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Let l be an odd prime and K/k a Galois extension of totally real number fields with Galois group G such that K/k_\infty and k/Q are finite. We reduce the conjectured triviality of the reduced Whitehead group SK_1(QG) of the algebra…

Number Theory · Mathematics 2011-09-27 Irene Lau

A theory T is tight if different deductively closed extensions of T (in the same language) cannot be bi-interpretable. Many well-studied foundational theories are tight, including PA [Visser2006], ZF, Z2, and KM [enayat2017]. In this…

Logic · Mathematics 2023-05-16 Alfredo Roque Freire , Kameryn J. Williams

A completeness conjecture is advanced concerning the free small-colimit completion P(A) of a (possibly large) category A. The conjecture is based on the existence of a small generating-cogenerating set of objects in A. We sketch how the…

Category Theory · Mathematics 2009-09-29 Brian J. Day

In the present paper we prove Liouville-type theorems: non-existence theorems for complete twisted and warped products of Riemannian manifolds which generalize and complement similar results for compact manifolds.

Differential Geometry · Mathematics 2016-08-15 Sergey Stepanov

We study the compactification of the $(2,0)$ and type-II little-string theories on $S^1$, $T^2$ and $T^3$ with an R-symmetry twist that preserves half the supersymmetry. We argue that it produces the same moduli spaces of vacua as…

High Energy Physics - Theory · Physics 2009-10-31 Yeuk-Kwan E. Cheung , Ori J. Ganor , Morten Krogh

We present some results related to theorems of Pasynkov and Torunczyk on the geometry of maps of finite dimensional compacta.

General Topology · Mathematics 2007-05-23 Michael Levin , Wayne Lewis

Using elementary algebraic arguments, it is shown that $SU(2)^{m}:=SU(2)\times \cdots \times SU(2)$ ($m$ times) admits no left-invariant hypercomplex structures for all $m\ge 1$. This result answers (in a clear and easily accessible way)…

Differential Geometry · Mathematics 2025-09-05 David N. Pham

Assuming that Iwasawa's $\mu_{K/k}$-invariant vanishes, we prove the 'main conjecture' of equivariant Iwasawa theory, at odd prime numbers $l$, for arbitrary extensions $K/k$ of totally real number fields, up to its uniqueness assertion.

Number Theory · Mathematics 2010-04-30 Jürgen Ritter , Alfred Weiss

The Atiyah conjecture for a discrete group G states that the $L^2$-Betti numbers of a finite CW-complex with fundamental group G are integers if G is torsion-free and are rational with denominators determined by the finite subgroups of G in…

Group Theory · Mathematics 2018-11-28 Peter Linnell , Thomas Schick

After recalling the various tautological algebras of the moduli space of curves and some of its partial compactifications and stating several well-known results and conjectures concerning these algebras, we prove that the natural extension…

Algebraic Geometry · Mathematics 2012-06-21 Carel Faber

Webb's conjecture states that the orbit space of the Brown complex of a finite group at any given prime $\ell$ is contractible. This conjecture was proved by Symonds in 1998. In this paper, we suggest a generalisation of Webb's conjecture…

Representation Theory · Mathematics 2024-08-13 Damiano Rossi

We produce infinitely many finite 2-groups that do not embed with index 2 in any group generated by involutions. This disproves a conjecture of Lemmermeyer and restricts the possible Galois groups of unramified 2-extensions, Galois over the…

Number Theory · Mathematics 2007-05-23 Nigel Boston , Charles Leedham-Green

We prove that the finitistic dimension conjecture, the Gorenstein Symmetry Conjecture, the Wakamatsu-tilting conjecture and the generalized Nakayama conjecture hold for artin algebras which can be realized as endomorphism algebras of…

Representation Theory · Mathematics 2008-04-14 Jiaqun Wei

We show that for non-conjugate subgroups $G_1$ and $G_2$ of a finite group $G$ there exists an extension of $G$ (by a finite group) in which the pre-images of $G_1$ and $G_2$ are not isomorphic. This allows us to show that $\mathbb Z$-coset…

Group Theory · Mathematics 2026-05-06 Ido Karshon , Alexander Lubotzky , D. B. McReynolds , Alan W. Reid , Mark Shusterman

We study compactifications of Type IIB string theory on a K3 \times T^2/Z_2 orientifold in the presence of RR and NS flux. We find the most general supersymmetry preserving, Poincare invariant, vacua in this model. All the complex structure…

High Energy Physics - Theory · Physics 2010-11-19 Prasanta K. Tripathy , Sandip P. Trivedi

In 1993, Lubotzky and Weiss conjectured that if a compact group admits two finitely generated dense subgroups, one of which is amenable and the other has Kazhdan's property (T), then it would be finite. This conjecture was resolved in the…

Group Theory · Mathematics 2019-04-26 Masato Mimura

We prove a complex polynomial plank covering theorem for not necessarily homogeneous polynomials. As the consequence of this result, we extend the complex plank theorem of Ball to the case of planks that are not necessarily centrally…

Metric Geometry · Mathematics 2024-05-28 Alexey Glazyrin , Roman Karasev , Alexandr Polyanskii

We prove several results giving lower bounds for the large cardinal strength of a failure of the singular cardinal hypothesis. The main result is the following theorem: Theorem: Suppose $\kappa$ is a singular strong limit cardinal and…

Logic · Mathematics 2016-09-06 Moti Gitik , William Mitchell

The aim of the present paper is to give evidence, largely numerical, in support of the non-commutative main conjecture of Iwasawa theory for the motive of a primitive modular form of weight k>2 over the Galois extension of Q obtained by…

Number Theory · Mathematics 2013-09-24 John Coates , Tim Dokchitser , Zhibin Liang , William Stein , Ramdorai Sujatha

We prove the boundedness of complements modulo two conjectures: Borisov-Alexeev conjecture and effective adjunction for fibre spaces. We discuss the last conjecture and prove it in two particular cases.

Algebraic Geometry · Mathematics 2010-04-26 Yu. G. Prokhorov , V. V. Shokurov