Search results
Results from the WOW.Com Content Network
Magnetic helicity is a gauge-dependent quantity, because can be redefined by adding a gradient to it (gauge choosing).However, for perfectly conducting boundaries or periodic systems without a net magnetic flux, the magnetic helicity contained in the whole domain is gauge invariant, [15] that is, independent of the gauge choice.
Helicity (particle physics), the projection of the spin onto the direction of momentum Magnetic helicity , the extent to which a magnetic field "wraps around itself" Circular dichroism , the differential absorption of left and right circularly polarized light
Lorentz TEM image of helical spin stripes in iron germanide (FeGe) at 90 K. Helimagnetism is a form of magnetic ordering where spins of neighbouring magnetic moments arrange themselves in a spiral or helical pattern, with a characteristic turn angle of somewhere between 0 and 180 degrees.
Helicity plays a central role in dynamo theory, the theory of spontaneous generation of magnetic fields in stars and planets (Moffatt 1978, Parker 1979, Krause & Rädler 1980). It is known that, with few exceptions, any statistically homogeneous turbulent flow having nonzero mean helicity in a sufficiently large expanse of conducting fluid will ...
In plasma physics, Woltjer's theorem states that force-free magnetic fields in a closed system with constant force-free parameter represent the state with lowest magnetic energy in the system and that the magnetic helicity is invariant under this condition.
The helicity of a particle is positive (" right-handed") if the direction of its spin is the same as the direction of its motion and negative ("left-handed") if opposite. Helicity is conserved. [1] That is, the helicity commutes with the Hamiltonian, and thus, in the absence of external forces, is time-invariant. It is also rotationally ...
Magnetic charge is a pseudoscalar as it is mathematically defined, regardless of whether it exists physically. Magnetic flux is the result of a dot product between a vector (the surface normal) and pseudovector (the magnetic field). Helicity is the projection (dot product) of a spin pseudovector onto the direction of momentum (a true vector).
In a dynomak, magnetic induction is used to create a plasma current inside a plasma filled chamber. This gets the plasma moving and the system eventually relaxes into a Taylor state or spheromak. The relaxation process involves the flow of magnetic helicity (a twist in the field lines) from the injectors into the center of the machine. [19]