# Lambda Nature

Lambda is a greek letter (looks something like an up-side-down back-to-front y) that is often used to represent these things:
• An EigenValue of a matrix
• The decay constant of a radioactive material (not the half-life), or other exponential process
• FunctionalAbstraction? in the LambdaCalculus and, usually spelled out, some programming languages (typically FunctionalProgrammingLanguages, but not always) related to that calculus
• In the context of 'lambda sensor', an exhaust oxygen sensor in a closed-loop fuel management system for an internal combustion engine
• Wavelength

These are represented by lower case lambda (&#955; or &lambda;).

By talking about the lambda nature of a programming language, we usually mean the tendency of treating functions as values (instead of special constructs) and functions having LexicalClosures.

There is also a capital Lambda (&#923; or &Lambda;) -- not sure what that is used for, outside of fraternity house names.

• The cosmological constant
• TypeAbstraction? in SystemF

(note: I just tried to type lambdas in Unicode, but somehow they got converted to numeric entity names, which were already there, so I removed them. I'm using Mozilla 1.5.)

try change \frac to \lambda at http://www.equationsheet.com/entertex.php?SID=XXXXXBOT

Does a dog have lambda nature? MuAnswer.

No no, mu is the next Greek letter!-)