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Comment: Re:Which side is upwards? (Score 1) 120

Rotating the nut clockwise always moves it away from you; rotating it counter-clockwise always moves the nut towards you. You're flipping your position axes (looking from the top/bottom) but keeping your velocity axes the same (moving in the same direction), hence the direction of rotation flips.

+ - Teacher Goes Back To Classroom After Being Removed For Science Fair Project

Submitted by As_I_Please
As_I_Please (471684) writes "In a followup to a previous story, Greg Schiller, a high school biology and psychology teacher in the Los Angeles Unified School District, returned to his classroom this past Monday after two months of suspension. The suspension came after complaints that two of his students built allegedly dangerous science fair projects: a pneumatic marshmallow launcher and a coil gun capable of launching a metal projectile several feet.

In addition to students being deprived of a qualified teacher for two months with just a week before AP exams, the school's fencing team was without a coach and could not compete in competitions, and the teacher's union was without their representative during contract negotiations.

The school district has not announced whether it will pursue any other disciplinary action."

Comment: Re:Electron crashing into the nucleus (Score 1) 193

Mostly quantum mechanics. The fact that an electron can only exist at certain distances from the nucleus has to do with its wave properties. It's similar to how there is a minimum frequency that a guitar string can vibrate at due to its length, tension, and mass. Due to the forces and energies involved, there is a minimum distance that an electron can exist from a nucleus.

However, sometimes that minimum distance lies inside the nucleus. The element mercury (among others) can capture one of its own inner electrons. A proton reacts with the electron to form a neutron and a neutrino. Mercury minus one proton is gold.

Comment: Re:What about size? (Score 1) 150

by As_I_Please (#45750679) Attached to: "Perfect" Electron Roundness Bruises Supersymmetry

The summary and articles are a little vague about what the "shape" of an electron is supposed to be. As are as we know, an electron is a point particle, meaning it has zero size. What these scientists mean by "spherical" is that the electron's electric field is perfectly spherically symmetric (measured to a higher degree of accuracy than any previous measurement). This means that if you imagine a sphere with an electron at the center, then the electric field of the electron is exactly the same magnitude over the entire surface of the sphere. If the electron had a dipole component, as many supersymmetric theories predict, then the electric field of the electron would be stronger on one side of the imaginary sphere. The scientists did not measure any dipole component.

Comment: Re:Just imagine (Score 1) 845

by As_I_Please (#45566745) Attached to: No Shirt, No Shoes, No Service — and No Google Glass, Either

Yes, we might finally get a court ruling that the Civil Rights Act is blatantly unconstitutional because it infringes on the property owner's right to refuse service to anyone for *any* reason, and the resulting crazy would be fun to watch from the other side of the ocean.

I'd like to know where in the Constitution this right is established.

Comment: Re:I get what he's saying here (Score 1) 438

by As_I_Please (#45126411) Attached to: <em>Gravity</em>: Can Film Ever Get the Science Right?

The only physics bit that bugged me was the tether scene. Spoilerish. Two astronauts tied together falling past a structure, once one of them grabs on and withstands the shock of the other astronaut snapping the tether taut, he should rebound back towards the secured astronaut, not dangle as if still being pulled by gravity. This would not be the case if, say, they were on a rotating structure or on a rocket making a significant burn but neither is the case.

[More Spoilers]
I've seen this film twice now, and I think I know what was happening. The astronauts were swinging in an arc on the tethers. The force pulling Clooney away was centrifugal force. Even after catching him, their momentum would still be carrying them sideways, requiring more centripetal force than the loose straps around Bullock's legs could provide.

Comment: Re:Speed of light violation implication? (Score 4, Informative) 46

by As_I_Please (#44338599) Attached to: Muon Neutrino To Electron Neutrino Oscillation Conclusively Shown

This explanation is insufficient. If neutrinos were indeed massive particles we'd see a wide distribution of their velocities, just like we can observe slow and fast protons, slow and fast electrons, slow and fast everything that moves slower than c. Yet, in 100% of experiments that have been done all neutrinos are propagating through space at the speed close to or exactly equal to c.

The reason for this is the extremely small mass of neutrinoes. The current experimentally-derived upper bounds on their mass is around 1 eV (in contrast, an electron has a mass of 511,000 eV). This means that any process that creates a neutrino will give it enough energy to send it off at ultrarelativistic speeds. Even something simple like neutron decay can impart 1 MeV of kinetic energy to a neutrino, which, as the grandparent calculates, means the neutrino is traveling at 0.999999999999*c. Only chemical reactions would release a small enough amount of energy to have non-relatvistic neutrinos. But, chemical reactions don't release neutrinos.

This is why we only see speed-of-light neutrinos. This is also why it's taken so long to discover that they have mass.

Comment: Re:Marvelous news (Score 3, Interesting) 71

by As_I_Please (#44305863) Attached to: Ancient Mars Ocean Found?

If it were up to me, I'd prefer that Martian life had no relation to life on Earth. Two results from this:

1) It will give us new information on the kinds of life that can exist (Is it carbon-based? Does it need water?). Similarities add constraints on how life must be; differences remove them.
2) It will all but prove that life is plentiful in the universe. If life independently emerged twice in the same solar system, then wherever it is possible for life to exist, it will be found.

Comment: Re:Primes closer together? (Score 5, Informative) 248

by As_I_Please (#43729321) Attached to: Major Advance Towards a Proof of the Twin Prime Conjecture

Not quite.

The new result, from Yitang Zhang of the University of New Hampshire in Durham, finds that there are infinitely many pairs of primes that are less than 70 million units apart...

This means that for every prime p such that p+q (where q is less than 70 million) is also prime, there exists another prime r bigger than p such that r+s (where s is also less than 70 million) is also prime. Note that there is no limit to the distance between p and r.

Comment: Re:god, the distros are LAZY, not him (Score 1) 259

by As_I_Please (#42374955) Attached to: After 12 years of Development, E17 Is Out

You might want to try Manjaro Linux. It's based on Arch, so it's a rolling release, but they have their own repositories for testing updated packages before release. Plus, their installer is much less of a hassle than Arch's, including an automatic graphics card driver installer.

Comment: Re:The Invisible Unicorn Argument. (Score 1) 238

by As_I_Please (#42270109) Attached to: Has the Mythical Unicorn of Materials Science Finally Been Found?

Self-creation is nonsensical (violates non-contradiction and all reason);

In my view the laws of reason are just as empirical as the laws of physics. So you have to be careful with what you dismiss as unreasonable. The universe is not bound by human-created reason. Quantum mechanics puts lie to the rule of non-contradiction. Set up a double-slit experiment and fire one electron at a time. When we observe which slit an electron went through, it either goes through A or B, but not both. And yet, we observe an interference pattern, so we have to conclude that the electron went through both slits. Both slits and not both slits. A contradiction in reality, right?

On another note, there's another possibility in the Creation by Other category besides something God-like: Creation by Other Universes. One possibility is that a black hole is where a piece of spacetime twists off from a universe and inflates into its own universe. Universe Zero begets Universe One and was begotten by Universe Negative One. Every universe has a beginning and an end (big rip, heat death, or big crunch), but the set of all universes is eternal. Perhaps in the physics of the metaverse, the null set of universes is impossible. Or, the actual number of universes is infinite and always has been.

Everyone has a purpose in life. Perhaps yours is watching television. - David Letterman