Observation Space And Observables In Classical Mechanics
Observation space and observables in classical mechanics.
On measure for projectors
An example of a finite set of projectors in is exhibited for which no 0-1 measure exists.
On a functional representation of the lattice of projections on a Hilbert space
On a problem of Sikorski in the set representability of Boolean algebras
On a proof of the Erdős-Monk theorem.
On A Random Function Defined On A Pseudo Boolean Algebra
On a sufficient condition for strong constructivizability of atomic Boolean algebras.
On a theorem of Baumgartner and Weese
On a weak Freudenthal spectral theorem
Let be an Archimedean Riesz space and its Boolean algebra of all band projections, and put and , . is said to have Weak Freudenthal Property () provided that for every the lattice is order dense in the principal band . This notion is compared with strong and weak forms of Freudenthal spectral theorem in Archimedean Riesz spaces, studied by Veksler and Lavrič, respectively. is equivalent to -denseness of in for every , and every Riesz space with sufficiently many projections...
On absolute retracts of ω*
An extremally disconnected space is called an absolute retract in the class of all extremally disconnected spaces if it is a retract of any extremally disconnected compact space in which it can be embedded. The Gleason spaces over dyadic spaces have this property. The main result of this paper says that if a space X of π-weight is an absolute retract in the class of all extremally disconnected compact spaces and X is homogeneous with respect to π-weight (i.e. all non-empty open sets have the same...
On absolutely divergent series
We show that in the -stage countable support iteration of Mathias forcing over a model of CH the complete Boolean algebra generated by absolutely divergent series under eventual dominance is not isomorphic to the completion of P(ω)/fin. This complements Vojtáš’ result that under the two algebras are isomorphic [15].
On automorphism groups of boolean algebras
On automorphism groups of non-associative Boolean rings.
On automorphisms of Boolean algebras embedded in P (ω)/fin
We prove that, under CH, for each Boolean algebra A of cardinality at most the continuum there is an embedding of A into P(ω)/fin such that each automorphism of A can be extended to an automorphism of P(ω)/fin. We also describe a model of ZFC + MA(σ-linked) in which the continuum is arbitrarily large and the above assertion holds true.
On Boolean modus ponens.
An abstract form of modus ponens in a Boolean algebra was suggested in [1]. In this paper we use the general theory of Boolean equations (see e.g. [2]) to obtain a further generalization. For a similar research on Boolean deduction theorems see [3].
On Boolean partial differential equations
On BPI Restricted to Boolean Algebras of Size Continuum
(i) The statement P(ω) = “every partition of ℝ has size ≤ |ℝ|” is equivalent to the proposition R(ω) = “for every subspace Y of the Tychonoff product the restriction |Y = Y ∩ B: B ∈ of the standard clopen base of to Y has size ≤ |(ω)|”. (ii) In ZF, P(ω) does not imply “every partition of (ω) has a choice set”. (iii) Under P(ω) the following two statements are equivalent: (a) For every Boolean algebra of size ≤ |ℝ| every filter can be extended to an ultrafilter. (b) Every Boolean algebra of...
On Carathéodory vector lattices
On CCC boolean algebras and partial orders
We partially strengthen a result of Shelah from [Sh] by proving that if and is a CCC partial order with e.g. (the successor of ) and then is -linked.