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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?

Comment Re:Hey guys, seriously. (Score 1) 286

The 1930s technocracy movement outlined a society without money, thinking that it and "The Price System" inevitably lead to overconsumption and collapse. They suggested replacing it with energy chits equally distributed among the population, valid for one year to prevent debt accumulation.

http://www.technocracy.org/study-guide

Comment Re:Let us opt out. (Score 1) 326

Lyndon Johnson started the shenanigans with his "unified budget" that included trust funds not subject to budgetary legislation, and over the years Congress used the concept for further obfuscation (such as pinning automatic budget cuts to the unified budget rather than the actual budget).

I have no idea what the current situation is, but the SS trust funds were officially off-budget as of 2005 according to http://www.ssa.gov/history/BudgetTreatment.html

"present law mandates that the two Social Security Trust Funds, and the operations of the Postal Service, are formally considered to be "off-budget" and no longer part of the unified federal budget."

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