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Ok, so you set off a massive nuke in space to attract
attention of THEM. However, a big nuke looks a lot
a star. However, if, shortly before you set off the
nuke, you explode a big load of quantum dots, or
fluophores into a big cloud. Now, fluorophores take
and re-emit them as a longer
Quantum dots are hardy, bright examples, and have
particularly tight emission spectra. All highly
properties. Additionally, you can pull some tricks
fluophores, such as using the emission spectra of one
excite a second. Better than this, you can physically
stick them together and they take really short
wavelengths and emit really long ones by passing
electrons along in what's known as Fluorescence
Resonance Energy Transfer (FRET) Meaning you can
a broad spectrum light emitter, such as a candle or
nuclear explosion and remove most of the short
wavelength and really boost the longer wavelengths.
Which should mean you have a great big tight RED
beacon, which should be specific enough to stand out
man made. Also, once you've got the cloud of
dots, you can keep setting off nukes, and indeed it'll
glow all the time (a bit) from the sun.
Inspired by DIYMatt's idea.
[bs0u0155, Dec 25 2011]
[bs0u0155, Dec 25 2011]
Can nano-diamonds be used instead of quantum dots? [againsttheodds, Dec 29 2011]
||Huzzah! A giant signal in an unexpected wavelength is just whats needed. Forget Sagan's prime numbers, massive power in all directions is the thing.
||a really narrow spectrum is just as conspicuous as a prime
number, or sequence of. You just need to be not-like-
other-stars. In fact it'd be (relatively) easy to put a great
spherical cloud around a star. You could call it a Dyson's
Fluoshpere. little more than CdTe dot dust... simple.
||You could use three types of Qdot with emission
wavelengths in the ratio 5:3:1.
||why 5:3:1? I was thinking 3:1:4? Am I being dumb...?
||By 3:1:4 were you thinking of pi? If so, that's
dependent on what base you count in.
||By "5:3:1" I was thinking of the first two primes
(and 1 as a reference). 1:4:9 (first three squares)
could be used, though a nine-fold wavelength
ratio might stretch the limits a bit.
||I'm not sure how "sharp" the emission spectra of
Qdots can be made. Those sold commercially
tend to have half-height widths of maybe 20nm
(which is quite broad), but I do not know if that's
an inherent property of the Qdots, or if simply
down to the control over their growth. But, if it
can't be gotten around, then very fine ratios
would be hard to represent clearly.
||Also, I'm not sure why you'd want to use FRET.
Qdots absorb all the way down to deep UV (and,
presumably, further down), regardless of their
emission wavelength. So, whatever shift you
want, you can get it in a single Qdot or not at all.
||Just one thing- It's "Fluorophore," not "Fluophore."
||But this is a really cool idea! I'm all for innovative
solutions to the METI concept- although there are
still the serious problems inherent to METI to deal
||"Just one thing- It's "Fluorophore," not "Fluophore." I
really, really should know that...