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Apr 13, 2021

The observation of Kardar-Parisi-Zhang hydrodynamics in a quantum material

Posted by in categories: information science, mathematics, particle physics, quantum physics

Classical hydrodynamics laws can be very useful for describing the behavior of systems composed of many particles (i.e., many-body systems) after they reach a local state of equilibrium. These laws are expressed by so-called hydrodynamical equations, a set of mathematical equations that describe the movement of water or other fluids.

Researchers at Oak Ridge National Laboratory and University of California, Berkeley (UC Berkeley) have recently carried out a study exploring the hydrodynamics of a quantum Heisenberg spin-1/2 chain. Their paper, published in Nature Physics, shows that the spin dynamics of a 1D Heisenberg antiferromagnet (i.e., KCuF3) could be effectively described by a dynamical exponent aligned with the so-called Kardar-Parisi-Zhang universality class.

“Joel Moore and I have known each other for many years and we both have an interest in quantum magnets as a place where we can explore and test new ideas in physics; my interests are experimental and Joel’s are theoretical,” Alan Tennant, one of the researchers who carried out the study, told Phys.org. “For a long time, we have both been interested in temperature in quantum systems, an area where a number of really new insights have come along recently, but we had not worked together on any projects.”

Apr 13, 2021

Topological insulator metamaterial with giant circular photogalvanic effect

Posted by in categories: biological, chemistry, food, nanotechnology, physics, space

Topological insulators have notable manifestations of electronic properties. The helicity-dependent photocurrents in such devices are underpinned by spin momentum-locking of surface Dirac electrons that are weak and easily overshadowed by bulk contributions. In a new report now published on Science Advances, X. Sun and a research team in photonic technologies, physics and photonic metamaterials in Singapore and the U.K. showed how the chiral response of materials could be enhanced via nanostructuring. The tight confinement of electromagnetic fields in the resonant nanostructures enhanced the photoexcitation of spin-polarized surface states of a topological insulator to allow an 11-fold increase of the circular photogalvanic effect and a previously unobserved photocurrent dichroism at room temperature. Using this method, Sun et al. controlled the spin transport in topological materials via structural design, a hitherto unrecognized ability of metamaterials. The work bridges the gap between nanophotonics and spin electronics to provide opportunities to develop polarization-sensitive photodetectors.

Chirality

Chirality is a ubiquitous and fascinating natural phenomenon in nature, describing the difference of an object from its mirror image. The process manifests in a variety of scales and forms from galaxies to nanotubes and from organic molecules to inorganic compounds. Chirality can be detected at the atomic and molecular level in fundamental sciences, including chemistry, biology and crystallography, as well as in practice, such as in the food and pharmaceutical industry. To detect chirality, scientists can use interactions with electromagnetic fields, although the process can be hindered by a large mismatch between the wavelength of light and the size of most molecules at nanoscale dimensions. Designer metamaterials with structural features comparable to the wavelength of light can provide an independent approach to devise optical properties on demand to enhance the light-matter interaction to create and enhance the optical chirality of metamaterials. In this work, Sun et al.

Apr 13, 2021

IoT, Industrial Devices Impacted

Posted by in categories: internet, robotics/AI

In real-world attacks, “a simple scenario… would have an attacker infiltrating a manufacturing network via an RCE on an exposed IoT device then causing a production line to stop by causing a DoS on an industrial controller,” Daniel dos Santos, research manager at Forescout Research Labs, said. “Similarly, the attacker could switch off the lights of a target company by leveraging a vulnerable building automation controller.”

Many of the Name: Wreck vulnerabilities stem from DNS implementations of a protocol feature called message compression. Message compression reduces the size of DNS messages, due to DNS response packets often including the same domain name. This compression mechanism has been problematic to implement on products for 20 years, said researchers, causing issues on DNS servers, enterprise devices and, more recently, TCP/IP stacks. Forescout researchers disclosed three flaws relating to message compression during previous research into TCP/IP vulnerabilities (particularly the Ripple20 and AMNESIA:33 sets of flaws). Consequently, they hunted for other similar types of flaws in other protocol stacks.

As part of the ensuing Name: Wreck research, researchers found DNS message compression vulnerabilities in four popular TCP/IP stacks, including FreeBSD (version 12.1), IPnet (version VxWorks 6.6), NetX (version 6.0.1) and Nucleus Net (version 4.3). The most critical flaws exist in FreeBSD, popular IT software used by high-performance servers in millions of IT networks, including major websites such as Netflix and Yahoo; and in Siemens’ Nucleus NET firmware, which has been used for decades by critical OT and Internet-of-Things (IoT) devices.

Apr 13, 2021

Microsoft Fixes Windows Zero Day Exploited in the Wild, Four More Exchange Flaws

Posted by in category: futurism

Microsoft has released patches for a Windows bug that is being exploited in the wild and for four new Exchange vulnerabilities.

Apr 13, 2021

Threat Groups Prey on Mobile With Evolving Malware, Tactics

Posted by in category: cybercrime/malcode

Up to 97 percent of organizations reported facing mobile threats that used multiple attack vectors during 2020, as cybercriminals continue to adopt new tactics to target mobile devices.

Apr 13, 2021

Preparing for AI-enabled cyberattacks

Posted by in categories: business, cybercrime/malcode, existential risks, information science, robotics/AI

MIT Technology Review Insights, in association with AI cybersecurity company Darktrace, surveyed more than 300 C-level executives, directors, and managers worldwide to understand how they’re addressing the cyberthreats they’re up against—and how to use AI to help fight against them.


Cyberattacks continue to grow in prevalence and sophistication. With the ability to disrupt business operations, wipe out critical data, and cause reputational damage, they pose an existential threat to businesses, critical services, and infrastructure. Today’s new wave of attacks is outsmarting and outpacing humans, and even starting to incorporate artificial intelligence (AI). What’s known as “offensive AI” will enable cybercriminals to direct targeted attacks at unprecedented speed and scale while flying under the radar of traditional, rule-based detection tools.

Some of the world’s largest and most trusted organizations have already fallen victim to damaging cyberattacks, undermining their ability to safeguard critical data. With offensive AI on the horizon, organizations need to adopt new defenses to fight back: the battle of algorithms has begun.

Continue reading “Preparing for AI-enabled cyberattacks” »

Apr 13, 2021

BPA-like chemicals likely causing “alarming” damage to brain cells

Posted by in categories: biotech/medical, chemistry, food, health, neuroscience

Controversy has shrouded the once-common plasticizer BPA since studies started to highlight its links to a whole range of adverse health effects in humans, but recent research has also shown that its substitutes mightn’t be all that safe either. A new study has investigated how these compounds impact nerve cells in the adult brain, with the authors finding that they likely permanently disrupt signal transmission, and also interfere with neural circuits involved in perception.

BPA, or bisphenol A, is a chemical that has been commonly used in food, beverage and other types of packaging for decades, but experts have grown increasingly concerned that it can leech into these consumables and impact human health in ways ranging from endocrine dysfunction to cancer. This came on the back of scientific studies revealing such links dating back to the 1990s, which in turn saw the rise of “BPA-free” plastics as a safer alternative.

One of those alternatives is bisphenol S (BPS), and while it allows plastic manufacturers to slap a BPA-free label on their packaging, more and more research is demonstrating that it mightn’t be much better for us. As just one example, a study last year showed through experiments on mice that just like BPA, BPS can alter the expression of genes in the placenta and likely fundamentally disrupt fetal brain development.

Apr 13, 2021

Broadcom moves its Symantec, CA software portfolios to Google Cloud

Posted by in category: futurism

Broadcom will deliver its enterprise software portfolio starting with Symantec via Google Cloud. DevOps and the former CA Technologies applications will also move over.

Apr 13, 2021

Introducing Microsoft Mesh

Posted by in category: augmented reality

https://youtu.be/Jd2GK0qDtRg

Microsoft Mesh enables presence and shared experiences from anywhere – on any device – through mixed reality applications.

Mesh allows for connections with new depth and dimension. As digital intelligence comes to the real world, we’re now able to see, share, and collaborate on content that persists. This common understanding ignites ideas, sparks creativity, and forms powerful bonds.

Continue reading “Introducing Microsoft Mesh” »

Apr 13, 2021

Military programs aiming to end pandemics forever

Posted by in categories: biotech/medical, military

Bill Whitaker reports on the Pentagon projects that helped combat COVID-19 and may help end pandemics forever.