Yau's conjecture on the first eigenvalue

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In mathematics, Yau's conjecture on the first eigenvalue is, as of 2018, an unsolved conjecture proposed by Shing-Tung Yau in 1982. It asks:

Is it true that the first eigenvalue for the Laplace–Beltrami operator on an embedded minimal hypersurface of

Sn+1

is

n

?

If true, it will imply that the area of embedded minimal hypersurfaces in S3 will have an upper bound depending only on the genus.

Some possible reformulations are as follows:

  • The first eigenvalue of every closed embedded minimal hypersurface

    Mn

    in the unit sphere

    Sn+1

    (1) is

    n
  • The first eigenvalue of an embedded compact minimal hypersurface

    Mn

    of the standard (n + 1)-sphere with sectional curvature 1 is

    n
  • If

    Sn+1

    is the unit (n + 1)-sphere with its standard round metric, then the first Laplacian eigenvalue on a closed embedded minimal hypersurface

    nSn+1

    is

    n

The Yau's conjecture is verified for several special cases, but still open in general.

Shiing-Shen Chern conjectured that a closed, minimally immersed hypersurface in Sn+1(1), whose second fundamental form has constant length, is isoparametric. If true, it would have established the Yau's conjecture for the minimal hypersurface whose second fundamental form has constant length.

A possible generalization of the Yau's conjecture:

Let

Md

be a closed minimal submanifold in the unit sphere

SN+1

(1) with dimension

d

of

Md

satisfying

d23n+1

. Is it true that the first eigenvalue of

Md

is

d

?

Further reading