Pasch's axiom and projective spaces
نویسندگان
چکیده
منابع مشابه
THE URYSOHN AXIOM AND THE COMPLETELY HAUSDORFF AXIOM IN L-TOPOLOGICAL SPACES
In this paper, the Urysohn and completely Hausdorff axioms in general topology are generalized to L-topological spaces so as to be compatible with pointwise metrics. Some properties and characterizations are also derived
متن کاملProjective embedding of projective spaces
In this paper, embeddings φ : M → P from a linear space (M,M) in a projective space (P,L) are studied. We give examples for dimM > dimP and show under which conditions equality holds. More precisely, we introduce properties (G) (for a line L ∈ L and for a plane E ⊂ M it holds that |L ∩ φ(M)| 6 = 1) and (E) (φ(E) = φ(E) ∩ φ(M), whereby φ(E) denotes the by φ(E) generated subspace of P ). If (G) a...
متن کاملAffine Spaces within Projective Spaces
We endow the set of complements of a fixed subspace of a projective space with the structure of an affine space, and show that certain lines of such an affine space are affine reguli or cones over affine reguli. Moreover, we apply our concepts to the problem of describing dual spreads. We do not assume that the projective space is finitedimensional or pappian. Mathematics Subject Classification...
متن کاملMetric spaces and the axiom of choice
We shall start with some definitions from topology. First of all, a metric space is a topological space whose topology is determined by a metric. A metric on a topological space X is a function d from X × X to R , the reals, which has the following properties: For all x, y, z ∈ X , (a) d(x, y) ≥ 0, (b) d(x, x) = 0, (c) if d(x, y) = 0, then x = y, (d) d(x, y) = d(y, x), and (e) d(x, y) + d(y, z)...
متن کاملذخیره 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: Discrete Mathematics
سال: 1981
ISSN: 0012-365X
DOI: 10.1016/0012-365x(81)90260-0