HN user
How did this article get past the sugar mafia? That too in nature!
Yudkin [1] must be chortling ;)
Warren Buffett, have your boys been slacking off? Somebody is gonna get really hurt...bad!
In the (is this shape fillable by 1x2 dominoes?) example given by EWD to demonstrate the power of formal reasoning methods, a slight change to the problem statement:
For the shape Q, instead of clipping opposite corners of the 8x8 square board, one (what would lay under a) white square and one black square, which are non-adjacent, are randomly removed.
Real world programming is usually like this, it is hard to cast the problem in the framework of a formal language, like first order predicate logic, and manipulation of uninterpreted formulae (i.e. the problem now mapped into the domain of first order logic) using the rules of first order logic might not lead to anything useful.
It seems to me that EWD is showcasing some example programming problems that are elegantly handled by his formal proof techniques, while ignoring the vast swathes of programming problems that might not be well handled by these techniques.
@dukeyukey, from these '_lot_ of studies', if we remove those that are directly or indirectly funded by the coffee lobby, are we left with the empty set ∅ ?
@clumsysmurf, nice catch!
Could it be possible that the coffee lobby is behind this 'counter'-study?, since a relatively simple inference from the OP has catastrophic consequences for the coffee business:
Deep sleep is necessary for the slow electrical waves that clear the brain of waste including amyloid proteins. (Excessive) coffee intake reduces the quality and quantity of deep sleep, thus leading to a build up of waste products including amyloid, resulting in cognitive declines such as Alzheimer's etc. Therefore, coffee intake (indirectly) causes Alzheimer's.
Admitting that last part is suicidal for the coffee business.
That person must have never heard of Isaac Newton's First law of motion.
No, that is why the hedge fund is begging.
Paraphrasing from the article:
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a kilogram of gasoline gives you about 13 kWatt-hrs,
a kilogram of coal a little less, about 8 kWatt-hrs,
a kilogram of lithium ion battery can store only 0.2 kWatt-hrs, and,
a kilogram of water at 1 km altitude is just 0.0027 kWatt-hrs.
On the other hand,
a kilogram of Uranium 235 gives you 24000 kWatt-hrs!! There’s a lot of energy in Uranium 235!
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So, barring antimatter, U235 is the ULTIMATE BATTERY.
Most fusion research seems to be focused on fusing the lightest elements, usually isotopes of hydrogen: deuterium and tritium and occasionally lithium to produce energy.
I wonder how much research has been done on the fusion of heavy elements such as lead (Pb)? If it were possible to reverse the fission of U235, i.e., fuse the fission end products such as Pb back into U235 in an energy efficient manner, and with a very low carbon footprint [1], that would solve the energy storage problem.
[1] Also from the article: "CO2 emissions resulting from current storage technologies range from 104 to 407 kg per Mega Watt-hour of delivered energy. Compare this with coal, which releases almost a 1000 kg of CO2 per Mega Watt-hour produced. " This is the CO2 emissions created in the construction and maintenance of the energy storage facility averaged over the total energy stored and delivered during its lifetime.