Monthly Archives: April 2023

Predicted over a century ago as monstrous concentrations of mass that torture the fabric of the Universe into traps of light and information, black holes are now established as objects of fact.

But might every distortion of light we now come across be a certified concentration of infinite density, or should we leave room for the possibility that other exotic breeds of cosmic oddity might look uncannily like a hole in space as well?

Using mathematical modeling preserved for string theory, a trio of physicists from Johns Hopkins University in the US found some objects that look like black holes from afar might be something else entirely up close: a new type of hypothetical exotic star called a topological soliton.

Given string theory is a hypothesis begging for a means to be tested, these strange objects exist only on paper, floating about in the realm of pure mathematics. At least, as far as we know. But even as a theoretical construct, they could help us one day distinguish the true black holes from impostors.

"How would you tell when you don't have a black hole? We don't have a good way to test that," says physicist Ibrahima Bah. "Studying hypothetical objects like topological solitons will help us figure that out."

Black holes are arguably the most mysterious known objects in the Universe. Heck, we didn't even have concrete confirmation of their existence until the first detection of gravitational waves in 2015, less than 10 years ago. That's because black holes are so dense that their gravity warps the space-time around them to such a degree that, within a certain distance known as the event horizon, nothing in the Universe is fast enough to achieve escape velocity. Not even light in a vacuum.

This means that black holes emit no light we can currently detect, making them, well, invisible; and, since light is the main tool in our kit for understanding the Universe, we can really only learn about them by studying the space around them.

The black hole itself is mathematically described as a one-dimensional point of infinite density something which itself doesn't really equate anything meaningful in physics.

But we can also imagine other bizarre manifestations of physics behaving in a similar way. One example is boson stars, hypothetical objects that are transparent and therefore invisible, just like black holes.

Now, the small group led by physicist Pierre Heidmann has found that topological solitons represent another. These are sort of gravitational kinks in four-dimensional space-time predicted by string theory, in which the smallest elements of the Universe are not pixel-like points, but tiny vibrating strings.

From a distance, the area surrounding these kinks doesn't stand out as all that unusual. Up close, however, the topology of space is heavily distorted.

The team constructed their topological soliton mathematically, and then plugged their equations into simulations to see how it would behave. They overlaid the simulations over real pictures of space to get the most accurate understanding of how their construct would behave.

From a distance, the topological soliton looked exactly like a black hole, with light appearing to be swallowed.

At closer proximity, however, the topological soliton got weird. It didn't capture light as a black hole would at all, but scrambled it and re-emitted it.

"Light is strongly bent, but instead of being absorbed like it would in a black hole, it scatters in funky motions until at one point it comes back to you in a chaotic manner," Heidmann says. "You don't see a dark spot. You see a lot of blur, which means light is orbiting like crazy around this weird object."

String theory is an attempt to resolve a long and vexing tension in physics: between quantum mechanics, which describes how things behave on very small scales, and general relativity, which describes the larger scales. Quantum mechanics breaks down on relativity scales, and vice versa, which bothers physicists no end, because they should be able to play together nicely.

A unified theory of the two, what we call quantum gravity, has proven elusive. The topological soliton is the first string-theory based object that corresponds to the behavior of a black hole, demonstrating that quantum gravity objects can be used to describe real-world physics.

"These are the first simulations of astrophysically relevant string theory objects, since we can actually characterize the differences between a topological soliton and a black hole as if an observer was seeing them in the sky," Heidmann explains.

We don't expect to see them in the sky, obviously, but probing the possibilities could help scientists better understand the tension between quantum mechanics and general relativity, in the hope of one day bringing us to a resolution.

"It's the start of a wonderful research program," Bah says. "We hope in the future to be able to genuinely propose new types of ultracompact stars consisting of new kinds of matter from quantum gravity."

The research has been accepted in Physical Review D.

See the original post:

This String Theory "Star" Looks And Acts Exactly Like a Black Hole - ScienceAlert

This article has been reviewed according to ScienceX's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility:

fact-checked

peer-reviewed publication

trusted source

proofread

For two decades, it was believed that a possible quantum spin liquid was discovered in a synthetically produced material. In this case, it would not follow the laws of classical physics even on a macroscopic level, but rather those of the quantum world. There is great hope in these materials: they would be suitable for applications in quantum entangled information transmission (quantum cryptography) or even quantum computation.

Now, however, researchers from TU Wien and Toho University in Japan have shown that the promising material, -(BEDT-TTF)2Cu2(CN)3, is not the predicted quantum spin liquid, but a material that can be described using known concepts.

In their recent publication in the journal Nature Communications, the researchers report how they investigated the mysterious quantum state by measuring the electrical resistance in -(BEDT-TTF)2Cu2(CN)3 as a function of temperature and pressure. In 2021, Andrej Pustogow from the Institute of Solid State Physics at TU Wien has already investigated the magnetic properties of this material.

"Phase diagrams are the language of physics," says Pustogow, leading author of the current study. If you understand this language, a quick glance at the diagram shows how the properties of a material change depending on temperature and pressure. Water, for example, becomes solid at a temperature of 0C and gaseous at 100C. If you now change the pressure, for example by heating water in a pressure cooker, the boiling point increases to over 100C.

In order to now find out how the supposed quantum spin liquidi.e., a liquid in which the spins of the electrons can rotate freely and are quantum entangledbehaves under pressure, the research team carried out systematic resistance measurements. "The special thing is that the very shape of the phase boundary gives deep insights into the physics of magnetic quantum fluctuations, which actually can't be measured with electrical resistance per se," says Pustogow. This was only made possible by a method that is unique worldwide, which the Japanese partners used to study the material. "So we make the impossible possible and follow the entropy footprints of the magnetic moments and thus gain new insights into a supposed quantum spin fluid," continues Pustogow. Prof. Andrej Pustogow. Credit: Vienna University of Technology

The researchers also found that the phase diagram of -(BEDT-TTF)2Cu2(CN)3 strongly resembles that of helium-3. Already back in the 1950s a Soviet researcher predicted that helium-3 behaves differently from conventional materials, turning from solid to liquid rather than from liquid to solid at low temperatures (of less than 0.3 Kelvin). Exactly the same effect occurs with electrons in solids when they freeze upon increasing temperature from a metallic state (mobile electrons) to a Mott insulator, in which the electrons are firmly bound to the atom and do not move.

This "Pomeranchuk effect," named after the researcher who predicted it, was also observed by the international research team in -(BEDT-TTF)2Cu2(CN)3: At higher temperatures, the material initially shows insulating behavior with rigid electrons that melt into a liquid (metal) when it cools. Below 6 Kelvin, however, the electrons freeze again and lose their magnetic moments as well.

"Although -(BEDT-TTF)2Cu2(CN)3 itself is not a quantum spin liquid, our research provides important clues for further research into these materials. For example, our experiments help to better understand the mechanism of magnetoelastic coupling. If we succeed in controlling this effect, we may also be able to eventually realize a quantum spin liquid," Pustogow says.

More information: A. Pustogow et al, Chasing the spin gap through the phase diagram of a frustrated Mott insulator, Nature Communications (2023). DOI: 10.1038/s41467-023-37491-z

Journal information: Nature Communications

More here:

The quantum spin liquid that isn't one - Phys.org

Starting out his career as a stage actor, it was only in 2012 when South Korean actor Park Hae-soo got offered his first screen role in the TV series God of War. The actor was struggling to make a name for himself as he had been starring in minor supporting roles in different movies and TV shows here and there. What finally brought him recognition was his role in an extremely popular Korean series, Prison Playbook. This show gave Park the jump-start he needed.

Now, we all know him as Cho Sang-woo in Netflixs Squid Game and as Berlin in the South Korean remake of Money Heist. That said, Park has recently signed with a U.S. talent agency, so we can definitely expect to hear more from him. In the meantime, here are the actors best movies and TV shows so far.

Park's first-ever lead role, Prison Playbook is a South Korean drama revolving around the lives of different convicts in correctional facilities. Park plays the character of Kim Je-hyuk, a baseball player who gets a year of jail time after protecting his sister from an assault. The series quickly became a commercial hit and one of the highest-ranked k-dramas in South Korean cable history.

The show definitely needs more credit from public and international viewers, as its comedy and lightheartedness helps you relax after a stressful day. The slice of life concept makes you laugh, cry, and forget about your daily problems.

Related: Ha Seung Lees Best Movies and TV Shows, Ranked

Directed by Kim Do-hoon, Chimera is a k-drama starring Park, Lee Hee-joon, and Claudia Kim in the leading roles. It follows these three leading characters as they dig through different records from the past thirty years to find a culprit nicknamed the Chimera. Park plays the 35-year-old Cha Jae-hwan, who is a perfectionist homicide detective. The use of Greek mythology to walk us through the case makes the story unique, as well as really creative and different. As a viewer, you feel emotionally connected to it to the mystery and crime. It should definitely be more popular than it is now.

Inspired by a classic Joseon legend, The Legend of the Blue Sea is a South Korean series telling the love story between a con-artist, Heo Joon-jae, and a mermaid, Shim Cheong, who travels across the ocean to find him. Park does very well playing determined detectives, and this k-drama is no different.

We see the actor play a recurring role of Hong Dong-pyo, a modern day detective who is investigating Joon-jae's scams, but later sides with him. Even if you don't particularly enjoy watching series with multiple one-hour-plus-long episodes, this one will change your mind. It makes you feel different types of emotions, from happiness to anger to confusion.

Based on Mai Jia's 2007 novel, Feng Sheng, Phantom is a 2023 spy action film set in 1933 during the Japanese colonization of Korea. When an attempt to assassinate a Japanese official fails, the plot focuses on different suspects and their attempts to clear the suspicions shed on them. Park plays one of the Japanese officials named Kaito, who's in charge of the investigation to catch the anti-Japanese spy.

It's easy to love every little bit of the movie, from the cinematography to the soundtrack. Most of its plot revolves around a closed setting despite the large scale resistance movement, which isn't necessarily a bad thing in this case.

Starring Park, Seo Yea-ji, and Kim Sang-ho in the lead roles, By Quantum Physics A Nightlife Venture is a South Korean crime film. The story follows a club owner Lee Chan-woo, the club manager Seong Eun-yeong and a police reporter Park ki-hum. Park plays the character of Lee, a nightclub promoter, who gets involved in a fight against organized crime and corruption.

Although the story gets a little hard to follow, it's worth checking out if you're a fan of the leading stars. Park gets a chance to showcase his ability to play a more funny nonsense chatter character that's way different from his serious roles.

The Pirates is a South Korean period adventure film that follows a group of pirates and bandits who embark on a journey to catch a big whale that's swallowed their new Joseon Dynasty emperor. Park doesn't play the leading character in this one, but instead plays a supporting character named Hwang Joong-geun.

The pirates versus thieves dynamic combines comedy, action and fantasy and makes it all magically work. The humor works really well and the action sequences are nicely choreographed. All you need to do is allow yourself to enjoy the entertainment.

Related: Best Lee Dong-wook Movies and TV Shows, Ranked

Directed by Na Hyeon, Yaksha: Ruthless Operations is a spy action film, starring Sol Kyung-gu and Park Hae-soo in leading roles. The plot takes place in Chinese Shenyang, and revolves around a leader of an espionage agency's black ops team and a prosecutor who gets moved to a lower rank in the agency. Park plays the prosecutor Han Ji-hoon, who believes that justice should be served rightfully through law. If you want to spend your time with an action-packed spy thriller, then this is a very good first choice.

Based on true events, Narco-Saints also known as Suriname, is a Netflix show about an ordinary entrepreneur who's forced to join a mission to capture drug lords in South America. Park plays the character of Choi Chang-ho, the leader of National Intelligence Service's Branch in the Americas.

The series serves as a "play next" to Narcos and Narcos: Mexico. The cast they picked for the show has done an amazing job at always having you wait what happens next. It can easily be described as a next sensational hit from the South Korean industry.

The first South Korean movie having been screened in the Berlinale Special section, Time to Hunt is a dystopian action thriller. Set in a dystopian South Korea, it follows a group of friends who plan a huge heist, but instead find themselves hunted by a mysterious assassin. Park plays one of the friends and one of the main characters called Han.

Despite the movie's long run-time, the story doesn't get boring as the script wasn't meant to be deep and meaningful. Han's character feels very much like a South Korean John Wick and would easily be enjoyable to watch in a standalone movie.

Despite the mixed reactions this South Korean remake has received, you have to admit that Money Heist: Korea: Joint Economic Area has definitely brought something new to the story. As a second series in the Money Heist franchise, the show follows a group of thieves with different personalities led by an intelligent man nicknamed the Professor, as they overtake the mint of a unified Korea. Park plays the character of Berlin, who is a 41-year-old North Korean former prisoner of the Kaechon concentration camp. Due to his trauma, he's quick to resort to violence and threats.

We can't go without mentioning Squid Game when talking about Park Hae-soo. The survival drama took the world by storm upon its 2021 release on Netflix. It became Netflix's most-watched series, amassing 1.65 billion viewing hours during its first four weeks of launch. In the show, 456 players risk their lives playing children's games to win a huge financial prize. Cho Sang-woo is Park's complex character, who joins the game to escape the police. The extreme violence mixed with humor makes it hard to watch at times, but it shows just how far people are willing to go when they have nothing to lose.

Link:

Park Hae-soo's Best Movies and TV Shows, Ranked - MovieWeb

From black holes and Schrodingers cat to machines capable of teleporting information, quantum computings road from sci-fi to investable opportunity may be early stage but its potential to affect seismic change in products such as thematic ETFs should not be underestimated.

Physicist Richard Feynman famously said if you think you understand quantum mechanics, then you do not. This rings true for the study of subatomic behaviour that defies the laws of physics but even more so when trying to understand the machines harnessing this behaviour to revolutionise computing.

Exponentially scaling the processing power of classical computers will soon be impossible, with transistors in silicon chips already a thousandth of the diameter of a red blood cell. However, these computers rely on binary digits called bits ones and zeros as their units of information, whereas quantum devices rely on qubits which can be represented as ones, zeros or through superposition the ability to be in multiple things at once they can appear as a mix of the two simultaneously.

This article first appeared in ETF Insider, ETF Stream's monthly ETF magazine for professional investors in Europe. To read the full article,click here.

Excerpt from:

How quantum computing will disrupt thematic ETFs - ETF Stream

The 102-year-old Indian-American scientists work in statistics now propels the field of science right from data analytics to analysing data from Large Hadron Collider, the worlds most powerful accelerator that found the elusive God particle or the Higgs Boson a decade ago.

In fact when a cardiologist had a problem constructing the shape of the human left ventricle from a pair of X-ray projection images taken from two perpendicular camera sets it led to his extensive work on shape analysis.

When he was at Cambridge University, he was presented with the Jebel Moya problem. Skeletons from an ancient grave in Africa were brought back to the university and Rao analysed their measurements to determine their lives and relationship with neighbours. Thats when he introduced the concept of quadratic entropy, a general measure of diversity or non-homogeneity in a population.

For decades, his papers and works have helped scientists estimate results of experiments starting right from basic sciences like physics, chemistry and biology to artificial intelligence (AI), radar systems and many more that are to come.

After completing his high school education in Visakhapatnam, he obtained his Masters Degree in Mathematics from Andhra University in 1940. Later, he joined a masters programme at the Calcutta University in statistics which was newly instituted. Needless to say, he received the highest rank possible and a gold medal too.

Two years before India got its independence, he published a paper where he demonstrated three fundamental results Cramer-Rao lower bound, the Rao-Blackwell Theorem; and introduced differential geometric methods in statistical estimation. His third result formed the basis for a new interdisciplinary field - information geometry.

He went to Cambridge for a project and came back to work at the Indian Statistical Institute in the late 1940s. At the institute, he rose to the ranks of a director and quit in 1976. In 1978, he moved to the US as a university professor after retiring, and continues to the professor emeritus of statistics at Penn State.

So, to answer the question posed at the start of this piece thanks in large part to the efforts of Rao, statistics is used in everything from computer science, quantum physics, linguistics and sociology to economics.

Continued here:

Pride of India: Statistician CR Raos influence is widespread The Higgs Boson, shape of the heart, archaeolo - Business Insider India

The contemporary computer processor at only half the size of a penny possesses the extraordinary capacity to carry out 11 trillion operations per second, with the assistance of an impressive assembly of 16 billion transistors.[1] This feat starkly contrasts the early days of transistor-based machines, such as the Manchester Transistor Computer, which had an estimated 100,000 operations per second, using 92 transistors and having a dimension of a large refrigerator. For comparison, while the Manchester Transistor Computer could take several seconds or minutes to calculate the sum of two large numbers, the Apple M1 chip can calculate it almost instantly. Such a rapid acceleration of processing capabilities and device miniaturization is attributable to the empirical observation known as Moores Law, named after the late Gordon Moore, the co-founder of Intel. Moores Law posits that the number of transistors integrated into a circuit is poised to double approximately every two years.[2]

In their development, these powerful processors have paved the way for advancements in diverse domains, including the disruptive field of artificial intelligence (AI). Nevertheless, as we confront the boundaries of Moores Law due to the physical limits of transistor miniaturization,[3] the horizons of the field of computing are extended into the enigmatic sphere of quantum physics the branch of physics that studies the behavior of matter and energy at the atomic and subatomic scales. It is within this realm that the prospect of quantum computing arises, offering immense potential for exponential growth in computational performance and speed, thereby heralding a transformative era in AI.

In this article, we scrutinize the captivating universe of quantum computing and its prospective implications on the development of AI and examine the legal measures adopted by leading tech companies to protect their innovations within this rapidly advancing field, particularly through patent law.

Qubits: The Building Blocks of Quantum Computing

In classical computing, the storage and computation of information are entrusted to binary bits, which assume either a 0 or 1 value. For example, a classical computer can have a specialized storage device called a register that can store a specific number at a time using bits. Each bit is like a slot that can be either empty (0) or occupied (1), and together they can represent numbers, such as the number 2 (with a binary representation of 010). In contrast, quantum computing harnesses the potential of quantum bits (infinitesimal particles, such as electrons or photons, defined by their respective quantum properties, including spin or polarization), commonly referred to as qubits.

Distinct from their classical counterparts, qubits can coexist in a superposition of states, signifying their capacity to represent both 0 and 1 simultaneously. This advantage means that, unlike bits with slots that are either empty or occupied, each qubit can be both empty and occupied at the same time, allowing each register to represent multiple numbers concurrently. While a bit register can only represent the number 2 (010), a qubit register can represent both the numbers 2 and 4 (010 and 100) simultaneously.

This superposition of states enables the parallel processing of information since multiple numbers in a qubit register can be processed at one time. For example, a classical computer may use two different bit registers to first add the number 2 to the number 4 (010 +100) and then add the number 4 to the number 1 (100+001), performing the calculations one after the other. In contrast, qubit registers, since they can hold multiple numbers at once, can perform both operationsadding the number 2 to the number 4 (010 + 100) and adding the number 4 to the number 1 (100 + 001)simultaneously.

Moreover, qubits employ the singular characteristics of entanglement and interference to execute intricate computations with a level of efficiency unattainable by classical computers. For instance, entanglement facilitates instant communication and coordination, which increases computational efficiency. At the same time, interference involves performing calculations on multiple possibilities at once and adjusting probability amplitudes to guide the quantum system toward the optimal solution. Collectively, these attributes equip quantum computers with the ability to confront challenges that would otherwise remain insurmountable for conventional computing systems, thereby radically disrupting the field of computing and every field that depends on it.

Quantum Computing

Quantum computing embodies a transformative leap for AI, providing the capacity to process large data sets and complex algorithms at unprecedented speeds. This transformative technology has far-reaching implications in fields like cryptography,[4] drug discovery,[5] financial modeling,[6] and numerous other disciplines, as it offers unparalleled computational power and efficacy. For example, a classical computer using a General Number Field Sieve (GNFS) algorithm might take several months or even years to factorize a 2048-bit number. In contrast, a quantum computer using Shors algorithm (a quantum algorithm) could potentially accomplish this task in a matter of hours or days. This capability can be used to break the widely used RSA public key encryption system, which would take conventional computers tens or hundreds of millions of years to break, jeopardizing the security of encrypted data, communications, and transactions across industries such as finance, healthcare, and government. Leveraging the unique properties of qubitsincluding superposition, entanglement, and interference quantum computers are equipped to process vast amounts of information in parallel. This capability enables them to address intricate problems and undertake calculations at velocities that, in certain but not all cases,[7] surpass those of classical computers by orders of magnitude.

The augmented computational capacity of quantum computing is promising to significantly disrupt various AI domains, encompassing quantum machine learning, natural language processing (NLP), and optimization quandaries. For instance, quantum algorithms can expedite the training of machine learning models by processing extensive datasets with greater efficiency, enhancing performance, and accelerating model development. Furthermore, quantum-boosted natural language processing algorithms may yield more precise language translation, sentiment analysis, and information extraction, fundamentally altering how we engage with technology.

Patent Applications Related to Quantum Computers

While quantum computers remain in their nascent phase, to date, the United States Patent and Trademark Office has received more than 6,000 applications directed to quantum computers, with over 1,800 applications being granted a United States patent. Among these applications and patents, IBM emerges as the preeminent leader, trailed closely by various companies, including Microsoft, Google, and Intel, which are recognized as significant contributors to the field of AI. For instance, Microsoft is a major investor in OpenAI (the developer of ChatGPT) and has developed Azure AI (a suite of AI services and tools for implementing AI into applications or services) and is integrating ChatGPT into various Microsoft products like Bing and Microsoft 365 Copilot. Similarly, Google has created AI breakthroughs such as AlphaGo (AI that defeated the world champion of the board game Go), hardware like tensor processing units (TPUs) (for accelerating machine learning and deep learning tasks), and has released its own chatbot called Bard (also known as LaMDA).

Patents Covering Quantum Computing

The domain of quantum computing is progressing at a remarkable pace, as current research seeks to refine hardware, create error correction methodologies, and investigate novel algorithms and applications. IBM and Microsoft stand at the forefront of this R&D landscape in quantum computing. Both enterprises have strategically harnessed their research findings to secure early patents encompassing quantum computers. Notwithstanding, this initial phase may merely represent the inception of a competitive endeavor to obtain patents in this rapidly evolving field. A few noteworthy and recent United States patents that have been granted thus far include:

Conclusion

Quantum computing signifies a monumental leap forward for AI, offering unparalleled computational strength and efficiency. As we approach the limits of Moores Law, the future of AI is contingent upon harnessing qubits distinctive properties, such as superposition, entanglement, and interference. The cultivation of quantum machine learning, along with its applications in an array of AI domains, including advanced machine learning, NLP, and optimization, portends a revolution in how we address complex challenges and engage with technology.

Prominent tech companies like IBM and Microsoft have demonstrated their commitment to this burgeoning field through investments and the construction of patent portfolios that encompass this technology. The evident significance of quantum computing in shaping the future of AI suggests that we may be witnessing the onset of a competitive patent race within the sphere of quantum computing.

Read this article:

The Quantum Frontier: Disrupting AI and Igniting a Patent Race - Lexology

This article has been reviewed according to ScienceX's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility:

fact-checked

peer-reviewed publication

trusted source

proofread

Digital displays comprising organic materials have brought about a new era in consumer electronics, helping to mass produce brighter screens that hold numerous advantages over those made of regular crystalline materials. These organic light-emitting diodes, or OLEDs, can, for example, enable the manufacture of foldable phones that double their screen size when opened.

Yet even the most advanced OLED displays in production today waste about half of the light they emita shortfall that had seemed unavoidable because it stems from the physics of light. A new study, led by a Weizmann Institute of Science researcher, Prof. Binghai Yan of the Condensed Matter Physics Department, may lead to a change in the way future devices light up their OLED screens.

In this collaborative study, Yan and colleagues discovered a new method for controlling a key property of light. This technique, which involves new material and device designs, paves the way to making screens that are twice as brightor twice as energy efficientas the ones currently on the market. It may also lead to far faster data transmission capabilities than those existing today, applications that showcase the huge potential of next-generation organic semiconductors.

To understand why state-of-the-art displays have a brightness cutoff, we must first consider the property of light known as handedness, or chirality, a term derived from the Greek word for "hand." Its meaning depends on the context. In physics, chirality refers to the self-rotation of particles in relation to their motion. When photons or electrons flow, they move in space, but they also spin. When these particles spin in the same direction in which they travel, as a bullet does, we call their chirality right-handed; when they spin against that direction, they have left-handed chirality.

In biology and chemistry, chirality refers to objects that are mirror images of each other, like two hands. For example, DNA, proteins and most other naturally occurring organic molecules are termed right-handed. And there is considerable interplay between different types of chirality. For instance, the geometric chirality of molecules in an organic material determines the chirality of particles passing through them.

This is relevant to many display applications because these displays have a transparent outer layer made of a chiral material, which allows only one-handed lightsay, right-handedto pass in and out, blocking the entry of photons of the other chirality. It does this to neutralize incoming ambient light, whose chirality is mixed; if allowed to pass through, this light would lower the screen's contrast, making it difficult to view in daylight.

The one-handed transparent layer is essential for operating displays in bright light (try using your smartphone to navigate at high noon without it), but it's wasteful. When the diodes of modern screens emit lightwhich generally has a mixed chiralitytoward the screen's surface, half of this light's photons cannot reach the viewer, as their chirality doesn't match that of the transparent outer layer, which is fixed to neutralize ambient light.

But this may be about to change.

In the new study, Yan and his team proposed controlling the chirality of photons in ways previously deemed impossible. The proposal involves diodes that will predominantly emit light of one chiralitythe one that matches the chirality of the transparent outer layer. This can be achieved by creating diodes that simultaneously emit light in opposite directionsone facing forward, the other backwardand are outfitted with a back panel coated with a polymer containing a chiral organic material.

Half of the diode's light, the one that has a chirality matching the transparent layer, traverses this layer unhindered. But the remaining half is not lost. Rather, it bounces back and forth until hitting the back polymer panel of the diode, which flips its chirality. This polymer is engineered in such a way that the chirality information it contains is efficiently converted into the rotation of electrons, and then into the chirality of light, leading to strongly polarized light emission.

The study began with experimental results that initially appeared to be downright bizarre.

Dr. Li Wan, then a postdoctoral fellow at Linkping University in Sweden, found what we now know to be a method for controlling and amplifying the chirality of light in organic devices.

"These findings ran so counter to everything that was known in this field, other scientists had a hard time believing Wan's results. They said that something was probably wrong with his experiments," recalls Yan.

Wan and his Ph.D. supervisor, Prof. Alasdair Campbell, had shown that they could flip the chirality of an electron flow in their experimental installation by changing the polarity of the battery generating the electric current. Each time they flipped the polarity of the power supply, the chirality of the electron flow changed consistently. As they didn't change the materials, this finding was contrary to all textbook knowledge at the time.

Campbell was convinced they were on to something important, but he passed away in 2021, before Wan could back up his findings theoretically. Following Campbell's death, Wan sought out Yan, whose online lecture on chirality he had heard. In that lecture, Yan talked about his theory which, using concepts of quantum physics, explained how the chirality of a material determines the chirality of an electron flow.

Yan started analyzing Wan's experiments with Wan and two other scientists, Dr. Yizhou Liu of Weizmann's Condensed Matter Physics Department and Prof. Matthew J. Fuchter of Imperial College London. Yan had to extend his theory of chirality so that it would explain Wan's results, but Yan ended up showing that these findings were actually an inevitable outcome of his own theory. Moreover, the scientists found they could also control the chirality of light emitted by the electron flow by making sure that the photons fly out along the same trajectory as the flow, thus preserving their bullet-like spinning.

"We've revealed an intriguing unity between seemingly unrelated aspects of chirality: the structural geometry of a material, the handedness of an electron flow and finally, the handedness of light," Yan says, summing up the new study.

Apart from improving the efficiency of our screens, the study's findings could also be applied to achieving speedy data transmission. They could, for instance, be used to create optical switches that will work vastly faster than any mechanical ones, flipping the chirality of the photon flowsay, right-handed to denote 0, and left-handed, 1by switching the electric polarity.

And last but not least, yet another outcome of this research is that textbooks will need to be updated to account for Yan's theory of chirality.

The findings are published in the journal Nature Photonics.

More information: Li Wan et al, Anomalous circularly polarized light emission in organic light-emitting diodes caused by orbitalmomentum locking, Nature Photonics (2022). DOI: 10.1038/s41566-022-01113-9

Journal information: Nature Photonics

Continue reading here:

A collaborative study of a key property of light may help double screen luminescence - Phys.org

Taylor says that the course and Harnishs senior thesis, a play she wrote about the course material, This is Your Computer on Drugswhich she is also directing on April 29 and 30 at Columbiarepresent the culmination of their three-year collaborative relationship.

Harnish took her first class with Taylor, Philosophy of Religion, during the spring semester of her freshman year, after which she decided to become a religion major instead of the double major she had declared in philosophy and theater. This was also when COVID hit, right when Harnish was writing her midterm paper, so the course was completed over Zoom. She then enrolled in two more courses with Taylor during the fall 2020 semester, Theory and Recovering Place, because he had hinted at retirement. Both classes were conducted virtually.

It was the depths of the pandemic, and Harnish, who had returned to Indiana, where she grew up, was having a hard time. She was living alone in a government-subsidized apartment for artists in Indianapolis, working two jobs, taking 16 course credit hours, and trying to cope with life during COVID.

Come midterms, she emailed Taylor to alert him that she was planning on withdrawing from Columbia for the rest of the semester because of her difficulty managing everything. He offered to Zoom with her later that day.

He talked me into staying in school, said Harnish, and its a good thing he did, because my final project for Recovering Place was my first full-length play, The Foundation of Roses.

The 60-page script is a ghost story about her challenging childhood experiences, said Taylor. It was so remarkable that I nominated it for the Religion Departments Peter Awn Award, which is given annually to the most outstanding undergraduate paper or project in the department. My colleagues agreed with my assessment, and Alethea won the award in 2021.

Harnish has since written four more plays. One of them, Phantasmagoria, a one-person, autobiographical show, made its Off-Broadway debut in June 2022 when she performed it at the Downtown Urban Arts Festival, where it won second place for the Best Play Award. The work was about leaving her rural roots in Indiana to attend college in New York.

According to Harnish, she was the first person from her high school to get into an Ivy League university, and traveling halfway across the country to a big city was a culture shock. Meeting Taylor, who became a mentor, was very beneficial for her.

Over time, the relationship has morphed from a mentor-mentee one into something more reciprocal, said Harnish.

Taylor, who started teaching at Williams College in 1973, and arrived full-time at Columbia in 2007, said that early on he detected something very special about Alethea. It was not just her exceptional intelligence, interest, maturity, and determination, but also a rare imaginative creativity.

Once campus came back to life in fall 2021, at the start of Harnishs junior year, the two continued their conversations in person, and Harnish started sending Taylor examples of her writing. They met regularly during Taylors office hours to discuss her work. One day, she asked him what he was working on for his next book. Hegel and quantum mechanics, he said.

In one of those strange moments the theoretical physicist Wolfgang Pauli and the psychologist Carl Jung labeled synchronicity, said Taylor, Alethea said, Thats weird because I want to write and produce a play for my senior thesis about quantum physics and New Age spirituality.

Out of that convergence came the course theyre now co-teaching. They started by delving deeper into their shared interest in the material through reading and further discussion. Few people realize that personal computers, the Internet, the World Wide Web, and the Metaverse all trace their origins to hippies and the drug culture of the 1960s, said Taylor.

The more I thought about it, the clearer it became that this would be the perfect subject for my last course, he continued. My professional career spanned precisely the half-century from the 1960s to the present.

When Taylor asked her to co-teach the course, Harnish was initially terrified. We had spent almost two years in conversation by that point, and I knew that this would be the opportunity of a lifetime, she said. His insisting that he was also learning from me gave me the confidence to take on such a role.

Although Harnish has fully embraced her leadership role with the course this semester, she is not sure if she will pursue a career in higher education. Her immediate plans after graduation are to travel to Greece this summer with a Brooklyn-based theater company, providing administrative support for its apprentice program. She then wants to spend a year in New York, completing the applications for various playwriting fellowships and other writing programs.

Back in the classroom, the next time Hippie Physics meets, Harnish, dressed in a jean shirt, long, pleated skirt, and cowboy boots, leads the discussion on the assigned readings from The Book by Alan Watts and Zen Mind, Beginners Mind by Shunryu Suzuki. One of her touches has been to start every session spending a few moments listening to one of the eras classic rock songs, and then opening the floor to a parsing of the songs meaning. Todays selection is Led Zeppelins Stairway to Heaven.

After she stops the music, she says, What is the implication philosophically of there being a stairway to heaven for us? Were down here, and we have to get up there.

As he watches her effortlessly command the classroom, Taylor says, Strangely, the success of this course makes it both easier and more difficult for me to stop teaching. We hear much, perhaps too much, today about the problems with higher education, and especially with the humanities. But as I watch Alethea teach and her fellow undergraduates respond to her, I have hope for the future.

View original post here:

A Student Graduates, a Professor Retires, but They Will Stay in Touch - Columbia University

Erwin Schrdinger has been recognized as "the father of quantum mechanics," which deals with subatomic particles. At this level of scale, the normal laws of physics begin to break down, which is why quantum physics is now considered a separate school of thought from classical physics. Famously, Schrdinger once presented a thought experiment to illustrate a paradox inherent in the principle of quantum superposition, which provides that a system can exist in multiple states until its observation leads to the result: There is a cat inside a box, and the cat is both alive and dead until the box is opened, which is an interesting concept to make an allusion to on "Mrs. Davis."

It is hard to deny the similarities between Arthur Schroedinger on "Mrs. Davis" and the Nobel Prize-winning physicist. Besides the cat, Arthur claims to be a scientist himself, and both of them wear glasses. While Arthur is possibly a descendant of Schrdinger, who died in the 1960s, the zaniness of "Mrs. Davis" allows for the possibility that he may be Schrdinger himself in a different state. Either way, it will be interesting to see where the character fits into the equation and why he was missing for ten years.

Read the rest here:

Mrs. Davis Episode 1: The Crucial Clue To The Stranded Man's ... - Looper