Let k be a non-archimedean field: a field that is complete with respect to a specified nontrivial non-archimedean absolute value | · |. There is a classical theory of k-analytic manifolds (often used in the theory of algebraic groups with k a local field), and it rests upon versions of the inverse and implicit function theorems that can be proved for convergent power series over k by adapting t...

In this paper, we prove the generalized Hyres–Ulam–Rassias stability of the mixed type cubic and quartic functional equation f (x + 2y) + f (x − 2y) = 4(f (x + y) + f (x − y)) − 24f (y) − 6f (x) + 3f (2y) in non-Archimedean ℓ-fuzzy normed spaces.

We show an example of a non-archimedean version of the existence part of the Calabi-Yau theorem in complex geometry. Precisely, we study totally degenerate abelian varieties and certain probability measures on their associated analytic spaces in the sense of Berkovich.

In this paper, we prove the stability of the functional equation ∑ 1 i, j n,i = j ( f (xi + x j)+ f (xi − x j) ) = (n−1) n ∑ i=1 ( 3 f (xi)+ f (−xi) ) in non-Archimedean normed spaces. Mathematics subject classification (2010): 39B82, 46S10, 39B52.

In this paper, we prove the generalized Hyers–Ulam stability of the following additive-quadratic-cubic-quartic functional equation f(x + 2y) + f(x− 2y) = 4f(x + y) + 4f(x− y)− 6f(x) + f(2y) + f(−2y)− 4f(y)− 4f(−y) in non-Archimedean Banach spaces.

In this paper, we investigate the generalized Hyers–Ulam stability for the functional equation f(ax+y)+af(y−x)− a(a+ 1) 2 f(x)− a(a+ 1) 2 f(−x)− (a+1)f(y) = 0 in non-Archimedean normed spaces. Mathematics Subject Classification: 39B52, 39B82

Jointly with H.-P. Künzi we started investigating a concept of spherical completeness in ultra-quasipseudometric spaces which we called q-spherical completeness. In this article we study fixed point theorems in a space X endowed with a non-Archimedean asymmetric norm structure. Here we extend certain results of Petalas and Vidalis and Kirk and Shahzad.

In this paper, we obtain the general solution and investigate the Hyers-Ulam-Rassias stability of the functional equation f(ax− y)± af(x± y) = (a± 1)[af(x)± f(y)] in non-Archimedean -fuzzy normed spaces. Mathematics Subject Classification: 39B55, 39B52, 39B82

and Applied Analysis 3 The functional equation 1.7 was first solved by Kannappan. In fact he proved that a mapping f on a real vector space is a solution of 1.7 if and only if there exists a symmetric biadditive mapping B and an additive mapping A such that f x B x, x A x , for any x see 9 . The stability problem for 1.7 is also studied in 26 . Moreover 1.7 was pexiderized and solved by Kannapp...