Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: quantum physics – Page 246

Quantum Teleportation Just Got Real: Achieving 90% Fidelity Amidst Noise

Scientists have advanced quantum teleportation by mitigating noise interference through a novel method involving hybrid entanglement, achieving close to 90% fidelity in teleporting quantum states, which could significantly enhance secure quantum communication.

A research team led by Academician Guangcan Guo from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS), in collaboration with the research team at the University of Turku, Finland, successfully overcame environmental noise to achieve high-fidelity quantum teleportation by utilizing multipartite hybrid entanglement. Their findings were published recently in the journal Science Advances.

Overcoming Challenges in Quantum Teleportation.

Retrocausality and Quantum Mechanics

The exact empirical evidence for retrocausality does not exist yet, but the existing empirical data as those from Bell tests may be interpreted in a way to support the retrocausal framework.

Have you ever thought that future states could affect the events that have occurred in the past? Although this idea sounds quite bizarre, it is indeed possible according to a quantum mechanical effect called retrocausality. According to the concept, causality and time do not work in the conventional sense and remarkably, an effect can predate its cause, thus reversing the directionality of time as well.

Usually, in the classical world, this is not what we actually experience. For every cause, there is a corresponding effect, but they work sequentially rather than in the reverse way. Conventional thought process suggests that once a particular event has occurred, there’s almost zero probability that it can be reversed. The physical reason is simple, and it has to do with the arrow of time. In general, the arrow of time points in a single forward direction and this is one of the major unsolved challenges of the foundations of physics because physicists are uncertain of why the nature of time is such.

Quantum Magic: How “Super Photons” Are Shaping the Future of Physics

Researchers at the University of Bonn have demonstrated that super photons, or photon Bose-Einstein condensates, conform to fundamental physics theorems, enabling insights into properties that are often difficult to observe.

Under suitable conditions, thousands of particles of light can merge into a type of “super photon.” Physicists call such a state a photon Bose-Einstein condensate. Researchers at the University of Bonn have now shown that this exotic quantum state obeys a fundamental theorem of physics. This finding now allows one to measure properties of photon Bose-Einstein condensates which are usually difficult to access. The study was published on June 3 in the journal Nature Communications.

If many atoms are cooled to a very low temperature confined in a small volume, they can become indistinguishable and behave like a single “super particle.” Physicists also call this a Bose-Einstein condensate or quantum gas. Photons condense based on a similar principle and can be cooled using dye molecules. These molecules act like small refrigerators and swallow the “hot” light particles before spitting them out again at the right temperature.

Quantum mechanics and the puzzle of human consciousness

Some scientists speculate that the strange happenings in this microscopic realm may hold the key to understanding consciousness. But scant evidence has left the majority skeptical.

That includes Christof Koch, Ph.D., meritorious investigator at the Allen Institute. As he wrote in his recent book, Then I am myself the world, “the brain is wet and warm, hardly conducive to subtle quantum interactions.”

But despite his skepticism, Koch is collaborating with scientists at Google Quantum AI and universities worldwide to explore the role quantum mechanics might play in shaping consciousness. A paper published in Entropy offers their novel theory on the links between quantum mechanics and consciousness and details a series of experiments to test it.

New theory links quantum geometry to electron-phonon coupling

A new study published in Nature Physics introduces a theory of electron-phonon coupling that is affected by the quantum geometry of the electronic wavefunctions.

The movement of electrons in a lattice and their interactions with the lattice vibrations (or phonons) play a pivotal role in phenomena like superconductivity (resistance-free conductivity).

Electron-phonon coupling (EPC) is the interaction between free electrons and phonons, which are quasiparticles representing the vibrations of a crystal lattice. EPC leads to the formation of Cooper pairs (pairs of electrons), responsible for superconductivity in certain materials.

A route to scalable Majorana qubits

Researchers at QuTech have found a way to make Majorana particles in a two-dimensional plane. This was achieved by creating devices that exploit the combined material properties of superconductors and semiconductors. The inherent flexibility of this new 2D platform should allow one to perform experiments with Majoranas that were previously inaccessible. The results are published in Nature.

Quantum dot based metasurface enables two objects to exist in the same space

In relationships, sharing closer spaces naturally deepens the connection as bonds form and strengthen through increasing shared memories. This principle applies not only to human interactions but also to engineering. Recently, an intriguing study was published demonstrating the use of quantum dots to create metasurfaces, enabling two objects to exist in the same space.

Professor Junsuk Rho from the Department of Mechanical Engineering, the Department of Chemical Engineering, and the Department of Electrical Engineering, PhD candidates Minsu Jeong, Byoungsu Ko, and Jaekyung Kim from the Department of Mechanical Engineering, and Chunghwan Jung, a PhD candidate, from the Department of Chemical Engineering at Pohang University of Science and Technology (POSTECH) employed Nanoimprint Lithography (NIL) to fabricate metasurfaces embedded with quantum dots, enhancing their luminescence efficiency. Their research was recently published in Nano Letters (“Printable Light-Emitting Metasurfaces with Enhanced Directional Photoluminescence”).

(Left) Schematic diagram of the fabrication of a luminescence-controlled metasurface using the nanoimprint lithography process. (Right) Experiment evaluating the performance of the metasurface’s luminescence control. (Image: POSTECH)

A Missing Piece in the Big Bang Theory Has Surfaced

In research published earlier this year, physicists from the University of Hyderabad in India say they’re on the path to solving one of the universe’s biggest outstanding problems. Since Edwin Hubble realized the universe is always expanding nearly 100 years ago, scientists have used the “Hubble constant” in calculations on virtually every scale in the universe. But today, estimates for the Hubble constant don’t always align, with a difference of up to 10 percent between calculations made using different methods. (When someone at NASA mixes up meters and yards and loses an entire spacecraft, that’s not even a full 10 percent deviation.)

The paper appears in the peer reviewed journal Classical and Quantum Gravity. The journal has an ongoing, periodically updated “focus issue” specifically about this measurement tension, and the editors explain the problem there—scientists can’t say for sure that the different Hubble constants measured are actually different, rather than just observation or calibration issues.