Part of the Casswiki article series Cassiopaean Experiment
In general usage, this term means the ratio between useful information and random information which is independent of the main information and does not contribute to it but can still be confused with it. In electronics, this refers to the ratio of the magnitude of a known reference signal and all other signals measured in an experiment. See electronics texts for more detail.
As used by the FOTCM, the term means the ratio between information relevant to a conversation and information which seeks to detract from the topic. An exact definition is not possible since what is or is not relevant is not always clear.
Noise in the above sense can be of various qualities: It can be deliberate obfuscation seeking to confuse the issue, often by introducing counter arguments out of context. It can be simple idle chatter. It can be constantly repeating the same points. Techniques of disrupting any conversation are too numerous to list here. See articles on the Internet discussing professional debunkery for more examples.