- Library Home /
- Search Collections /
- Open Collections /
- Browse Collections /
- BIRS Workshop Lecture Videos /
- Reconnection In Biology and Physics
Open Collections
BIRS Workshop Lecture Videos
BIRS Workshop Lecture Videos
Reconnection In Biology and Physics Sumners, DeWitt
Description
Reconnection is an important event in many areas of science, including site- specific DNA recombination and the reconnection of field lines in astro- and plasma physics. We will discuss the conservation of writhe in a reconnection, and the behavior of twist in site-specific DNA recombination. Using the theorem of Moffatt and Ricca (Proc. Roy. Soc. 1992), the helicity of a magnetic flux tube can be calculated in terms of the writhe of the centerline and the twist of the ribbon determined by the centerline and one of the other field lines in the flux tube tube. This talk will present the proof of the following:\\r\\nTheorem: Given a reconnection event between a pair of magnetic flux tubes of identical flux, suppose that the twist of the reconnected tube is the sum of the twists of the individual tubes. Then helicity is conserved by the reconnection event — the helicity of the reconnected flux tube is the sum of the helicities of the individual tubes. Any deviation from helicity conservation is entirely due to twist inserted locally at the reconnection site (the writhe component of helicity is always conserved). This is joint with Christian Laing and Renzo Ricca.\\r\\n
Item Metadata
Title |
Reconnection In Biology and Physics
|
Creator | |
Publisher |
Banff International Research Station for Mathematical Innovation and Discovery
|
Date Issued |
2013-11-21
|
Description |
Reconnection is an important event in many areas of science, including site- specific DNA recombination and the reconnection of field lines in astro- and plasma physics. We will discuss the conservation of writhe in a reconnection, and the behavior of twist in site-specific DNA recombination. Using the theorem of Moffatt and Ricca (Proc. Roy. Soc. 1992), the helicity of a magnetic flux tube can be calculated in terms of the writhe of the centerline and the twist of the ribbon determined by the centerline and one of the other field lines in the flux tube tube. This talk will present the proof of the following:\\r\\nTheorem: Given a reconnection event between a pair of magnetic flux tubes of identical flux, suppose that the twist of the reconnected tube is the sum of the twists of the individual tubes. Then helicity is conserved by the reconnection event — the helicity of the reconnected flux tube is the sum of the helicities of the individual tubes. Any deviation from helicity conservation is entirely due to twist inserted locally at the reconnection site (the writhe component of helicity is always conserved). This is joint with Christian Laing and Renzo Ricca.\\r\\n
|
Extent |
27 minutes
|
Subject | |
Type | |
File Format |
video/mp4
|
Language |
eng
|
Notes |
Author affiliation: Florida State University
|
Series | |
Date Available |
2014-10-11
|
Provider |
Vancouver : University of British Columbia Library
|
Rights |
Attribution-NonCommercial-NoDerivs 2.5 Canada
|
DOI |
10.14288/1.0044065
|
URI | |
Affiliation | |
Peer Review Status |
Unreviewed
|
Scholarly Level |
Faculty
|
Rights URI | |
Aggregated Source Repository |
DSpace
|
Item Media
Item Citations and Data
Rights
Attribution-NonCommercial-NoDerivs 2.5 Canada