[ExI] Uploads as a group of AI agents

[John Clark]

On Sun, Mar 29, 2026 at 1:16 PM Keith Henson <hkeithhenson at gmail.com> wrote:

*>> Forget 1/3 c, if just one ET had been able to send just one Von Neumann
>> probe at 1/30 c then almost instantly (cosmically speaking) it would be
>> very obvious to anybody that the Milky Way had been engineered, but instead
>> we see a huge astronomical number of energy rich photons from hundreds of
>> billions of stars radiating uselessly into empty space; and the Milky Way
>> is not unique, even our largest telescopes can find no sign that any other
>> galaxy has been engineered either. That's why I think the evidence is
>> overwhelming that we are the only intelligent beings in the observable
>> universe. [...]  I** don't think the dimming of Tabby's Star, or that of
>> any other similar star, has anything to do with ET. *
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> * > You may be right.  The odds are astronomical against there being a
> technological civilization spreading out when and where we can see it. But
> it is not aliens; we need to figure out what is causing light dips in a
> cluster of stars a thousand light-years in diameter.  Got any ideas? *


*As I've mentioned before, for several years now the scientific community
has reached an overwhelming consensus that the dimming is caused by dust
and a few larger fragments. *


> * > All of those proposed have physical or logical problems.  For example,
> dust clouds.  A dust cloud would be blown out ot the system by light
> pressure like a comet tail,*


*Light pressure can blow away a comet's tail because that tail cloud is so
tenuous it would be considered one of the best vacuums ever produced if it
had been made in a physics laboratory on earth; the scientific community is
talking about a dust cloud that is many thousands of times denser than
anything a comet can produce and is far too massive to be dissipated by
light pressure.  *


> *> and the chances of us seeing such a transitory event are very low for
> one star,*


*Astronomers have photographic plates of tabby's star going back to the
late 1800s indicating that the star is about 14% dimmer now than it was
then, how much before that the star started to act strangely is
unknown, but we do know that today we observe that the dimming is greater
in the optical range than the infrared range. Exactly what you would expect
of a dust cloud. And we also observed that on top of the gradual dimming we
also see, at irregular intervals, much greater decreases in brightness that
are of very short duration and occur at irregular intervals. Exactly what
you would expect for a star that was inside a dense dust cloud that
contained large solid fragments in chaotic orbits .*

*>not to consider a couple of dozen.*
>

*Stars in very dense dust clouds are not rare, they have been observed many
millions of times, and even more often since we've been able to deploy good
infrared telescopes because infrared light can make its way through more
dust than optical light can. The only thing unusual about tabby's star is
that its dust cloud is more lumpy than most, but that's what you would
expect if a few thousand years ago a small planet got too close to the star
and was torn apart by tidal forces into dust and solid fragments with
chaotic orbits.  *

*Ten years ago it might've been higher but today if I was making a list of
cosmic mysteries I would place tabby's star very low on that list. *

*John K Clark*
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