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Optics, technologies that leverage the behavior and properties of light, are the basis of many existing technological tools, most notably fiber communication systems that enable long-and short-distance high-speed communication between devices. Optical signals have a high information capacity and can be transmitted across longer distances.

Researchers at California Institute of Technology have recently developed a new device that could help to overcome some of the limitations of existing . This device, introduced in a paper published in Nature Photonics, is a lithium niobate-based device that can switch ultrashort light pulses at an extremely low optical pulse energy of tens of femtojoules.

“Unlike electronics, optics still lacks efficiency in required components for computing and signal processing, which has been a major barrier for unlocking the potentials of optics for ultrafast and efficient computing schemes,” Alireza Marandi, lead researcher for the study, told Phys.org. “In the past few decades, substantial efforts have been dedicated to developing all– that could address this challenge, but most of the energy-efficient designs suffered from slow switching times, mainly because they either used high-Q resonators or carrier-based nonlinearities.”

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A pair of UCLA bioengineers and a former postdoctoral scholar have developed a new class of bionic 3D camera systems that can mimic flies’ multiview vision and bats’ natural sonar sensing, resulting in multidimensional imaging with extraordinary depth range that can also scan through blind spots.

Powered by computational image processing, the camera can decipher the size and shape of objects hidden around corners or behind other items. The technology could be incorporated into autonomous vehicles or medical imaging tools with sensing capabilities far beyond what is considered state of the art today. This research has been published in Nature Communications.

In the dark, bats can visualize a vibrant picture of their surroundings by using a form of echolocation, or sonar. Their high-frequency squeaks bounce off their surroundings and are picked back up by their ears. The minuscule differences in how long it takes for the echo to reach the nocturnal animals and the intensity of the sound tell them in real time where things are, what’s in the way and the proximity of potential prey.

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A new method for shaping matter into complex shapes, with the use of ‘twisted’ light, has been demonstrated in research at the University of Strathclyde.

When are cooled to temperatures close to absolute zero (−273 degrees C), they stop behaving like particles and start to behave like waves.

Atoms in this condition, which are known as Bose–Einstein condensates (BECs), are useful for purposes such as realization of atom lasers, slow light, quantum simulations for understanding the complex behavior of materials like superconductors and superfluids, and the precision measurement technique of atom interferometry.

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Using a magnetically stirred liquid metal, researchers have reproduced a key feature of astrophysical accretion disks: a turbulence-based transfer of angular momentum.

Astrophysical disks are ubiquitous objects in the cosmic landscape: we observe them around matter-gobbling black holes and planet-forming stellar systems. The gas and dust in these disks slowly drift inward and eventually reach the central star or black hole. The energy released in this accretion process makes some of these disks very luminous. However, the physical mechanism responsible for this accretion remains elusive despite 40 years of active research. Now Marlone Vernet from Sorbonne University in France and his colleagues model astrophysical disks with an experimental system based on a rotating disk of liquid metal [1]. The novelty in this experiment is that the disk is set into rotation thanks to electrical currents and magnetic fields in a way that mimics gravity. The experiment provides strong evidence of angular momentum transport, which is thought to be a key feature in astrophysical accretion.

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Researchers have observed the formation of 2D ice on gold surfaces that were thought to be too hydrophilic and too rough to support this type of ice.

Mobile devices use facial recognition technology to help users quickly and securely unlock their phones, make a financial transaction or access medical records. But facial recognition technologies that employ a specific user-detection method are highly vulnerable to deepfake-based attacks that could lead to significant security concerns for users and applications, according to new research involving the Penn State College of Information Sciences and Technology.

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Mobile devices use facial recognition technology to help users quickly and securely unlock their phones, make a financial transaction or access medical records. But facial recognition technologies that employ a specific user-detection method are highly vulnerable to deepfake-based attacks that could lead to significant security concerns for users and applications, according to new research involving the Penn State College of Information Sciences and Technology.

The researchers found that most that use facial liveness verification—a feature of that uses computer vision to confirm the presence of a live user—don’t always detect digitally altered photos or videos of individuals made to look like a live version of someone else, also known as deepfakes. Applications that do use these detection measures are also significantly less effective at identifying deepfakes than what the app provider has claimed.

“In recent years we have observed significant development of facial authentication and verification technologies, which have been deployed in many security-critical applications,” said Ting Wang, associate professor of information sciences and technology and one principal investigator on the project. “Meanwhile, we have also seen substantial advances in deepfake technologies, making it fairly easy to synthesize live-looking facial images and video at little cost. We thus ask the interesting question: Is it possible for malicious attackers to misuse deepfakes to fool the facial verification systems?”

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If we could harness fusion to generate electricity, it would be one of the most efficient and least polluting sources of energy possible.

A major breakthrough in nuclear fusion has been confirmed a year after it was achieved at a laboratory in California.

Researchers at Lawrence Livermore National Laboratory’s (LLNL’s) National Ignition Facility (NIF) recorded the first case of ignition on August 8, 2021, the results of which have now been published in three peer-reviewed papers.

Nuclear fusion is the process that powers the Sun and other stars: heavy hydrogen atoms collide with enough force that they fuse together to form a helium atom, releasing large amounts of energy as a by-product. Once the hydrogen plasma “ignites”, the fusion reaction becomes self-sustaining, with the fusions themselves producing enough power to maintain the temperature without external heating.

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3D printed material:

MIT researchers manufactured objects made of flexible plastic and electrically conductive filaments. Some varieties of 3D-printed objects can now feel, using a new technique that builds sensors directly into their materials. 3D printing can be considered printing, although not as it’s traditionally been defined. The method opens opportunities for embedding sensors within architected materials, a class of materials whose mechanical properties are programmed through form and composition.

The researchers also created 3D editing software, known as MetaSense, to help users build interactive devices using these metamaterials. The new technique 3D-prints objects made from metamaterial substances made of grids of repeating cells. It was designed to conform to a person’s hand. When a user squeezes one of the flexible buttons, the resulting electric signals help control a digital synthesizer.

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Scientists in Germany and the US have predicted the most topologically complex knot ever found in a protein using AlphaFold, the artificial intelligence (AI) system developed by Google’s DeepMind. Their complete analysis of the data produced by AlphaFold also revealed the first composite knots in proteins: topological structures containing two separate knots on the same string. If the discovered protein knots can be recreated experimentally it will serve to verify the accuracy of predictions made by AlphaFold.

Proteins can fold to form complex topological structures. The most intriguing of these are protein knots – shapes that would not disentangle if the protein were pulled from both ends. Peter Virnau, a theoretical physicist at Johannes Gutenberg University Mainz, tells Physics World that there are currently around 20 to 30 known knotted proteins. These structures, Virnau explains, raise interesting questions around how they fold and why they exist.

A protein’s shape can be closely linked with its function, but while there are a few theories on the functionality and purpose of protein knots there is little hard evidence to back these up. Virnau says that they might help to keep the proteins stable, by being particularly resistant to thermal fluctuations, for instance, but these are open questions. While protein knots are rare, they also appear to be highly preserved by evolution.

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