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Comment Re:Galactic North... (Score 1) 268

I don't see the approximation I read in an astronomy book and that I still use, so here it is:

Think of the universe as an hyper-sphere. Well, this is actually hard, so remove a dimension: we're left with a sphere in space, like a balloon, and that balloon is inflated (*).
At the time of big-bang, the balloon was a point, and it is expanding.
To be clear, as we removed a dimension, the universe is the balloon surface, not the volume.

Pear-shaped I guess would point to center / past, but I guess they mean pear-shaped in three dimensions, so that could mean the 4th-dimension "inertia" imbalance has effects in three dimensions, but someone more knowledgeable than me would would have to comment if this makes sense.

(*) AFAIK, if universe's curvature is positive, it's actually an accurate representation. But the universe's curvature is as close of 0 as we can currently measure.

Comment Re:Have to give it to Apple..... (Score 1) 771

I wouldn't blame them for not using micro-USB. I would rather blame them for not using USB Type-C (which is also a reversible plug). Lightning has been used since 2012, but Type-C exists only since 2014, so at the time it made sense. Probably they're keeping Lightning as of now because it's more lucrative in licensing fees, their installed base is big enough that they have no pressure to play nice yet, and there's no way to make every one happy as changing would annoy those that already have these Lightning docks and would have to change them (again, if they had 30-pin docks before).

As for the advantages:
- you're not limited to stereo, as you could enjoy 5.1 with the dock,
- less ports to waterproof (if you're going for that feature),
- either more room for something else like battery, or thinner phones (because extra-thin is somehow a selling point),
- they would rather go to 0 connectors, but the performance isn't there yet.

Comment Re:Not Slytherin eh? (Score 1) 117

Of course it's hard to place Donald Trump in one of the buckets. He has no opinion. It's one now, an other the day after and other the day after that.
For Donald Trump winning is more important that anything else, not truth or making clear what his plans are for the country. And some people like what is perceived a strong leader. He's just a bullshitter.

According to Dumbledore, the qualities that Slytherin prized in his handpicked students included his own rare ability to speak Parseltongue, resourcefulness, and determination. He also selected his students according to cunning, ambition, and blood purity.


In other words, a perfect match for Slytherin, right ?

Comment Re:lack of international cooperatiom (Score 2) 192

US courts have a tendency to hand down draconian sentences for even trivial infractions thanks to the 'come down on him like a ton of bricks' attitude to justice among politically ambitious US judges and prosecutors.

My understanding is that many judges in the USA are elected, so I wouldn't put the blame on the judges but on the electors. You just get what you (collectively) asked for, for better or worse.

This has resulted in an extreme reluctance in other countries to extradite people to the US

I'm not sure about that. However, some countries, and this includes Germany, forbid extradition of their own nationals.

Comment Re:because ... (Score 2) 237

I don't get the same results (*) :

Arc formed by a grain of coarse sand one kilometre away:
(2 mm / (2 * pi * 10^6 mm )) * (360 / (2 * pi)) = 180 * 10^-6 / pi^2 = 18 * 10^-6

Arc formed by an asteroid of 37m 14 million km away:
(37 m / (2 * pi * 14 * 10^9 m )) * (360 / (2 * pi)) = 238 * 10^-9 / pi^2 = 24 * 10^-9

So, that would be 750 times smaller that a grain of sand a kilometre away.

(*) But I've been wrong in the current discussion already, so don't believe me and double-check ;)

Comment Re:So how do we miss a 300 foot object that has be (Score 1) 237

sphere area is 4 pi r^2

Oops, right, I even had it in front of my nose when checking for steradians. I always mess up some mundane detail.

With that in mind, this gives:
Asteroid cross-section: pi * 1.6 * 10^3 m^2
Sphere surface: pi * 7.84 * 10^20 m^2
Solid angle: 2.6 * 10^-17 sr
Number of such asteroids that could fit onto the sphere: 4.9 * 10^17
Compared to the land surface of the USA: 18,7 mm^2, or a disc with a diameter of 4.9 mm.
Compared to the surface of the earth: 10,4 cm^2, or a disc with a diameter of 3.6 cm.

Comment Re:So how do we miss a 300 foot object that has be (Score 2) 237

I would have up-moderated, but some of the computations seem off...

Sphere area is pi * r^2 (*).
So, for 80m diameter, radius is 40m, that would be pi * 1.6 * 10^3 m^2. Cross sectional area with a sphere differ, but for a 14 * 10^6 km radius sphere, curvature is small enough to ignore.
Sphere with a radius of 14 * 10^9 m has a surface area of pi * 1.96 * 10^20 m^2.
Solid angle formed by the asteroid is (pi * 1.6 * 10^3) / (14 * 10^9)^2 = (pi * 1.6 * 10^3) / (1.96 * 10^20) = pi * 8.2 * 10^-18 = 2.6 * 10^-17 sr
Number of such asteroids that could fit onto the sphere is (pi * 1.96 * 10^20) / (pi * 1.6 * 10^3) = 1.225 * 10^17 (that one was correct)
Compared to the land surface of the USA (9.15 * 10^6 km^2), that would be (9.15 * 10^12 m^2) / (1.225 * 10^17) = 7.47 * 10^-5 m^2 = 74.7 mm^2, or a disc with a diameter of 9.8 mm.
Compared to the surface of the earth (~510 * 10^6 km^2), that would be (510 * 10^12 m^2) / (1.225 * 10^17) = 416 * 10^-5 m^2 = 41.6 cm^2, or a disc with a diameter of 7.3cm.

I guess Muphry's law applies, will someone double-check ? :)

(*) When do we get enough Unicode for greek and math symbols ?

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