[ExI] Von Neumann Probes

[Jason Resch]

On Wed, Jan 28, 2026, 8:39 AM John Clark <johnkclark at gmail.com> wrote:

> On Wed, Jan 28, 2026 at 7:40 AM Jason Resch via extropy-chat <
> extropy-chat at lists.extropy.org> wrote:
>
> *> Earlier you insisted energy consumption (i.e. power) was all important
>> for running non-reversible computations (which it is).*
>
>
> *Yes.*
>
>
>> *> And this was your reason for concluding it was obvious ETI would build
>> Dyson swarms.*
>
>
> *Yes.*
>
>
>> * > Now, when I show there were better ways, you seem to forget this, *
>
>
> *You are absolutely correct, I have forgotten that. I don't know what
> you're talking about.*
>


Answer my question from my previous email: how many non-reversible
computations can be performed for two computers at those two temperatures,
for a given expenditure of energy. If you attempt to answer this then you
will know exactly what I am talking about, but you won't because you have
an inability to admit making mistakes or being wrong.

Jason


>
> *> and retreat to citing an unrelated fact we all agree on.*
>
>
> *So we both now agree that your comment about Black Holes improving the
> efficiency of a solar heat engine by many billions of times was silly?  *
>
> *> I have to conclude you're just trolling at this point*
>
>
> *Just a few days after I first joined this list in 1993 I was accused of
> being a troll, so I guess I'm the oldest living troll in the world.*
>
* Either that or the accusation of being a troll is the only rebuttal that
> somebody can think of.  *
>
> * John K Clark*
>
>
>
>
>
>
>
>
>
>
>>>>
>>>>>> *> Ite not a "slight improvement." It's an efficiency improvement of
>>>>>> many billions of times. Even a small black hole (a few meters across, with
>>>>>> the mass of Jupiter) is 10^-8 degrees, so close to a billion times colder
>>>>>> than background radiation. A galactic center black hole can be a trillion
>>>>>> times colder than the background radiation. So it is not a "slight
>>>>>> improvement in efficiency," it's equivalent to being able to perform
>>>>>> billions or trillion of times as many non-reversible computations for the
>>>>>> same expenditure of energy.*
>>>>>>
>>>>>
>>>>> *Nope, you'd barely increase the efficiency at all. The Carnot
>>>>> Efficiency (X) depends entirely on the temperature of your heat source (Th)
>>>>> and your cold sink (Tc), formula is: *
>>>>>
>>>>> *X=1- Tc/Th*
>>>>>
>>>>> *The surface of the sun is at 5,800 K and the CMBR is at 2.7K, and
>>>>> you're right that a Black Hole with the mass of Jupiter would have a
>>>>> temperature of about **10^-8 K, so let's plug in some numbers: *
>>>>>
>>>>> *If we use the CMBR as the cold sink then*
>>>>>
>>>>> *X= (1-(2.7/5800) = 0.99353 efficiency *
>>>>>
>>>>> *If there was something that was just twice as efficient then you'd
>>>>> have something that was nearly 200% efficient, in other words you'd have a
>>>>> perpetual motion machine. And you were talking about something that was
>>>>> many billions of times more efficient.   *
>>>>>
>>>>>
>>>>> *Now let's look at what would happen if we used a Jupiter mass black
>>>>> hole for the cold heat sink:*
>>>>>
>>>>> *X = 1 - 0.00000001/5,800 = 0.9999999999983 efficiency *
>>>>>
>>>>> *To summarize, if you use empty space as your cold heat sink you'd
>>>>> only lose about 0.047% of your energy, and I think that's pretty damn good.
>>>>> If you use a Jupiter size black hole as your cold sink you'd lose about
>>>>> 0.00000000017% of your energy. Doesn't  seem worth all the trouble to me,
>>>>> and I wonder where you'd get the vast amount of energy necessary to
>>>>> compress Jupiter into a black hole. I think ET should be more concerned
>>>>> with trillions upon trillions of suns radiating all that nice juicy energy
>>>>> uselessly into infinite space. *
>>>>>
>>>>
>>>> *> Now work out the number of non reversible computations that can be
>>>> performed under the two efficiencies you calculated.*
>>>>
>>>
>>> *The maximum number of bits any physical object can compute depends on
>>> how massive it is. No computer, regardless of its serial or parallel, can
>>> compute more than 1.36*1^50 bits per second per kilogram.*
>>>
>>
>> You are avoiding my question.
>>
>> Earlier you insisted energy consumption (i.e. power) was all important
>> for running non-reversible computations (which it is). And this was your
>> reason for concluding it was obvious ETI would build Dyson swarms.
>>
>> Now, when I show there were better ways, you seem to forget this, and
>> retreat to citing an unrelated fact we all agree on. I have to conclude
>> you're just trolling at this point, or suffering some severe form of
>> cognitive dissonance.
>>
>> Jason
>>
>> P.S.
>> You have also forgotten the 4X improvement over Bremmermann's limit as
>> shown by Margolus and Levitin, which you earlier acknowledged when you said
>> "4E/h"
>>
>>
>>
>>> *John K Clark*
>>>
>>>
>>>> _______________________________________________
>> extropy-chat mailing list
>> extropy-chat at lists.extropy.org
>> http://lists.extropy.org/mailman/listinfo.cgi/extropy-chat
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.extropy.org/pipermail/extropy-chat/attachments/20260128/c978e068/attachment.htm>