[ExI] Scientists Discovered ?Mini-Computers? in Human Neurons?and That?s Great News for AI

Stuart LaForge avant at sollegro.com
Mon Jan 20 19:38:35 UTC 2020

Quoting John Clark:

> *> Seems like it should be a testable hypothesis.*
> It is. You gave the formula for the minimum amount of energy needed to
> erase one bit of information in your last post, just plug in the numbers
> for body temperature and the formula will give you a ridiculously small
> number, a number that remains ridiculously small even if you multiply it by
> 86 billion (the number of neurons in the human brain) and then multiply it
> again by 15,000 (the maximum number of dendrites any neuron has been
> observed to have).

I am not disputing this, but Landauer's main point, and consequently  
mine, was that information is physical because it costs energy to  
erase. This remains true regardless of whether the amount of energy  
being used is near the limit or trillions of times more than it. You  
are right, the limit itself is unimportant to biology. But, the  
equivalence of information and energy implied by the limit is  
important in considering why the brain uses more energy than any other  
organ including the heart. Which is surprising since the heart is of  
similar mass and does literal physical work schlepping blood from your  
feet to your head and back every minute of every day.

> Biologists would do well to spend their time studying things other  
> than Landauer, it just isn't important for there subject.

The Landauer limit might not be important to biologists but Landauer's  
central thesis that information costs energy to process and is in some  
sense equivalent to energy certainly is. It is probably no accident  
that the cell's energy currency ATP is also one of the building blocks  
of nucleic acids which directly encodes information.

Do you dispute information-energy equivalence?

Stuart LaForge

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