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Comment Re:9.999... -- 0.999... = 9 ? (Score 1) 1260

It depends on the infinity you're talking about. You can use something like mathematical induction to demonstrate 9.999... - .999... = 9

9 - 0. = 9
9.9 - .9 = 9
9.99 - .99 = 9
9.999 - .999 = 9
etc. Is there any finite number of 9s you can tack on to make this not true? No- and there's no reason an infinite number of them will make any difference to it.
  9.99999...
-0.99999...
=9.000000...

Or,
9 + ( .9 + .09 + .009 ... ) - (.9 + .09 + .009 ...)
Algebraically rearranged- you CAN do this:
9 + (.9 - .9 ) + (.09 - .09 ) + (.009 - .009 ) ... = 9

Comment Re:This is just faulty math (Score 1) 1260

How can you multiply pi by anything at all? After all, not only does it have an infinite number of digits, we don't even know what they all are!
How can you multiply 1/3 by anything at all? 1/3 = .333...
How can you multiply 1 by anything at all? After all, 1 = 1.000000... which is an infinite number of 0s.

Comment Re:This is second place (Score 1) 1260

.999... is not an infinite number. It's finite in the same way pi is finite, and 10*pi - pi = 9*pi. It's a decimal expression of an infinite series, though.

9 + 9/10 + 9/100 + 9/1000 + ... - 9/10 - 9/100 - 9/1000 ...

Everything after 9 cancels out (9/10 - 9/10, 9/100-9/100...) so you get 9 exactly.

Comment Re:Fascinating Proposition (Score 1) 480

I read about a study where they hooked a guy up to sleep monitors, and whenever he looked like he was going into REM sleep they'd poke him or play a noise or something, just enough to get him out of REM sleep. He'd wake up in the morning feeling well-rested, but exhibited a lot of the same symptoms as someone seriously sleep deprived.

Comment Re:Fascinating Proposition (Score 1) 480

Out of curiosity, what would a proper electronics geek do to find one/disable of those things if he knew it was in the room- short of tearing everything apart? Is it possible to rig up some sort of detector that could find it- or some sort of electromagnetic interference that could kill it without, say, setting off a small nuclear bomb?

Comment Re:Don't Hold Your Breath (Score 1) 105

Yeah, I know how (cosmologically speaking) distance = time, I just meant that they're saying alpha varies in space as well. From the article:
"Along one direction the fine-structure constant, which governs the strength of the electromagnetic force, grows slightly weaker with time, while in the other direction it grows slightly stronger. " ... which seems to suggest that the entire universe has some sort of axis along which alpha changes.

Comment Re:cost (Score 1) 148

The point being, Moore's Law has had 15 years to work and if someone was selling you a PC from 15 years ago for the same price as it cost 15 years ago, you'd be a bit confused.

"It's 150 Mhz with a WHOLE GIGABYTE of RAM! $1300, with included copy of Windows 98!"

Comment Re:Why not just use Pinyin? (Score 1) 508

Per wikipedia, it sounds like Anglo-Norman didn't supplant English.

"Although the English language survived and eventually eclipsed Anglo-Norman, the latter had been sufficiently widespread as to permanently affect English lexically. This is why English has lost or, more often, kept as parallel terms many of its original Germanic words which can still be found in German and Dutch. Grammatically, Anglo-Norman had little lasting impact on English, although it is still evident in official and legal terms where the noun and adjective are reversed: attorney general, heir apparent, court martial, body politic, and so on.[2]"

In other words, modern English isn't a descendant of Anglo-Norman.

Comment Re:Hah, more profits for publishers (Score 1) 226

I'm not saying that oligopolies set prices based on supply and demand, or that oligopolies don't set prices higher than in a market with perfect competition. But that's not the definition of a free market.

A free market is a market without economic intervention and regulation by government except to enforce ownership ("property rights") and contracts.

http://en.wikipedia.org/wiki/Free_market

As I understood Microeconomics 101, an oligopoly usually sets prices lower than a monopoly, but higher than a market with monopolistic competition or perfect competition. An oligopoly is not effectively a monopoly, and behaves quite differently. I think you're confusing a "free market" with a monopolistically competitive or perfectly competitive one.
FYI, trains are a "natural monopoly", I think, not an oligopoly, and for that matter the government owns AmTrak. So yes, not a free market at all.
Again- I'm not saying oligopolies are good for the consumer, but they can quite easily exist in a free market- so can monopolies. That's why most of the world's more sane governments have laws preventing certain types of anticompetitive behavior and restricting the free market.

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