AKT-09/HW3

From Drorbn
Revision as of 18:11, 16 November 2009 by Drorbn (talk | contribs)
Jump to navigationJump to search

Solve the following problems and submit them in class by November 24, 2009:

Problem 1 With [math]\displaystyle{ T }[/math], [math]\displaystyle{ B^+ }[/math] and [math]\displaystyle{ R }[/math] as below, write [math]\displaystyle{ B^+ }[/math] as a composition of [math]\displaystyle{ T }[/math] and two [math]\displaystyle{ R }[/math]'s, using he basic TG operations [math]\displaystyle{ d_e }[/math], [math]\displaystyle{ u_e }[/math], and [math]\displaystyle{ \# }[/math].

AKT-09-TBR.png

Problem 2 Show that the "topological boundary" operator [math]\displaystyle{ \partial_T }[/math] and the "crossing change" operator [math]\displaystyle{ x_T }[/math] of the class of November 5 are compositions of the basic TG operations [math]\displaystyle{ d_e }[/math], [math]\displaystyle{ u_e }[/math], and [math]\displaystyle{ \# }[/math] (you are also allowed to use "nullary" operations, otherwise known as "constants").

Problem 3 Write the third Reidemeister move R3 as a relation on [math]\displaystyle{ Z(B_+) }[/math].