Four-thousand years ago, an urban civilization lived and traded on what is now the border between Pakistan and India. During the past century, thousands of artifacts bearing hieroglyphics left by this prehistoric people have been discovered. Today, a team of Indian and American researchers are using mathematics and computer science to try to piece together information about the still-unknown script.
The team led by a University of Washington researcher has used computers to extract patterns in ancient Indus symbols. The study, published this week in the Proceedings of the National Academy of Sciences, shows distinct patterns in the symbols’ placement in sequences and creates a statistical model for the unknown language.
“The statistical model provides insights into the underlying grammatical structure of the Indus script,” said lead author Rajesh Rao, a UW associate professor of computer science. “Such a model can be valuable for decipherment, because any meaning ascribed to a symbol must make sense in the context of other symbols that precede or follow it.” …
“The finding that the Indus script may have been versatile enough to represent different subject matter in West Asia is provocative. This finding is hard to reconcile with the claim that the script merely represents religious or political symbols,” Rao said.
The researchers used a Markov model, a statistical method that estimates the likelihood of a future event (such as inscribing a particular symbol) based on patterns seen in the past. The method was first developed by Russian mathematician Andrey Markov a century ago and is increasingly used in economics, genetics, speech-recognition and other fields.
“One of the main purposes of our paper is to introduce Markov models, and statistical models in general, as computational tools for investigating ancient scripts,” Adhikari said.
One application described in the paper uses the statistical model to fill in missing symbols on damaged archaeological artifacts. Such filled-in texts can increase the pool of data available for deciphering the writings of ancient civilizations, Rao said.