We give canonical matrices of a pair (A,B) consisting of a nondegenerate form B and a linear operator A satisfying B(Ax,Ay) = B(x, y) on a vector space over F in the following cases: • F is an algebraically closed field of characteristic different from 2 or a real closed field, and B is symmetric or skew-symmetric; • F is an algebraically closed field of characteristic 0 or the skew field of qu...

1. If X is a real Banach space and X** the second conjugate space of X, then for each subset A of X** let KxiA) be the «¿"-sequential closure of A in X**; thus FEKxiA) if and only if there is a sequence { Fn} in A such that F(f) = limn F„(f) for all/EX*. If Jx is the canonical mapping from X into X**, then Kx(JxX) is closed in the norm topology of X** [l]. In the present paper it will be shown ...

One definition of a hyperelliptic curve is a curve C over an algebraically closed field k whose function field K is a degree 2 extension of a purely transcendental extension of k. 1. (a) Show that every hyperelliptic curve is birational to a curve of the form y 2 = f (x) where f ∈ k[x] is a monic squarefree polynomial. (b) Conversely, show that every squarefree f ∈ k[x] gives rise to a hyperell...

In this dissertation, we study the following two topics, i.e., the union closed set conjecture and the maximum edges cut in connected digraphs. The union-closed-set-conjecture-topic goes as follows. A finite family of finite sets is union closed if it contains the union of any two sets in it. Let XF = ∪F∈FF . A union closed family of sets is separating if for any two distinct elements in F , th...

A. For f , g ∈ ω let c∀f ,g be the minimal number of uniform g-splitting trees needed to cover the uniform f -splitting tree, i.e., for every branch ν of the f -tree, one of the g-trees contains ν. Let c∃f ,g be the dual notion: For every branch ν, one of the g-trees guesses ν(m) infinitely often. We show that it is consistent that c∃fǫ ,gǫ = c ∀ fǫ ,gǫ = κǫ for continuum many pairwise d...

‎let us consider the set of non-abelian finite simple groups which‎ ‎admit non-trivial irreducible projective representations of degree $le 7$ over‎ ‎an algebraically closed field $f$ of characteristic $pgeq 0$‎. ‎we survey some recent results which‎ ‎lead to the complete list of the groups in this set which are‎ ‎$(2‎, ‎3‎, ‎7)$-generated and of those which are $(2,3)$-generated‎.

‎let us consider the set of non-abelian finite simple groups which‎ ‎admit non-trivial irreducible projective representations of degree $le 7$ over‎ ‎an algebraically closed field $mathbb{f}$ of characteristic $pgeq 0$‎. ‎we survey some recent results which‎ ‎lead to the complete list of the groups in this set which are‎ ‎$(2,3,7)$-generated and of those which are $(2,3)$-generated‎.

Let f be a diffeomorphism of a closed C∞ three-dimensional manifold. In this paper, we introduce the notion of C1-stably weak shadowing for a closed f -invariant set, and prove that C1-generically, for an aperiodic chain component Cf of f isolated in the chain recurrent set, if f|Cf is C 1-stably weak shadowing, then there are a C1-neighborhood U(f) of f and an open and dense subset V of U(f) s...

Background. Synthesizing complex materials can accelerate the development of technologies related to our daily life. A key bottleneck in synthesizing such materials is the large searching space of input features (such as temperature, pressure, reaction time, etc.) that needs to be explored under a limited experimental budget. Since there is not much historic data available, the success of class...

To demonstrate more visibly the close relation between thecontinuity and integrability, a new proof for the Banach-Zareckitheorem is presented on the basis of the Radon-Nikodym theoremwhich emphasizes on measure-type properties of the Lebesgueintegral. The Banach-Zarecki theorem says that a real-valuedfunction $F$ is absolutely continuous on a finite closed intervalif and only if it is continuo...