackspace) is a community-operated workspace where people with common interests, often in computers, machining, technology, science, digital art or electronic art, can meet, socialize and collaborate.

I'd like to highlight the entire quote. It explains concisely how a makerspace is a particular kind of workshop in terms of what kind of work is focused on and especially the community aspects of socialization and collaboration. The distinction is important because people are encouraged to come to makerspaces to participate and socialize while workshops in general tend to be closed to the public and usually won't even lend you tools.

A car analogy would be you complaining about the new-fangled term "ATV" which refers to certain kinds of vehicles and you suggesting the older and more generic term "vehicle" be used instead.

Comment: Re:me dumb (Score 1) 157

by DrJimbo (#49549233) Attached to: Wormholes Untangle a Black Hole Paradox

I'm not sure I understand what prevents me from transmitting FTL. If I take it to the extreme and use very distant particles, what happens between when I measure one and the time at which light would reach one from the other?

The part you are missing is that the effect is very subtle. It only shows up in a statistical analysis after the fact. You can only notice/measure the effect if you repeat the experiment many times and compare the statistics of what is happening with particle B to the measurements made on particle A. If you look only at particle B then you have no clue about what was going on with particle A and if you only look at particle A then you have no clue about particle B. It is only when you combine information from particle B with information from particle A, after the fact, that you see any effect at all.

To learn more search for "EPR paradox". Basically what happens is that quantum mechanics violates locality without violating causality. This violates our common sense which is based on classical mechanics. Since wormholes are also non-local, connecting entangled particles with wormholes is more appealing to our common sense (for certain values of "common sense"). The interesting thing is that quantum mechanics already explains (predicts the outcomes of) entanglement experiments without any wormholes. So if you add wormholes (in any meaningful way) then you might need to change quantum mechanics. This is interesting because it might lead to a way of combining relativity with quantum mechanics which has been the unobtainable holy grail of theoretical physics for many years.

The chances of this working out are very very small. The chances of getting a Nobel prize if it does work out are very high.

Comment: Re:Somewhere in the middle... (Score 1) 341

by DrJimbo (#49524403) Attached to: Study Confirms No Link Between MMR Vaccine and Autism

1. Why have vaccines and autism rates both grown exponentially in the last 25 years? (no, detection does not come close to answering)

Oh for goodness sake, are you claiming these are the only things that have grown rapidly over the past 25 years. Sugar consumption has grown rapidly. Maybe, just maybe, the mother's freakin' diet has something to do with autism. Why, yes it does. That one study does not explain the majority of cases of autism but it is a big red flashing neon sign pointing in a direction to look. In addition to eating too much sugar, which we now know can trigger autism, there are many many other things mothers are exposed to on a daily basis in modern societies that may also be detrimental to the health of their babies such as: an overabundance of drugs (in food and water), other highly processed foods, chemicals from plastics that get into food and water, and many forms of pollution. Perhaps it is related to increased stress or lack of sleep.

Many years ago, some shyster dickhead of a scientist made a bunch of money (from a firm that was already planning a law suit over the MMR vaccine) by concocting lies about a connection between the MMR vaccine and autism. The science system worked, the lies were caught, the paper was retracted and the shyster lost his "scientist" badge.

What baffles me is that so many people cling to the results from the exposed shyster who truly was only in it to make a bunch of bucks while they ignore all the reputable scientific studies that don't agree with the conclusion they have already jumped to. I'm reminded of Feynman's description of cargo cult science. One problem with your completely irrational position (on the fence or not) is that it causes us to waste valuable and limited resources following up on things we already know are dead ends so we can't use those resources to look for the real cause of the increase in autism.

Comment: Re:We can learn from this (Score 5, Insightful) 163

Great post! But I take exception to this statement especially in the current context where people think it is wrong that we have the best government money can buy:

You have to accept that we are a competitive species, not a collaborative one. We may do things together, but only in the perspective of self-fulfillment. It's as if individual growth is hard-coded in our genes. Maybe not you, certainly not me, but in average, yes.

I agree that in general we all want to improve our lot in life. I disagree that it is built into our genes for us to screw over our fellow humans in the process. It has been documented in books such as Mutual Aid: a factor of Evolution that cooperation within a species is a much more effective (and prevalent) strategy than competition within a species.

In addition, even if some mild forms of competition within a species are beneficial, I totally reject the carte-blanche you offer to even the most sadistic and psychopathic behavior in the name of "my genes made me do it".

If your assumption that we are for the most part all psychopaths is true then we as a species are completely and totally fucked. The overwhelming evidence is the vast majority of humans are not psychopaths. The problem is that almost literally by hook and by crook we have developed a system where psychopaths tend to rise to positions of leadership in corporations and they have used their power to almost totally subvert the government to their antisocial whims.

If you look up the definition of "psychopath":

a personality disorder characterized by enduring antisocial behavior, diminished empathy and remorse, and disinhibited or bold behavior.

you will see that what you described is psychopathic behavior. While this aberration may have a genetic component, that doesn't make it right; it doesn't mean it is widespread; and it certainly doesn't mean we should develop a system that puts psychopaths in positions of great power.

Comment: I like the tablet/laptop two-in-one design (Score 4, Informative) 161

by DrJimbo (#49208207) Attached to: Ultralight Convertibles Approaching Desktop Performance

Speaking of Slashvertisements, I'm running Linux on a Dell 11" 3147 two-in-one. I can use it as a small laptop machine and I can also use it for watching Netflix in the tablet configuration. Although the two-in-one is thicker and heavier than a tablet, it can be better than a tablet for watching videos because there are several configurations where the keyboard acts like a stand so you don't have to constantly hold it.

For me, it was $260 well spent (via the Dell outlet store). I'm pleased with the device even though the Linux support is merely adequate. No multi-touch for the touchscreen and I can't access the accelerometer. AFAIK, everything else works. I wrote little scripts to rotate the display and disable the keyboard and touchpad. I get over 5 hours of battery life while mostly watching videos. I like that the Linux desktop and/or virtual consoles are only a click or two away because I like to tinker. There are a bunch of hardware improvements that would be nice, starting with a lighted keyboard, but for the price, I'm not complaining.

IMO, if the price is decent you might as well buy a laptop with a touchscreen that folds all the way back. I think it is a good use of resources and it makes the device much more versatile. For me personally it is better than a separate tablet and laptop. I may never buy another laptop that doesn't convert to tablet mode.

"It is easier to fight for principles than to live up to them." -- Alfred Adler