Branching Space-times Research Articles

The Topology of Branching Universes

The purpose of this paper is to survey the possible topologies of branching space-times, and, in particular, to refute the popular notion in the literature that a branching space-time requires a non-Hausdorff topology.

A Theory of Causation: Causae Causantes (Originating Causes) as Inus Conditions in Branching Space-Times

Branching space-times (BST) theory, as developed elsewhere, permits a sound and rigorously definable notion of ``originating cause'' or causa causans---a type of transition event---of an outcome event. Mackie has famously suggested that causes form a family of ``inus'' conditions, where an inus condition is ``an insufficient but non-redundant part of an unnecessary sufficient condition.'' In this essay the needed concepts of BST theory are developed in detail, and it is then proved that the causae causantes a given outcome event have exactly the structure of a set of Mackie inus conditions. The proof requires the assumption that there is no EPR-like ``funny business.'' This seems enough to constitute a theory of ``causation'' in at least one of its many senses.

Quantum state holism: a case for holistic causation

I propose to interpret quantum state holism as a view concerning possibilities: the degree of possibility of a compound's outcome is not determined by the degrees of possibility of the components' outcomes. To analyze this proposal I sketch the modal framework of branching space-times with probabilities understood as weights of possibility. These probabilities serve to define holistic events. A holistic event produces its outcomes subluminally; yet the degree of possibility of its outcome is not determined by the degrees of possibility imposed by the event's components.

No-common-cause EPR-like funny business in branching space-times

There is "no EPR-like funny business" if (contrary to apparent fact) our world is as indeterministic as you wish, but is free from the EPR-like quantum-mechanical phenomena such as is sometimes described in terms of superluminal causation or correlation between distant events. The theory of branching space-times can be used to sharpen the theoretical dichotomy between "EPR-like funny business" and "no EPR-like funny business." Archived publication PITT-PHIL-SCI00000451 offered two analyses of the dichotomy, and proved them equivalent. This essay adds two more, both connected with Reichenbach's "principle of the common cause," the principle that sends us hunting for a common-cause explanation of distant correlations. The two previous ideas of funny business and the two ideas introduced in this essay are proved to be all equivalent, which increases one's confidence in the stability of (and helpfulness of) the BST analysis of the dichotomy between EPR-like funny business and its absence.