Science & Tech · Science & Environment · 1 hr ago
Physicists are re-examining whether the past matters in quantum theory
Many familiar laws of physics predict what happens next using only the present state of a system.
This assumption is known as Markovianity, and it means a system’s past is treated as unnecessary for predicting its future.
In quantum theory, this approach also applies to particles that can exist in a mixture of states, like the imagined cat that is both alive and dead in Schrödinger’s thought experiment.
Some researchers now want physics to account for the past, rather than assuming the present tells the whole story.
They think this could help explain why quantum theory behaves as strangely as it does, while not being even stranger.
The debate could also shed light on the nature of time.
The account does not specify what researchers will do next or whether this approach has resolved any questions.
Physicists are reconsidering the assumption that the present alone is enough to predict the future.
The assumption, known as Markovianity, is widely used in physics, including standard quantum mechanics.
Proponents of taking the past into account say this could help address long-standing questions in quantum theory and clarify the nature of time.
Quantum information researcher Jacob Biamonte called the effort important for the foundations of physics.
- Who
- Physicists reconsidering the role of the past in quantum theory, including quantum information researcher Jacob Biamonte.
- What
- They are challenging the assumption that the present alone is enough to predict the future.
- When
- The article was published on 9 November 2026.
- Where
- Not stated
- Why
- Proponents think considering the past could help resolve long-standing questions in quantum theory and clarify the nature of time.
Proponents of reclaiming the past for physics
Supporters of Markovianity
Role of the past
Proponents of reclaiming the past for physics
The past may matter for predicting the future and could help address questions in quantum theory.
Supporters of Markovianity
The present is treated as sufficient to predict the future.
Use in physics
Proponents of reclaiming the past for physics
Proponents want to reconsider the assumption that the past can be neglected.
Supporters of Markovianity
Markovianity is widely used in physics, including standard quantum mechanics.
This story does not have a timeline yet.
- Publication date
- 9 November 2026
- Named principle
- Markovianity
- Researcher
- Jacob Biamonte
- Institution
- École de Technologie Supérieure, Montreal
- Example thought experiment
- Schrödinger’s cat in a superposition of being alive and dead
What people are saying
I think it’s a big deal. I think it will be a big thing for the foundations of physics