The equipment that generates quantum entanglement is bulky and produces entangled photons just a pair at a time. Now scientists have created a device roughly one-third as thick as a penny that can yield complex webs of entangled photons—not just in pairs, but several pairs all linked together.
With the new observations we are seeing a mixture of particle physics being the new physics governing even long standing laws like gravity. Also that string theory is still alive and well. I think we may never know everything unless we essentially get to a type 5 civilization or beyond.
Finding cannot be explained by classical assumptions.
An international team of astrophysicists has made a puzzling discovery while analyzing certain star clusters. The finding challenges Newton’s laws of gravity, the researchers write in their publication. Instead, the observations are consistent with the predictions of an alternative theory of gravity. However, this is controversial among experts. The results have now been published in the Monthly Notices of the Royal Astronomical Society. The University of Bonn played a major role in the study.
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A team of researchers at Shanghai Jiao Tong University, working with a pair of colleagues from Harvard University, has developed a new way to synthesize single quantum nanomagnets that are based on metal-free, multi-porphyrin systems. In their paper published in the journal Nature Chemistry, the group describes their method and possible uses for it.
Molecular magnets are materials that are capable of exhibiting ferromagnetism. They are different from other magnets because their building blocks are composed of organic molecules or a combination of coordination compounds. Chemists have been studying their properties with the goal of using them to develop medical therapies such advanced magnetic resonance imaging, new kinds of chemotherapy and possibly magnetic-field-induced local hyperthermia therapy. In this new effort, the researchers have developed a way to create molecular nanomagnets with quantum properties.
The technique involved first synthesizing a monoporphyrin using what they describe as conventional “solution chemistry”—the monoporhyrins were created by using an atomic-force microscope to pull hydrogen atoms off of polyporphyrins. The researchers then applied the result to a base of gold, which they placed in an oven and heated to 80 °C. This forced the rings in the material to become chained. They then turned the oven up to 290°C and then let the material cook for another 10 minutes. This resulted in the formation of additional carbon cycles and the creation of quantum nanomagnets.
Black holes have properties characteristic of quantum particles, a new study reveals, suggesting that the puzzling cosmic objects can be at the same time small and big, heavy and light, or dead and alive, just like the legendary Schrödinger’s cat.
The new study, based on computer modeling, aimed to find the elusive connection between the mind-boggling time-warping physics of supermassive objects such as black holes and the principles guiding the behavior of the tiniest subatomic particles.
The computing power of quantum machines is currently still very low. Increasing performance is a major challenge. Physicists at the University of Innsbruck, Austria, now present a new architecture for a universal quantum computer that overcomes such limitations and could be the basis of the next generation of quantum computers soon.
Quantum bits (qubits) in a quantum computer serve as a computing unit and memory at the same time. Because quantum information cannot be copied, it cannot be stored in memory as in a classical computer. Due to this limitation, all qubits in a quantum computer must be able to interact with each other.
This is currently still a major challenge for building powerful quantum computers. In 2015, theoretical physicist Wolfgang Lechner, together with Philipp Hauke and Peter Zoller, addressed this difficulty and proposed a new architecture for a quantum computer, now named LHZ architecture after the authors.
Quantum computers, which can perform calculations much faster than traditional computers, have a big problem: They are prone to data storage and processing errors caused by disturbances from the environment like vibrations and radiation from warm objects.
But a discovery by scientists led by Nanyang Technological University, Singapore (NTU Singapore), on how electrons can be controlled at very low temperatures, suggests a way for addressing this problem and developing more robust and accurate quantum computers.
The team’s findings, which were published online in the Nature Communications journal in October 2022, showed, for the first time, that electrons can have strong interactions between them under certain conditions.
When we encounter metals in our day-to-day lives, we perceive them as shiny. That’s because common metallic materials are reflective at visible light wavelengths and will bounce back any light that strikes them. While metals are well suited to conducting electricity and heat, they aren’t typically thought of as a means to conduct light.
But in the burgeoning field of quantum materials, researchers are increasingly finding examples that challenge expectations about how things should behave. In new research published in Science Advances, a team led by Dmitri Basov, Higgins Professor of Physics at Columbia University, describes a metal capable of conducting light. “These results defy our daily experiences and common conceptions,” said Basov.
The work was led by Yinming Shao, now a postdoc at Columbia who transferred as a Ph.D. student when Basov moved his lab from the University of California San Diego to New York in 2016. While working with the Basov group, Shao has been exploring the optical properties of a semimetal material known as ZrSiSe. In 2020 in Nature Physics, Shao and his colleagues showed that ZrSiSe shares electronic similarities with graphene, the first so-called Dirac material discovered in 2004. ZrSiSe, however, has enhanced electronic correlations that are rare for Dirac semimetals.
HOW did our universe begin? This is among the most profound questions of all, and you would be forgiven for thinking it is impossible to answer. But Laura Mersini-Houghton says she has cracked it. A cosmologist at the University of North Carolina at Chapel Hill, she was born and raised under communist dictatorship in Albania, where her father was considered ideologically opposed to the regime and exiled. She later won a Fulbright scholarship to study in the US, forging a career in cosmology in which she has tackled the origins of the universe – and made an extraordinary proposal.
Mersini-Houghton’s big idea is that the universe in its earliest moments can be understood as a quantum wave function – a mathematical description of a haze of possibilities – that gave rise to many diverse universes as well as our own. She has also made predictions about how other universes would leave an imprint upon our own. Those ideas have been controversial, with some physicists arguing that her predictions are invalid. But Mersini-Houghton argues that they have been confirmed by observations of the radiation left over from the big bang, known as the cosmic microwave background.
Ultra-pure diamond wafers could be used for quantum memory in tomorrow’s ultra-powerful quantum computers.
Thermodynamic phases governed by the strong nuclear force have been linked together using multiple theoretical tools.
Quantum chromodynamics (QCD) is the theory of the strong nuclear force. On a fundamental level, it describes the dynamics of quarks and gluons. Like more familiar systems, such as water, a many-body system of quarks and gluons can exist in very different thermodynamic phases depending on the external conditions. Researchers have long sought to map the different corners of the corresponding phase diagram. New experimental probes of QCD—first and foremost the detection of gravitational waves from neutron-star mergers—allow for a more comprehensive view of this phase structure than was previously possible. Now Tuna Demircik at the Asia Pacific Center for Theoretical Physics, South Korea, and colleagues have put together models originally used in very different contexts to push forward a global understanding of the phases of QCD [1].
Phase transitions governed by the strong force require extreme conditions such as high temperatures and high baryon densities (baryons are three-quark particles such as protons and neutrons). The region of the QCD phase diagram corresponding to high temperatures and relatively low baryon densities can be probed by colliding heavy ions. By contrast, the region associated with high baryon densities and relatively low temperatures can be studied by observing single neutron stars. For a long time, researchers lacked experimental data for the phase space between these two regions, not least because it is very difficult to create matter under neutron-star conditions in the laboratory. This difficulty still exists, although collider facilities are being constructed that are intended to produce matter at higher baryon densities than is currently possible.
