Plasma (physics) potential in the space between charged particles, independent of how it can be measured, is called the "plasma potential", or the "space potential". If an electrode is inserted into a plasma, its potential will generally lie considerably below the plasma potential due to what is termed a Debye sheath. The good electrical conductivity of plasmas makes their electric fields very small. This results in the important concept of "quasineutrality", which says the density of negative charges is approximately equal to the density of positive charges over large volumes of the plasma (formula_6), but on the scale of the Debye length
Positive liberty Berlin described a statement such as "I am slave to no man" as one of negative liberty, that is, freedom from another individual's direct interference. He contrasted this with a Positive Freedom statement such as "I am my own master", which lays claim to a freedom to choose one's own pursuits in life. Charles Taylor sees Negative Freedom as an "opportunity-concept": one possesses Negative Freedom if one is not enslaved by external forces, and has equal access to a society's resources (regardless of how one decides to spend their time). Positive Freedom, says Taylor, is an "exercise-concept": possessing it might