Stunning new observations and theories deepen the concept of causation. Quantum theory is one of the most striking discovery of contemporary physics, and it challenges many facets of older theories, even though it lies on many assumptions that could not be empirically experimented. In this paper, I will recall the views of Hume, Reichenbach and Einstein about the issue of causation, whereas I will focus on causal priority and temporal priority criteria in causation. Nevertheless, one task that I perform is the interpretation of these ideas by arguing them within the quantum scope. That is, trying to manifest Hume, Reichenbach and Einstein views of causation that I think as close, but I shall avoid putting straight cuts on where they differ. Direction of causal processes is dependent on the direction of time in Hume’s sense while Reichenbach explained the direction of time with irreversible processes, even if he follows the temporal priority criteria of Hume. It is stated that there is nothing faster than light by Einstein, as a result, a cause could not pass the upper limit of light. Crudely put, their thoughts all differ from the principles of quantum, because causation (causation might denote a different meaning in quantum realm) may be able to travel faster than light and the common cause principle between events is rejected in quantum realm.
Stunning new observations and theories deepen the concept of causation. Quantum theory is one of the most striking discovery of contemporary physics, and it challenges many facets of older theories, even though it lies on many assumptions that could not be empirically experimented. In this paper, I will recall the views of Hume, Reichenbach and Einstein about the issue of causation, whereas I will focus on causal priority and temporal priority criteria in causation. Nevertheless, one task that I perform is the interpretation of these ideas by arguing them within the quantum scope. That is, trying to manifest Hume, Reichenbach and Einstein views of causation that I think as close, but I shall avoid putting straight cuts on where they differ. Direction of causal processes is dependent on the direction of time in Hume’s sense while Reichenbach explained the direction of time with irreversible processes, even if he follows the temporal priority criteria of Hume. It is stated that there is nothing faster than light by Einstein, as a result, a cause could not pass the upper limit of light. Crudely put, their thoughts all differ from the principles of quantum, because causation (causation might denote a different meaning in quantum realm) may be able to travel faster than light and the common cause principle between events is rejected in quantum realm.
I have claimed that it is profitable to distinguish three key questions about causation. The first question, what are causal processes and interactions? , was addressed in Chapter 5. The second question, what is the connection between causes and effects? , was addressed in Chapter 7.The third question, what makes a cause different from an effect? , has not been addressed, and it is to that task that we turn in the present chapter. The question of the directionality and asymmetry of causation has long been an important ingredient in philosophical discussions of causation, although perhaps Reichenbach (1991) was the first to truly appreciate the significance of the question. It is certainly an aspect of folk intuitions. Many philosophers have held that an adequate analysis of causality should provide an explanation or account of causal asymmetry. On the other hand, it is precisely this aspect of causation that is the most common target for elimination from empirical accounts. This chapter looks at the ability of 'process' theories of causality to provide such an account, granting certain constraints. The major constraint, or premise, in the following analysis is the assumption that quantum mechanics reveals the presence of backwards-in-time causation. Thus, in the first instance, the argument presented here will not convince those who hold that there can be no backwards causation. However, I derive an empirical prediction, which, if confirmed, would give those sceptical about backwards causation reason to think again. The chapter begins with an analysis of some of the formal properties of causation. This is followed by a nontechnical presentation of the famous difficulties associated with Bell phenomena in quantum mechanics, and the backwards-in-time solution to those difficulties.
Philosophical analyses of causation take many forms but one major difficulty they all aim to address is that of the spatiotemporal continuity between causes and their effects. Bertrand Russell in 1913 brought the problem to its most transparent form and made it a case against the notion of causation in physics. The issue highlighted in Russell's argument is that of temporal contiguity between cause and effect. This tension arises from the imposition of a spectrum of discrete events occupying spacetime points upon a background of spacetime continuum. An immediate and natural solution is to superpose instead spatiotemporally continuous entities, or processes, on the spacetime continuum. This is indeed the process view of physical causation advocated by Wesley Salmon and Phil Dowe. This view takes the continuous trajectories of physical objects (worldlines) as the causal connection whereby causal influences in the form of conserved quantities are transported amongst events. Because of their reliance on spatiotemporal continuity, these theories have difficulty when confronted with the discontinuous processes in the quantum domain. This thesis is concerned with process theories. It has two parts. The first part introduces and criticizes these theories, which leads to my proposal of the History Conserved Quantity Theory with Transmission. The second part considers the extension of the idea of causal processes to quantum physics. I show how a probability distribution generated by the Schrodinger wavefunction can be regarded as a conserved quantity that makes the spacetime evolution of the wavefunction a quantum causal process. However, there are conceptual problems in the interpretation of the wavefunction, chiefly to do, as I shall argue, with the difference in the behaviours of probabilistic potentials between quantum and classical physics. I propose in the final chapter, the Feynman Path Integral formulation of quantum mechanics (with the Feynman histories) as an alternative approach to incorporating the probabilistic potentials in quantum physics. This account of how to introduce causal processes in quantum mechanics fares better, I claim, than the previous one in dealing with the situational aspect of quantum phenomena that requires the consideration of events at more than one time.
Abstract There is widespread agreement that quantum mechanics has something radical to teach us about causation. But opinions differ on what this is. Physicists have often taken the central lesson to be that many physical events occur spontaneously, so that a principle of causality is violated whenever an atom emits light, or a uranium nucleus decays, even though nothing that happened beforehand made this inevitable. Feynman urged philosophers to acknowledge that this implication of quantum mechanics undermines the view that causal determinism forms a precondition of scientific inquiry. But while some physicists have denied the implication, most philosophers since Reichenbach have accepted it with alacrity, and sought to develop accounts of causation equally applicable in an indeterministic or a deterministic world.
Introduction Important advances in scientific knowledge may, not infrequently, be looked at from several angles. Here, in investigating the question the article title defines, part of our attention will have to be turned on the relationships of Bell's theorem to the old, but still not fully cleared up, question of the nature of causality. The word “nonlocality” means the violation of local causality, the initial meaning of whichwas that no influence, that is, no causal action , can be propagated faster than light. For a long time it was a received view that actions somewhat akin to the basically time-directed ones that living beings perform also take place within inanimate nature. This conception of causality may be called the causality–action theory . But later, having in view Hume's serious reservations concerning it, renowned philosophers of science claimed it might and should be dropped, since the effects it was meant to account for could be explained just as well by considering that what is at work is simply a conjunction of physical laws expressed by means of differential equations – a view that later Hempel and Oppenheim generalized and called the D-N (deductive–nomological) model of explanation (reprinted in [1]). Here the (widely accepted, as it seems) corresponding conception of causality will, for simplicity, be called the law-centered theory of causality . But does the latter theory subsume, at least within physics, all the meanings of the word ‘cause’ that true understanding calls for? Among philosophers the matter is not settled. Hempel himself granted that in several respects the D-N model is somehow inadequate for analyzing the cause–effect relationship [2]. And it seems indeed that a significant argument favoring a ‘no’ answer to the question might have been put forward as early as 1907 (although, to our knowledge, it was not), when Einstein pointed out that according to his then two years old special relativity (SR) theory, if we assumed an effect could follow its cause sooner than light velocity permits, then in some other frames of reference it would occur before its cause. For, concerning this consequence of the assumption, he wrote, “in my opinion, regarded as pure logic … it contains no contradiction; however it absolutely clashes with the character of our total experience, and in this way is proved the impossibility of the hypothesis” [3].
Reichenbach's Common Cause Principle is the claim that if two events are correlated, then either there is a causal connection between the correlated events that is responsible for the correlation or there is a third event, a so called (Reichenbachian) common cause, which brings about the correlation. The paper reviews some results concerning Reichenbach's notion of common cause, results that are directly relevant to the problem of how one can falsifY Reichenbach's Common Cause Principle. Special emphasis will be put on the question of whether EPR-type correlations can have an explanation in terms of Reichenbachian common causes. Most of the results to be recalled indicate that falsifYing Reichenbach's Common Cause Principle is much more tricky than one may have thought and that, contrary to some claims in the literature, there is no conclusive proof yet that the EPR correlations predicted by ordinary, non-relativistic quantum mechanics cannot have a common cause; furthermore, recent results about possible Reichenbachian common causes of correlations predicted by quantum field states between spacelike separated local observable algebras in algebraic quantum field theory strongly indicate that there may very well exist Reichenbachian common causes of superluminal correlations predicted by quantum field theory.
This Ph.D. thesis is about causality in Quantum Mechanics, namely about the possibility to provide a causal explanation for quantum Einstein – Podolsky – Rosen (EPR) correlations.The well-known interpretation of the Bell’s Theorem by Bastian Van Fraassen, who inferred that quantum correlations cannot be embedded in any causal model, compels us to suppose that microscopic nature cannot have a causal structure and that causality is an anthropological concept.However, this interpretation is not commonly accepted and this doctoral thesis is the first general overview of some recent works about causal explanation for EPR correlations. Particularly, it analyses the possible causal explanations for the EPR/Bohm experiments by means of the Hans Reichenbach’s model, by means of backward causation models, and by means of models that imply a direct causal link. In order to do it, it pays particular attention to the Relativistic space-time features and it considers the studies in the History of Philosophy about the link between causal arrow and temporal arrow. Moreover, this work aims to endorse the idea that the best way to explain EPR/Bohm correlations causally is to adopt an indeterministic non-Reichenbachian common cause model, particularly Cartwright’sgeneral forksmodel.My conclusion is that causal models for quantum correlations remain viable, and that there is no contrast between genuinely indeterministic interpretation of Quantum Theory and causal explanation, with the philosophical implication that the Causal Realism is still acceptable.