The uncertainty inherent to quantum mechanics has long left physicists wondering whether the observations we make on the quantum level reflect reality — a new test suggests they do
Category: quantum physics – Page 26
History of quantum mechanics
The history of quantum mechanics is a fundamental part of the history of modern physics. The major chapters of this history begin with the emergence of quantum ideas to explain individual phenomena—blackbody radiation, the photoelectric effect, solar emission spectra—an era called the Old or Older quantum theories. [ 1 ]
Building on the technology developed in classical mechanics, the invention of wave mechanics by Erwin Schrödinger and expansion by many others triggers the “modern” era beginning around 1925. Paul Dirac’s relativistic quantum theory work led him to explore quantum theories of radiation, culminating in quantum electrodynamics, the first quantum field theory. The history of quantum mechanics continues in the history of quantum field theory. The history of quantum chemistry, theoretical basis of chemical structure, reactivity, and bonding, interlaces with the events discussed in this article.
The phrase “quantum mechanics” was coined (in German, Quantenmechanik) by the group of physicists including Max Born, Werner Heisenberg, and Wolfgang Pauli, at the University of Göttingen in the early 1920s, and was first used in Born and P. Jordan’s September 1925 paper “Zur Quantenmechanik”. [ 2 ] [ 3 ] [ 4 ].
Quantum teleportation coexisting with classical communications in optical fiber
Quantum teleportation was achieved over the internet for the first time
[ https://www.sciencealert.com/quantum-teleportation-was-achie…first-time]
The ability for quantum and conventional networks to operate in the same optical fibers would aid the deployment of quantum network technology on a large scale. Quantum teleportation is a fundamental operation in quantum networking, but has yet to be demonstrated in fibers populated with high-power conventional optical signals. Here we report, to the best of our knowledge, the first demonstration of quantum teleportation over fibers carrying conventional telecommunications traffic. Quantum state transfer is achieved over a 30.2-km fiber carrying 400-Gbps C-band classical traffic with a Bell state measurement performed at the fiber’s midpoint. To protect quantum fidelity from spontaneous Raman scattering noise, we use optimal O-band quantum channels, narrow spectro-temporal filtering, and multi-photon coincidence detection. Fidelity is shown to be well maintained with an elevated C-band launch power of 18.7 dBm for the single-channel 400-Gbps signal, which we project could support multiple classical channels totaling many terabits/s aggregate data rates. These results show the feasibility of advanced quantum and classical network applications operating within a unified fiber infrastructure.
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When a Black Hole Becomes a White Hole — and Shoots a Jet Across the Universe.
🌌 Have you ever wondered what happens inside a black hole — where physics seems to break? Einstein’s equations say it collapses forever… but quantum geometry tells a different story.
At the tiniest scales, spacetime itself pushes back. When curvature becomes extreme, a hidden repulsive side of gravity awakens — a mirror twin of the usual attraction. We call this curvature duality:
New model can detect ballistic electrons under realistic conditions
Ballistic electrons are among the most fascinating phenomena in modern quantum materials. Unlike ordinary electrons, they do not scatter off imperfections in the material and therefore travel from A to B with almost no resistance—like a capsule in a pneumatic tube. This behavior often occurs in confined one- or two-dimensional materials.
A problem that takes quantum computers an unfathomable amount of time to solve
It’s a well-known fact that quantum calculations are difficult, but one would think that quantum computers would facilitate the process. In most cases, this is true.
Quantum bits, or qubits, use quantum phenomena, like superposition and entanglement, to process many possibilities simultaneously. This allows for exponentially faster computing for complex problems. However, Thomas Schuster, of California Institute of Technology, and his research team have given quantum computers a problem that even they can’t solve in a reasonable amount of time—recognizing phases of matter of unknown quantum states.
The team’s research can be found in a paper published on the arXiv preprint server.
Researchers realize a driven-dissipative Ising spin glass using a cavity quantum electrodynamics setup
Spin glasses are physical systems in which the small magnetic moments of particles (i.e., spins) interact with each other in a random way. These random interactions between spins make it impossible for all spins to satisfy their preferred alignments; a condition known as ‘frustration.
Researchers at Stanford University recently realized a new type of spin glass, namely a driven-dissipative Ising spin glass in a cavity quantum electrodynamics (QED) experimental setup. Their paper, published in Physical Review Letters, is the result of over a decade of studies focusing on creating spin glasses with cavity QED.
“Spin glasses are a general model for complex systems, and specifically for neural networks—spins serve as neurons connected by their mutually frustrating interactions,” Benjamin Lev, senior author of the paper, told Phys.org.
Scientists create new type of semiconductor that holds superconducting promise
Scientists have long sought to make semiconductors—vital components in computer chips and solar cells—that are also superconducting, thereby enhancing their speed and energy efficiency and enabling new quantum technologies. However, achieving superconductivity in semiconductor materials such as silicon and germanium has proved challenging due to difficulty in maintaining an optimal atomic structure with the desired conduction behavior.
In a paper published in the journal Nature Nanotechnology, an international team of scientists reports producing a form of germanium that is superconducting—able to conduct electricity with zero resistance, which allows currents to flow indefinitely without energy loss, resulting in greater operational speed that requires less energy.
“Establishing superconductivity in germanium, which is already widely used in computer chips and fiber optics, can potentially revolutionize scores of consumer products and industrial technologies,” says New York University physicist Javad Shabani, director of NYU’s Center of Quantum Information Physics and the university’s newly established Quantum Institute, one of the paper’s authors.
‘Singing’ electrons synchronize in Kagome crystals, revealing geometry-driven quantum coherence
Physicists at the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) in Hamburg have discovered a striking new form of quantum behavior. In star-shaped Kagome crystals—named after a traditional Japanese bamboo-basket woven pattern—electrons that usually act like a noisy crowd suddenly synchronize, forming a collective “song” that evolves with the crystal’s shape. The study, published in Nature, reveals that geometry itself can tune quantum coherence, opening new possibilities to develop materials where form defines function.
Quantum coherence—the ability of particles to move in synchrony like overlapping waves—is usually limited to exotic states such as superconductivity, where electrons pair up and flow coherently. In ordinary metals, collisions quickly destroy such coherence.
But in the Kagome metal CsV₃Sb₅, after sculpting tiny crystalline pillars just a few micrometers across and applying magnetic fields, the MPSD team observed Aharonov–Bohm-like oscillations in electrical resistance. Thus showing that electrons were interfering collectively, remaining coherent far beyond what single-particle physics would allow.