# (Sub)fit biframes and non-symmetric nearness

@article{Picado2014SubfitBA, title={(Sub)fit biframes and non-symmetric nearness}, author={J. Picado and A. Pultr}, journal={Topology and its Applications}, year={2014}, volume={168}, pages={66-81} }

Abstract The non-symmetric (quasi-)nearness and its generalized admissibility are studied both in its biframe and paircovers aspect and in the perspective of entourages. The necessary and sufficient condition for a biframe to carry such an enrichment is shown to be a biframe variant of subfitness (resp. fitness, in the hereditary case).

#### 8 Citations

PROXIMITY BIFRAMES AND COMPACTIFICATIONS OF COMPLETELY REGULAR ORDERED SPACES

- 2015

We generalize the concept of a strong inclusion on a biframe [Sch93] to that of a proximity on a biframe, which is related to the concept of a strong bi-inclusion on a frame introduced in [PP12b]. We… Expand

STILL MORE ABOUT SUBFITNESS JORGE PICADO AND

- 2014

Several features of subfitness are analyzed. Isbell’s Spatiality Theorem leads to the concept of T1-spatiality which is compared with the TD-spatiality. Subfitness is put into relation with other… Expand

New Aspects of Subfitness in Frames and Spaces

- Mathematics, Computer Science
- Appl. Categorical Struct.
- 2016

Another necessary and sufficient condition for subfitness presented is the validity of the meet formula for the Heyting operation, which was so far known only under much stronger conditions. Expand

On Isbell's density theorem for bitopological pointfree spaces I

- Mathematics
- 2020

Abstract This paper addresses dense sub-objects for point-free bitopology in terms of d-frames and provides several examples. We characterize extremal epimorphisms in d-frames and show that a… Expand

More on Subfitness and Fitness

- Mathematics, Computer Science
- Appl. Categorical Struct.
- 2015

Another property, prefitness, is shown to also produce fitness by heredity, in this case in a way usable for classical spaces, which results in a transparent characteristics of fit spaces, and the properties are proved to be independent. Expand

The assembly of a pointfree bispace and its two variations

- Mathematics
- 2020

The duality of finitary biframes as pointfree bitopological spaces is explored. In particular, for a finitary biframe $\mathcal{L}$ the ordered collection of all its pointfree bisubspaces (i.e. its… Expand

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