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Comment: The assumption here... (Score 3, Interesting) 210

by exp(pi*sqrt(163)) (#27699251) Attached to: Using Light's Handedness To Find Alien Life that life forms a kind of amplification process.

If you have some random soup of molecules formed by abiotic processes then apart from some small biases brought about by parity-violating fundamental physics we expect complete symmetry between left- and right-handed molecules.

But life, arguably, forms a kind of amplification process. Competition between molecules with different chirality might serve to increase any initial small difference between one group and another. So what starts as almost exact symmetry results in a planetwide bias one way or the other.

But there are two issues.

(1) Could such a planetwide bias show up strongly enough in the polarisation of light reflected from the planet. It seems very unlikely given how messy a planet is. Let's say you pick a million different types of molecule than come in chiral pairs and for each molecule pick one of the pair, discarding the other. Now jumble up many different copies of each of these molecule types. Your chances of detecting chirality from afar is minimal even though, in some sense, the mixture is perfectly chiral, because of the overall randomness of the mixture.

(2) Could any other physical processes cause such amplification? The answer is yes. For example some kinds of crystal growth can result in homochirality.

So I'm pretty sceptical despite the idea being neat.

Comment: Re:I can live with it (Score 1) 640

by exp(pi*sqrt(163)) (#27345731) Attached to: Why Fear the End of the R-Rated Superhero Movie?

> OTOH, we don't even start to become sexual beings until the early teen years.

Presumably you weren't ever a child. Or you've repressed the memory. I'm constantly amazed when I hear about parents who are surprised when their almost newborns get erections and when kids of 3 or 4 discover it's fun to play down there. Certainly by time I was 9 I'd figured out there was a connection between all that and seeing girls in underwear and I wasn't too smart at figuring those kinds of things out.

Comment: Re:Yes, always. (Score 1) 852

by exp(pi*sqrt(163)) (#27303423) Attached to: Battlestar Galactica Comes To an End
Who said that the character sometimes called 'God' in BSG is all powerful and all knowing? Well...maybe Baltar said it. But who said that Baltar's religion was in any way a representation of the truth? He clearly didn't believe it. Don't spoil a good story by bringing in Christian baggage. This is not a Christian story.

Comment: Lost opportunity (Score 1) 148

by exp(pi*sqrt(163)) (#27057791) Attached to: The Finns Who Invented the Graphical Browser

> Otherwise, the Web revolution might have begun a year earlier.

OMG! You mean I could have been using myspace a year earlier and I'd have twice as many friends by now?! We could have had lolcats twelve months earlier and my application in the lolcat programming language would already be finished?! It's like a year of my life has been stolen. Who do I sue?

Comment: Re:not quite a first, guys (Score 1) 255

by exp(pi*sqrt(163)) (#26933637) Attached to: Human Eye Could Detect Spooky Action At a Distance

Yup. Two systems are entangled if their joint state is not simply the product of their individual states; which is generally the case for humans that have any shared history.

Ironically, when people publish papers about entangled systems they're usually talking about systems that are entangled in some particularly simple way that's easy to prove theorems about. But real people are more entangled than a galaxy sized bowl of spaghetti.

IF I HAD A MINE SHAFT, I don't think I would just abandon it. There's got to be a better way. -- Jack Handley, The New Mexican, 1988.