Los Alamos National Laboratory Designs Protocols to Manipulate Quantum Arrow of Time
Summarize this article with:
Los Alamos National Laboratory researchers have designed quantum control protocols capable of manipulating the fundamental “arrow of time” within quantum systems, effectively making quantum processes appear to flow backward. Published in Physical Review X, the work details techniques to control qubits and other quantum systems, thereby altering their perception of time’s direction and opening possibilities for novel energy-extraction methods. Unlike classical physics, where measurements have limited impact, these quantum protocols leverage measurements and feedback to engineer time-reversed trajectories, influencing a system’s state in ways that challenge conventional understandings of entropy. “At the microscopic level most fundamental laws of physics see forward and backward movement in time as physically possible,” said Los Alamos National Laboratory physicist Luis Pedro García-Pintos; the team’s control Hamiltonian allows them to cancel, amplify, or even invert measurement disturbances, creating a quantum “demon” capable of reversing the natural order within a system.
Quantum Control Protocols Reverse System’s “Arrow of Time” Quantum control protocols have demonstrated the ability to manipulate the fundamental direction of time within a closed quantum system. Research published in Physical Review X details how scientists engineered techniques to control quantum systems, effectively altering what is known as the “arrow of time,” the unidirectional flow from past to future. This isn’t time travel in the conventional sense, but a manipulation of the quantum realm where the laws of physics don’t inherently dictate a single temporal direction; instead, the team has shown the ability to create processes that appear to unfold in reverse. The implications extend to potential energy harvesting from quantum systems and novel methods for preparing quantum states.
The team at Los Alamos National Laboratory achieved this by leveraging measurements and feedback loops to engineer “time-reversed stochastic trajectories,” causing the quantum system to behave as if time were flowing backward. This approach allows for the creation of a measurement engine capable of extracting energy from the quantum measurements themselves, effectively turning observation into a thermodynamic resource that could power other processes or be stored in a quantum battery; next steps involve demonstrating these processes with superconducting qubits, a platform suited for rapid feedback and high detection efficiencies. They designed a “control Hamiltonian,” a carefully sequenced series of fields and pulses, to mimic the effects of measurements, then used this in a feedback process to counteract or amplify measurement disturbances. “In other words, the laws of physics are symmetrical under time reversal; the equations work just as well if you reverse time.” This work draws parallels to the 19th-century thought experiment of “Maxwell’s demon,” which proposed decreasing entropy through manipulation of particles, seemingly violating the laws of thermodynamics.
The Los Alamos team’s quantum “demon” similarly exploits knowledge of the system’s state to drive anomalous processes, reversing the arrow of time.
Hamiltonian Measurement Drives Energy Extraction from Qubits This manipulation isn’t merely academic, as the scientists have demonstrated its application in designing a measurement engine that actively extracts energy from the quantum measurement process. This energy extraction stems from a unique application of Hamiltonian measurement, where a carefully crafted sequence of fields and pulses emulates the effects of measurements on the qubits; by leveraging this control Hamiltonian within a feedback loop, the team can counteract measurement disturbances, generating trajectories that appear to flow backward in time.
The team’s approach echoes the 19th-century “Maxwell’s demon” thought experiment, but instead of manipulating heat, they exploit knowledge of the quantum system’s state and measurement outcomes to drive anomalous processes. For quantum systems, which operate at that microscopic level, the tools we’ve constructed can manipulate the perceived arrow of time, leading to surprising, novel ways to control quantum systems. Source: https://www.lanl.gov/media/news/0319-reshaping-quantum-arrow Tags: Quantum News There is so much happening right now in the field of technology, whether AI or the march of robots. Adrian is an expert on how technology can be transformative, especially frontier technologies. But Quantum occupies a special space. Quite literally a special space. A Hilbert space infact, haha! Here I try to provide some of the news that is considered breaking news in the Quantum Computing and Quantum tech space. Latest Posts by Quantum News: Technische Universität Dortmund Demonstrates Control of Persistent Spin Helix Orientation in Quantum Wells March 20, 2026 Xanadu to Become First Publicly Listed Photonic Quantum Technology Company March 20, 2026 Beijing Academy of Quantum Information Sciences Implements Algorithm to Determine Multiple Molecular Energy Levels March 20, 2026