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Space

New Class of Stars Are Totally Metal, Says Astrophysicist 119

KentuckyFC writes Stars form when clouds of gas and dust collapse under their own gravity, generating enough heat and pressure to fuse the atoms inside them together. When this cloud of dust and gas is the remnants of a supernova, it can contain all kinds of heavy elements in addition to primordial hydrogen, helium and lithium. Now one astrophysicist has calculated that a recently discovered phenomenon of turbulence, called preferential concentration, can profoundly alter star formation. He points out that turbulence is essentially vortices rotating on many scales of time and space. On certain scales, the inertial forces these eddies create can push heavy particles into the calmer space between the vortices, thereby increasing their concentration. In giant clouds of interstellar gas, this concentrates heavy elements, increasing their gravitational field, attracting more mass and so on. The result is the formation of a star that is made entirely of heavy elements rather than primordial ones. Astrophysicists call the amount of heavy elements in a star its "metallicity". Including preferential concentration in the standard model of star formation leads to the prediction that 1 in 10,000 stars should be totally metal. Now the race is on to find the first of this new class of entirely metal stars.

Comment Re:I work IT in the taxi industry. (Score 1) 273

And what happens when a passenger makes unreasonable demands - "Hey, I need to stop here and do some shopping, so you just wait here, and BTW, I only have half the money, so you won't get paid what I agreed to pay." - and then threatens to give the driver a bad rating if they complain about it, what mechanism is there to address that deliberate libel once it's posted publicly? Sure, the driver can give the passenger a bad rating, too, but that won't help him any.

And that is the failing of relying solely on a reputation system. There's no protection against liars.

Comment Re:Trust (Score 1) 273

Uber drivers, as a rule, don't have insurance. There have already been lawsuits over it. Your private insurance will not cover you if they find out you're driving someone for money. Your private driver's license is not good enough, either. So, in most states, when you use Uber, you're riding in an uninsured car with an unlicensed driver, and if there's an accident, you, the passenger, are 100% responsible for whatever medical expenses you have (because the driver will be spending all his money to avoid prison).

Comment Re:I love getting into strangers' cars (Score 1) 273

The ratings-and-feedback systems maintained by Uber and others is more efficient at flagging bad drivers, than any government-run certification authority can be.

I'm sure that will be a great comfort to those who are the reason for those bad ratings. You know, the people who get ripped off, kidnapped and held for ransom (I need another $500 or I'll just dump you here), or worse.

And the cops will be less than enthusiastic about chasing those bad drivers down, when there isn't a multi-million dollar a year company to fine the hell out of.

Comment Re:The answer nobody likes... (Score 0) 286

What you advocate is, literally, complete lawlessness and anarchy, no law at all. Because if you are the victim of a crime, what you advocate is do not report it to the police, or anyone else. And at that point, anybody can do anything they like to you, confident that there will be no negative consequences.

Do you realize this?

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I have hardly ever known a mathematician who was capable of reasoning. -- Plato

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