Scientists make quantum time flow backward in stunning physics breakthrough Date: July 3, 2026 Source: Los Alamos National Laboratory Summary: Researchers have created quantum control techniques that can make a system appear to run backward in time. By precisely managing quantum measurements, they can reshape the system's arrow of time and even harvest energy from the measurement process itself. The breakthrough could lead to more powerful quantum computers, quantum batteries, and other advanced technologies. Share: FULL STORY Researchers Make Quantum Time Flow Backward Researchers have taken a major step toward reversing the quantum arrow of time—and discovered a surprising new way to harvest energy in the process. Credit: AI/ScienceDaily.com Scientists have developed a new way to control quantum systems that can make their behavior appear more consistent with time moving backward rather than forward. The research, published in Physical Review X, introduces quantum control protocols that reshape a system's "arrow of time," the concept that time naturally moves in only one direction. The approach could eventually support new methods for extracting energy from quantum systems and preparing quantum states. A quantum system, such as a group of qubits, follows the rules of quantum mechanics rather than classical physics. Using the newly developed control protocols, researchers can suppress the usual emergence of the arrow of time or even reverse its apparent direction, making quantum processes look as though they are unfolding backward. As a demonstration of the technique, the team also created a measurement engine that can harvest energy from the act of making quantum measurements. "Unlike phenomena we observe around us, 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. "In other words, those laws of physics are symmetrical under time reversal; the equations work just as well if you reverse time. 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." Engineering Time Reversed Quantum Behavior In everyday classical physics, making a measurement has little effect on the object being observed. Quantum systems behave very differently. Measuring them randomly changes their state, naturally creating an arrow of time. To overcome that effect, the researchers combined measurements with feedback to produce time reversed stochastic trajectories. This allowed quantum systems to follow paths that appear consistent with time flowing in reverse. The team accomplished this by designing a control Hamiltonian, a carefully planned sequence of fields and pulses that reproduces the effects of quantum measurements. When incorporated into a feedback system, the Hamiltonian can cancel, strengthen, or even overcorrect the disturbances caused by measurements. As a result, the system can generate trajectories that correspond to stretched, blurred, or inverted arrows of time. A Quantum Version of Maxwell's Demon The work also builds on the famous 19th century thought experiment known as "Maxwell's demon." In that scenario, a hypothetical observer selectively sorts hot and cold particles, apparently reducing entropy and challenging the second law of thermodynamics, which states that entropy naturally increases or remains constant. (Later physics has shown that the second law is not violated when all sources of thermodynamic costs are accounted for.) The Los Alamos team's quantum "demon" uses information about a quantum system's state and measurement results to produce similarly unusual behavior, effectively reversing the system's natural arrow of time. Extracting Energy From Quantum Measurements The new control methods also allow researchers to influence how energy moves into and out of a quantum system. This capability could power a continuous measurement engine that extracts useful energy directly from the monitoring process. In this framework, quantum measurements become a thermodynamic resource that can be tapped to perform work, such as driving another quantum process or storing energy in a quantum battery. Looking ahead, the researchers plan to experimentally demonstrate Hamiltonian based measurement processes for quantum feedback control using superconducting qubits. These systems support rapid feedback, highly efficient detection, and have already been used to implement quantum versions of Maxwell's demon. Future studies will also apply the new techniques to develop improved quantum state preparation protocols.

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Supporting Antifa in an educational context would amplify the anti-democratic nature of ideological capture to a dangerous degree. Antifa's core characteristics Antifa is a loose, decentralized far-left militant movement that explicitly rejects liberal democracy in favor of direct action, deplatforming, and sometimes violence to combat perceived fascism. It opposes free speech for opponents, views institutions (including schools) as tools for revolutionary change, and often aligns with anarchist or accelerationist tactics. Open support for it goes beyond standard left politics into endorsing extra-legal methods.Why educator or institutional support crosses a line Undermines the rule of law — Public schools are state institutions bound by democratic norms (elections, due process, free expression under the First Amendment). Teachers or curricula that fantasize, romanticize, excuse, or promote Antifa-style tactics (property destruction, no-platforming, "by any means necessary") teach contempt for democratic mechanisms. This is especially toxic for youth, who are still forming civic habits. Heightens indoctrination risk — In captured systems (e.g., activist factions within unions like Oakland Education Association), materials that frame Antifa sympathetically as heroic resisters fit the pattern of one-sided narratives. We've seen unauthorized "teach-ins" and "liberatory education" pushes in Oakland and similar districts that critics argue veer into political activism rather than balanced analysis. Glorifying militant groups adds an endorsement of violence to ideological skew. rethinkingschools.org Disproportionate harm — For less-educated or captive audiences (K-12 students), this normalizes extremism. It can desensitize youth to political violence, chill dissent in classrooms, and erode trust in democratic institutions. Post-2020 riots and campus disruptions showed real-world spillover. Anti-democratic double standard — Democracy allows debate over ideas, even radical ones. But state-funded educators actively supporting a movement that rejects debate itself (via doxxing, riots, or "punch a Nazi" rhetoric that expands "Nazi" to include mainstream conservatives) is viewpoint discrimination with state power behind it. It's the opposite of pluralism. Reality checkNot every progressive educator supports Antifa—many explicitly reject its violence. Direct endorsements in official curricula are rare and often opposed by districts when publicized. However, tolerance or soft-pedaling in activist teacher circles, reading lists that lionize radical left figures, or failure to condemn Antifa-linked tactics does occur in highly polarized blue-city environments and feeds the capture critique.This would make the problem not just bias, but incitement against democratic norms. Reforms emphasizing classical civics, viewpoint balance, and strict political neutrality in K-12 become even more urgent. Public education should prepare citizens for democracy, not recruit for its rejection..