Continua which cannot be mapped onto any nonplaner circle-like continuum

نویسندگان

چکیده

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Exactly two-to-one maps from continua onto some tree-like continua

It is known that no dendrite (Gottschalk 1947) and no hereditarily indecomposable tree-like continuum (J. Heath 1991) can be the image of a continuum under an exactly 2-to-1 (continuous) map. This paper enlarges the class of tree-like continua satisfying this property, namely to include those tree-like continua whose nondegenerate proper subcontinua are arcs. This includes all Knaster continua ...

متن کامل

Mapping Chainable Continua onto Dendroids

We prove that every chainable continuum can be mapped into a dendroid such that all point-inverses consist of at most three points. In particular, it follows that there exists a finite-to-one map from a hereditarily indecomposable continuum (the pseudoarc) onto hereditarily decomposable continuum. This answers a question by J. Krasinkiewicz.

متن کامل

Hypersurface Singularities Which Cannot Be Resolved in Characteristic Positive

Assume that there exists a hypersurface singularity which cannot be resolved by iterated monoidal transformations in positive characteristic. We show that in the set of defining functions of hypersurface singularities which cannot be resolved, we can find a function satisfying very strong conditions. By these conditions we may be able to deduce a contradiction under the above assumption. Beside...

متن کامل

Vacuum Solutions Which Cannot Be Written in Diagonal Form *

The vacuum solution ds 2 = dx 2 + x 2 dy 2 + 2 dz dt + ln x dt 2 of the Einstein gravitational field equation follows from the general ansatz ds 2 = dx 2 + g αβ (x) dx α dx β but fails to follow from it if the symmetric matrix g αβ (x) is assumed to be in diagonal form.

متن کامل

A definable number which cannot be approximated algorithmically

The Turing machine (TM) and the Church thesis have formalized the concept of computable number, this allowed to display noncomputable numbers. This paper defines the concept of number “approachable” by a TM and shows that some (if not all) known non-computable numbers are approachable by TMs. Then an example of a number not approachable by a TM is given.

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Colloquium Mathematicum

سال: 1971

ISSN: 0010-1354,1730-6302

DOI: 10.4064/cm-23-2-241-243