Britney Gallivan
Encyclopedia
Britney Crystal Gallivan (born 1985) of Pomona, California
, is best known for determining the maximum number of times which paper or other materials can be folded.
in half 12 times. She calculated that instead of folding in half every other direction, the least volume of paper to get 12 folds would be to fold in the same direction, using a very long sheet of paper. A special kind of $85-per-roll toilet paper met her length requirement. Not only did she provide the empirical proof, but she also derived an equation that yielded the width of paper or length of paper necessary to fold a piece of paper of thickness t any n number of times.
She was a keynote speaker at the September 22, 2006 National Council of Teachers of Mathematics
convention.
In 2007, Gallivan graduated from UC Berkeley
with a degree in Environmental Science from the College of Natural Resources.
For single-direction folding (using a long strip of paper), the exact required strip length L is
where t represents the thickness of the material to be folded, W is the width of a square piece of paper, L is the length of a paper piece to be folded in only one direction and n represents the number of folds desired.
These equations show that in order to fold anything in half, it must be
times longer than its thickness, and that depending on how something is folded, the amount its length decreases with each fold differs.
, She served as a consultant and was mentioned in an episode of MythBusters
on the Discovery Channel
in 2007, and in episode 3 of QI
s "F" series.
Pomona, California
-2010:The 2010 United States Census reported that Pomona had a population of 149,058, a slight decline from the 2000 census population. The population density was 6,491.2 people per square mile...
, is best known for determining the maximum number of times which paper or other materials can be folded.
Biography
In January 2002, while a junior in high school, Gallivan demonstrated that a single piece of toilet paper, 4000 ft (1200 m) in length, can be folded in half twelve times. This was contrary to the popular conception that the maximum number of times any piece of paper could be folded in half was seven. Gallivan succeeded in folding a very long sheet of toilet paperToilet paper
Toilet paper is a soft paper product used to maintain personal hygiene after human defecation or urination. However, it can also be used for other purposes such as blowing one's nose when one has a cold or absorbing common spills around the house, although paper towels are more used for the latter...
in half 12 times. She calculated that instead of folding in half every other direction, the least volume of paper to get 12 folds would be to fold in the same direction, using a very long sheet of paper. A special kind of $85-per-roll toilet paper met her length requirement. Not only did she provide the empirical proof, but she also derived an equation that yielded the width of paper or length of paper necessary to fold a piece of paper of thickness t any n number of times.
She was a keynote speaker at the September 22, 2006 National Council of Teachers of Mathematics
National Council of Teachers of Mathematics
The National Council of Teachers of Mathematics was founded in 1920. It has grown to be the world's largest organization concerned with mathematics education, having close to 100,000 members across the USA and Canada, and internationally....
convention.
In 2007, Gallivan graduated from UC Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...
with a degree in Environmental Science from the College of Natural Resources.
Paper folding theorem
An upper bound and a close approximation of the actual paper width needed for alternate-direction folding isFor single-direction folding (using a long strip of paper), the exact required strip length L is
where t represents the thickness of the material to be folded, W is the width of a square piece of paper, L is the length of a paper piece to be folded in only one direction and n represents the number of folds desired.
These equations show that in order to fold anything in half, it must be
times longer than its thickness, and that depending on how something is folded, the amount its length decreases with each fold differs.In popular culture
Gallivan's story was mentioned in the episode Identity Crisis of Numb3rsNUMB3RS
Numb3rs is an American television drama which premiered on CBS on January 23, 2005, and concluded on March 12, 2010. The series was created by Nicolas Falacci and Cheryl Heuton, and follows FBI Special Agent Don Eppes and his mathematical genius brother, Charlie Eppes , who helps Don solve crimes...
, She served as a consultant and was mentioned in an episode of MythBusters
MythBusters
MythBusters is a science entertainment TV program created and produced by Beyond Television Productions for the Discovery Channel. The series is screened by numerous international broadcasters, including Discovery Channel Australia, Discovery Channel Latin America, Discovery Channel Canada, Quest...
on the Discovery Channel
Discovery Channel
Discovery Channel is an American satellite and cable specialty channel , founded by John Hendricks and distributed by Discovery Communications. It is a publicly traded company run by CEO David Zaslav...
in 2007, and in episode 3 of QI
QI
QI is a British comedy panel game television quiz show created and co-produced by John Lloyd, hosted by Stephen Fry, and featuring permanent panellist Alan Davies. Most of the questions are extremely obscure, making it unlikely that the correct answer will be given...
s "F" series.
External links
- Historical Society of Pomona Valley Page
- Folding at MathWorld
- Entry for the folding function at the On-Line Encyclopedia of Integer SequencesOn-Line Encyclopedia of Integer SequencesThe On-Line Encyclopedia of Integer Sequences , also cited simply as Sloane's, is an online database of integer sequences, created and maintained by N. J. A. Sloane, a researcher at AT&T Labs...