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Old 2013-08-20, 16:53   #991
firejuggler
 
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new exoplanet: molten lava, 8.5 hours year, tidally locked

http://arxiv.org/pdf/1305.4180v2.pdf
and more readable http://www.slate.com/blogs/bad_astro...hour_year.html
climate change, much?

Last fiddled with by firejuggler on 2013-08-20 at 16:53
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Old 2013-08-20, 18:40   #992
xilman
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Quote:
Originally Posted by kladner View Post
I love the tail section!
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Old 2013-08-20, 20:53   #993
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I love the tail section!
Absolutely!
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Old 2013-08-20, 22:10   #994
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Scientists Achieve On-Demand Quantum Teleportation For The First Time

Controlled Tornadoes Create Renewable Energy
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Old 2013-08-21, 02:53   #995
LaurV
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Quote:
Originally Posted by xilman View Post
Just occasionally, you do get what you pay for.
I own an RX510 for years, at the time I paid more then for a good desktop computer for it. This box can scan, print high-res photos, etc. It is a wonderful machine, with separate ink cartridges, except that the ink cartridges have a chip saying how much ink there is inside. This chip is not connected to anything inside of the cartridge, it is just a small PCB stuck on the exterior PLASTIC wall of the cartridge. There is no way that the small PCB can "detect" in any way what qty of ink is inside. This "chip" contains a small eeprom on it, and that is all. Some values are written into it by the printer, any time you print. The "brain" of the printer evaluates how much ink of each color you use for each page, and evaluates the remaining quantity. This is a very exact (deterministic) process.

The printer then shows the qty of ink remaining, but not the real one; it shows the one indicated by the chip. The real one nobody knows it, you can't see inside of the box. After a while it says "empty" in spite of the fact that there is still ink inside, which you can feel if you take the cartridge out and shake it. When it says "empty", the printer doesn't print anymore (it notifies you before, so you prepare a new cartridge in advance) and you have to change it, therefore throwing into the rubbish bin about 10, 20, 30% or more of the total bought ink. Because the manufacturers they always fill a little bit more, it is better then being really out of ink when you desperately need to print that report, and the printer saying nothing about (or saying that you are still half full).

So, all the quest is for that "additional ink", which is sometime a lot, and it costs a lot of money.

The first thing I bought next day after the printer, was a cartridge resetter, for which I paid 120 baht (about $4 US dollars), it has a small Atmel MCU on it and some spring-pins that have to contact with the cartridge, and two small LR41 button batteries (which I replaced once and paid 35 baht for each). That resetter was one of the best investments I ever did, it recovered its money multiple times!
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Old 2013-08-21, 03:33   #996
ewmayer
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A Black Hole Mystery Wrapped in a Firewall Paradox
Quote:
Things got more interesting, however, in 1974 when Stephen Hawking, the British cosmologist, stunned the world by showing that when the paradoxical quantum laws that describe subatomic behavior were taken into account, black holes would leak particles and radiation, and in fact eventually explode, although for a hole the mass of a star it would take longer than the age of the universe.
This was a breakthrough in combining general relativity, the gravity that curves the cosmos, with quantum theory, which describes the microscopic quirkiness inside it, but there was a big hitch. Dr. Hawking concluded that the radiation coming from a black hole would be completely random, conveying no information about what had fallen into it. When the black hole finally exploded, all that information would be erased from the universe forever. “God not only plays dice with the universe,” Dr. Hawking said in 1976 in a riposte to Einstein’s famous doubts about the randomness of quantum theory, “he sometimes throws them where they can’t be seen.”

Particle physicists cried foul, saying that this violated a basic tenet of modern science and of quantum theory, that information is always preserved. From the material in the smoke and flames of a burning book, for example, one could figure out whether it was the Bible or the Kama Sutra; the same should be true of the fizz and pop of black holes, these physicists argued. A 30-year controversy ensued.
Bizarrely, the article blathers at length about the particle physicists' take on information theory, which appears to be dominated by the reversibility of "individual quantum transaction", i.e. the microscopic view. Larger-scale-systems, the transition from micro to macro, collective behavior, and that obscure curiosity known as the "Second Law of thermodynamics" get 0 mention.

The hypothesis of exact information preservation appears to me to be demonstrably false - to give an example "close to home", I did my PhD in fluid dynamics, where much time is spent on the physics and maths of shock waves. Those have the interesting property, not dissimilar to a kind of no-hair principle, that once the flow goes through the shock, fundamental details about the inputs are lost forever. In other words, the detailed input state which gave rise to the shock can be recovered exactly only up to the shock. Physically this is reflected in the entropy jump across the shock. Mathematically this is reflected in the coalescence of characteristics - roughly speaking, paths along which information propagates - at the shock.

If the quantum boys want to argue that Boltzmann was wrong, they'll need better than to merely assert that "information is preserved" - because information destruction is occurring all around us, all the time. The aforementioned 2nd law and all that. Sure, much about the the transition from the realm of "exact" QM to the "lossy" macro world remains mysterious ... cue discussion of time's arrow.
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Old 2013-08-23, 00:10   #997
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Quote:
Originally Posted by ewmayer View Post
Speaking of black holes:
http://www.ibtimes.com/what-are-ocea...atlantic-ocean
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Old 2013-08-24, 18:00   #998
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http://www.lohdownonscience.org/a-ma...e-to-infinity/

Listen to the audio, left side of page.
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Old 2013-08-24, 21:40   #999
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Quote:
Originally Posted by Uncwilly View Post
http://www.lohdownonscience.org/a-ma...e-to-infinity/

Listen to the audio, left side of page.
that is a great site in general, thanks!
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Old 2013-08-26, 20:40   #1000
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Rota's Conjecture: Researcher solves 40-year-old math problem
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Old 2013-08-27, 19:53   #1001
xilman
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Default More evidence for Uup

Further evidence for element 115.
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