This paper explores an event-based version of quantum mechanics which differs from the commonly accepted one, even though the usual elements of quantum formalism, e.g., the Hilbert space, are maintained. This version introduces as primary element the occurrence of micro-events induced by usual physical (mechanical, electromagnetic and so on) interactions. These micro-events correspond to state reductions and are identified with quantum jumps, already introduced by Bohr in his atomic model and experimentally well established today. Macroscopic bodies are defined as clusters of jumps; the emergence of classicality thus becomes understandable and time honoured paradoxes can be solved. In particular, we discuss the cat paradox in this context. Quantum jumps are described as temporal localizations of physical quantities; if the information associated with these localizations has to be finite, two time scales spontaneously appear: an upper cosmological scale and a lower scale of elementary “particles”. This allows the interpretation of the Bekenstein limit like a particular informational constraint on the manifestation of a micro-event in the cosmos it belongs. The topic appears relevant in relation to recent discussions on possible spatiotemporal constraints on quantum computing.

According to the usual quantum description, the time evolution of the quantum state is continuous and deterministic except when a discontinuous and indeterministic collapse of state vector occurs. The collapse has been a central topic since the origin of the theory, although there are remarkable theoretical proposals to understand its nature, such as the Ghirardi–Rimini–Weber. Another possibility could be the assimilation of collapse with the now experimentally well established phenomenon of quantum jump, postulated by Bohr already in 1913. The challenge of nonlocality offers an opportunity to reconsider the quantum jump as a fundamental element of the logic of the physical world, rather than a subsidiary accident. We propose here a simple preliminary model that considers quantum jumps as processes of entry to and exit from the usual temporal domain to a timeless vacuum, without contradicting the quantum relativistic formalism, and we present some potential connections with particle physics. Quanta 2015; 4: 10–26.

Some ideas are explored concerning the structure of elementary particles (specifically, leptons and hadrons), formulated within the context of a theory of the objective collapse of the wavefunction recently proposed by the authors. In accordance with this hypothesis, to each interaction that induces a discontinuity (quantum jump) in the evolution of the state of an elementary particle, two de Sitter half-spaces are associated, respectively, connected with the outgoing state and its conjugate. It is in these spaces that the structural constituents of the particle lie (quarks in the case of a hadron). The mass of free particles (leptons and hadrons) is given by the energy associated with their time localization in the jump, while the interaction between quarks belonging to a same hadron leads to a chromodynamic coupling constant that ensures both confinement and asymptotic freedom. It is possible to write a toy Hamiltonian in which the organization of quarks in hadrons appears ab initio, and which includes terms both for the exchange of quarks and for the creation/annihilation of pairs, thus avoiding the problem of bottom-up hadronization. In this scenario, the genesis of Regge trajectories is briefly discussed and it is argued that their slope can be quantized; finally, a reinterpretation is suggested of the classical Veneziano and Virasoro amplitudes.

In this article a completely objective decoherence mechanism is hypothesized, operating at the level of the elementary particles of matter. The standard quantum mechanical description is complemented with a phenomenological evolution equation, involving a scalar curvature and an internal time, distinct from the observable time of the laboratory. This equation admits solutions internal to the wave function collapse, and the classical instantons connected to these solutions represent de Sitter micro-spaces identifiable with elementary particles. This result is linked in a natural way to other research programs tending to describe the internal structure of elementary particles by means of de Sitter spaces. Both the possible implications in particle physics and those deriving from the conversion of quantum information (qubits) into classical information (bits) are highlighted.