The Social Security System
The viability of the pay-as-you-go system is threatened by economic and demographic trends. The retired population and its benefits are growing faster than the active work force and its tax contributions...
The viability of the pay-as-you-go system is threatened by economic and demographic trends. The retired population and its benefits are growing faster than the active work force and its tax contributions...
Many species of plants and animals, notably the dinosaurs, suddenly died out about 63 million years ago. A thin stratum of iridium-rich material suggests the cause may have been the fall of an asteroid...
The gas combines explosively in familiar environments to form molecular hydrogen. A new technique that inhibits the reaction makes it possible to study certain properties of a quantum gas...
The 17 icy bodies that orbit the planet display a surprising range of geological evolution. Many of them show craters more than four billion years old, but one of them has terrain so new that no craters are seen...
The Cray-1 and the CYBER 205 can perform 100 million arithmetic operations per second. This kind of "number crunching" is needed for the solution of complex problems such as those in fluid dynamics...
Tracing the pedigree of nerve cells in the embryonic growth of dwarf and giant leeches yields preliminary clues to the functioning of the adult nervous system
A legacy of Alexander's conquest of Persia was a Greek kingdom in what is now Afghanistan. A French archaeological group has spent the past 15 years unearthing one of its cities, Ai Khanum...
When people make risky choices, they often do not do so objectively. Experimental surveys indicate that such departures from objectivity tend to follow regular patterns that can be described mathematically...