[extropy-chat] MBRAIN: Imaging the universe, NOT

[Emlyn O'regan]

Wouldn't we expect MBrains/Advanced civs/whatever to use a system of relays
to observe the universe? If there's a way for local objects to observer the
local environment whilst staying hidden, you'd then beam the results from
relay to relay (how big do these need to be? Tiny?) until they reach the
MBrain. A bit like the mega-scale version of Vinge's localizers.

Emlyn

> -----Original Message-----
> From: Robert J. Bradbury [mailto:bradbury at aeiveos.com]
> Sent: Tuesday, 27 January 2004 9:31 AM
> To: Extropy Chat
> Subject: Re: [extropy-chat] MBRAIN: Imaging the universe, NOT
> 
> 
> 
> On Mon, 26 Jan 2004, Mike Lorrey wrote:
> (in: 
> http://forum.javien.com/XMLmessage.php?id=id::bQ5JCRNB-CUlK-KQ
> lK-W1Eo-a1VrGTkRXiRo)
> 
> > An interesting article by Seth Shostak on space.com:
> >
> > http://www.space.com/searchforlife/seti_shostak_seeing_031120.html
> >
> > details why the hand waving that Robert made recently about 
> the ability
> > of M-Brains to observe the universe should be seriously questioned.
> > reach a curve of diminishing returns.  [snip]
> >
> > Imaging at 1 foot per pixel, small enough to see animals, 
> would reqire
> > a telescope 500 million miles in diameter. Interferometry is of
> > diminishing usefulness, as one would need a 100,000 mile diameter
> > mirror just to catch 1 photon per second at that distance and
> > resolution.
> 
> Interestingly there has been a fair amount of discussion, in 
> part prompted
> by Seth's article, among the non-classical SETI people (SETV, 
> SETIA, probe
> supporters), etc. over the advantages of sending probes back and forth
> (though they are quite small compared to those we now send).
> 
> I would draw your attention to one point -- Seth says "every 
> square foot of
> dino skin would reflect about 10 billion billion photons" -- 
> that suggests
> that he is talking about visible light.  Astronomers already 
> perform IR
> observations and plan to look for planets that way (because 
> planet to star
> signal to noise ratio is better in IR frequencies).  They can 
> also measure
> atmospheric composition with IR spectral emission lines (for 
> ozone, CO2, etc)
> more easily at IR frequencies.  In addition dust is not as 
> big a problem
> at IR frequencies as it is at optical frequencies (which is 
> why the SIRTF
> can look through the dust clouds in star forming regions and 
> through stellar
> nebula for still forming planets).
> 
> So I would not view Seth's comments as a complete 
> show-stopper.  There are
> a range of capabilities one would like to have -- detection 
> of volcanoes,
> detection of forest fires, detection of large buildings, detection of
> atmospheric pollutants (e.g. CFCs), detection of the 
> construction of "hot"
> MBrains in close stellar orbits, etc.  Seth's points do 
> however lead one
> to a conclusion that it may be relatively difficult for ATC 
> to read the
> license plates on distant planets.  But I can live with that.
> 
> Robert
> 
> 
> _______________________________________________
> extropy-chat mailing list
> extropy-chat at lists.extropy.org
> http://lists.extropy.org/mailman/listinfo/extropy-chat
>