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Nov 27, 2021

In the quantum realm, not even time flows as you might expect

Posted by in category: quantum physics

A team of physicists at the Universities of Bristol, Vienna, the Balearic Islands and the Institute for Quantum Optics and Quantum Information (IQOQI-Vienna) has shown how quantum systems can simultaneously evolve along two opposite time arrows—both forward and backward in time.

The study, published in the latest issue of Communications Physics, necessitates a rethink of how the flow of time is understood and represented in contexts where quantum laws play a crucial role.

For centuries, philosophers and physicists have been pondering the existence of time. Yet, in the , our experience seems to extinguish any doubt that time exists and goes on. Indeed, in nature, processes tend to evolve spontaneously from states with less disorder to states with more disorder, and this propensity can be used to identify an arrow of time. In physics, this is described in terms of ‘entropy’, which is the physical quantity defining the amount of disorder in a system.

Nov 27, 2021

Quantum superposition of thermodynamic evolutions with opposing time’s arrows

Posted by in categories: particle physics, quantum physics

Taking a gas enclosed in a vessel as a pictorial example, the aforementioned state can be constructed by entangling the position of the piston with a further auxiliary quantum system, thereby establishing a quantum superposition of the following two processes: (i) a process wherein the gas particles are initially in thermal equilibrium confined in one half of the vessel by a piston, and the piston is pulled outwards, and (ii) the reverse process, in which the piston is pushed towards the gas, starting from an initial state where the gas occupies the entire vessel in thermal equilibrium.

We will now measure the work of the system undergoing the above-mentioned superposition of forward and time-reversal dynamics. In order to implement such a measurement, we formally construct a procedure described by a set of measurement operators forming a completely positive and trace-preserving (CPTP) map. In this regard, we will refer to a standard TPM procedure to measure work in quantum thermodynamic processes13. Implementations of the TPM in quantum setups25,26,27,28,29, as well as suitable extensions30,31,32,33, have recently received increasing attention. Our procedure can be seen as a generalisation of the TPM scheme to situations where different thermodynamic processes are allowed to be superposed, and can consequently interfere.

In the TPM scheme, work is defined as the energy difference between the initial and final states of the system, which are measured through ideal projective measurements of the system Hamiltonian implemented before and after the thermodynamic process associated with the protocol Λ34,35. This measurement scheme can be performed, individually, both for the forward and the time-reversal processes, enabling the construction of the work probability distributions P (W) and \(\tilde{P}(W)\) 0, respectively.

Nov 27, 2021

A 3D ink made of living cells for creating living structures

Posted by in categories: bioengineering, biotech/medical, chemistry

A team of researchers from Harvard University and Brigham and Women’s Hospital, Harvard Medical School, has developed a type of living ink that can be used to print living materials. In their paper published in the journal Nature Communications, the group describes how they made their ink and possible uses for it.

For several years, microbial engineers have been working to develop a means to create living materials for use in a wide variety of applications such as medical devices. But getting such materials to conform to desired 3D structures has proven to be a daunting task. In this new effort, the researchers have taken a new approach to tackling the problem—engineering Escherichia coli to produce a product that can be used as the basis for an ink for use in a 3D printer.

The work began by bioengineering the bacteria to produce living nanofibers. The researchers then bundled the fibers and added other ingredients to produce a type of living ink that could be used in a conventional 3D printer. Once they found the concept viable, the team bioengineered other microbes to produce other types of living fibers or materials and added them to the ink. They then used the ink to print 3D objects that had living components. One was a material that secreted azurin—an anticancer drug—when stimulated by certain chemicals. Another was a material that sequestered Bisphenol A (a toxin that has found its way into the environment) without assistance from other chemicals or devices.

Nov 27, 2021

A deep learning method to automatically enhance dog animations

Posted by in category: robotics/AI

Researchers at Trinity College Dublin and University of Bath have recently developed a model based on deep neural networks that could help to improve the quality of animations containing quadruped animals, such as dogs. The framework they created was presented at the MIG (Motion, Interaction & Games) 2021 conference, an event where researchers present some of the latest technologies for producing high-quality animations and videogames.

“We were interested in working with non-human data,” Donal Egan, one of the researchers who carried out the study, told TechXplore. “We chose for practicality reasons, as they are probably the easiest animal to obtain data for.”

Creating good quality animations of dogs and other animals is a challenging task. This is mainly because these animals move in complex ways and have unique gaits with specific footfall patterns. Egan and his colleagues wanted to create a framework that could simplify the creation of quadruped animations, producing more convincing content for both animated videos and videogames.

Nov 27, 2021

Akon Announces Launch Of AKOIN Cryptocurrency Mastercard

Posted by in categories: bitcoin, cryptocurrencies, economics

Back in April, it was reported that Akon planned to build a futuristic “Akon City” in Uganda. Along with Akon City, Akon launched AKOIN, his very own cryptocurrency.

According to the AKOIN website, which includes Akon City details and explains how it fits into the “I’m So Paid” singer’s efforts to bring resources and technological opportunities to Africa, AKOIN is “a cryptocurrency powered by a blockchain based eco-system of tools and services designed for entrepreneurs in the rising economies of Africa.”

Nov 27, 2021

Tabletop accelerator shoots cheap antimatter bullets

Posted by in category: futurism

Circa 2013


A device just a few square metres in size can churn out bursts of energetic positrons that rival ones made by huge accelerators.

Nov 27, 2021

Doing photon upconversion a solid: Crystals that convert light to more useful wavelengths

Posted by in categories: chemistry, solar power, sustainability

Solid-solution organic crystals have been brought into the quest for superior photon upconversion materials, which transform presently wasted long-wavelength light into more useful shorter wavelength light. Scientists from Tokyo Institute of Technology have revisited a materials approach previously deemed lackluster—using a molecule originally developed for organic LEDs—and have achieved outstanding performance and efficiency. Their findings pave the way for many novel photonic technologies, such as better solar cells and photocatalysts for hydrogen and hydrocarbon productions.

Light is a powerful source of energy that can, if leveraged correctly, be used to drive stubborn chemical reactions, generate electricity, and run optoelectronic devices. However, in most applications, not all the wavelengths of can be used. This is because the energy that each photon carries is inversely proportional to its wavelength, and chemical and are triggered by light only when the energy provided by individual photons exceeds a certain threshold.

This means that devices like solar cells cannot benefit from all the color contained in sunlight, as it comprises a mixture of photons with both high and low energies. Scientists worldwide are actively exploring materials to realize upconversion (PUC), by which photons with lower energies (longer wavelengths) are captured and re-emitted as photons with higher energies (shorter wavelengths). One promising way to realize this is through triplet-triplet annihilation (TTA). This process requires the combination of a sensitizer material and an annihilator material. The sensitizer absorbs low energy photons (long-wavelength light) and transfers its excited energy to the annihilator, which emits higher photons (light of shorter wavelength) as a result of TTA.

Nov 27, 2021

ESA’s Solar Orbiter Spacecraft Is Skimming Earth for a Gravity Assist — And It’s One of the Riskiest Planetary Flybys Ever

Posted by in categories: energy, satellites

The chance that ESA’s Solar Orbiter spacecraft will encounter space debris during its upcoming Earth flyby is very, very low. However, the risk is not zero and is greater than any other flyby ESA has performed. That there is this risk at all highlights the mess we’ve made of space – and why we need to take action to clean up after ourselves.

On November 27, after a year and eight months flying through the inner Solar System, Solar Orbiter will swing by home to ‘drop off’ some extra energy. This will line the spacecraft up for its next six flybys of Venus.

Continue reading “ESA’s Solar Orbiter Spacecraft Is Skimming Earth for a Gravity Assist — And It’s One of the Riskiest Planetary Flybys Ever” »

Nov 27, 2021

Red light therapy could improve eyesight that has declined due to age

Posted by in category: biotech/medical

Exposure to deep red or near-infrared light can improve the function of the eye’s mitochondria, the powerhouses in cells, resulting in slight but lasting improvement to declining eyesight.

Nov 27, 2021

Upcoming Moon missions spur the search for new spacesuits

Posted by in category: space

NASA has asked the private sector to design new spacesuits that can be used on the Moon.