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Comment Re:Terrible (Score 1) 407

And yet an action that it was known to be fully capable of doing under other circumstances.

Known by whom? If the victim was not informed that the robot from an adjacent area was capable of entering her workspace, how was she to know it required lock-out/tag-out? Something in the system failed, which is why everybody (the robot manufacturer, the installer, the servicing company, and others) are all being sued: to determine where and why the multiple failures occurred.

Comment Re:Why is income equality necessarily good? (Score 5, Insightful) 516

I think most people argue that income inequality is bad on two accounts.

At the upper end, they argue based on a kind of labor theory of income. They ask, if a certain CEO makes 1000x the income of the average worker, is their work really 1000x as difficult, or 1000x as laborious? The answer is obviously no, but that's not the way our economy works. You could ask the same of movie stars or professional athletes. I don't think this is a useful argument. People at this income level get paid what they can negotiate.

At the other end, they argue that it isn't right for some to be so desperately poor. That's why raising the floor of income (perhaps by a Universal Basic Income) is the other part of the argument. To this I'm much more sympathetic. I live in Los Angeles and don't have to go very far in any direction to find a tent city. People are hurting and they need help.

In my opinion, it's not income inequality that is the real problem, but wealth concentration. The concentration of wealth into fewer hands is bad for the economy. If there is less wealth for most people, then there are less purchasers for an economy's output. It's a deflationary scenario where less available money means businesses have to lower prices to sell, making profits smaller and debts harder to pay off. Bill Gates is only going to buy so many TVs, cars, and houses. Doubling his wealth is not going to change his spending habits. If that amount of wealth was placed in the hands of a thousand people, then there would be a thousand new customers for TVs, cars, and houses. This more distributed kind of customer base can sustain an economy.

From this perspective, extreme income inequality is bad because it leads to catastrophic wealth concentration. The small number of very rich can only be customers to a small number of luxury businesses. Every other business relies on the existence of a much larger customer base that can actually afford their wares. If wealth is too concentrated, there's not enough money in enough hands for most businesses to operate. Businesses suffer and lay off their employees, leading to greater unemployment, leading to even fewer customers, leading to worse business, and on down the vicious cycle.

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

In a normal rocket, the speed you calculated is half the exhaust speed, not the speed of the rocket.

Power = (1/2)*(mass rate of fuel use)*(exhaust speed)^2
Force = (mass rate of fuel use)*(exhaust speed)

Power/Force = (exhaust speed)/2

Rockets are also machines that give a constant force at constant power, but both of these are constant because the exhaust velocity is constant. For the EM drive, if it really has no exhaust, then all these equations go out the door since momentum is not conserved and that means all calculations are inconsistent with our current knowledge of physics. "Over unity" no longer has any meaning.

I'm still waiting to see what happens.

Comment Re:Must be hiding (Score 3, Insightful) 205

Prior to the Mercury controversy, Uranus was found to be moving in ways not described by Newton's theory of gravity. Again, there are two solutions: our description of gravity is wrong, or there is an unseen ("dark") mass pulling on Uranus. In this case, it was dark matter, namely the undiscovered Neptune.

Both modified gravity and dark matter have been solutions to past conflicts between theory and measurement. There's no need to assume there's some conspiracy suppressing this or that idea.

Also, sometimes it takes a long time between a theoretical proposal to explain a mystery and direct detection. The neutrino was hypothesized in 1930 in order to conserve energy and momentum in beta nuclear decays. It wasn't directly detected until 12 years later in 1942. It took 49 years between the first papers proposing the existence of the Higgs boson and its discovery at the LHC. All we can do is search everywhere and be patient.

Comment I know: reading TFA is doing it wrong (Score 5, Informative) 499

Not only did the summary leave out the actual conclusion from the study (what was mentioned were stats before the masking) but also failed to mention the important finding:

Lerner dug into her data and came up with her own guess for the cause of the surprising results: women were leaving the platform after having one or two bad interviews. In other words, women, feeling discouraged, seemed to be just giving up on interviewing altogether. “Once you factor out interview data from both men and women who quit after one or two bad interviews,” she writes, “the disparity goes away entirely.”

Lerner’s findings here do correlate to some things academic research has also shown. She pointed to one study that found that after giving a scientific reasoning test to male and female undergrads and asking them how they fared, women underrated their own performance.

Both men and women perform better when two lessons are learned:
(1) Failure is not permanent, try again;
(2) Practice and training are valid ways of progressing in a technical field. The ability you are born with is not fixed for life.

Submission + - LIGO Reports Second Black-Hole Merger (

An anonymous reader writes: Four months after announcing their epoch-making discovery of gravitational waves — ripples in the fabric of space-time — the Laser Interferometer Gravitational-Wave Observatory (LIGO) team and Virgo collaborators announced today and reported in Physical Review Letters that they’ve detected a second gravitational-wave signal. LIGO spokesperson Gabriela Gonzalez called it “a promising start to mapping the populations of black holes in our universe.”

Comment Re:free will IS bullshit (Score 3, Insightful) 386

Then there is no such a thing as free will, but rather an electrochemical process weighing the choice and the largest or smallest weight being preponderant.

The physical implementation of an abstract concept does not negate the abstract concept. Otherwise, there's no such thing as computation, just voltages and currents pulsing through printed circuit boards, signifying nothing.

Frankly free will does not exists and such study confirm it : our choice are dictated by our memory, education, past, and perception.

If our choices were not dictated by such things, they would be random. What else could we base our choices on?

In any case, the experiment in the TFA does not address free will, but an implementation detail of a mind. It's interesting, but not philosophically significant.

Comment Re:Classist (if that's a word) (Score 3) 84

Key Features
        - Use your personal device to connect to LinkNYC’s super fast, free Wi-Fi
        - Browse the web and access city services, maps and directions from the tablet
        - Make free phone calls to anywhere in the U.S. using the Vonage app on the tablet or the tactile keypad and microphone. Plug in your personal headphones for more privacy.
        - Use the dedicated red 911 button in the event of an emergency

        - Charge your device in a power-only USB port
        - Enjoy more room on the sidewalk with Link’s sleek, ADA-compliant design by Antenna
        - View public service announcements and more relevant advertising on two 55” HD displays

Comment Re:pointers & C (Score 1) 437

The "allocate in the constructor, clean up in the destructor" pattern ... is still just as error-prone (just fewer places for errors), and the fact that the destructor doesn't get called if the constructor throws isn't broadly internalized by coders (and is my least-favorite intermittent resource leak to run down).

I've come up with my own pattern (probably not original) for dealing with throwing constructors and I've been wondering if it's effective. Basically, write a separate cleanup() method that gets called by the destructor and the catch() block of a constructor:

    { // ... do stuff and acquire resources
        throw; // to prevent Foo instance from being used


{ // release any acquired resources

Comment Re:How Big an Improvement Are We Talking Here? (Score 1) 92

Not quite. There are very few algorithms that will see a substantial speedup on quantum computers, factoring numbers and simulating quantum systems being the big two. In fact, it wasn't until Shor's algorithm was discovered that physicists really took an interest in quantum computers since no one knew if there was anything a quantum computer could do better than a Turing machine. For general problems, you can only get a modest speedup over a brute force search on a classical computer. To find an entry in an unsorted database takes O(n) on a classical computer and O(sqrt(n)) on a quantum computer (Grover's algorithm). To get better results, the problem has to have some special property that is amenable to encoding in a quantum system (the quantum Fourier transform in the case of Shor's algorithm).

For now, it seems that quantum computers won't help with NP-complete problems.

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"The eleventh commandment was `Thou Shalt Compute' or `Thou Shalt Not Compute' -- I forget which." -- Epigrams in Programming, ACM SIGPLAN Sept. 1982