Let f(x) ∈ [x] be a monic irreducible reciprocal polynomial of degree 2d with roots r1, 1/r1, r2, 1/r2, . . ., rd, 1/rd. The corresponding trace polynomial g(x) of degree d is the polynomial whose roots are r1 + 1/r1, . . ., rd + 1/rd. If the Galois groups of f and g are Gf and Gg respectively, then Gg ≅ Gf/N, where N is isomorphic to a subgroup of C2d. In a naive sense, the generic case is Gf ≅ C2d ⋊ Sd, with N ≅ C2d and Gg ≅ Sd. When f(x) has extra structure this may be reflected in the Galois group, and it is not always true even that Gf ≅ N ⋊ Gg. For example, for cyclotomic polynomials f(x) = Φn(x) it is known that Gf ≅ N ⋊ Gg if and only if n is divisible either by 4 or by some prime congruent to 3 modulo 4.

In this paper we deal with irreducible reciprocal monic polynomials f(x) ∈ [x] that are ‘close’ to being cyclotomic, in that there is one pair of real positive reciprocal roots and all other roots lie on the unit circle. With the further restriction that f(x) has degree at least 4, this means that f(x) is the minimal polynomial of a Salem number. We show that in this case one always has Gf ≅ N ⋊ Gg, and moreover that N ≅ C2d or C2d−1, with the latter only possible if d is odd.

A strictly real unital Banach algebra is one in which every element has real spectrum. An antilattice partial order and its associated open-interval topology are defined on by taking as positive cone the principal component of the maximal group of the algebra, and their properties are studied. The topology coincides with the semimetric topology of the spectral radius, which is a seminorm, making into a locally convex partially ordered topological algebra with continuous inversion and normal cone. Every positive element has a unique positive square root, and logarithm, and these functions and exp are continuous and monotone. The cone has the same closure in both open-interval and normal topologies, the closure being a wedge for an associated preorder on , this preorder coinciding with the preorder of Kelley and Vaught. The partial order and the associated preorder have the same dual cone. There is a modified Gelfand representation for (possibly non-commutative) , and a boundary integral representation for functionals in the order dual. The compact convex subset in the dual is metrizable if the cone of the partial order in is separable.

In this paper we obtain generating functions of Jacobi polynomials. The results obtained are of general character and include as particular cases of the results given earlier by Bailey ((1), p. 102, Ex. 19) and Brafman (2).

The theory of generalized symmetric spaces was begun by P. J. Graham and A. J. Ledger in 1967 in their paper [1]. Other authors who contributed to this topic were, e.g. F. Brickel, A. Deicke, A. S. Fedenko, A. Gray, V. G. Kac, M. Obata, B. Pettit, K. Sekigawa and J. Wolf; more recently also J. A. Jiménez, A. R. Razawi, C. Sánchez, M. Sekizawa, M. Toomanian, G. Tsagas and L. Vanhecke. A systematic exposition is given in the book by O. Kowalski[3, 4]. The author classifies all generalized symmetric Riemannian spaces in dimension n ≤ 5, using a systematic method.

A tangle is a pair of strings (t0, t1) properly embedded in a 3-ball. Tangles have been used in several approaches to the classification of knots (see [1, 4, 15]). In these investigations, one keeps track of the endpoints of the arcs, so that the sum of two tangles along their boundaries is well defined. In particular, the sum of a given tangle with a trivial tangle, and any invariants of the resulting link, are invariants of the tangle under the restricted relation of isotopy keeping the endpoints fixed.

Suppose that a, c and A are real, and that

Let n (X) be the number of zeros of

in ; then it is not difficult to prove that

for some K = K (A, a, c, θ). The problem in this paper is to determine the function K explicitly in terms of its variables.

In the theory of beta-decay, as is well known, when the electron is described by relativistic wave-functions, e.g. in a Coulomb field, a difficulty arises when these become infinite at the centre of force, r = 0. The wave-functions are then evaluated at the nuclear radius, r = R, and in many formulae there appears (1) a rather sensitive dependence on R. For the capture of an orbital electron by a nucleus the results of calculation depend strongly on the behaviour of the wave-function of the bound electron near the nucleus. The nature of the potential energy near the nucleus will thus affect such quantities as the ratio of K-capture to positron emission. Wannier (2) has discussed a similar problem for the Schrödinger equation, but the singular behaviour of the solutions of the Dirac equation for the ground state makes it desirable to have the solution for the relativistic case. In the following, relativistic wave-functions are derived and used for a potential energy which is Coulombian outside the nucleus and constant inside. Similar problems have been considered by others, Breit et al. (3), Racah (4), in application to the calculation of hyperfine structure, and also by Broch (5).

Let S be a Sperner set of subsets of {1, 2, …, n}. (That is, for A, B ∈ S, if A ≠ B then A ⊄ B and B ⊄ A.) Then

In an earlier paper the problem of the interpolation of an integral function f(z) in terms of the values taken on a sequence zn was studied by means of generalized σ-functions with zeros at zn. The purpose of the present paper is to show that the methods used in I can be modified to deal with functions of finite order and type in the angle Sα, | arg z | ≤ α. There is even a considerable saving since, for an Sα with α < π, we can escape from the awkward convergence condition Dρ (ii) of I. Most of our results, and to a great extent also their proofs, are direct generalizations of well-known results for the lattice points m + in (cf. the references at the end of I, particularly (2), (5), (6), (14), (18)).

We define the symmetric Auslander category As(R) to consist of complexes of projective modules whose left- and right-tails are equal to the left- and right-tails of totally acyclic complexes of projective modules.

The symmetric Auslander category contains A(R), the ordinary Auslander category. It is well known that A(R) is intimately related to Gorenstein projective modules, and our main result is that As(R) is similarly related to what can reasonably be called Gorenstein projective homomorphisms. Namely, there is an equivalence of triangulated categorieswhere GMor(R) is the stable category of Gorenstein projective objects in the abelian category Mor(R) of homomorphisms of R-modules.

This result is set in the wider context of a theory for As(R) and Bs(R), the symmetric Bass category which is defined dually.

A Möbius transformation z → (az + b)/(cz + d), ad — bc = 1, acts as a conformal transformation of the Riemann sphere , and its Poincaré extension acts as an isometry of hyperbolic 3-space modelled in the ball < 1. The size of this transformation can be measured by the matrix norm

or by the hyperbolic distance ρ through which its extension moves the point (0, 0, 0).

Given a 2-stranded tangle T contained in a ℤ-homology ball Y, we investigate the character variety R(Y, T) of conjugacy classes of traceless SU(2) representations of π1(Y \ T). In particular we completely determine the subspace of binary dihedral representations, and identify all of R(Y, T) for many tangles naturally associated to knots in S3. Moreover, we determine the image of the restriction map from R(T, Y) to the traceless SU(2) character variety of the 4-punctured 2-sphere (the pillowcase). We give examples to show this image can be non-linear in general, and show it is linear for tangles associated to pretzel knots.

The cohomology ring of the flag manifold associated to any compact Lie group has a simple description in terms of the Weyl group of $G$. The same algebraic procedure gives a ring associated to any complex re ection group, not necessarily a Weyl group, but much less is known about it. For example, in the case of Weyl groups (and the corresponding compact Lie groups), there are remarkably simple formulas for the degrees of Grassmannians and related projective varieties, due to Schubert and others. We find here a similar formula for the ‘degree’ of a ring associated to the complex re ection group $S_n**{\bf Z}/e$; in the case $e = 2$, this group is the Weyl group of the symplectic group and our formula specializes to the classical formula for the degree of the isotropic Grassmannian $Sp(2n)/U(n)$. We discuss the relation of our calculation to Hall–Littlewood polynomials at roots of unity.

In a previous paper (11) refractive index profiles capable of yielding exact solutions for vertically polarized electromagnetic waves propagating in horizontally stratified isotropic media were derived systematically. The present work extends the method to deal with anisotropic media in which propagation is transverse to a horizontally applied static magnetic field. The relevance to ELF radio wave propagation in the terrestrial ionosphere is noted.

We give sufficient conditions for the existence of detecting elements for the Lusternik–Schnirelmann category in proper homotopy. As an application we determine the proper LS category of some semistable one-ended open 3-manifolds.

1. Introduction. Using throughout the definitions and notations contained in (4), we state the following recent results by one of the present authors ((4), Theorem I and Theorem 2) which include as a special case the corresponding |C| – result due to Bosanquet (1), Bosanquet and Hyslop (2) and Hyslop(5).

Consider actions of a reductive complex Lie group G on an analytic space germ (X, 0). In a previous paper [16] we proved that such an action is determined uniquely (up to conjugation with an automorphism of (X, 0)) by the induced action of G on the tangent space of (X, 0). Here it will be shown that every deformation of such an action, parametrized holomorphically by a reduced analytic space germ, is trivial, i.e. can be obtained from the given action by conjugation with a family of automorphisms of (X, 0) depending holomorphically on the parameter. (For a more precise formulation in terms of actions on analytic ℂ-algebras, see Theorem 2 below. An analogue for actions on formal ℂ-algebras is given there too.)

Let G be a non-discrete locally compact topological group. A construction is given for a self-adjoint measure μ on G that has independent powers, and is, moreover, in the sub-algebra M0(G) of M(G). From this, the asymmetry of M0(G) (and of M(G) itself) is immediate.

We generalize the Carathéodory version of the Schwarz reflection principle for pseudo-metrics

formula here

where w is analytic in some domain of the complex plane, [mid ] w [mid ] < 1 and use a unit disk version of the new result to study certain homeomorphisms of the unit ball in [Hscr ]([ ]) onto itself.