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Ancient Tablet Reveals Babylonians Discovered Trigonometry (sciencemag.org)
An anonymous reader quotes a report from Science Magazine: Trigonometry, the study of the lengths and angles of triangles, sends most modern high schoolers scurrying to their cellphones to look up angles, sines, and cosines. Now, a fresh look at a 3700-year-old clay tablet suggests that Babylonian mathematicians not only developed the first trig table, beating the Greeks to the punch by more than 1000 years, but that they also figured out an entirely new way to look at the subject. However, other experts on the clay tablet, known as Plimpton 322 (P322), say the new work is speculative at best. Consisting of four columns and 15 rows of numbers inscribed in cuneiform, the famous P322 tablet was discovered in the early 1900s in what is now southern Iraq by archaeologist, antiquities dealer, and diplomat Edgar Banks, the inspiration for the fictional character Indiana Jones.
Now stored at Columbia University, the tablet first garnered attention in the 1940s, when historians recognized that its cuneiform inscriptions contain a series of numbers echoing the Pythagorean theorem, which explains the relationship of the lengths of the sides of a right triangle. (The theorem: The square of the hypotenuse equals the sum of the square of the other two sides.) But why ancient scribes generated and sorted these numbers in the first place has been debated for decades. Mathematician Daniel Mansfield of the University of New South Wales (UNSW) realized that the information he needed was in missing pieces of P322 that had been reconstructed by other researchers. He and UNSW mathematician Norman Wildberger concluded that the Babylonians expressed trigonometry in terms of exact ratios of the lengths of the sides of right triangles, rather than by angles, using their base 60 form of mathematics, they report today in Historia Mathematica.
Now stored at Columbia University, the tablet first garnered attention in the 1940s, when historians recognized that its cuneiform inscriptions contain a series of numbers echoing the Pythagorean theorem, which explains the relationship of the lengths of the sides of a right triangle. (The theorem: The square of the hypotenuse equals the sum of the square of the other two sides.) But why ancient scribes generated and sorted these numbers in the first place has been debated for decades. Mathematician Daniel Mansfield of the University of New South Wales (UNSW) realized that the information he needed was in missing pieces of P322 that had been reconstructed by other researchers. He and UNSW mathematician Norman Wildberger concluded that the Babylonians expressed trigonometry in terms of exact ratios of the lengths of the sides of right triangles, rather than by angles, using their base 60 form of mathematics, they report today in Historia Mathematica.
The Babylonians didn't invent trigonometry, they invented time travel. They went into the future and stole trigonometry from us.
There's a lot to be said, but Slashdot has been infested with such hilarious Redditors. I never thought I'd miss the days when Digg commenters infested slashdot. Says something when the likes of Digg is far preferred to the likes of Reddit.
moving on...
the famous P322 tablet was discovered in the early 1900s in what is now southern Iraq by archaeologist, antiquities dealer, and diplomat Edgar Banks
From Plimpton 322 wiki,
So my comment isn't earth shattering, but at least you're smarter than you were a moment ago, unlike after reading any of the comments above mine. Go home Redditors, you're drunk.
The tablet doesn't really contain trigonometry as we understand it today. There is no concept of angle, for instance.
That's absolutely true and also why the discovery is so interesting. It is trigonometry. Trigonometry without angles. The authors have a YouTube video which is very informative Here. There are so many interesting things about this. Angles are not needed to work with triangles. The sexagesimal numbering system had many advantages over our current decimal system from an application perspective. It's just a whole new way of thinking about trig. Anyway, it's well worth 20 minutes of your time.
That is what it does do. However, it requires that you have a ladder an integer number of units high, and place the bottom an integer number of units from the wall, and those integers must be in a predetermined ratio.
Basically, it is a list of triangles like 3,4,5 and 13,12,5 but, because they used base 60, there are a lot more of them in a given range.
However, the strategy for finding the answers in the table, and the way in which the table is laid out, are way more useful to builders and surveyors than the tables we used prior to calculators being invented, and the answers (for the values in the table) are more accurate than many tables generated before the use of computers, as the method relied entirely on manipulating integers, rather than 4 figure log tables generating decimals to a fixed number of figures by expounding a power series to a limited number of terms.
I was skeptical at first, but I am inclined to agree that it actually IS a different trigonometry, and it gives useful and practical results - but it does so by not solving the general case. However, it covers most cases that would be encountered by people using the technology of the day. (eg pyramid builders, land surveyors, and very probably boat builders). It is likely woefully inadequate for celestial navigation, but I have not tried it ;-)
Sent from my ASR33 using ASCII
Enmerkar is building a tower/temple to the goddess Inana at Eridu. He asks her for permission to collect a tribute from Aratta. The messenger is told to threaten to destroy Aratta and disperse the people if they don't pay up, and to chant a song asking Enki to fix the languages - "change the speech in their mouths, as many as he had placed there".
Sumerian translations aren't perfect, so we aren't positive if Enki is to fix the languages that he had broken earlier, or break the single language now.
Oh, and towards the end, writing gets invented. The messages back and forth get longer and longer until the poor messenger can't remember it all - "The messenger, whose mouth was heavy, was not able to repeat it." - so the king invents writing, which makes the messenger positively giddy. That is in lines 500-514.
See that "Preview" button?