Science & Tech · Science & Environment · 2 hrs ago
Researchers use past and future readings to improve quantum measurements
Researchers led by a team from Shanxi University in China tested a new way to measure quantum properties.
They used information gathered both before and after a point in time to estimate a system’s position and momentum, which are normally difficult to measure precisely together.
The experiment used 52 billion rubidium atoms whose spins were aligned with a laser.
The team says its estimates were about 20 percent more precise than the usual Heisenberg bound allows, but this does not overturn the uncertainty principle, which still applies to quantum systems.
Using later readings means the method is less suited to real-time monitoring, though it could help improve quantum sensors and may fit systems that already use retrospective readings.
The researchers plan to refine their equipment and explore whether quantum entanglement could improve the method; their paper has not yet been peer-reviewed.
Researchers led by a team from Shanxi University in China report a way to improve simultaneous measurements of two quantum properties.
They used readings taken both before and after a measurement to estimate a system’s state.
In an experiment with rubidium atoms, the approach measured position and momentum simultaneously.
The researchers say their estimates were about 20 percent more precise than the Heisenberg uncertainty bound allows.
Their paper is a preprint and has not yet been peer-reviewed.
- Who
- Researchers led by a team from Shanxi University in China.
- What
- They used readings from before and after a measurement to improve simultaneous estimates of position and momentum.
- When
- The paper was published as a preprint on November 12, 2026.
- Where
- The researchers are from Shanxi University in China. The experiment used rubidium atoms in a small glass chamber.
- Why
- To improve the accuracy of quantum measurements and explore applications in quantum-enhanced sensing.
This story does not have two clearly opposing sides.
German physicist Werner Heisenberg introduced the uncertainty principle.
Researchers tested the approach using rubidium atoms and measurements taken before and after the point being measured.
ScienceAlert reported on the researchers’ preprint, which had not yet been peer-reviewed.
- Researchers
- Team led by Shanxi University researchers in China
- Atoms
- 52 billion rubidium atoms
- Measurement duration
- 84 minutes
- Accuracy
- Around 20 percent more precise than the Heisenberg uncertainty limit allows
- Paper status
- Preprint; not yet peer-reviewed
What people are saying
We experimentally demonstrate simultaneous estimation of non-commuting variables beyond the Heisenberg uncertainty bound and verify the results using weak measurement
The central ingredient of this approach is the consistent incorporation of both past and future measurement information to refine the inference of the system state at a given time
This brings interesting prospects for further research on quantum measurements, and for quantum-enhanced sensing that combines trajectory and entanglement strategies