From the Scientific American , via 3QuarksDaily , an article on “how to count to a zillion without falling off the end of the number line”:
Last year the National Debt Clock in New York City ran out of digits. The billboard-size electronic counter, mounted on a wall near Times Square, overflowed when the public debt reached $10 trillion, or 10 13 dollars. The crisis was resolved by squeezing another digit into the space occupied by the dollar sign. Now a new clock is on order, with room for growth; it wont fill up until the debt reaches a quadrillion (10 15 ) dollars.
The incident of the Debt Clock brings to mind a comment made by Richard Feynman in the 1980sback when mere billions still had the power to impress:
There are 10 11 stars in the galaxy. That used to be a huge number. But its only a hundred billion. Its less than the national deficit! We used to call them astronomical numbers. Now we should call them economical numbers.
The important point here is not that high finance is catching up with the sciences; its that the numbers we encounter everywhere in daily life are growing steadily larger. Computer technology is another area of rapid numeric inflation. Data storage capacity has gone from kilobytes to megabytes to gigabytes, and the latest disk drives hold a terabyte (10 12 bytes). In the world of supercomputers, the current state of the art is called petascale computing (10 15 operations per second), and there is talk of a coming transition to exascale (10 18 ). After that, we can await the arrival of zettascale (10 21 ) and yottascale (10 24 ) machinesand then we run out of prefixes!