3,146 research outputs found
Classicality of a quantum oscillator
Gaussian quantum systems exhibit many explicitly quantum effects but can be
simulated classically. Using both the Hilbert space (Koopman) and the
phase-space (Moyal) formalisms we investigate how robust this classicality is.
We find failures of consistency of the dynamics of a hybrid classical-quantum
systems from both perspectives. By demanding that no unobservable operators
couple to the quantum sector in the Koopmanian formalism, we show that the
classical equations of motion act on their quantum counterparts without
experiencing any back-reaction, resulting in non-conservation of energy in the
quantum system. Using the phase-space formalism we study the short time
evolution of the moment equations of a hybrid classical-Gaussian quantum system
and observe violations of the Heisenberg Uncertainty Relation in the quantum
sector for a broad range of initial conditions. We estimate the time scale for
these violations, which is generically rather short. This inconsistency
indicates that while many explicitly quantum effects can be represented
classically, quantum aspects of the system cannot be fully masked. We comment
on the implications of our results for quantum gravity
Determinism, independence and objectivity are incompatible
Hidden-variable models aim to reproduce the results of quantum theory and to
satisfy our classical intuition. Their refutation is usually based on deriving
predictions that are different from those of quantum mechanics. Here instead we
study the mutual compatibility of apparently reasonable classical assumptions.
We analyze a version of the delayed-choice experiment which ostensibly combines
determinism, independence of hidden variables on the conducted experiments, and
wave-particle objectivity (the assertion that quantum systems are, at any
moment, either particles or waves, but not both). These three ideas are
incompatible with any theory, not only with quantum mechanics.Comment: 4 pages, published versio
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Chilean Clitic Reduplication: Implications for Morphology and Syntax
This paper explores the phenomenon of clitic duplication in Spanish as seen in the sentence Te voy a pegarte (‘I’m going to hit you’). Structures like these have several interesting implications for the Spanish language and generativist syntax. Nevertheless, clitic duplication has not been extensively examined in the generativist literature. This working paper will critically review the small body of existing work on clitic reduplication. Furthermore, based on data gathered from native speakers of Chilean Spanish, it will provide some preliminary evidence for strengthening the argument that Spanish clitics are object agreement morphemes. Ultimately, this paper aims to provide a base to further pursue the topic of Chilean clitic reduplication to make more theoretically sound claims, provide more robust empirical data, and to propose a more formalized argument of the phenomena. Pedagogical implications of the argument are also considered
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