A French team surveying the Great Pyramid in the 1980s revealed a spiral shape pattern they did not understand. The team were using a technique called microgravimetry, used to measure the density of buildings in order to find hidden chambers. Not until Jean-Pierre Houdin met with the archaeologists did they understand this spiral was likely to be an internal ramp. This is the best evidence anybody has come up with so far to prove any theory about the Pyramids at Giza.  Further exploration of the Pyramids confirmed another elements of Houdin’s theory. A notch visible from the outside, 270 feet up, may have been one of the notches used in the construction. According to Houdin, the pyramid would have needed notches on the corners for the internal ramp to work, these would have been the last part of the pyramid built, and would have been filled in at the end. The notch is set into one of the corners and would have had a crane attached to turn blocks across the 90-degree angle. The notch has an L-shaped room behind it, which may have been the intersection of two parts of the ramp. This room would have allowed the workers to fill in the corners at the end of the pyramid’s construction. The four edges of the pyramid were the lowest density part of the building the 1980s survey. Finally, in 2017, a hundred-foot-long void was detected in the Great Pyramid using muon radiography. The chamber is very similar in its dimensions to the Great Gallery beneath it and is conveniently placed in such a way that it would have been ideal to move blocks into place over the King’s Chamber.  Recent surveys using different archaeological and scientific techniques have confirmed there are spaces inside the pyramid which may be the remains of an internal ramp.
Some of the investigations that have proved Houdin’s theory have come from companies attached to him personally. It is possible he is interpreting facts to suit his own conclusions and more scans and surveys need to be done. So far muon radiography has only confirmed the existence of one void in the pyramid. Without opening the pyramid it is impossible to confirm what it was used for. Houdin's theory is not yet confirmed. Some of the investigations done may have been biased.
[P1] A series of surveys of the Great Pyramid appear to confirm Houdin's internal ramp does exist [P2] No other theory has anything like this much evidence [C] An internal ramp was used to build the Pyramids
Rejecting the premises