More than two decades ago, scientists predicted that at ultra-low temperatures, many atoms could undergo ‘quantum superchemistry’ and chemically react as one. They’ve finally shown it’s real.
Category: particle physics – Page 157
Iron screws and other so-called ferromagnetic materials are made up of atoms with electrons that act like little magnets. Normally, the orientations of the magnets are aligned within one region of the material but are not aligned from one region to the next. Think of packs of tourists in Times Square pointing to different billboards all around them. But when a magnetic field is applied, the orientations of the magnets, or spins, in the different regions line up and the material becomes fully magnetized. This would be like the packs of tourists all turning to point at the same sign.
A team of scientists from Columbia, Nanjing University, Princeton, and the University of Munster, writing in the journal Nature, have presented the first experimental evidence of collective excitations with spin called chiral graviton modes (CGMs) in a semiconducting material.
To understand the relationship between the science fiction genre and the Many-Worlds Interpretation, let’s turn to two men – a scientist and a writer. The scientist is Hugh Everett III (1930−1982), a physicist who developed the notion of parallel universes based on an original interpretation of quantum mechanics. He proposed that a pre-formulated theory should be the basis of scientific measurement, quite the opposite of the traditional scientific process in which measurement preceded and determined the theory. But quantum particles do not behave normally, so quantum phenomena and their atomic dynamics cannot be measured by the Newtonian mechanics traditionally applied to the universe.
When Hugh Everett published “Relative State Formulation of Quantum Mechanics” in the Reviews of Modern Physics scientific journal (Volume 29, Issue 3, July — September 1957), his theory that there are many worlds existing in parallel at the same space and time as our own sounded like fantasy fiction to a skeptical scientific world.
While scientists scoffed for more than a decade after Everett published his theory, someone else entered the scene. His name was Philip K. Dick, a scruffy beatnik writer who tramped around Berkeley (California) looking for ways to describe this alternative reality – the one hiding behind our visible reality.
Curtin University-led research has discovered a rare dust particle trapped in an ancient extra-terrestrial meteorite that was formed by a star other than our sun.
A new fabrication process that could be used to build a quantum computer achieves an almost zero failure rate and has the potential to be scaled up, according to new research from engineers and physicists at UCL.
Gravitons, the particles thought to carry gravity, have never been seen in space – but something very similar has been detected in a semiconductor.
As transistors get smaller, they become increasingly inefficient and susceptible to errors, as electrons can leak through the device even when it is supposed to be switched off, by a process known as quantum tunneling. Researchers are exploring new types of switching mechanisms that can be used with different materials to remove this effect.
In the nanoscale structures that Professor Jan Mol, Dr. James Thomas, and their group study at Queen Mary’s School of Physical and Chemical Sciences, quantum mechanical effects dominate, and electrons behave as waves rather than particles. Taking advantage of these quantum effects, the researchers built a new transistor.
The transistor’s conductive channel is a single zinc porphyrin, a molecule that can conduct electricity. The porphyrin is sandwiched between two graphene electrodes, and when a voltage is applied to the electrodes, electron flow through the molecule can be controlled using quantum interference.
There’s a specter haunting the tunnels of a particle accelerator at CERN.
In the Super Proton Synchrotron, physicists have finally measured and quantified an invisible structure that can divert the course of the particles therein, and create problems for particle research.
It’s described as taking place in phase space, which can represent one or more states of a moving system. Since four states are required to represent the structure, the researchers view it as four-dimensional.
In a talk at the ongoing Rencontres de Moriond conference, the ATLAS collaboration presented the result of its latest test of a key principle of the Standard Model of particle physics known as lepton flavor universality. The precision of the result is the best yet achieved by a single experiment in decays of the W boson and surpasses that of the current experimental average.