Posted in physics
Physicists agree, one day it may be possible for a person to create a universe. It won’t happen tomorrow, but the idea is in the works. There’s already one problem with the idea: If a universe is created, physicists say they wouldn’t know how to communicate with it.
The word “network” has become part of our everyday language, in particular since the rise of online social networks. However, human interactions are not only aimed at sociability and fun. Criminals also interact with each other to plan their illicit actions, especially in organized crime.
Motivated by openly available data and publicly released judicial documents from a law-enforcement operation named “Operazione Infinito,” which was conducted in Lombardy between 2007 and 2009 to tackle the ‘Ndrangheta mafia, Bocconi Professor Daniele Durante and his co-authors have developed a new class of statistical models for grouping together criminals with similar connectivity patterns, thus shedding further light on the community structure of criminal organizations.
In fact, within most networks, not all the nodes—that here represent criminals—are connected to each other, and community structures typically arise. The simplest type of community structure is characterized by dense connections within each community, and sparser connections across different communities. This corresponds to the idea that each individual is more likely to connect with the individuals belonging to the same community.
A continuation of the enlightenment values that freed mankind of superstition.
Anders Sandberg discusses achieving a transhumanist utopia.
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Half of the universe is filled with expansionist alien civilizations, and it’s only a matter of time before they’ll reach us. OK, that sounded a little sensationalist. But it’s also the conclusion of a recent astrophysics paper. Let’s see how they figure this, and whether we should take it seriously.
IBM’s new quantum computer, Osprey, is more than triple the size of its previous record-breaking Eagle processor.
Summary: Using monoclonal antibodies instead of conventional immunosuppressant drugs preserves stem cells in mouse brains.
Source: University of Michigan.
A new approach to stem cell therapy that uses antibodies instead of traditional immunosuppressant drugs robustly preserves cells in mouse brains and has potential to fast-track trials in humans, a Michigan Medicine study suggests.
After several years of developing the theoretical ideas, University of Illinois Urbana-Champaign researchers have validated multiple novel predictions about the fundamental mechanism of transport of atoms and molecules (penetrants) in chemically complex molecular and polymer liquid matrices.
The study from Materials Science and Engineering (MatSE) Professor Ken Schweizer and Dr. Baicheng Mei, published recently in Proceedings of the National Academy of Sciences (PNAS), extended the theory and tested it against a large amount of experimental data. MatSE Associate Professor Chris Evans and graduate student Grant Sheridan collaborated on this research by providing additional experimental measurements.
“We developed an advanced, state-of-the art theory to predict how molecules move through complex media, especially in polymer liquids,” Schweizer said. “The theory abstracted what the important features are of the chemically complex molecules and of the polymeric medium that they’re moving through that control their rate of transport.”
Chirality is the breaking of reflection and inversion symmetries. Simply put, it is when an object’s mirror images cannot be superimposed over each other. A common example are your two hands—while mirror images of each other, they can never overlap. Chirality appears at all levels in nature and is ubiquitous.
In addition to static chirality, chirality can also occur due to dynamic motion including rotation. With this in mind, we can distinguish true and false chirality. A system is truly chiral if—when translating—space inversion does not equate to time reversal combined with a proper spatial rotation.
Phonons are quanta (or small packets) of energy associated with the vibration of atoms in a crystal lattice. Recently, phonons with chiral properties have been theorized and experimentally discovered in two-dimensional (2D) materials such as tungsten diselenide. The discovered chiral phonons are rotating—yet not propagating—atomic motions. But, truly chiral phonons would be atomic motions that are both rotating and propagating, and these have never been observed in three-dimensional (3D) bulk systems.
Vibrating tiny robots could revolutionize research.
Individual robots can work collectively as swarms to create major advances in everything from construction to surveillance, but microrobots’ small scale is ideal for drug delivery, disease diagnosis, and even surgeries.
Despite their potential, microrobots’ size often means they have limited sensing, communication, motility, and computation abilities, but new research from the Georgia Institute of Technology enhances their ability to collaborate efficiently. The work offers a new system to control swarms of 300 3-millimeter microbristle robots’ (microbots) ability to aggregate and disperse controllably without onboard sensing.
Organic photovoltaics, solar energy devices based on organic semiconductors, have so far achieved very promising results in experimental settings, both in terms of efficiency and stability. However, engineers have not yet devised reliable strategies to fabricate these devices on a large-scale at a reasonable cost.
Researchers at Wuhan University in China have recently identified an approach that could facilitate the rapid fabrication of photoactive layers for organic solar cells, without compromising the cells’ efficiency and stability. Their proposed strategy, introduced in a paper published in Nature Energy, is based on sequential deposition, a method often used to deposit organic semiconductors and perovskite films on substrates.
“To realize the commercialization of organic photovoltaics (OPVs), the golden triangle of power conversion efficiency (PCE), stability, and cost should be considered simultaneously,” Jie Min, one of the researchers who carried out the study, told TechXplore.
