Patrick Jaubert

Two primitives for time: Relational time (Page–Wootters) and process time (actualization)

In canonical quantum gravity, the Hamiltonian constraint Ĥ|Ψ⟩ = 0 deprives the universe of any explicit temporal evolution: this is the "problem of time". The Page–Wootters (PaW) mechanism answers it by reconstructing a relational time: from a stationary global state, the evoluti...

What a universe that becomes changes: The foundational reach of Time-Actualization beyond hard physics

Time–Actualization (TA) is a foundational interpretation empirically equivalent to quantum mechanics on a causal-set substrate: it makes no new prediction (a constraint of admissibility, adopted with QM, we label P5). It therefore has, by construction, no purchase in hard physics...

An ontology for causal-set dynamics: Becoming as actualization, the basis as causal past

The causal-set programme proposes that spacetime is, at bottom, a discrete poset whose Lorentzian geometry emerges, endowed with a covariant sequential growth dynamics. It leaves open, however, two points that an ontology must settle: the status of the "becoming" of growth (a com...

The preferred basis is causal: The measurement problem in an ontology of actualization

The "preferred-basis problem" — why does measurement produce definite outcomes in this basis rather than another — is treated in opposite ways by the interpretations of quantum mechanics: posited ab initio (spontaneous collapse), drawn from a contingent environment (decoherence),...

Two primitives for time: Relational time (Page–Wootters) and process time (actualization)

In canonical quantum gravity, the Hamiltonian constraint Ĥ|Ψ⟩ = 0 deprives the universe of any explicit temporal evolution: this is the "problem of time". The Page–Wootters (PaW) mechanism answers it by reconstructing a relational time: from a stationary global state, the evoluti...

What a universe that becomes changes: The foundational reach of Time-Actualization beyond hard physics

Time–Actualization (TA) is a foundational interpretation empirically equivalent to quantum mechanics on a causal-set substrate: it makes no new prediction (a constraint of admissibility, adopted with QM, we label P5). It therefore has, by construction, no purchase in hard physics...

The preferred basis is causal: The measurement problem in an ontology of actualization

The "preferred-basis problem" — why does measurement produce definite outcomes in this basis rather than another — is treated in opposite ways by the interpretations of quantum mechanics: posited ab initio (spontaneous collapse), drawn from a contingent environment (decoherence),...

Time as Actualization: A foundational ontology reconciling the quantum future and the relativistic past

Quantum mechanics describes the potential future; general relativity describes the actualized past; the present is the process of actualization that turns the one into the other. That single move is Time–Actualization (TA), the foundational ontology set out here. TA assumes the q...