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Comment Re:"it was used for children's writing exercises" (Score 4, Insightful) 235

More generally, "name calling" should be the expected behavior when asking almost any complex question to any large group of persons.

However, in that specific case, Richard Dawkins has the expected default position of any atheist (including me): The existence of an invisible unproven magic being cannot be the answer to any complex phenomena observed in the real world (in that case, that would be the origin of life). That position implies that there are things that we cannot explain with our current understanding of nature (you know, that thing called science).

Improving science by looking for more clues in the real world is the right way to handle those mysteries. Claiming "Magic", "God", "Taboo" or "Holy Book" is not.

Comment Re:Waste of helium (Score 2) 190

Hummm... I was under the impression that the lifting power of H2 was only marginally better than He.
What matters is not the ratio of the mass of H2 with He but their difference with respect to the mass of the surrounding air.

I do not have the right numbers but let's assume that the mass of 1m3 if gas is 1000g for air, 200g for He and 100g for H2.

The lifting power of 1m3 of air is 1000-1000 = 0 (by definition)
The lifting power of 1m3 of He is 1000-200 = 800g
The lifting power of 1m3 of H2 is 1000-100 = 900g
The lifting power of 1m3 of pure vacuum is 1000-0 = 1000g (the maximum)

So we see in that example, that the lifting power of H2 is only 12.5% more that of He even though its weight is half.

Comment Re:From TFA (Score 1) 323

The first chart on shows both the growth rate and the population.

What I find interesting is that the growth rate was at its maximum 2.1% in the 60's and it is now at 1.2%.

During the same time the world population went from 4 billions to 7 billions which means that the raw growth went from 4e9*0.021 = +84 millions/year to 7e9*0.012 = +84 millions/year. So the raw growth was basically constant during the last 50 years.

The current expectation is that the growth rate will continue to decrease and that the population will eventually reach a maximum around 9 billions but be aware that a decreasing growth rate is not a sufficient condition for that. For instance, 1/2+1/3+1/4+1/5+.... is well known example of an infinite sum with a decreasing growth rate. Similarly, 1/2+1/4+/1/8+1/16+... is not an infinite sum (it tends to 1) even though its growth rate remains strictly positive.

Comment Re: sponsored by DRM (Score 4, Informative) 60

The acronym DRM (direct rendering management) first appeared in the Linux Kernel in 1999.

  DRM (digital rights management) is more difficult to trace back because it is a generic term and not a specific technology.

Here are the number of references by Google Scholar for "Digital Rights Management" DRM

1999 = 17
2000 = 43
2001 = 205
2002 = 378
2003 = 740 ...
2010 = 1610

So in 1999, the terminology DRM (digital rights management) existed but was not mainstream. This is consistent with my own memory. At the time I first saw DRM (digital rights management), I already knew about the Linux DRM for a few years.

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

In the famous Hubble deep field image shown at the smallest galaxies are approximatively at 10 billion = 1E10 light years. Assuming that they have a typical size of 100000=1e5 light years (as our own galaxy) that gives us the ratio 1e5/1e10 = 1e-5

The asteroid is 100m = 1e2 meters wide at a distance of 14 millions km = 14 billions meters= 14e9 meters which give a ratio of 1e2 / 14e9 = 7.14e-09

So on the Hubble deep field image, the asteroid would be about 1400 times smaller than the smallest galaxies.

Comment Re:Fly me to the mars (Score 4, Informative) 103

This XKCD picture explains it all in a very intuitive way:

The ISS is on the "low earth orbit" line in the detailed view of the Earth well (on the right).

Using the same analogy, image that you are at the bottom a 100m deep well. It is should be easy for you to walk in circles for 1000m (so horizontally). However, to exit the well you have to GO UP for 100m. That's is a lot more difficult.

Comment Re:"Habitable Zone" (Score 1) 267

So according to that definition, a specie that would reach immortality or that would find a way to prevent all mutations would not be alive anymore? I don't think so.

I won't even try to give better definition of 'alive' because I feel that this is pointless. This is a fuzzy concept so there will always be exceptions and some "things" will never be properly classified.

Comment Re:Would a bear detect the uncanny valley? (Score 2) 152

Also, the Red, Green and Blue components used to reproduce colors are finely tuned to match the absorption rates of the 3 types of cones found in the human eye.

Simply speaking, the colors in our movies and photographs are probably quite unrealistic for most non-human life forms.


Comment Re:A hot I worked for did this once (Score 1) 64

The parent post was not about using unnecessary extensions but about having files or directories with an extension at the ROOT of the filesystem.
None of /usr /etc /tmp .. match the pattern /*.* so rm -rf /*.* should be mostly harmless on most systems.

For instance, on my current box, the only thing that would be removed is the symlink /initrd.imh -> boot/initrd.img-...
That would probably prevent me to boot but that is easy to repair.

Regarding the use of the .sh extension for shell script, I kind of disagree with you.
Extensions are of course not strictly needed since the OS and most applications (not all) do not use them to figure out the filetype but extensions are still a convenient way to identify the nature of a file without having to open it (yeah! yeah! I know the 'file' command).

I confess! I have been using Linux/UNIX almost exclusively for the last 20 years and I still add .sh or .pl to some of my shell and perl scripts even though I know that neither the OS nor my editor will need the extension. That is not as if I had to type the extension each time I want to run the script. Completion is my friend.

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