Heisenbug

Common card · No. 203381

In computer programming jargon, a heisenbug is a software bug that seems to disappear or alter its behavior when one attempts to study it. The term is a pun on the name of Werner Heisenberg, the physicist who first introduced the uncertainty principle, and it is a reference to the observer effect, which states that the act of observing a system inevitably alters its state. In electronics, the traditional term is probe effect, where attaching a test probe to a device changes its behavior. The term has been criticized because it confuses Heisenberg's uncertainty principle (to which it owes the name) with the observer effect in quantum mechanics, which are distinct concepts. Similar terms, such as "bohrbug", "mandelbug", "hindenbug", and "schrödinbug" (see the section on related terms) have been occasionally proposed for other kinds of unusual software bugs, sometimes in jest.

Read on Wikipedia