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Polarized Electrons

Electrons, like visible light, can be polarized.  They have an intrinsic spin (angular momentum) which can be oriented parallel (right-handed polarization) or anti-parallel (left-handed polarization) to their momentum direction.  In a similar way that polaroid sunglasses transmit vertically-polarized light preferentially to horizontally-polarized light, the strength of the weak nuclear force (unlike the electromagnetic force or the strong nuclear force) is different for right-handed and left-handed particles.  Neutral Z particles and charged W+ and W-  particles transmit the weak force (radioactivity is an example of a weak force interaction) and do so with different strengths for right-handed and left-handed particles.  The W+ and W- interact only with left-handed particles, while the Z interacts with both but with different strengths.  This left-right asymmetry in weak interactions is known as parity violation


Last Update: 11 Dec 2004