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Comment: Re:And still (Score 2, Informative) 190

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.

Interesting.
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.

Comment: Re:Such potential (Score 4, Insightful) 520

by buchner.johannes (#49060043) Attached to: Nim Programming Language Gaining Traction

I agree. it needs the curlies (which WORK great in C and takes up at most 3 chars; 1 for the curlie and 1 for a space before and after. 3 extra bytes for intro and maybe 3 for exit. 6 bytes. big deal. you should 'waste' more space with comments and vertical/horizontal whitespace, just for readability, alone.

Haha, here you all complain that Java is too fluffy, but if a language reduces the fluff it is also not good?

In the case of Python, instead of intro/outro curled brackets or begin/end statements AND REDUNDANTLY indenting, using only one of the two was chosen. Why do it twice.

Comment: Re:The Secret of Nim (Score 4, Insightful) 520

by buchner.johannes (#49059971) Attached to: Nim Programming Language Gaining Traction

If I were to create a new language, I would not focus on creating the most beautiful syntax or the best built-in functionality. Instead, I would make damn sure it plays well with other languages and that it is trivial to use software packages already written. For example, R, Python, Java -- no one wants to recode the packages (machine learning algorithms, MPI, web automatisation) in yet another language.

Comment: Documentation (Score 2) 189

by buchner.johannes (#49055505) Attached to: Wayland 1.7.0 Marks an Important Release

Second is the protocol
documentation, which is mechanically generated from the protocol
definitions and works more like a reference manual. Third is the code
documentation, which is also mechanically generated but from the library
source code itself.

That's the right way to do it. They use pelican, xmlto with some customized XSLT and graphviz for maintainable high-level diagrams.

Pretty cool. So far I have only used sphinx (and doxygen before), but these days there are a lot of great documentation options out there.

Comment: Re:Not quite comparable (Score 4, Informative) 215

by buchner.johannes (#49054937) Attached to: Japan Now Has More Car Charging Points Than Gas Stations

At a gas station it doesn't take you long to fill your tamk. Charging an electric vehicle takes a lot longer so theres less turnover.
(Perhaps even all day, or at least all 8 hrs of a shift)

It takes 1 minute, 30 seconds.
A electric charging "gas station" could just replace the batteries in cars and charge its pool of batteries independent of the cars.

Documentation is the castor oil of programming. Managers know it must be good because the programmers hate it so much.

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