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Comment Re:Question for the Physicists. (Score 1) 79

> A magnet exerts force, no?

A permanent magnet creates a static magnetic field, which can exert forces against moving or spinning charges.

> Exerting force requires energy, no?

What do mean by 'exerting'? Generally the answer is 'no'. Magnetic fields will bend the motion of charged particles.

> Where is the energy in a magnet?

A magnetic field has an energy density everywhere in space proportional to the square of the field strength.

Where did it come from in a permanent magnet? It happens that electrons, on their own, naturally make a magnetic field because they are born that way and they can't ever stop doing that. But almost all of the time, electrons are pointing in random directions so their fields cancel and don't add up to very much. Except in a permanent (ferromagnet) where certain unusual properties of the electron clouds in the compounds make it energetically favorable for certain electrons to line up in an organized formation in the same direction, whereas most of the time, it's the other way around, the lower energy state is when the electrons oppose one another so there's no big magnetic field. So in that case any energy in formation comes from the chemical reactions to make the material itself.

Comment Re:Weird (Score 3, Insightful) 239

> Kids in high school often don't really know what they want to do

For many that's true.

For the ones who are driven to become top level scientists and engineers (and writers!), it is not. How many professional basketball players weren't really that interested in sports in high school?

I went to university with a now famous mathematician---he was doing research on string theory at age 17 with Ed Witten. Now, he's an outlier among outliers, but the point is true.

Comment It's obviously not that. (Score 5, Insightful) 470

> I absolutely do not understand this OBSESSION with fetuses, followed by the most callous treatment imaginable for the rest of their lives that conservatives espouse.

The problem is that you are believing their words.

Of course, the position is completely nonsensical and hypocritical if one imagines the goal is devotion to needs of health and life of fetuses.

The explanation which is consistent, however, is the recognition that Forced Accidental Parenthood is awful, and that's the entire point of it: because the true goal is to punish, perhaps for a lifetime, poor young women who had sex and further inflict this punishment on their spawn to hurt the mothers even more and use as a fearful example to others.

Comment Re:Some privacy is more equal than other (Score 5, Insightful) 470

| Are PP's employees "entirely different" from policemen?

Yes.

Your doctor talking to you is different than a policeman's official actions in *public*. It is similar to you talking with your lawyer. Besides, the defendants in the current issue also fraudulently misrepresented themselves which aids proving ill intent. Regarding policemen, the equivalent would be fraudulently misrepresenting oneself as a psychologist for law-enforcement officers and engaging in private conversations in private, taping them, and then publicizing them to shame policemen and the police department as a collective.

What do school vouchers have to do with anything? There is a Constitutional argument there because there is a long-established constitutional restriction particular to religion.

> After eight years of being racist, dissent is patriotic once again.

Dissent wasn't the problem. """dissent""" which accused Obama of not being a native-born American despite conclusive evidence was clearly a proxy for bigotry as it is about identity not ideas or policy. Secret Muslim sharia sympathizer (despite droning thousands of terrorists to death and whacking Osama) too is pretty much bigotry and not policy dissent.

Comment Re:Smart enough to REALLY f*ck things up??? (Score 1) 231

> Currently intelligence is not well defined

To the contrary, in the technical domain, the 'g' factor in the psychometric literature (you can call it 'general intelligence' or IQ) is well defined and has a quantitative meaning. In particular, it represents the empirically observed phenomenon that across a variety of cognitive/neurological tasks of different natures, there is a statistical tendency among humans for people who are pretty good at many of them have a much higher probability than background distribution of performing well on others. The tasks that don't correlate well don't get put into 'intelligence' tests, say like running and catching a fast moving ball.

The degree is how much this incorporates the aspects of the human word 'intelligence' in social situations.

Using the psychometric definition, it's clear that the machine intelligences can't even be measured because the background assumptions about correlations is false: 99.9999999% performance outlier on Go, brain-death on everything else.

Because machines today have no general intelligence---and it may not matter.

Comment Re:Money != Smart (Score 1) 231

Musk is a firm reality-acceptor when it comes to the technological issues facing his businesses: energy storage, battery manufacturing, car manufacturing, and liquid kerosene fueled rockets. He knows how hard they are and what it takes.

If a software company CEO said oh 'look at the progress in batteries, in 30 years, they will have 50 times the energy density of gasoline', he'd honestly be upset by this wild overselling, and the scientists will describe the energy and chemical constraints of the laws of physics that make that prediction ridiculously wrong.

But he's doing the same thing with AI.

Comment Re:CEOs are smarter than anyone (Score 1) 231

> The experts in any field tend to be focused on the problems and obstacles, and are often the unduly pessimistic about progress. In hindsight, they often turn out to be the worst predictors. It is hard to see the horizon when you are in the trenches.

Do you have widespread examples about this?

Comment Re:That quote can't be right. (Score 1) 273

All else being equal, the surface temperatures in Kelvin will go as the fourth root of the flux, because emissivity is proportional to T^4 and you presume that outgo = incoming energy in rough equilibrium. So temperatures in Kelvin varying by 2.3, which is still a huge difference but not 30.

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