By spinning the sample around a given axis, their average angular dependence becomes:
If one sets , then the average angular dependence goes to zero.
The "2", the "P", and the "x,y,z" actually stand for the radial and angular dependence of the solutions.
The importance of the effect is that it provides information on the angular dependence of the intermolecular potential.
Hence, the angular dependence is replaced by a dependence on position in the experimental approach.
In addition that have argued that spin sources will interact via a new inverse square law force with a very unusual angular dependence.
In addition to the angular dependence described above, the response of a directional microphone depends on the amplitude, frequency and distance of the source.
It should be noted that an accurate estimate of size requires some knowledge of the emissivity, particularly its spectral and angular dependence.
Note that this quantity has no angular dependence.
Small spherical particles will show no angular dependence, hence no anisotropy.