Jachymski [ Proc. Amer. Math. Soc., 136 (2008), 1359-1373] gave modified version of a Banach fixed point theorem on a metric space endowed with a graph. In the present paper, (G, Φ)-graphic contractions have been de ned by using a comparison function and studied the existence of fixed points. Also, Hardy-Rogers G-contraction have been introduced and some fixed point theorems have been proved. S...

In 2011, Gabeleh and Akhar [3] introduced semi-cyclic-contraction and considered the existence and convergence results of best proximity points in Banach spaces. In this paper, the author introduces a cone semicyclic φ-contraction pair in cone metric spaces and considers best proximity points for the pair in cone metric spaces. His results generalize the corresponding results in [1–5]..

A new generalization of the Gray map is introduced. The new generalization Φ : Z 2 → Z k−1 n 2 is connected with the known generalized Gray map φ in the following way: if we take two dual linear Z2k -codes and construct binary codes from them using the generalizations φ and Φ of the Gray map, then the weight enumerators of the binary codes obtained will satisfy the MacWilliams identity. The cla...

The aim of this paper is to prove the existence and convergence theorems for cyclic contractions. We introduce a notion called proximally complete pair (A,B) on a metric space, which unify the earlier notions that are used to prove the existence of a best proximity point for a cyclic contraction. By observing geometrical properties on a Hilbert space, we introduce Pythagorean property and use t...

In this paper, we show that contraction operations preserve the homology of nD generalized maps, under some conditions. This result extends the similar one given for removal operations in [6]. Removal and contraction operations are used to propose an efficient algorithm that compute homology generators of nD generalized maps. Its principle consists in simplifying a generalized map as much as po...

Notes taken by Stuart White during the lectures and not proof read. Errors will abound. 1. Nuclearity: Approximation and perturbation Recall: Definition 1.1. A C∗-algebra. Definition 1.2. A cp map Theorem 1.3. Stinespring’s theorem. Every cp map is a compression of a ∗-homomorphism. Definition 1.4. φ : A → B cp has order zero if a ⊥ b =⇒ φ(a) ⊥ φ(b). 1 Theorem 1.5. (i) φ : A→ B has order zero i...

In present times, there has been a substantial endeavor to generalize the classical notion of iterated function system (IFS). We introduce new type non-linear contraction namely cyclic Meir-Keeler contraction, which is generalization famous Banach contraction. show existence and uniqueness fixed point for Using this result, we propose IFS in literature construction fractals. Furthermore, extend...

Meir and Keeler in 1 considered an extension of the classical Banach contraction theorem on a complete metric space. Kirk et al. in 2 extended the Banach contraction theorem for a class of mappings satisfying cyclical contractive conditions. Eldred and Veeramani in 3 introduced the following definition. Let A and B be nonempty subsets of a metric space X. A map T : A ∪ B → A ∪ B, is a cyclic co...