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Comment Lack of infrastructure (Score 1) 178

Unfortunately, using your bike to travel in France is suicidal. This is obvious on OpenCycleMap.org if you compare France to Germany, Belgium or The Netherlands.
There are a few bike lanes but not enough to be really useful. Nobody is willing to use his bike regularly to go shopping or work if there are multiple death traps on the way.

 

Comment Re:I dont get it.... (Score 1) 134

Old and recent numbers are difficult to compare in France because the testing strategy is very different. In March, the tests were in very limited supply and were performed according to strict criteria (strong symptoms, people with preexisting conditions, medical staff, ...). The actual number of infected people was around 10 times the official number. This is not a conspiracy theory. That fact was widely known and accepted. For instance, in May, the Institut Pasteur estimated that around 2.8 million people had been infected in France while the official numbers were around 150,000.
  https://www.reuters.com/articl...

Nowadays, everyone can be tested in France (there are delays but this is a separate issue) so a lot of people that would have been ignored in March are now counted. The current numbers are probably a lot closer to reality.

Also, doctors have a better understanding of the disease. They know what works and what does not work. If you are infected today, you are less likely to develop a severe form the disease than in March and if you do you are also less likely to die.

Comment Re:For those wondering what ACTUALLY happened (Score 2) 121

More generally I would bet that this was a locale problem. Changing the locale will affect the sort order of pretty much all characters.

For example, on Linux, the UTF8 locales are ignoring white spaces while the C locale does not.

(bash) export LANG=en_US.utf8
(bash) printf "X 1\nX2\nX 3" | sort
X 1
X2
X 3

(bash) export LANG=C
(bash) printf "X 1\nX2\nX 3" | sort
X 1
X 3
X2

In servers, the locale is usually set to C but on desktop machines it is usually equal set to en_US.utf8 (or whatever your preferred language can be). That has the potential to break a lot of scripts.

Comment Re:CO2 doesn't cause global warming. (Score 5, Insightful) 409

A few millimeters of polycarbonate cannot possibly increase the temperature within a greenhouse? Well, obviously it does and if the 0.04% of CO2 from the atmosphere was compressed to a density similar polyethylene sheets then that would be enough to cover the Earth surface with a few millimeters of solid CO2. Do no underestimate the amount of CO2 in an atmosphere that is multiple kilometers high.

The math is not very difficult.

The mass of the atmosphere is M = 5.14e18 kg
The Earth surface is S = 510 million km = 510e6 km = 510e12 m
So 400ppm = 400e-6 of CO2 per surface area gives
400e-6 * M / S = 4.03 kg/m = 0.4 g/cm

Polycarbonate density is around 1.2 g/cm so the atmosphere CO2 compressed to the same density would have a thickness of 0.4 / 1.2 = 0.33 cm = 3.3 mm.

The polycarbonate sheets of a typical greenhouse are between 3 and 6mm so 3.3mm of CO2 is quite comparable. Of course, I am not claiming that CO2 and polycarbonate have the same green house effect but the important thing to understand here is that 0.04% of CO2 is not as small as it seems

Comment Re:Trolls (Score 5, Interesting) 404

There are definitely trolls in the flat-earth community and I am pretty convinced that the majority of the 'famous' flat-earthers on Youtube are only doing it for the money. They are scam artists and their target is the myriad of scientifically illiterate people who genuinely believe their crap. Look at all the people who believe in unscientific ideas such as astrology, homeopathy, spiritism, power of crystals, ancient hidden civilizations, ... Add to that the bronze age cosmologies described by the holy books of most religions and you have the perfect environment to bring people to the border of the rabbit hole. Once they are there, Youtube provides the final kick to fall in the hole.

An important factor is the recent resurgence of creationism in the US and in most areas of the world where religious fundamentalists are thriving. Initially, the creationist movement was only targeting the Evolution Theory but all sciences are connected:
- The old ages of Earth and of the Universe are confirmed by Geology, Astrophysics, and Nuclear Physics (i.e. via Radiometric dating) so those sciences MUST be wrong.
- The common ancestry of all life forms is confirmed by DNA analysis, Paleontology and Anatomy so those sciences MUST be wrong.
- The Noah Flood is disproved by History, Geology, Climatology, DNA analysis so those sciences MUST be wrong.
- etc
The end result is that a fundamentalist preacher has no other choices than to denigrate all modern sciences to justify his bronze age beliefs.
Youtube and other social networks are not the cause of irrational beliefs but they provide a good environment to amplify them.

Comment Re:Did you read the summary? (Score 1) 87

The Wolf moon part is absolutely irrelevant since this is just a name given to the full moon in January. The same event in August would be called a Sturgeon Moon Eclipse and in November that would be a Beaver Moon Eclipse.

Also about 1/4 of all full moons can be classified as supermoons (3 or 4 per year) and supermoons are barely noticeable. Finally, there is Total Lunar Eclipses are also quite common (about 1 per year on average) and they are always visible from half of the world. So Supermoon Total Lunar eclipses are really not that rare. That is something that anyone can expect to see once every 10 years.

For instance, the next total lunar eclipses will be 26 May 2021 and it will also be a Supermoon or, if your care about the month names, a Total Flower Supermoon eclipse.

Comment Looks fake even without the rope (Score 1) 43

I did not notice the rope when I first saw the video but the event looked fake to me. The problem is that the trajectory of the robot does not make a lot of sense. It is falling on the side but without any rotation or lateral movement. This is inconsistent with the robot being hit by the moving car.
 

Comment Re: Protection agains close supernovae (Score 2) 76

Thank you! I am now reassured. I was terrified by the prospect of the Great Tribulation but I now know that this won't happen before the next nearby supernova. We know that IK Pegasi - the closest supernova candidate - is too far away to cause us any harm so I can now assume that the Great Tribulation is not due before we approach another candidate so in several millions years. Thanks again! I can go back sinning.

Comment Re:What about the moon? (Score 1) 646

The problem is that there is a minimum speed for any object falling on the Moon or any planet) without being slowed down by an engine or by friction with the atmosphere. If I am not mistaken, that speed is equal to the Escape Velocity. For Earth that is 11.1km/s and for the Moon that is 2.38km/s. This is easy to understand if you consider that any massive object sits at the bottom of a gravity well. The same amount of potential energy is required to enter or exit the well. https://xkcd.com/681/
This is also why dropping ice comets cannot be a viable solution for global warming even if the ice is initially at -273C. The kinetic energy given to that ice (so 11km/s) would be enough to boil it several time. Slowing down the comet with rockets or parachutes would not work either because the same amount of energy would be released in the atmosphere.

Comment Re:Driving (Score 3, Insightful) 184

This is about SELF-DRIVING flying vehicles! Anyways I agree that even without human drivers, this is going to introduce some huge risks. The noise is also going to be problematic. Last but not least, flying requires significantly more energy than driving so this is probably going to be quite expensive. To summarize, I predict that this technology will only be affordable by the wealthiest peoples and that it will have very little effect on the rest of the population (except for the noise).

Comment Re:counting seconds (Score 1) 113

The article explicitly mentions a growth of "one 74 thousandth of a second per year" but the slashdot editors wrote "one 74 thousandth of a second per year". Pfffff...

Anyways, 24h minus 18h41m = 5h19m = 19140 seconds.
For a period of 1.4 billions years the rate of change is 19140 / 1.4e9 = 1.3671e-05 = 1 / 73145 second per year.

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