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Comment Re:+2/3, -1/3 (Score 1) 95

Thanks - so why don't the charm and the anti-charm go "poof" ?

They might not be antiparticles of each other, as they might differ in color charge.

I think that would violate color confinement because the resulting pentaquark would have a net color.

Red up quark, blue down quark, blue charmed quark, green up quark, antiblue anti-charmed quark. Net color = R+B+B+G-B = R+B+G = colorless. (Shamelessly lifted from the "2015 LHCb results" section of the Wikipedia page for the pentaquark.)

Wait ... the two charmed quarks you mentioned are in fact anti-particles.

Did you mean to swap the blue and green on the charmed and up quarks? That would in fact make the charmed quarks not anti-particles to each other. I'm not sure that's even possible (I'm not an expert on the standard model, let alone pentaquarks) but I assume it would at least not violate Pauli exclusion (because the two up-quarks aren't the same color.)

Comment Re:Question about deep space pictures (Score 2) 108

Since the amount of light that is cast on an object is exponential with regard to distance

You mean inverse-square with respect to distance. The inverse-square law applies when the source is a point (or uniformly-luminous sphere that is far enough away.)

Pluto is about 40 AU away from the Sun, whereas the Earth is 1 AU away. That means sunlight on Pluto's surface is about 1/40^2 = 1/1600 as bright as on the Earth's surface. That's dim, but not hard to record with good optics, a sensitive detector, and enough exposure time.

Comment Re:Yeah (Score 1) 92

Shares don't have an average daily volume.

Correct. Share's don't. Public companies do. Therefore we say "Company X has an average daily volume of Y shares."

So a correct FTFY would be "TWTR has a Average Daily Volume of 20,664,680 traded shares.

The traded qualifier is implied. Nobody bothers to add it, except for those who are pedantic. And speaking of that:

If you're going to be pedantic, at least be correct.

You might want to follow your own advice.

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