<div dir="auto"><div><br><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Sun, Dec 28, 2025, 7:43 AM John Clark via extropy-chat <<a href="mailto:extropy-chat@lists.extropy.org" target="_blank" rel="noreferrer">extropy-chat@lists.extropy.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><span style="font-family:Arial,Helvetica,sans-serif">On Sat, Dec 27, 2025 at 6:07 PM Ben Zaiboc via extropy-chat <<a href="mailto:extropy-chat@lists.extropy.org" rel="noreferrer noreferrer" target="_blank">extropy-chat@lists.extropy.org</a>> wrote:</span></div></div><div class="gmail_quote"><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><font face="tahoma, sans-serif" size="4"><b><span class="gmail_default" style="font-family:arial,helvetica,sans-serif">>></span>That probably would be good enough
resolution<span class="gmail_default"> for an </span>upload
but unfortunately it was just for one cubic millimeter, the
average human brain contains about 1,<span class="gmail_default">4</span>00,000 cubic millimeters.</b></font></blockquote></blockquote><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div>
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<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">> </span>On the surface, this sounds quite discouraging,</i></font></div></blockquote><div><br></div><font size="4" face="tahoma, sans-serif"><b>It would be very difficult but such a scaling up would not be unprecedented. In August 1942 only one microgram of the element Plutonium had been made, but by August 1945 hundreds of kilograms of Plutonium had been manufactured (and <span class="gmail_default" style="font-family:arial,helvetica,sans-serif">b</span>y 1994 <span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span>111.4 tons had been produced); of course it required a gargantuan factory in Hanford Washington, and $2 billion in 1940s dollars, to do so<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">.</span> <br></b></font></div></div></blockquote></div></div><div dir="auto"><br></div><div dir="auto"><br></div><div dir="auto">In 2020, I did an analysis based on then-available technology and concluded we could scan a human brain in less than ten years at a cost of 2.5 billion. (Since it is a highly parallelizeable task, it could also be done in half that time for twice that cost).</div><div dir="auto"><br></div><div dir="auto"><br></div><div dir="auto">Here is what I wrote:</div><div dir="auto"><br></div><div dir="auto">"The average human brain has a volume of 1.375 liters. When cut into 50 nanometer thick slices, they have a combined surface area of 275 million cm^2 (roughly nine football fields). This area has to be scanned at nanometer-scale resolutions using expensive electron microscopes</div><div dir="auto"><br></div><div dir="auto">A modern electron microscope scanning at a 4 nanometer resolution (the level of detail needed to trace neural circuits) takes 3 hours to process 1 cm^2 of area. To cover the 9 football fields with one microscope would take 94 millennia. Ten thousand microscopes could do the work in 9.4 years, but at a quarter million dollars each, this effort entails an equipment cost of $2.5 billion.</div><div dir="auto"><br></div><div dir="auto">The quantity of data generated in the process is also enormous. At a 4 nanometer resolution, each cm^2 contains (2.5 million × 2.5 million) pixels, about the number of pixels on 750,000 4K TV screens. At one byte per pixel this amounts to 62.5 petabytes of data — three times more data in each square centimeter than all the data held by the U.S. Library of Congress (estimated to be 20 petabytes).</div><div dir="auto"><br></div><div dir="auto">Scanning the 9 football fields of brain tissue at this resolution requires 1.72 zettabytes (10^21 bytes) of data to be collected and processed. This is about the amount of data sent over the Internet in 2019 (1.992 zettabytes according to Cisco’s estimate).</div><div dir="auto"><br></div><div dir="auto">Deriving the human connectome is a herculean task, but a path to the finish line is now in sight.</div><div dir="auto"><br></div><div dir="auto">Many lessons were learned obtaining the fruit fly’s connectome. Researchers found the electron microscope was the main bottleneck. To counter this, they applied parallelization: using multiple electron microscopes at the same time, and using software to digitally stitch together the images they obtained.</div><div dir="auto"><br></div><div dir="auto">The team also found a massive reduction in size from processing the images into a connectome map. The 26 terabytes of raw scanned images, when reduced to a map of neural connections, decreased in size to just 26 MB (a million-fold reduction). A similar reduction in for the human brain into a human connectome would reduce the ~2 zettabytes of images down to a ~2 petabyte connectome.</div><div dir="auto"><br></div><div dir="auto">This is in line with expectations. A petabyte is 10^15 bytes — as many bytes as 10^15 connections in the human brain."</div><div dir="auto"><br></div><div dir="auto"><br></div><div dir="auto">This is an except from a chapter on the direction of technology:</div><div dir="auto"><br></div><div dir="auto"><a href="https://docs.google.com/document/d/1G3vE8L9svX_283r6ZHR2VriiyGrATzvD/edit?usp=drivesdk&ouid=109779696990142678208&rtpof=true&sd=true">https://docs.google.com/document/d/1G3vE8L9svX_283r6ZHR2VriiyGrATzvD/edit?usp=drivesdk&ouid=109779696990142678208&rtpof=true&sd=true</a></div><div dir="auto"><br></div><div dir="auto">Jason </div><div dir="auto"><br></div><div dir="auto"><br></div><div dir="auto"><br></div><div dir="auto"><br></div><div dir="auto"><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div class="gmail_quote"><font size="4" face="tahoma, sans-serif"><b></b></font><br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div>
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<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">> </span>The x-y resolution mentioned was overkill, by at least 10 times, and
the z resolution less so, but still probably higher than necessary.
Let's say it was just about right, though. That means approx. 14
trillion bytes for 1 cubic mm.</i></font><br></div></blockquote><div> </div><font size="4" face="tahoma, sans-serif"><b>I think you could get by with a much much smaller file size because for an upload it doesn't matter what a neuron looks like, what matters is what other neurons it is connected to, which can be described by a list, and how that neuron response to signals received from those other neurons, which can be described by a matrix. An AI would be able to deduce those numbers from the neuron's appearance and save those numbers and discard the now irrelevant <span class="gmail_default" style="font-family:arial,helvetica,sans-serif">i</span>mage information. </b></font></div><div class="gmail_quote"><br></div><div class="gmail_quote"><font size="4" face="tahoma, sans-serif"><b>And I know for a fact that most people have been <span class="gmail_default">vastly </span>overemphasizing the complexity of the brain<span class="gmail_default">. W</span><span class="gmail_default">e</span> know the upper bound of how much information would be required to construct a human brain at the time of birth<span class="gmail_default">,</span> and it's not very large. DNA<span class="gmail_default"> also</span> places an upper bound on how complex a seed AI would have to be. In the entire human genome there are only 3 billion base pairs. There are 4 bases<span class="gmail_default">,</span> so each base can represent 2 <span>bits</span>, there are 8 <span>bits</span> <span>per</span> <span>byte</span><span class="gmail_default">,</span> so that comes out to 750 meg. Just 750 meg, that's about the same amount of information as an old CD disk could hold when they first came out 40 years ago! </b></font></div><div class="gmail_quote"><span style="font-family:"arial black",sans-serif;font-size:large"><br></span></div><div class="gmail_quote"><span style="font-family:"arial black",sans-serif;font-size:large">And that's for an entire human body,</span><span class="gmail_default" style="font-family:"arial black",sans-serif;font-size:large"> </span><span style="font-family:"arial black",sans-serif;font-size:large">only about a third of that</span><span class="gmail_default" style="font-family:"arial black",sans-serif;font-size:large"> 750 meg has anything to do with the brain. And even the stuff that is about the brain, most of it has nothing to do with intelligence, it's just information about metabolism that any cell needs in order to stay alive. </span><span class="gmail_default" style="font-family:"arial black",sans-serif;font-size:large">And </span><span style="font-family:"arial black",sans-serif;font-size:large">the 750 meg isn't even efficiently coded, there is <u>a ridiculous amount of redundancy</u> in the human genome</span><span class="gmail_default" style="font-family:"arial black",sans-serif;font-size:large">. </span></div><div class="gmail_quote"><span class="gmail_default" style="font-family:"arial black",sans-serif;font-size:large"><br></span></div><div class="gmail_quote"><div class="gmail_quote"><div><span class="gmail_default" style="font-family:"arial black",sans-serif;font-size:large">And then there is this: </span></div><div><br></div></div><div class="gmail_quote"><a href="https://www.ox.ac.uk/news/2014-07-25-82-our-dna-%E2%80%98functional%E2%80%99" rel="noreferrer noreferrer" target="_blank"><font face="tahoma, sans-serif" size="4"><b>Only 8.2% of our DNA is functional</b></font></a></div></div><div class="gmail_quote"><span class="gmail_default" style="font-family:"arial black",sans-serif;font-size:large"><br></span></div><font size="4" face="tahoma, sans-serif"><b>And yet that tiny amount of information was enough to reshape the surface of a planet, and enough to make an intelligence that was smarter than itself. Of course I've been talking about the amount of information required to make a newborn baby, I haven't mentioned the all important memory information. Computer scientist Hans Moravec estimated that an adult human has between 1 and 10 TB of memory information. My new iPhone has 2 TB of memory capacity. </b></font><div class="gmail_quote"><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><font size="4" face="georgia, serif"><i><span class="gmail_default" style="font-family:arial,helvetica,sans-serif">> </span>Another factor will be the time needed to scan an entire brain. And there's also the problem of the scanning method dumping heat into the tissue surrounding the area being scanned, potentially messing up the structure and chemical environment.</i></font></blockquote><div><br></div><font size="4" face="tahoma, sans-serif"><b>That wouldn't be a problem if the brain was at the temperature of liquid nitrogen and Aldehyde-Stabilized Cryopreservation<span class="gmail_default"> was used. I'll be damned if I can understand why the hell ALCOR doesn't offer it! </span></b></font><div><font face="tahoma, sans-serif" size="4"><b><br></b></font></div><div><font face="tahoma, sans-serif" size="4"><b><span class="gmail_default">John K Clark</span></b></font></div><div><font size="4"><b><font face="arial, helvetica, sans-serif"><br></font></b></font></div><div><font size="4"><b><font face="arial, helvetica, sans-serif"><br></font></b></font><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div><br></div>
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