48 citations · 75 across the 10 of their papers we have counts for
11 papers · 1 filter
Lattices in $\R^n\rtimes\SL_2(\R)$
M. M. Radhika, Sandip Singh
We determine the existence of cocompact lattices in groups of the form $\V\rtimes\SL_2(\R)$, where $\V$ is a finite dimensional real representation of $\SL_2(\R)$. It turns out tha…
Thinness of some hypergeometric groups in Sp(6)
Sandip Singh, Shashank Vikram Singh
We show that the hypergeometric groups corresponding to the seven pairs of the parameters , where = (0, 0, 0, 0, 0, 0) and is any of the parameters (1/2, 1/2, 1/2, 1…
Arithmeticity of Some Hypergeometric Groups
Jitendra Bajpai, Sandip Singh, Shashank Vikram Singh
We show that the hypergeometric groups associated to the pairs of the parameters , $\left(\frac{1}{2},\frac{1}{2},\frac{1}{4},\frac{3}{4}…
Symplectic Hypergeometric Groups of Degree Six
Jitendra Bajpai, Daniele Dona, Sandip Singh +1
Our computations show that there is a total of pairs of degree six coprime polynomials where , is a product of cyclotomic polynomials, and $f,…
On Orthogonal Hypergeometric Groups of Degree Five
Jitendra Bajpai, Sandip Singh
A computation shows that there are 77 (up to scalar shifts) possible pairs of integer coefficient polynomials of degree five, having roots of unity as their roots, and satisfying t…
Commensurability and arithmetic equivalence for orthogonal hypergeometric monodromy groups
Jitendra Bajpai, Sandip Singh, Scott Thomson
We compute invariants of quadratic forms associated to orthogonal hypergeometric groups of degree five. This allows us to determine some commensurabilities between these groups, as…
Arithmeticity of Some Hypergeometric Monodromy Groups in Sp(4)
Sandip Singh
The article [14] gives a list of 51 symplectic hypergeometric monodromy groups corresponding to primitive pairs of degree four polynomials, which are products of cyclotomic polynom…
Orthogonal Hypergeometric Groups with a Maximally Unipotent Monodromy
Sandip Singh
Similar to the symplectic cases, there is a family of fourteen orthogonal hypergeometric groups with a maximally unipotent monodromy (cf. Table 1.1). We show that two of the fourte…
Arithmeticity of Four Hypergeometric Monodromy Groups associated to Calabi-Yau threefolds
Sandip Singh
In [12], we show that 3 of the 14 hypergeometric monodromy groups associated to Calabi-Yau threefolds, are arithmetic. Brav-Thomas (in [3]) show that 7 of the remaining 11, are thi…
Coxeter Groups are not higher rank Arithmetic Groups
Sandip Singh
Let W be an irreducible finitely generated Coxeter group. The geometric representation of W in GL(V) provides a discrete embedding in the orthogonal group of the Tits form (the ass…
Arithmeticity of Certain Symplectic Hypergeometric Groups
Sandip Singh, Tyakal N. Venkataramana
We give a sufficient condition on a pair of (primitive) integral polynomials that the associated hypergeometric group (monodromy group of the corresponding hypergeometric different…