Category Physics

Smart Atomic Cloud Solves Heisenberg’s observation problem

1. The atomic part of the hybrid experiment. The atoms are contained in a micro-cell inside the magnetic shield seen in the middle. Photo: Ola J. Joensen 2. The optomechanical part of the hybrid experiment. The cryostat seen in the middle houses the vibrating membrane whose quantum motion is measured. Photo: Ola J. Joensen 3, If laser light used to measure motion of a vibrating membrane (left) is first transmitted through an atom cloud (center) the measurement sensitivity can be better than standard quantum limits envisioned by Bohr and Heisenberg. Photo: Bastian Leonhardt Strube and Mads Vadsholt

1. The atomic part of the hybrid experiment. The atoms are contained in a micro-cell inside the magnetic shield seen in the middle. Photo: Ola J. Joensen 2. The optomechanical part of the hybrid experiment. The cryostat seen in the middle houses the vibrating membrane whose quantum motion is measured. Photo: Ola J. Joensen 3, If laser light used to measure motion of a vibrating membrane (left) is first transmitted through an atom cloud (center) the measurement sensitivity can be better than standard quantum limits envisioned by Bohr and Heisenberg. Photo: Bastian Leonhardt Strube and Mads Vadsholt

University of Copenhagen scientists have developed a hands-on answer to a challenge linked to Heisenberg’s Uncertainty Principle...

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Why you might Trust a Quantum Computer with Secrets, even over the Internet

1. Flow Ambiguity: A Path Towards Classically Driven Blind Quantum Computation. Physical Review X, 2017; 7 (3) DOI: 10.1103/PhysRevX.7.031004 2. Illustration of an exemplary run of Protocol 1

1. Flow Ambiguity: A Path Towards Classically Driven Blind Quantum Computation. Physical Review X, 2017; 7 (3) DOI: 10.1103/PhysRevX.7.031004
2. Illustration of an exemplary run of Protocol 1

Researchers suggest you could operate a quantum computer in the cloud without revealing your data or the program you’re running. Here’s the scenario: you have sensitive data and a problem that only a quantum computer can solve. You have no quantum devices yourself. You could buy time on a quantum computer, but you don’t want to give away your secrets. What can you do? Writing in Physical Review X on 11 July, researchers in Singapore and Australia propose a way you could use a quantum computer securely, even over the internet. The technique could hide both your data and program from the computer itself...

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Soft, Stretchy Fabric-based Sensors for Wearable Robots

1. This prototype glove includes soft sensors that are capable of registering movement of each finger individually. Credit: Wyss Institute at Harvard University 2. The silicone-textile hybrid sensors are highly flexible and resilient, making them excellent candidates for sensing body movement. Credit: Wyss Institute at Harvard University

1. This prototype glove includes soft sensors that are capable of registering movement of each finger individually. Credit: Wyss Institute at Harvard University 2. The silicone-textile hybrid sensors are highly flexible and resilient, making them excellent candidates for sensing body movement. Credit: Wyss Institute at Harvard University

Hybrid silicone-fabric sensor detects fine motor movements by flexing with the body. Wearable technologies – from heart rate monitors to virtual reality headsets – are exploding in popularity in both the consumer and research spaces, but most of the electronic sensors that detect and transmit data from wearables are made of hard, inflexible materials that can restrict both the wearer’s natural movements and the accuracy of the data collected...

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Carbon Displays Quantum Effects

They played a key role in demonstrating the unusual behavior of carbon: Tim Schleif (left) and Joel Mieres Perez (right). Credit: © RUB, Marquard

They played a key role in demonstrating the unusual behavior of carbon: Tim Schleif (left) and Joel Mieres Perez (right). Credit: © RUB, Marquard

Chemists at Ruhr-Universität Bochum have found evidence that carbon atoms cannot only behave like particles but also like waves. This quantum-mechanical property is well-known for light particles such as electrons or hydrogen atoms. However, researchers have only rarely observed the wave-particle duality for heavy atoms, such as carbon. “Our result is one of few examples showing that carbon atoms can display quantum effects,” says Sander. Specifically, carbon atoms can tunnel. They thus overcome an energetic barrier, although they do not actually possess enough energy to do that.

Wolfram Sander explains the paradox: “It’s as though a tiger has ...

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