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Comment Re:Limits of Measurement (Score 2) 144

This isn't a perfect analogy, but think of a kink in the carpet. You can push it around, like a object, but you can't make it disappear without taking out some slack in the carpet. Now if we define this kink as a particle, it IS a particle. Using this definition, the particle doesn't have a precise position, nor a rigid shape. But a quantum particle isn't at all like a classical big object, which still has a precise position although it is extended over space. The difference is that a quantum particle appears to be a point particle whenever you look at it, located randomly on a screen in a region where the screen intersects the quantum particle wavefunction. That is, the wavefunction can be so large that the particle basically should cover the whole screen, but we only see a single dot on the screen somewhere. By 'appears to be a point', I mean that the particle collapses onto the resolution of the screen, no matter how high resolution the screen has, to the limits which we can make screens, and a single particle won't excite two neighboring screen pixels at once. Unfortunately, I don't think there's any way to understand this classically.

Comment Re:Limits of Measurement (Score 5, Informative) 144

IAAPhysicist. Parent isn't correct. I advise you to not worry too much about what is "real" and accept that physics looks for simple models which match our experiences. You need to think abstractly, and assume less. For example, everyone grows up with some intuition of what an object is, and then project that notion into realms where they don't apply. The letters on this webpage, for example.... These are black objects which move up and down when you scroll the page. Or, is it really the white spaces between the letters which are the real objects, and the black is just void? Actually both are wrong, and the "reality" is that your monitor is doing certain things, depending on how deep you want to look.

When physicists talk about a particle, they are talking about the smallest step in the amplitude of the fluctuation in some field or combination of fields. A fluctuation doesn't have to be purely one kind of field; for example, a phonon is made out of collective motions of atoms, and polaritons are sort of some mix of photon and phonon. These could be considered particles (but not fundamental particles). This isn't the only way to think about a particle (since it's all just a model anyways), but it is more accurate than billiard balls.

Heisenburg uncertainty principle exists because you are trying to pinpoint a fluctuation in fields which occupy all space.

Parent's description of the double slit experiment is fully wrong. Electrons do not interfere with some build up of electrons. Electrons interfere with themselves, because the fluctuation (which is the electron) exists in the full region between the source and screen. The interference pattern is the same no matter how slowly (in terms of electron rate) you fire the electrons, so build up is not a concern. A similar interference pattern exists in photons and neutrons as well, which aren't charged.

Comment Re:Mostly done by 1985... (Score 1) 227

From the perspective of someone falling in, the time to reach the singularity is not only finite, but quite short.

Assuming a static black hole exists in the first place. What if the black hole is changing on the time scale of the person falling in?

The Schwarzchild metric assumes that the mass distribution is stationary over some infinite duration. If black holes evaporate, then won't it evaporate before the person reaches it? What about cosmic expansion?

Comment Re:Non-compete agreements are BS. (Score 0) 272

Freedom to sell yourself into slavery is not freedom. You seem to have some libertarian idea of freedom where a contract can trump freedom. If you are truly free, you can sign a non-compete if you want, but you are free to ignore the contract. That's basically what California says: you can sign the non-compete; it just has no power under most circumstances. There's nothing more free than that. Or are you a statist, who thinks that states should enforce contracts that violate rights, by enacting Jim Crow laws. If a contract has to be enforced, then it's not free.

Comment employer health insurance is bullshit (Score 1) 1330

It harkens to the old days of the company store and the company town, where the company are "taking care of the employees" but are actually just indenturing them to the company. I'm not saying there is some national conspiracy between the insurance companies and corporate overlords to keep the peons in line, but why then is the outcome exactly as if such a conspiracy existed?

Comment Re:Creating emotional response is not the issue (Score 1) 219

There is no big difference between this and market research. The reason why this got more attention is because people are panicky animals and behave unpredictably. They need to be told (or suggested) what to believe, and they will adhere to this idea and so you get memes spontaneously appearing, and some ideas, including outrage, will pop up seemingly out of nowhere. We see this effect in research in music popularity (http://www.npr.org/2014/02/27/282939233/good-art-is-popular-because-its-good-right)

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