"* Curl is a word coined by Hamilton to denote the fluid rotation over a surface area.*" [Carol White, Energy Potential - Toward a New Electromagnetic Field Theory, page 115]

In vector calculus, the **curl** (or rotor) is a vector operator that describes the infinitesimal rotation of a 3-dimensional vector field. At every point in the field, the **curl** is represented by a vector. The attributes of this vector (length and direction) characterize the rotation at that point.

The direction of the **curl** is the axis of rotation, as determined by the right-hand rule, and the magnitude of the **curl** is the magnitude of rotation. If the vector field represents the flow velocity of a moving fluid, then the **curl** is the circulation density of the fluid. A vector field whose **curl** is zero is called irrotational. The **curl** is a form of differentiation for vector fields. The corresponding form of the fundamental theorem of calculus is Stokes' theorem, which relates the surface integral of the **curl** of a vector field to the line integral of the vector field around the boundary curve.

The alternative terminology rotor or rotational and alternative notations rot F and âˆ‡Ã—F are often used (the former especially in many European countries, the latter using the del operator and the cross product) for **curl** and **curl** F.

Unlike the gradient and divergence, **curl** does not generalize as simply to other dimensions; some generalizations are possible, but only in three dimensions is the geometrically defined **curl** of a vector field again a vector field. This is a similar phenomenon as in the 3 dimensional cross product, and the connection is reflected in the notation âˆ‡Ã— for the **curl**.

The name "**curl**" was first suggested by James Clerk Maxwell in 1871. wikipedia

See **Rayleigh Wave**

See Also

**Bearden on Tesla and EM Source Charge**
**Berry Phase**
**coupling**
**Eighteen Attributes or Dimensions**
**Figure 13.05a - Complex Vortex Rotational Dynamics**
**Heaviside Component**
**Rayleigh Wave**
**Revolution**
**Rotation**
**Rotational-vibrational coupling**
**Rovibrational coupling**
**Scalar**
**Scalar electromagnetics**
**Stria**
**Sympathetic Negative Interference** energy moves in circles (vortex)
**Vibronic coupling**
**9.30 - Eighteen Attributes of a Wave**
**12.11 - Eighteen Attributes or Dimensions**