Upper and lower bounds and modulus of continuity of decomposed M\"{o}bius energies

Aya Ishizeki; Takeyuki Nagasawa

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arXiv · 2002.09153

Upper and lower bounds and modulus of continuity of decomposed M\"{o}bius energies

Aya Ishizeki·Takeyuki Nagasawa

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Abstract

The M\"{o}bius energy is one of the knot energies, and is named after its M\"{o}bius invariant property. It is known to have several different expressions. One is in terms of the cosine of conformal angle, and is called the cosine formula. Another is the decomposition into M\"{o}bius invariant parts, called the decomposed M\"{o}bius energies. Hence the cosine formula is the sum of the decomposed energies. This raises a question. Can each of the decomposed energies be estimated by the cosine formula~? Here we give an affirmative answer: the upper and lower bounds, and modulus of continuity of decomposed parts can be evaluated in terms of the cosine formula. In addition, we provide estimates of the difference in decomposed energies between the two curves in terms of M\"{o}bius invariant quantities.

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Aya Ishizeki, Takeyuki Nagasawa. 2020-02-21. Upper and lower bounds and modulus of continuity of decomposed M\"{o}bius energies. https://arxiv.org/abs/2002.09153

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