Stonehenge secret: Did builders use Pythagoras' theorem 2,000 years before the philosopher lived?

The famous ancient site at Stonehenge may have been built using Greek philosopher Pythagoras’ famous theorem two millennia before the mathematical equation was developed, experts say.

A new book titled “Megalith: Studies in Stone,” argues that the same geometric principles that framed Pythagoras’ famous work can be found at the prehistoric site. The book’s publication coincides with the Thursday’s summer solstice, which is closely associated with Stonehenge.

The World Heritage site is known for its alignment with the movements of the Sun - thousands travel to the site in Avebury, Southern England, to mark the solstices in Summer and Winter.

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The first monument at the site, an early “henge” monument, was constructed about 5,000 years ago. The world-famous stone circle was built around 2,500 B.C. during the late Neolithic period. 

The sun rises through the stones at Stonehenge as crowds of people gather to celebrate the dawn of the longest day in the UK, in Wiltshire, England, Thursday June 21, 2018. The neolithic Wiltshire monument is built along the solstice alignment of the summer sunrise and the winter sunset. (Ben Birchall/PA via AP)

The sun rises through the stones at Stonehenge as crowds of people gather to celebrate the dawn of the longest day in the UK, in Wiltshire, England, Thursday June 21, 2018. The neolithic Wiltshire monument is built along the solstice alignment of the summer sunrise and the winter sunset. (Ben Birchall/PA via AP)

Citing the book’s authors, The Telegraph reports that a rectangle of four Sarsen stones, or sandstone blocks, when split in half diagonally, forms a perfect Pythagorean 5:12:13 triangle. The Sarsen stones date to 2,750 B.C.

One of the book’s contributors, Robin Heath, also proposes the existence of a great Pythagorean triangle in the English landscape link Stonehenge, the site in Wales from which its bluestones were cut, and Lundy Island, a prehistoric site in England’s Bristol Channel.

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Greek philosopher Pythagoras is credited with discovering the famous geometric theorem stating that, in a right-angled triangle “the square of the hypotenuse is equal to the sum of the squares of the other two sides,” often written as a^2 + b^2 = c^2. Pythagoras is believed to have lived in the 6th and 5th centuries B.C.

In addition to the Stonehenge researchers, other experts say that they have found evidence of the famous theorem long before the time of Pythagoras. Last year, for example, scientists revealed the secrets of a mysterious 3,700-year-old Babylonian clay tablet, which they describe as the world’s oldest and most accurate trigonometric table.

The tablet, known as Plimpton 322, was discovered in the early 1900s in what is now Southern Iraq by archaeologist, academic, diplomat and antiquities dealer Edgar Banks, who provided the inspiration for the fictional character ‘Indiana Jones.’

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Thousands watched the sun glint over the horizon at Stonehenge on Thursday. The sun rose behind the Heel Stone, which traditionally marks the spot on the horizon for the sunrise. Crowds cheered and raised mobile phones for images as the rays flooded through the monument and announced the longest day of the year in the Northern Hemisphere.

The Associated Press contributed to this article.

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