How The Most Useless Branch of Math Could Save Your Life

Veritasium2 minutes read

One type of knot is superior as it doesn't loosen easily, and knot theory studies different knots that are integral to various structures. Mathematicians have developed polynomials and algorithms to distinguish and identify knots, with applications in fields ranging from material science to biology and cancer treatment.

Insights

  • Knot theory, a mathematical branch, studies different knots on closed loops with applications in protein structure, DNA, and material design, showcasing the complexity and importance of knots in various scientific disciplines.
  • Various knot invariants like the Alexander polynomial, Jones polynomial, and HOMFLY polynomial are crucial tools in uniquely identifying knots, highlighting the intricate mathematical techniques used to distinguish between different knot structures and their applications in diverse fields beyond mathematics.

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Recent questions

  • What are the two ways to tie a knot in shoe laces?

    There are two ways to tie a knot in shoe laces: counterclockwise and clockwise. The counterclockwise knot is considered superior as it doesn't loosen easily.

  • What is the simplest knot in knot theory?

    The simplest knot in knot theory is an unknot, which is a closed loop with no crossings.

  • Who developed a computer algorithm to distinguish knots?

    Mathematician Wolfgang Haken developed a computer algorithm to distinguish knots, advancing knot theory research.

  • What are some applications of knot theory?

    Knot theory has applications in creating new materials, understanding DNA structure, and even in cancer treatment, showcasing its diverse relevance in various fields.

  • How can headphones be prevented from knotting in pockets?

    To prevent headphones from knotting in pockets, it is recommended to restrict their movement by using a small box or increasing the stiffness of the string, reducing the likelihood of knots forming.

Related videos

Summary

00:00

"Exploring Knot Theory in Mathematics and Science"

  • There are two ways to tie a knot in shoe laces: counterclockwise and clockwise.
  • One of these knots is far superior as it doesn't loosen easily.
  • Knot theory is a branch of mathematics that studies different knots.
  • Knot theory is integral to the structure of proteins, DNA, and new materials.
  • All knots exist on closed loops, with the simplest knot being an unknot.
  • Knot equivalence problem is the challenge of distinguishing between different knots.
  • Scottish physicist Peter Guthrie Tait's work on knots led to advancements in knot theory.
  • German mathematician Kurt Reidemeister's theorem simplified knot transformations.
  • Mathematician Wolfgang Haken developed a computer algorithm to distinguish knots.
  • In 2011, mathematicians found an upper bound solution to the knot equivalence problem using tetration.

15:07

"Knot Theory: Tricolorability to Polynomials and Beyond"

  • Tricolorability is a property of knots where each intersection must have three colors, maintained through Reidemeister moves.
  • The trefoil knot is tricolorable, while the unknot is not, allowing for their differentiation.
  • Tricolorability expands into p-colorability, where strands are numbered with integers and specific rules must be followed at crossings.
  • The Alexander polynomial is a knot invariant discovered in 1923, providing relationships between knots based on variations at crossings.
  • The Jones polynomial, discovered in 1984, is a more specific knot invariant that distinguishes many more knots than the Alexander polynomial.
  • The HOMFLY polynomial, an improved version of the Jones polynomial, was independently discovered by six mathematicians and later by two Polish mathematicians.
  • Knot invariants, like polynomials, are used together to uniquely identify knots, with dozens of invariants needed for accurate identification.
  • The Perko pair, initially thought to be different knots, were later proven to be the same through Reidemeister moves.
  • Tabulating knots up to 10 crossings took decades, with John Conway tabulating all 11 crossings in a single afternoon.
  • Knot theory extends to chemistry and biology, with applications in creating new materials and understanding biological processes like DNA replication and cancer treatment.

30:01

"Preventing Knots: Agitation, Space, and Theory"

  • Longer agitation time and longer string increase the likelihood of knotting, but confining the string in a small space decreases this probability.
  • To prevent headphones from knotting in pockets, restrict their movement by using a small box or increasing string stiffness.
  • A model for knot formation involves loops forming when a string is agitated in a container, with the free end weaving through the loops to create knots.
  • Knot theory has evolved from a failed theory of everything to a tool applicable in various fields, from material science to chemotherapy, showcasing the interconnectedness of knowledge.
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