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Comment Re:Can someone explain this theft? (Score 1) 232

Isn't the history of a bitcoin included in the block chain? And the stolen bitcoins identifiable?

If so whoever tries to use one risks being traced, moreover the recipient could be considered as knowingly accepting stolen goods..

Sort of like the haul from a bank robbery having an indelible "This money stolen from Bank X" printed on every bill.

Submission + - WhatsApp Founder used Nonchangable Airline Ticket to Pressure Facebook (flyertalk.com) 1

McGruber writes: In a post on the Flyertalk website (http://www.flyertalk.com/forum/22387891-post72.html), WhatsApp Founder Jan Koum provides another interesting detail about how he steered Whatsapp into a $16 Billion Deal with Facebook (http://mobile.slashdot.org/story/14/02/20/1344218/how-jan-koum-steered-whatsapp-into-16b-facebook-deal):

we announced the deal with Facebook on wednesday after the market closed. during the process, we realized there was a chance we might not be able to get the deal wrapped up and signed on wednesday and it could delay. when the risk of the delay became real, i said: "if we don't get it done on wednesday, it probably wont get done. i have tickets on thursday to fly out to Barcelona which i bought with miles and they are not easily refundable or even possible to change. this has to be done by wednesday or else!!!" ...and so one of the biggest deals in tech history had to be scheduled around my M&M award ticket


Comment Re:idle time (Score 1) 533

The idle loop is alive and well in embedded systems. In some cases energy use is minimized by using a slow clock chosen for some small fraction of idle time, in others by sleeping between bursts of fast processing.

x86 idle power reduction under unix started sometime in the late 1990s
https://blogs.oracle.com/bholler/entry/the_most_executed_code_in

Other OS starting using it around 2000
http://en.wikipedia.org/wiki/System_Idle_Process

Thus seti@home launched in 1999 could legitimately claim it made use of otherwise wasted CPU cycles on the Mac and Windows 95 clients.

Comment Re:ethics of killing and warfare (Score 3, Interesting) 153

Moral killing may not be that hard to define. Convert the three laws of robotics into three laws of human morals by taking them in reverse order:

1) Self-preservation
2) Obey orders if no conflict with 1
3) Don't harm others if no conflict with 1 or 2

To be useful in war an AI would have to have to follow those laws, except that self-preservation would apply to whichever human overlords constructed them.

Comment Re:Vacuum (Score 1) 332

I confess to being stupid but endeavor to learn. Your blind spot seems to be the assumption that in equilibrium the radiation from an object must re-emit the same energy per Hz as acquired from the absorption spectrum. Classical thermodynamics, while powerful, leads to an incomplete picture. Statistical thermodynamics says the incoming energy is rapidly randomized among probable states (fortunately for life some of those may start the electron transport chain). The excess energy populates an increasing number of available states until enough of them dissipate (or in vacuum radiate) the excess energy away. Which has very little connection with some hypothetical temperature of the incoming radiation.

Comment Re:Vacuum (Score 1) 332

In thermal equilibrium with the environment, not with each other. An object absorbing more high frequency radiation has to get hotter to radiate that energy at the lower frequencies. Thus any measurable temperature is a property of the object, not the radiation field. You could define the temperature of vacuum as that of a gray body in equilibrium with the local radiation if that makes you happy. Not sure how useful such a definition would be.

Comment Re:Vacuum (Score 2) 332

A thermometer coating with high absorption for solar wavelengths and low emissivity at longer wavelengths would get hotter than one with the opposite characteristic when placed near the Sun. Indeed you could run a heat engine off this temperature difference and as you say it would ultimately be powered by the continuing incident radiation. But the vacuum environment has no inherent temperature of its own, rather a radiation flux which can heat different objects to different temperatures even when both are in thermal equilibrium.

If you enclose a vacuum in a black box with walls at 1 kelvin what is the temperature of the vacuum? If you heat one wall to 5000 kelvin what is the temperature of the vacuum? Is there a gradient? Does it become anisotropic and depend on the orientation of the thermometer?

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