The higher-girth face-number conjecture for simplicial complexes

Let Γ\Gamma be a (d1)(d-1)-dimensional simplicial complex with nn vertices. Let fi1(Γ)f_{i-1}(\Gamma) denote the number of (i1)(i-1)-dimensional faces, and let grp1(Γ)\operatorname{gr}_{p-1}(\Gamma) denote its (p1)(p-1)-girth. For some integers p,r2p,r\geq 2, assume that grp1(Γ)>2p+2r4\operatorname{gr}_{p-1}(\Gamma)>2p+2r-4. Let ap,r,ia_{p,r,i} be the recursively defined exponents

a2,r,i=1+1/r++1/ri1,a_{2,r,i}=1+1/r+\ldots+1/r^{i-1}, ap,r,p1=p1,a_{p,r,p-1}=p-1, ap,r,i=12ap1,r,i1+12ap,r,i1+1(p3,ip).a_{p,r,i}=\frac{1}{2}a_{p-1,r,i-1}+\frac{1}{2}a_{p,r,i-1}+1\quad (p\geq 3, i\geq p).

The higher-girth face-number conjecture. There is a constant Cp,r,iC_{p,r,i} depending only on p,r,ip,r,i such that

fi1(Γ)Cp,r,idiap,r,inap,r,i.f_{i-1}(\Gamma)\leq C_{p,r,i}d^{i-a_{p,r,i}}n^{a_{p,r,i}}.

The conjecture seeks upper bounds for face numbers from the dimension, number of vertices, and (p1)(p-1)-girth. The recursively defined exponents increase with the relevant parameters and approach 2p3+1/(r1)2p-3+1/(r-1) as ii tends to infinity; the asserted bound is not established in the supplied text.

Sources & referencesView supporting material

Primary source

Michael Goff, “Higher dimensional Moore bounds”, arXiv:0906.0763 (2009).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.