Decoherence, macrorealism and the causal arrow of time: There is more than meets the eye

In an attempt to test the limits of the current interpretation of quantum mechanics, according to which microscopic systems are always in a superposition of states, A. Leggett has proposed the thesis of macrorealism, according to which quantum mechanical super positions of macroscopically distinct states never occur. Leggett has also shown the basic features of some experimental tests that would decide definitively between quantum mechanics and macrorealism. In this paper I develop an interpretation of macrorealism from which the experimental results can be understood as examples of violations of the principle of induction in which macrorealism rests, opening the door for solving the tension between QM and macrorealism in terms of the backwards causation. According to this interpretation there is no need for appealing to any special role played by either observers or measurement apparatuses in order to explain what differentiates quantum systems from macroscopic ones, a difference that could now be defined partly in terms of their causal and temporal directionality.