New Physics Formulated Without Explicit Time. Research by David Deutsch and Chiara Marletto

A Timeless Formulation of Physics

David Deutsch and Chiara Marletto have presented a new theoretical framework that seeks to describe the laws of nature without an explicit time parameter. Using constructor theory, they recast physical laws in terms of which transformations of systems are possible or impossible, rather than how quantities evolve with time.

From Time‑Dependent to Task‑Based Laws

Traditional physics treats time as a background variable that orders events. The authors argue that this treatment is problematic when trying to reconcile quantum mechanics with general relativity. In their approach, a substrate—the physical system under study—is isolated if the feasibility of any task performed on it depends only on its own attributes, not on any external temporal reference. By defining isolation and reliability in terms of accuracy (distance between desired and actual output) and reliability (repeatability of that accuracy), the framework provides a concrete way to assess which tasks a constructor can perform.

Timers, Clocks, and Emergent Duration

A key innovation is the introduction of timers—special constructors that encode duration through their internal states rather than an external clock. A timer’s “halt flag” marks the completion of a task, and equivalence classes of timers share a common duration label. In this picture, the familiar ticking of a clock emerges from a series of possible transformations, not from a pre‑existing time flow.

Relation to Existing Timeless Approaches

The paper situates itself among earlier “timeless” proposals (Wheeler, DeWitt, Page & Wootters, Rovelli) but differs by providing an explanatory foundation: properties such as the existence of good clocks and locality are derived as consequences of deeper, task‑based constraints rather than taken as axioms. The authors also discuss superinformation media, a generalized quantum substrate that may impose additional constraints on admissible laws.

Why It Matters

If successful, this formulation could reshape how we think about dynamics, causality, and the unification of quantum theory with gravity. By focusing on what can happen rather than how things change over time, the theory offers a fresh lens for probing foundational questions about the nature of reality.

Open Questions and Next Steps

The framework is still at a conceptual stage. Key challenges include:

• Demonstrating concrete models that recover known physics from the timeless postulates.
• Identifying experimental signatures that could distinguish this approach from conventional formulations.
• Extending the theory to incorporate interactions with gravity in a fully consistent way.

Future work will need to translate these abstract task‑based principles into testable predictions, perhaps by designing experiments that probe the limits of possible vs. impossible transformations in quantum systems.

--- The ideas outlined here are drawn from the authors’ June 2026 manuscript and represent a significant conceptual advance, though peer‑reviewed validation is still pending.