Using AI to further debunk ancient Egyptians used technologies to drill granite far beyond the current level.

[sjastro]

I was going to include this in my ongoing thread on AI learnt "something" from the Physical & Life Sciences Forum highlighting the progressive improvement in AI over the past year but decided on a new thread as it pertains to an issue raised in the Where are the current ripples from Noah's Flood? thread.
The issue relates to Petrie’s No. 7 granite core sample which is somehow considered as evidence the ancient Egyptians had access to granite cutting technology way beyond the capabilities of modern equipment.

Before proceeding astronomers do not directly measure angular separation or angular diameters of objects such as double stars or planets as they did in the old days using devices such a visual micrometer, instead they image the object and use software to accurately measure the pixel separation.
By knowing the image scale, they are able to convert pixel separation into angular distances which are far more accurate than the old methods.

One of the problems in the thread there was not enough information on the pitch or separation of the groove lines in Petrie’s sample.

I assigned the task to GPT-4o to extract information from the image on the pitch in the image corresponding to each turn or 360⁰ rotation of the tool.
It proceeded as follows.

(1) Enhance the image contrast to make the groove lines more visible.
(2) Analyse the image for the number and size of pixels.
(3) Measure the pixel separations of the grooves.
(4) The next step GPT-4o required information from me, I used Dunn’s average pitch value of 0.1”.
(5) Average the pixel separations and use the conversion S = (Average pitch in inches/Average pixel separation) = 0.1/15 = 0.00667”/pixel which is the image scale.
(6) Convert pixel separation to pitch using the image scale.
(7) Calculate the average pitch value and the standard deviation (%).
(8) Plot pitch against turn number and perform a quadratic polynomial regression of degree 2 to find the curve of best fit.

The next post is comparing the Petrie data extracted by GPT-4o to tolerances for pitch when drilling granite using current technology of diamond tipped drills with RPMs in the range of 1000-6000 RPM depending on the core size of the granite.

 

[sjastro]

Information of pitch data extracted by GPT-4o.

The mean and standard deviation for pitch on Petrie's sample was found to be as 0.095” ± 24.66%.

Comparing this value to tolerances that would be expected using modern equipment.

The Petrie sample has a diameter of around 4.5" hence the pitch tolerance is around ±3% if it was drilled using modern equipment.
The pitch measurements on the sample fall well outside industry standards while statistically the standard deviation is 8X worse than the tolerance level.
One would have expected this super technology well beyond how current capabilities would produce more consistent pitch values yet the explanation is far more simple the ancient Egyptians used copper tube and sand as an abrasive cutter with a flywheel attached to a bow drill.

Since this thread is about AI, the next post is the Python code generated by GPT-4o when analyzing the Petrie sample.

 

[sjastro]

GPT-4o's Python code.

 

[SelfSim]

I was going to include this in my ongoing thread on AI learnt "something" from the Physical & Life Sciences Forum highlighting the progressive improvement in AI over the past year but decided on a new thread as it pertains to an issue raised in the Where are the current ripples from Noah's Flood? thread.
The issue relates to Petrie’s No. 7 granite core sample which is somehow considered as evidence the ancient Egyptians had access to granite cutting technology way beyond the capabilities of modern equipment.

Before proceeding astronomers do not directly measure angular separation or angular diameters of objects such as double stars or planets as they did in the old days using devices such a visual micrometer, instead they image the object and use software to accurately measure the pixel separation.
By knowing the image scale, they are able to convert pixel separation into angular distances which are far more accurate than the old methods.

One of the problems in the thread there was not enough information on the pitch or separation of the groove lines in Petrie’s sample.

View attachment 357695​

I assigned the task to GPT-4o to extract information from the image on the pitch in the image corresponding to each turn or 360⁰ rotation of the tool.
It proceeded as follows.

(1) Enhance the image contrast to make the groove lines more visible.
(2) Analyse the image for the number and size of pixels.
(3) Measure the pixel separations of the grooves.
(4) The next step GPT-4o required information from me, I used Dunn’s average pitch value of 0.1”.
(5) Average the pixel separations and use the conversion S = (Average pitch in inches/Average pixel separation) = 0.1/15 = 0.00667”/pixel which is the image scale.
(6) Convert pixel separation to pitch using the image scale.
(7) Calculate the average pitch value and the standard deviation (%).
(8) Plot pitch against turn number and perform a quadratic polynomial regression of degree 2 to find the curve of best fit.

The next post is comparing the Petrie data extracted by GPT-4o to tolerances for pitch when drilling granite using current technology of diamond tipped drills with RPMs in the range of 1000-6000 RPM depending on the core size of the granite.

GPT-4o is clearly the product of the mainstream academic intelligentsia and is therefore incapable of passing the mighty, extolled 'pub-test'.

We take your GPT-4o analysis and raise it by Petrie/Dunn etal's going-in, (presumed), spiral pattern, their vastly superior string test, followed up by the ultimate and awesomely, mighty pub-test!

On a more serious note though, I cannot escape admiration and feelings of awe at the artistry/skills and sheer committment of those individuals who must have actually produced these megalithic works.

PS: Thanks to all contrbutors to that last thread .. I was lurking and eagerly awaiting each counter-argument to the mainstream position. It was a fascinating thread!

 

[sjastro]

GPT-4o is clearly the product of the mainstream academic intelligentsia and is therefore incapable of passing the mighty, extolled 'pub-test'.

We take your GPT-4o analysis and raise it by Petrie/Dunn etal's going-in, (presumed), spiral pattern, their vastly superior string test, followed up by the ultimate and awesomely, mighty pub-test!

On a more serious note though, I cannot escape admiration and feelings of awe at the artistry/skills and sheer committment of those individuals who must have actually produced these megalithic works.

PS: Thanks to all contrbutors to that last thread .. I was lurking and eagerly awaiting each counter-argument to the mainstream position. It was a fascinating thread!

I have been trying to contact you, can you send a PM to make sure this is possible?
Here is the ultra advanced technology Chris Dunn has been using to measure the pitch on Petrie's sample.

​

Gizapower - The Petrie Museum 1999 - Chris Dunn VI

You would think he would try using a vernier gauge instead of string, sticky tape and a ruler, even then it is no easy task in lining up the callipers on the grooves to make reproducible measurements.
According to his "measurements" (not sure how many he performed) the Egyptians could produce a pitch in the range of 0.110" - 0.120" whereas on the 52 calculations made by GPT-4o, the range was 0.070" - 0.147".

 

[SelfSim]

I'm also left wondering how these guys established the actual date this core was drilled?

I mean, how did they eliminate the possibility it was drilled in more modern times (aka, post copper/bronze age)?

PS: PM sent

 

[sjastro]

I'm also left wondering how these guys established the actual date this core was drilled?

I mean, how did they eliminate the possibility it was drilled in more modern times (aka, post copper/bronze age)?

PS: PM sent

It's likely the core being found at Giza is dated around the period in the early to mid 4th dynasty 4,500 - 4,600 years ago during the pyramid building period in the region.
The site was abandoned around 4,200 years ago in the first recorded revolution and civil war in history (First Intermediate Period of Egypt - Wikipedia) well before bronze tooling became common by the 18th dynasty some 700 years later.

 

[stevevw]

Hello sjastro. I was going to start a thread myself along these lines as it was very interesting.

As I mentioned in the Ripples thread the issue is not the pitch itself that implies advanced tech but the spiralling of the pitch downwards as compared to the horizontal pitch of using a copper pipe and sand as the abrasion.

Each spiralling pitch lands lower on the core than a horizontal pitch thus each rotation dug in deeper than the copper pipe and sand. That was the whole issue at the time when Petrie made his findings and Dunn backed them up. That it was a spiral pitch and not a horizontal one that the copper pipes and sand produced.

Petrie noted that some sort of fixed cutting point must have been used for it to be able to cause a spiral cut and travel down the granite core like a drunken sailor as he described. This is the issue that needs to be addressed.

The other issue is that sand and copper pipe do not cut into the granite and cut through the hardest of conglomerate as easily as the softer as he noted. He proposed something harder than granite like diamond as we use today.

Tests with sand and copper pipe do not cut into the granite like diamond. Its basically abrasing the hole in the granite and thus will be more smooth with light lines on the surface. But certainly not cutting into granite like diamond.

Apart from Petrie and Dunns findings the article below also supports the idea of some sort of fixed cutter harder than granite doing the drilling.

The abrasive used was wet sand. Note that the walls, inner and outer, are rough. There are no lines. A similar finding occurred with crushed quartz.

The abrasive used was corundum in which a finding similar to that of emery is evident.

The abrasive used was diamond. A finding similar to that produced by both emery and corundum is evident.

The findings. They are even suggesting the possiblilty that as Petrie concluded that some sort of fixed diamond cutter caused the spiral cut down the core like a drunken sailor.

Maybe points made from hard minerals like corundum, microcrystalline varieties of quartz or other gemstones could be embedded in another material like copper or wood and used as a graver.
Reading Tool Marks on Egyptian Stone Sculpture - Rivista del Museo Egizio

The other problem is that we have no evidence of any copper pipes being used. We find the small bow drills and we have pics of them being used on the walls. The problem is this comes later.

The granite works such as drill holes up to 14 inches and cuts come from the pre hyroglyphs and painting period in the early dynasties. Possibly even pre dynasty. So this happens when the Egytians and other cultures actually do use bow drills and saws which is later.

Some say this was an attempt to copy works already done and if we look we see the later works and drills holes are inferior copies. Its strange how it seems the works go from high levels of diffulty to less quality works in general. Especially for the Egyptians.

If all these holes were being drilled and we have found the primitive tools that go with the later inferior works with softer stone then we should expect to find copper pipes that went with the earlier works.

 

[stevevw]

I have been trying to contact you, can you send a PM to make sure this is possible?
Here is the ultra advanced technology Chris Dunn has been using to measure the pitch on Petrie's sample.

​

Gizapower - The Petrie Museum 1999 - Chris Dunn VI

You would think he would try using a vernier gauge instead of string, sticky tape and a ruler, even then it is no easy task in lining up the callipers on the grooves to make reproducible measurements.
According to his "measurements" (not sure how many he performed) the Egyptians could produce a pitch in the range of 0.110" - 0.120" whereas on the 52 calculations made by GPT-4o, the range was 0.070" - 0.147".

I think Dunn also too a latext impression of the grooves to determine them as spirals rather than horizontal.

 

[SelfSim]

...
Petrie noted that some sort of fixed cutting point must have been used for it to be able to cause a spiral cut and travel down the granite core like a drunken sailor as he described. This is the issue that needs to be addressed.

No .. it doesn't.
The GPT-4o analysis, taken from the image of original sample, demonstrates the large differences in the resulting core pattern between our modern way of drilling cores and manual methods. The pattern falls well into the category of using imprecise mechanical apparatus/abrasion techniques.

Petrie and Dunn's envisioning what they perceived as being a spiral pattern, is more likely caused by their over-active imaginations, rather than what is evidenced. Their measurement method was sloppy....

Some say this was an attempt to copy works already done and if we look we see the later works and drills holes are inferior copies. Its strange how it seems the works go from high levels of diffulty to less quality works in general. Especially for the Egyptians.

What makes that 'strange'?

I mean, we don't see enormous pyramids being built out of huge stone blocks thesedays, or clocks made from wood, or say the mechancal hand-drills I gew up with as a kid being used in constructions, now do we?
Skills rapidly become archaic (and extinct) whenever the time/effort required to perfect them exceeds the time/effort to achieve similar end results using more modern methods and techniques. This is a consistent phenomenon which accompanies human behaviour throughout history.

Also the Stone Age went for an extremely long time in comparison with the timespan of metallic mechanization. There was plenty of time for Stone Agers to perfect stone-working to the degree we see in megalithic works. (Not to mention the pressures those folk were under to survive nature (and eachother). Those were obviously huge motivators for them to go to the extremes for which they then left evidence behind, demonstrating their struggles against those pressures).

If all these holes were being drilled and we have found the primitive tools that go with the later inferior works with softer stone then we should expect to find copper pipes that went with the earlier works.

Meh .. if copper was useful and valuable, it could've easily been melted down and used for other things ..
Unconvincing argument.

 

[sjastro]

Hello sjastro. I was going to start a thread myself along these lines as it was very interesting.

As I mentioned in the Ripples thread the issue is not the pitch itself that implies advanced tech but the spiralling of the pitch downwards as compared to the horizontal pitch of using a copper pipe and sand as the abrasion.

Each spiralling pitch lands lower on the core than a horizontal pitch thus each rotation dug in deeper than the copper pipe and sand. That was the whole issue at the time when Petrie made his findings and Dunn backed them up. That it was a spiral pitch and not a horizontal one that the copper pipes and sand produced.

Petrie noted that some sort of fixed cutting point must have been used for it to be able to cause a spiral cut and travel down the granite core like a drunken sailor as he described. This is the issue that needs to be addressed.

The other issue is that sand and copper pipe do not cut into the granite and cut through the hardest of conglomerate as easily as the softer as he noted. He proposed something harder than granite like diamond as we use today.

Tests with sand and copper pipe do not cut into the granite like diamond. Its basically abrasing the hole in the granite and thus will be more smooth with light lines on the surface. But certainly not cutting into granite like diamond.

Apart from Petrie and Dunns findings the article below also supports the idea of some sort of fixed cutter harder than granite doing the drilling.

The abrasive used was wet sand. Note that the walls, inner and outer, are rough. There are no lines. A similar finding occurred with crushed quartz.

The abrasive used was corundum in which a finding similar to that of emery is evident.

The abrasive used was diamond. A finding similar to that produced by both emery and corundum is evident.

The findings. They are even suggesting the possiblilty that as Petrie concluded that some sort of fixed diamond cutter caused the spiral cut down the core like a drunken sailor.

Maybe points made from hard minerals like corundum, microcrystalline varieties of quartz or other gemstones could be embedded in another material like copper or wood and used as a graver.
Reading Tool Marks on Egyptian Stone Sculpture - Rivista del Museo Egizio

The other problem is that we have no evidence of any copper pipes being used. We find the small bow drills and we have pics of them being used on the walls. The problem is this comes later.

The granite works such as drill holes up to 14 inches and cuts come from the pre hyroglyphs and painting period in the early dynasties. Possibly even pre dynasty. So this happens when the Egytians and other cultures actually do use bow drills and saws which is later.

Some say this was an attempt to copy works already done and if we look we see the later works and drills holes are inferior copies. Its strange how it seems the works go from high levels of diffulty to less quality works in general. Especially for the Egyptians.

If all these holes were being drilled and we have found the primitive tools that go with the later inferior works with softer stone then we should expect to find copper pipes that went with the earlier works.

You did not provide a link for your images so I decided to find out for myself.

Expedition Magazine | Ancient Egyptian Stone-Drilling

Maybe there was a reason for no link because the images are of silicone rubber impressions of the holes left by drilling holes through granite using copper tubes and abrasives.
The article is not about disproving the use of copper and abrasives and therefore does not support Dunn as you assert.

Given a video was provided in the other thread using the ancient Egyptian methods of copper tube, abrasives and a flywheel operated bow drill which produced similar striation patterns to Petrie’s sample which you implied as being fraudulent, the burden of proof is on you to show this.

In the meantime, this thread shows when complete pitch data is revealed of Petrie’s sample and analysed, it is not indicative the Egyptians possessed some advanced technology beyond our own as proposed by Dunn.

 

[SelfSim]

You did not provide a link for your images so I decided to find out for myself.

Expedition Magazine | Ancient Egyptian Stone-Drilling

Maybe there was a reason for no link because the images are of silicone rubber impressions of the holes left by drilling holes through granite using copper tubes and abrasives.
The article is not about disproving the use of copper and abrasives and therefore does not support Dunn as you assert.

Given a video was provided in the other thread using the ancient Egyptian methods of copper tube, abrasives and a flywheel operated bow drill which produced similar striation patterns to Petrie’s sample which you implied as being fraudulent, the burden of proof is on you to show this.

In the meantime, this thread shows when complete pitch data is revealed of Petrie’s sample and analysed, it is not indicative the Egyptians possessed some advanced technology beyond our own as proposed by Dunn.

No mention of spirals in the Expedition Magazine article either.

The missing 'advanced technology' seems to be the lubricant (olive oil to the rescue) .. and not the type of the metal used for the tube.

Interesting!

 

[sjastro]

No mention of spirals in the Expedition Magazine article either.

The missing 'advanced technology' seems to be the lubricant (olive oil to the rescue) .. and not the type of the metal used for the tube.

Interesting!

The article is rather old from 1983 when the use of corundum was only a hypothesis, since then the abrasive including fragments of copper tube have been found in a partially drilled hole in limestone.

Hidden Secrets of Ancient Egyptian Technology - The Metropolitan Museum of Art

Conservator Anna Serotta and Associate Research Scientist Federico Carò explore a small stone fragment from the Museum's collection that may hold key information about the use of high-performance abrasives in ancient Egypt.

www.metmuseum.org

 

[SelfSim]

The article is rather old from 1983 when the use of corundum was only a hypothesis, since then the abrasive including fragments of copper tube have been found in a partially drilled hole in limestone.

Hidden Secrets of Ancient Egyptian Technology - The Metropolitan Museum of Art

Conservator Anna Serotta and Associate Research Scientist Federico Carò explore a small stone fragment from the Museum's collection that may hold key information about the use of high-performance abrasives in ancient Egypt.

www.metmuseum.org

Yes .. interesting.
I guess this sample would likely date from during the construction phase of the Great Temple of the Aten at Amarna, (Egypt), which would have been prior to the period of about 18th Dynasty 1353–1336 BCE (according to Wiki)?

 

[stevevw]

You did not provide a link for your images so I decided to find out for myself.

Expedition Magazine | Ancient Egyptian Stone-Drilling

Sorry the link I provided at the end was suppose to be of the drill core tests. Not sure how that happened. The link you found is the correct one.

Maybe there was a reason for no link because the images are of silicone rubber impressions of the holes left by drilling holes through granite using copper tubes and abrasives.
The article is not about disproving the use of copper and abrasives and therefore does not support Dunn as you assert.

I never said the article was about disproving or proving anything. It even qualifies this by making a suggestion rather than a definite finding. It suggests that a fixed point diamond type cutter may best fit the signature in the core rather than saying this is definitely how it was created.

Thats the whole point. To lay out the findings so we can make some conclusions as to what the evidence is pointing to.

Given a video was provided in the other thread using the ancient Egyptian methods of copper tube, abrasives and a flywheel operated bow drill which produced similar striation patterns to Petrie’s sample which you implied as being fraudulent, the burden of proof is on you to show this.

If your talking about the video from Stokes then yest this was found to be a misrepresentation of the findings. The core from that experiement was later sent for analysis by Brownles and Reid where they took a photo of the core and examined it rather than examining the core in real time.

The photograph in Lawton/Herold’s book shows the Valley Core in black and white and it is tilted on an angle. The grooves cut into the diameter of the cone have the appearance of being horizontal, which would give a casual observer the impression that they were not spiral.

Petrie’s Infamous Core #7 – Giza Power

gizapower.com

Here is another idea as to how the drill cores were produced. In this case some sort of chemical reaction which made it easier to cut into the granite. The important point here is that just a copper pipe with sand abrasion did not create the drill holes as it was inadequate but some chemical aid was needed.

So perhaps the truth lies elsewhere and we need to do more tests. But to claim it was absolutely caused by a copper pipe and sand abrasion is unjustified at this stage.

https://vixra.org/pdf/1503.0182v1.pdf

In the meantime, this thread shows when complete pitch data is revealed of Petrie’s sample and analysed, it is not indicative the Egyptians possessed some advanced technology beyond our own as proposed by Dunn.

Ok we this is what we are endeavouring to find out for sure. I don't think that will be completely possible as still the experts are in disagreement. That is why the spiral cuts that at the very least continue for some 3 feet in places is so important. Because if they are spiral and continious even for 2 or 3 feet then this is completely different to the horizontal lighter lines caused by a copper pipe and sand abrasion.

Another problem as mentioned earlier is that as someone from your side claimed if we don't find any advanced tech tools to account for the signatures in the stone then there is no evidence for advanced tech.

The same logic should apply to the claimed primitive tech. We don't find any large copper pipes that can explain the drill holes.

We have drill holes in corners where a bow drill will be restricted. We have up to 14 inch drill holes and some overlapping and some that show clear and sharp and precise cuts on edges of granite. Something a bullish abrasion could not achieve as its abrasing and not cutting.

These all need to be accounted for and not assumed to be made by the claimed copper pipe and sand abrasion. The drill cores also should not be taken in isolation but are part of a number of unexplained signatures in the rocks. Altogether these are making a case for something beyond the primitive tools claimed to be used. This also needs to be explained.

 

[sjastro]

Sorry the link I provided at the end was suppose to be of the drill core tests. Not sure how that happened. The link you found is the correct one.

I never said the article was about disproving or proving anything. It even qualifies this by making a suggestion rather than a definite finding. It suggests that a fixed point diamond type cutter may best fit the signature in the core rather than saying this is definitely how it was created.

Thats the whole point. To lay out the findings so we can make some conclusions as to what the evidence is pointing to.

The is this one of your typical about faces which is frankly getting rather tiresome.

If your talking about the video from Stokes then yest this was found to be a misrepresentation of the findings. The core from that experiement was later sent for analysis by Brownles and Reid where they took a photo of the core and examined it rather than examining the core in real time.

The photograph in Lawton/Herold’s book shows the Valley Core in black and white and it is tilted on an angle. The grooves cut into the diameter of the cone have the appearance of being horizontal, which would give a casual observer the impression that they were not spiral.

Petrie’s Infamous Core #7 – Giza Power

gizapower.com

Why don’t you try reading and comprehending what I stated for once, the issue is about the video I posted and the close up comparisons with Petrie’s sample which you implied are fraudulent.

Here is another idea as to how the drill cores were produced. In this case some sort of chemical reaction which made it easier to cut into the granite. The important point here is that just a copper pipe with sand abrasion did not create the drill holes as it was inadequate but some chemical aid was needed.

So perhaps the truth lies elsewhere and we need to do more tests. But to claim it was absolutely caused by a copper pipe and sand abrasion is unjustified at this stage.

https://vixra.org/pdf/1503.0182v1.pdf

Do you realize this link bags Dunn’s hypothesis and is yet another example of your contradiction of championing Dunn while coming up with a link which opposes it?
This one is equally nonsensical as pure solid hydroxides namely NaOH and KOH needed to make concentrated alkali solutions require technologies which the Egyptians did not possess.
There is also no evidence of any form of chemical etching in Petrie’s core no.7 sample only striations produced by mechanical action.

Ok we this is what we are endeavouring to find out for sure. I don't think that will be completely possible as still the experts are in disagreement. That is why the spiral cuts that at the very least continue for some 3 feet in places is so important. Because if they are spiral and continious even for 2 or 3 feet then this is completely different to the horizontal lighter lines caused by a copper pipe and sand abrasion.

Another problem as mentioned earlier is that as someone from your side claimed if we don't find any advanced tech tools to account for the signatures in the stone then there is no evidence for advanced tech.

The same logic should apply to the claimed primitive tech. We don't find any large copper pipes that can explain the drill holes.

We have drill holes in corners where a bow drill will be restricted. We have up to 14 inch drill holes and some overlapping and some that show clear and sharp and precise cuts on edges of granite. Something a bullish abrasion could not achieve as its abrasing and not cutting.

These all need to be accounted for and not assumed to be made by the claimed copper pipe and sand abrasion. The drill cores also should not be taken in isolation but are part of a number of unexplained signatures in the rocks. Altogether these are making a case for something beyond the primitive tools claimed to be used. This also needs to be explained.

You are in complete denial mode, having been shown videos of people cutting through granite using copper saws and abrasive, drilling holes through granite using copper tube and abrasives producing similar patterns to Petrie’s sample. There was even evidence of copper tube and abrasives in partially drilled limestone which you ridiculously hand waved away by suggesting the Egyptians used primitive technologies on softer stone and advanced technologies way beyond current levels for granite.

 

[sjastro]

I decided to test GPT-4o's Python code on a threaded bolt which for a 10mm diameter and coarse thread has an average pitch of 1.5mm ± 0.034mm.

​

By comparison using astronomical software on the thread.

​

GPT-4o is having problems accurately identifying the pixel positions of the crests on the thread but for the point of the original post is far more accurate than Dunn's method of using sticky tape, a string and ruler in measuring the pitch on Petrie's sample.

This might be AI project to improve GPT-4o's measuring capabilities.

 

[sjastro]

The pitch analysis done by astronomical software and GPT-4o on the Petrie sample are compatible although the software could only sample a select region where there was little on no damage to the groove structure, GPT-4o enhanced the image and did full analysis.
Both show Dunn's measurements and technique are woefully inadequate.

Astronomical software on 29 turns.

GPT-4o on 52 turns

 

[SelfSim]

The pitch analysis done by astronomical software and GPT-4o on the Petrie sample are compatible although the software could only sample a select region where there was little on no damage to the groove structure, GPT-4o enhanced the image and did full analysis.
Both show Dunn's measurements and technique are woefully inadequate.

Astronomical software on 29 turns.

View attachment 357912

GPT-4o on 52 turns

View attachment 357908​

So, if I'm reading this right, the Dunn average pitch of 0.1 inches was close to GPT's 0.095 inches, but the GPT (astro) measured variance of +/-25% between turns, implies a highly unpredictable/irregular descent rate of the drill bit(?)

Speculating that the so-called 'advanced technology' speculatively used, (in the worst case), may have had some kind of modern screw-like coarse thread as the mechanism controlling the descent thru the granite, should produce (sort of) only about +/-5.4% variance in the pitch of the core sample(?)

GPT's error using astro image analysis is only about +/- 0.023%, so its fair to say GPT's astro measurements don't introduce the almost 5x greater variance. Thus its fair to conclude that the big pitch variance is likely attributable to the manual component of method used in original core sample(?)

 

[sjastro]

So, if I'm reading this right, the Dunn average pitch of 0.1 inches was close to GPT's 0.095 inches, but the GPT (astro) measured variance of +/-25% between turns, implies a highly unpredictable/irregular descent rate of the drill bit(?)

Speculating that the so-called 'advanced technology' speculatively used, (in the worst case), may have had some kind of modern screw-like coarse thread as the mechanism controlling the descent thru the granite, should produce (sort of) only about +/-5.4% variance in the pitch of the core sample(?)

GPT's error using astro image analysis is only about +/- 0.023%, so its fair to say GPT's astro measurements don't introduce the almost 5x greater variance. Thus its fair to conclude that the big pitch variance is likely attributable to the manual component of method used in original core sample(?)

Here is a summary.

Measurement​	Mean Pitch​	Standard Deviation​
GPT-4o​	0.095" (52 measurements)​	± 24.66%​
Astro Software (PixInsight)​	0.098" (29 measurements)​	± 24.57%​
Dunn​	0.1" (Unknown number of pitch measurements)​	For a diamond tip tool operating at 1,000 RPM the pitch tolerance for the diameter of Petrie's sample would typically be around ± 3.0%.

What ever process went into drilling out Petrie's sample, the high standard deviations as measured by both GPT-4o and PixInsight is simply not capable to meet industry standards.
The simplest and most logical explanation is the drilling out of the granite core was done by traditional Egyptian methods as confirmed by archaeological evidence and not some super technology well beyond the feed rates of modern drilling equipment.

Dunn has assumed a nearly constant pitch as was the RPM meaning the feed rate of 0.1"/turn is way beyond anything modern equipment can achieve (around 0.0002"/turn).
The problem is when pitch and RPM are not constant as is reflected in the Egyptian process, the mean pitch is not an indicator of a high feed rate.

In Dunn's case where F is the feed rate, P the pitch and ω the angular velocity.

In the Egyptian method P and ω are functions of time t.

Hence the pitch values measured by GPT-4o and PixInsight vary and are not indicative of a high feed rate.