Notes for AKT-090910-2/0:15:44: Difference between revisions
From Drorbn
Jump to navigationJump to search
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
Definitions of positive and negative crossings and the writhe of an oriented knot diagram. |
Definitions of positive and negative crossings and the writhe of an oriented knot diagram. |
||
:Positive crossing: <math>\overcrossing</math> |
:Positive crossing: <math>\,\overcrossing\,</math> |
||
:Negative crossing: <math>\undercrossing</math> |
:Negative crossing: <math>\,\undercrossing\,</math> |
||
:The <b>writhe</b> of an oriented knot diagram is the sum of the signs of all the crossings in the diagram. |
:The <b>writhe</b> of an oriented knot diagram is the sum of the signs of all the crossings in the diagram. |
||
Latest revision as of 14:38, 8 September 2011
Definitions of positive and negative crossings and the writhe of an oriented knot diagram.
- Positive crossing: [math]\displaystyle{ \,\overcrossing\, }[/math]
- Negative crossing: [math]\displaystyle{ \,\undercrossing\, }[/math]
- The writhe of an oriented knot diagram is the sum of the signs of all the crossings in the diagram.
