Tag: quantum mechanics

Quantum Breakthrough? Scientists Demonstrate First Quantum Sensor Approaching the Heisenberg Limit

Korean Institute of Science and Technology (KIST) scientists have successfully demonstrated the world’s first ultra-precise, ultra-sensitive distributed quantum sensor network sensitive enough to approach the Heisenberg limit, where distinguishing the desired signal from the noise becomes impossible.

The approach is also among the first in the field to conduct experiments that simultaneously employ multiple quantum entangled photons, enabling unprecedented sensitivity and precision beyond single-entangled-photon approaches.

While previous approaches to a distributed quantum sensor network aimed to increase measurement precision, the new approach is the first to leverage this unprecedented level of precision for higher-resolution imaging. Using several quantum sensors in concert is similar to astronomers employing several observatories to measure a single phenomenon with more detail than any individual observatory could achieve on its own.

The research team behind the accomplishment suggests their approach could improve applications from space observation to medical imaging by offering previously unattainable fine details collected from multiple sensors working together rather than a lone sensor.

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Theory suggests that consciousness is a quantum process, connecting us all to the entire universe

Our minds feel very private and unique to each of us, yet many researchers suspect our consciousness might plug into something far bigger. A controversial new framework says a quantum entanglement trick could happen inside microtubules, the tiny protein tubes that scaffold every neuron in your head.

Mike Wiest, a neuroscientist at Wellesley College, thinks those tubes may carry quantum information that never stays put.

Quantum entanglement is a phenomenon in quantum physics where two or more particles become so deeply linked that the state of one instantaneously influences the state of the other, no matter how far apart they are.

When particles are entangled, their properties – such as spin, polarization, or momentum – are correlated in such a way that measuring one particle’s state automatically determines the other’s.

This strange connection defies classical logic and puzzled Einstein, who famously dismissed it as “spooky action at a distance.”

Despite its counterintuitive nature, scientists have experimentally confirmed entanglement countless times, and it now plays a crucial role in technologies like quantum computing and quantum cryptography.

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MIT’s Chilling Experiment That Could Prove Gravity Is Quantum

MIT researchers have found a bold new way to approach one of science’s biggest mysteries: is gravity truly a quantum force?

By chilling a tiny mirror to near absolute zero using lasers — a method traditionally used in atomic physics — they’ve opened a new experimental window into the intersection of quantum mechanics and gravity. This fusion of cutting-edge cooling and classical tools might finally let scientists observe whether gravity behaves like other quantum forces, a question that has puzzled physicists for decades.

The Gravity Puzzle: Is It Quantum?

One of the most profound open questions in modern physics is: “Is gravity quantum?”

While the other fundamental forces—electromagnetic, weak nuclear, and strong nuclear—have been successfully described by quantum theory, gravity still stands apart. So far, scientists haven’t been able to create a consistent quantum theory of gravity, leaving a major gap in our understanding of the universe.

“Theoretical physicists have proposed many possible scenarios, from gravity being inherently classical to fully quantum, but the debate remains unresolved because we’ve never had a clear way to test gravity’s quantum nature in the lab,” says Dongchel Shin, a PhD candidate in the MIT Department of Mechanical Engineering (MechE). “The key to answering this lies in preparing mechanical systems that are massive enough to feel gravity, yet quiet enough — quantum enough — to reveal how gravity interacts with them.”

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Physicists confirm the incredible existence of “time mirrors”

For decades, theoretical physicists tossed around the idea that time reflection, also known as “time mirrors,” might one day be demonstrated in a real-world experiment.

This idea seemed too big and wild, yet it kept popping up in serious discussions of quantum mechanics where equations hinted at surprising behavior.

A team led by Hady Moussa from the Advanced Science Research Center at the CUNY Graduate Center (CUNY ASRC) in New York City has now confirmed that these mysterious events actually exist.

They pulled off a successful test by changing the properties of a device in a quick, uniform way so that signals reversed direction in time.

Understanding time mirrors

This sort of time flip has been described as looking into a mirror and spotting your back instead of your face. It sounds like science fiction, but it has a basis in real physics.

Researchers had predicted for more than 50 years that sudden shifts in a wave’s environment could trigger such reversals.

Time reflections differ from everyday mirror views in one crucial way. Instead of light or sound bouncing back in space, the wave is forced to reverse its flow in time.

That shift causes the frequency of the wave to change, sparking a chain reaction of interesting phenomena in the system.

In normal reflections, you see an immediate image or hear an echo. A time reflection, on the other hand, makes part of the signal run backward.

There is no need for any speculation about time travel, though, since these effects involve a swift flip in the medium’s physical traits.

Time mirrors and metamaterials

To achieve this, the group used an engineered metamaterial designed to control electromagnetic wave behavior in unusual ways. Metamaterials allow scientists to manipulate waves far beyond ordinary mirrors or lenses.

By carefully adjusting electronic components on a strip of metal, they introduced a sudden jump that reversed the direction of incoming signals. They filled the strip with electronic switches hooked to capacitor banks.

That arrangement supplied the necessary burst of energy to force the wave to flip direction in time, an effect that used to be considered nearly impossible with accessible power.

The outcome was a time-reversed copy of the original wave, appearing just as predicted but never before seen with clarity.

Adjusting the system’s impedance at the right instant was key. Impedance is a measure of how much a structure resists electric current, and doubling it turned out to be the trick for flipping the wave in time.

By pulling this off in a lab setting, they proved that the energy hurdle can be overcome when conditions are precisely controlled.

Past attempts had failed because uniform shifts across the entire device were tough to generate, but the new approach surmounted that barrier.

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‘Dark photon’ theory of light aims to take down the famous double-slit experiment, upending quantum physics

For centuries, most scientists have shared the belief that light behaves as both a wave and a particle. This idea, then, became the central component to quantum theory, sprouting the field of science known as quantum mechanics.

The double-slit experiment supported the idea, showing bright and dark bands that indicated wave-like interference. But now, a new study suggests that this experiment might not lock us into seeing light as a wave.

According to the experts, we can interpret those interference bands using quantum particles alone.

The research was led by Gerhard Rempe, the director of the Max Planck Institute for Quantum Optics. He teamed up with collaborators at Federal University of São Carlos and ETH Zurich for the study.

Modern physics and our view of light

In 1801, Thomas Young introduced an experiment by shining light through two narrow openings to produce intersecting fringes on a screen. His findings led many to conclude that light must be a wave.

A century later, quantum mechanics began to take shape, revealing that quantum particles like electrons could mimic wave-like light interference too.

Albert Einstein’s work on the photoelectric effect showed that light travels in discrete packets called photons. Niels Bohr then elaborated on wave-particle duality, ushering in one of the cornerstones of modern physics.

Dark and visible photons

The new approach from the research team explores the concept of bright and dark modes.

In their view, interference patterns can emerge from combining “detectable” and “undetectable” photon states. These bright states interact with an observer, while dark states remain hidden.

Such hidden photons might linger at places where we would normally think the light cancels out. Observers who try to track the path of these photons alter the state, flipping what was dark into bright or vice versa.

From this perspective, the light pathways can be viewed as quantum superpositions, rather than purely classical wave interference.

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Laser Light Transformed Into a Supersolid in Groundbreaking Experiment

An international team of physicists has transformed laser light into a supersolid, marking an entirely new process for achieving this mysterious state of matter.

On the quantum level, matter often exhibits strange behaviors, and the supersolid state is one of the most counterintuitive examples. In this state, atoms arrange into a crystal lattice like a solid but also flow without friction, a property typically associated with liquids.

The Quest to Understand Supersolids

Scientists first proposed the idea of a solid that could demonstrate fluid-like flow in the 1960s, with theoretical exploration intensifying in the 1970s.

Helium was initially considered the most promising candidate for achieving this exotic phase of matter. However, early experiments attempting to produce a solid with superfluid properties yielded disappointing results. In the 1980s, physicist John Goodkind used ultrasound techniques to identify anomalies in matter that suggested supersolids might be feasible.

By the 2000s, new experimental data provided stronger hints of supersolid behavior, though some findings conflicted with theoretical predictions, making the state even more elusive.

Creating a Supersolid With Laser Light

For decades, researchers believed that achieving a supersolid state required ultracold atomic Bose-Einstein condensates combined with electromagnetic fields. This method, which was only successfully demonstrated in recent years, produced a material structured like table salt but also capable of flowing.

The latest research, however, takes an entirely different approach, creating a supersolid without using atoms at all.

The team began with a piece of gallium oxide designed with precise ridges to interact with an incoming laser beam. When the laser light struck the semiconductor’s ridges, it produced a quasiparticle known as a polariton. The shape of the ridges then constrained the polariton’s motion, forcing it into a supersolid state.

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Scientists Produced a Particle of Light That Simultaneously Accessed 37 Different Dimensions

Classical and quantum mechanics don’t really get along as the science of the subatomic can get, well, weird. Take, for instance, quantum entanglement, which says that the state of one particle can be determined by examining the state of its entangled pair regardless of distance. This strange fact flies in the face of classical physics, and even led Albert Einstein to famously describe this quantum quirk as “spooky action at a distance.”

This is what is known as “quantum nonlocality,” where objects are influenced across distances (seeming beyond the speed of light) whereas classical physics follows local theory, the idea that objects are influenced by their immediate surroundings. This is a pretty sharp divide as explained by the famous no-go theorem known as the Greenberger–Horne–Zeilinger (GHZ) paradox, which essentially details how quantum theory cannot be described by local realistic description.

Named for the physicists who described the paradox in 1989, GHZ-type paradoxes show that when particles can only be influenced by proximity they produce mathematical impossibilities. As New Scientist reports, the paradox can even be expressed through a calculation where 1 equals -1. This paradox is useful in showing how quantum properties can not be described using classical means, but a new paper published in the journal Science Advances, decided to see just how strange these paradoxes could get.

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Team presents first demonstration of quantum teleportation over busy internet cables

Northwestern University engineers are the first to successfully demonstrate quantum teleportation over a fiberoptic cable already carrying internet traffic.

The discovery introduces the new possibility of combining quantum communication with existing internet cables—greatly simplifying the infrastructure required for distributed quantum sensing or computing applications.

The study is published on the arXiv preprint server and is due to appear in the journal Optica.

“This is incredibly exciting because nobody thought it was possible,” said Northwestern’s Prem Kumar, who led the study. “Our work shows a path towards next-generation quantum and classical networks sharing a unified fiberoptic infrastructure. Basically, it opens the door to pushing quantum communications to the next level.”

An expert in quantum communication, Kumar is a professor of electrical and computer engineering at Northwestern’s McCormick School of Engineering, where he directs the Center for Photonic Communication and Computing.

Only limited by the speed of light, quantum teleportation could make communications nearly instantaneous. The process works by harnessing quantum entanglement, a technique in which two particles are linked, regardless of the distance between them. Instead of particles physically traveling to deliver information, entangled particles exchange information over great distances—without physically carrying it.

“In optical communications, all signals are converted to light,” Kumar explained. “While conventional signals for classical communications typically comprise millions of particles of light, quantum information uses single photons.”

Before Kumar’s new study, conventional wisdom suggested that individual photons would drown in cables filled with the millions of light particles carrying classical communications. It would be like a flimsy bicycle trying to navigate through a crowded tunnel of speeding heavy-duty trucks.

Kumar and his team, however, found a way to help the delicate photons steer clear of the busy traffic. After conducting in-depth studies of how light scatters within fiberoptic cables, the researchers found a less crowded wavelength of light to place their photons. Then, they added special filters to reduce noise from regular internet traffic.

“We carefully studied how light is scattered and placed our photons at a judicial point where that scattering mechanism is minimized,” Kumar said. “We found we could perform quantum communication without interference from the classical channels that are simultaneously present.”

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Physicists Baffled by Odd Quasiparticle That Seems to Have No Mass—Until It Changes Direction

Scientists report the first known observation of a variety of quasiparticle that exhibits a very peculiar behavior: it appears to have mass, but only while moving in one direction.

Scientists at Pennsylvania State University recently succeeded in detecting the unusual quasiparticle while conducting studies involving a semi-metallic crystalline material. Known as a semi-Dirac fermion, this unique formation of particles was first theorized more than a decade ago, but until now had never been directly observed.

The discovery potentially paves the way toward future advances in a range of emerging technologies that include power storage and novel forms of sensor technologies.

Detecting a Novel Quasiparticle

Quasiparticles are small collections of particles that normally appear within crystal lattices or under other special conditions, which generally possess both momentum and position, and under certain conditions may also be considered particles.

Discovering a novel quasiparticle like a semi-Dirac fermion had not been something Yinming Shao, assistant professor of physics at Penn State and lead author of a new paper revealing the discovery, had anticipated when he and his colleagues began experimenting with ZrSiS, a semi-metal crystal material that became the focus of their efforts.

“We weren’t even looking for a semi-Dirac fermion when we started working with this material, but we were seeing signatures we didn’t understand—and it turns out we had made the first observation of these wild quasiparticles that sometimes move like they have mass and sometimes move like they have none.”

Particles Without Mass

More than a century ago, Einstein’s theory of general relativity predicted that anything moving at the speed of light will have no mass. Because of this, physicists already recognize that a particle can essentially be massless under certain circumstances, namely when its energy comes entirely from its motion. Under such conditions, particles are recognized as manifestations of energy moving at the speed of light, such as in the case of photons.

However, quasiparticles moving through solid materials like crystalline structures can sometimes behave differently. In the observations of the Penn State research team, this apparently resulted in the appearance of particles that have mass in only one direction.

Beginning in 2008, it was initially predicted that mass-shifting properties might be observed in certain kinds of quasiparticles, which provided the theoretical framework for semi-Dirac fermions. Based on these initial predictions by scientists with the University of California, Davis and Université Paris Sud in France, such quasiparticles would seemingly be massless when moving in one direction but would almost paradoxically appear to possess mass when moving in another direction.

Shao and the Penn State team happened upon the discovery of such bizarre quasiparticle behavior while utilizing what is known as magneto-optical spectroscopy, which allows researchers to observe infrared light reflected off materials that are placed under the influence of strong magnetic fields.

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Groundbreaking Study Affirms Quantum Basis for Consciousness: A Paradigm Shift in Understanding Human Nature

A groundbreaking study has provided experimental evidence suggesting a quantum basis for consciousness.

By demonstrating that drugs affecting microtubules within neurons delay the onset of unconsciousness caused by anesthetic gases, the study supports the quantum model over traditional classical physics theories. This quantum perspective could revolutionize our understanding of consciousness and its broader implications, potentially impacting the treatment of mental illnesses and our understanding of human connection to the universe.

Exploring the Quantum Basis of Consciousness

For decades, one of the most fundamental and vexing questions in neuroscience has been: what is the physical basis of consciousness in the brain? Most researchers favor classical models, based on classical physics, while a minority have argued that consciousness must be quantum in nature, and that its brain basis is a collective quantum vibration of “microtubule” proteins inside neurons.

New research by Wellesley College professor Mike Wiest and a group of Wellesley College undergraduate students has yielded important experimental results relevant to this debate, by examining how anesthesia affects the brain. Wiest and his research team found that when they gave rats a drug that binds to microtubules, it took the rats significantly longer to fall unconscious under an anesthetic gas. The research team’s microtubule-binding drug interfered with the anesthetic action, thus supporting the idea that the anesthetic acts on microtubules to cause unconsciousness.

“Since we don’t know of another (i.e,. classical) way that anesthetic binding to microtubules would generally reduce brain activity and cause unconsciousness,” Wiest says, “this finding supports the quantum model of consciousness.”

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