Field (physics)From Wikipedia, the free encyclopediaThe magnitude and direction of a two-dimensional electric field surrounding two equally charged (repelling) particles. Brightness represents magnitude and hue represents direction.Oppositely charged (attracting) particles.Afieldis aphysical quantitythat has a value for each point inspaceandtime.[1]For example, in a weather forecast, the wind velocity during a day over a country is described by assigning a vector to each point in space. Each vector represents the direction of the movement of air at that point. As the day progresses, the directions in which the vectors point change as the directions of the wind change.A field can be classified as ascalar field, avector field, aspinor field, or atensor fieldaccording to whether the value of the field at each point is ascalar, avector, aspinor(e.g., a Dirac electron) or, more generally, atensor, respectively. For example, theNewtoniangravitational fieldis a vector field: specifying its value at a point in spacetime requires three numbers, the components of the gravitational field vector at that point. Moreover, within each category (scalar, vector, tensor), a field can be either aclassical fieldor aquantum field, depending on whether it is characterized by numbers orquantum operatorsrespectively.A field may be thought of as extending throughout the whole of space. In practice, the strength of every known field has be