Structure
The link is created with two projections of the unknot: one circular loop and one figure eight-shaped loop (i.e., a loop with a Reidemeister Type I move applied) intertwined such that they are inseparable and neither loses its form. Excluding the instance where the figure eight thread intersects itself, the Whitehead link has four crossings. Because each underhand crossing has a paired upperhand crossing, its linking number is 0. It is not isotopic to the unlink, but it is link homotopic to the unlink.
In braid theory notation, the link is written
Its Jones polynomial is
This polynomial and are the two factors of the Jones polynomial of Marilyn's Cross. (Note that is the Jones polynomial for the mirror image of a link having Jones polynomial .)
Read more about this topic: Whitehead Link
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