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Comment: Re:And still (Score 2, Informative) 196

by buchner.johannes (#49155837) Attached to: One Astronomer's Quest To Reinstate Pluto As a Planet

How dare you challenge the might of Jupiter! It weighs 320 times the mass of Earth -- even if those 100,000 trojan asteroids weighed as much as its minor moons (which they don't, they are 0.0001 Earth masses according to wikipedia), it would still dominate its gravitational field by several (9) orders of magnitude.

Compare that to Pluto: Charon already weighs 10% of Plutos mass. The center of rotation in that system is not even inside Pluto.

Also, there are other criteria that apply: a planet has to be spherical due to gravitation (there is a more technical definition). Is that the case for Pluto?

Finally, you can not have 9 planets anymore. You can choose between 8 planets and 13 planets, the latter group growing every year.

Comment: High variance, low validity (Score 1) 389

by buchner.johannes (#49073529) Attached to: What To Do After Robots Take Your Job

"My predictions have enormously high variance, I can imagine completely plausible, incredibly positive scenarios, but they're only about as probable as actually quite dystopian futures that I can imagine."

The future is uncertain, and we can not predict this aspect with the information we have. So how valid is the 30-50% number then, if it is +-50%?

Comment: Re:2x power (Score 3, Insightful) 89

by buchner.johannes (#49062235) Attached to: Scientists To Hunt For Supersymmetric Particle In LHC

Even if you turned off Hawking radiation, it would still be hard for a black hole from a particle accelerator to actually eat the planet. Let's say you have an accelerator much more powerful than the LHC, with a center-of-mass energy of 1 PeV. If all that were used to produce a black hole, it would have a mass of 1.8e-21 kg. An electron or proton a single hydrogen radius away from it (which we can use as a typical intermolecular distance in the Earth for simplicity) would feel an acceleration of 1e-11 m/s^2, which is absolutely tiny compared to the electrical forces that govern motion on those scales. A small black hole like that behaves much like a neutrino - it hardly interacts with anything. And it needs to do that to grow. I think we could have lots of these inside the Earth and not even notice (dun-dun-DUUN!).

There is an even easier answer to address the fears about LHC micro-black holes. Particles with energies comparable or exceeding LHC energies hit the atmosphere of earth every day, and we observe their effects with Cosmic-ray observatories such as Cerenkov Detectors. Business as usual, and nothing exciting happened for the last billion years.

Comment: Re:2x power (Score 1) 89

by buchner.johannes (#49062147) Attached to: Scientists To Hunt For Supersymmetric Particle In LHC

Black holes that small would be hard to see. And if created by advanced civilizations with LHC-sized accelerators, very rare. And then these black holes would evaporate via Hawking radiation quite rapidly (on astronomical time scales).

You are way off. Macroscopic black holes, for all intents and purposes, do not evaporate.
A Earth-mass black hole will take 10^50 years to evaporate. (The age of the universe is ~10^10 years).

If you want a black hole that evaporates within a reasonable time, like the age of the universe, you are looking at 10^11 kg. That is tiny compared to a planet, somewhat comparable to the Great Pyramid of Giza.

Comment: Re:The Secret of Nim (Score 1) 520

by buchner.johannes (#49061093) Attached to: Nim Programming Language Gaining Traction

Nim looks syntactically a little bit like Kotlin, which compiles to either JVM bytecode or JavaScript. If you compile to the JVM then you can not only use libraries written in Java, but also JavaScript, Python 2.x (via Jython), Ruby, Scala, C (via JNA), there's even a Haskell for the JVM called Frege.

Unfortunately, many Python packages use compiled C code (Cython etc.) which only work in CPython, i.e. not in Jython, not even in PyPy. The most important such difficult-to-port package is NumPy.

It is the quality rather than the quantity that matters. - Lucius Annaeus Seneca (4 B.C. - A.D. 65)