- The halting problem is “undecidable”: there’s no algorithm which can tell you if an arbitrary program with an arbitrary input will halt or not. IE, if you give me a proposed “halt-detector”, I can inspect it and come up with a program and input for which it would give the wrong answer.
- Granite (Wikipedia)
Granite (/ˈɡrænɪt/ GRAN-it) is a coarse-grained (phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies underground. It is common in the continental crust of Earth, where it is found in igneous intrusions. These range in size from dikes only a few centimeters across to batholiths exposed over hundreds of square kilometers.