One of the most remarkable ideas in this theoretical framework is that the definite properties of objects that we associate with classical physics—position and speed, say—are selected from a menu of quantum possibilities in a process loosely analogous to natural selection in evolution: The properties that survive are in some sense the “fittest.” As in natural selection, the survivors are those that make the most copies of themselves.
In our case, to randomly output a 50-bit string, you can build a quantum circuit that puts 50 qubits, taken together, into a superposition of states that captures the distribution you’d like to re-create.
By way of Galileo’s simple observation so length and time were seen to be linked—a linkage that made it possible that a length could be derived not simply from the dimensions of limbs and knuckles and strides, but by the hitherto quite unanticipated observation of the passage of time.From the book The Perfectionists: How Precision Engineers Created the Modern World by Simon Winchester.HarperA century later an English divine, John Wilkins, proposed employing Galileo’s discovery to create an entirely new fundamental unit, one that had nothing to do with the then-traditional standard in England, which was a rod that was more or less officially declared to be the length of a yard.
Once it settles into orbit 310 miles above the Earth, the satellite will start collecting data using a specially designed laser device that will give scientists more data about exactly where ice is melting and how fast.The NASA satellite will scan the Earth’s surface using six green laser beams to measure glaciers and floating sea ice.
NASA’s Ice, Cloud and land Elevation Satellite-2 (ICESat-2) will provide scientists with height measurements that create a global portrait of Earth's third dimension, gathering data that can precisely track changes of terrain including glaciers, sea ice, and forests.