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Aug 16, 2022

Team reports giant response of semiconductors to light

Posted by in categories: electronics, materials

In an example of the adage “everything old is new again,” MIT engineers report a new discovery in semiconductors, well-known materials that have been the focus of intense study for over 100 years thanks to their many applications in electronic devices.

The team found that these important materials not only become much stiffer in response to light, but the effect is reversible when the light is turned off. The engineers also explain what is happening at the atomic scale, and show how the effect can be tuned by making the materials in a certain way—introducing specific defects—and using different colors and intensities of light.

“We’re excited about these results because we’ve uncovered a new scientific direction in an otherwise very well-trod field. In addition, we found that the phenomenon may be present in many other compounds,” says Rafael Jaramillo, the Thomas Lord Associate Professor of Materials Science and Engineering at MIT and leader of the team.

Aug 16, 2022

A Relativistic Theory of Consciousness

Posted by in categories: mathematics, neuroscience, physics

In recent decades, the scientific study of consciousness has significantly increased our understanding of this elusive phenomenon. Yet, despite critical development in our understanding of the functional side of consciousness, we still lack a fundamental theory regarding its phenomenal aspect. There is an “explanatory gap” between our scientific knowledge of functional consciousness and its “subjective,” phenomenal aspects, referred to as the “hard problem” of consciousness. The phenomenal aspect of consciousness is the first-person answer to “what it’s like” question, and it has thus far proved recalcitrant to direct scientific investigation. Naturalistic dualists argue that it is composed of a primitive, private, non-reductive element of reality that is independent from the functional and physical aspects of consciousness. Illusionists, on the other hand, argue that it is merely a cognitive illusion, and that all that exists are ultimately physical, non-phenomenal properties. We contend that both the dualist and illusionist positions are flawed because they tacitly assume consciousness to be an absolute property that doesn’t depend on the observer. We develop a conceptual and a mathematical argument for a relativistic theory of consciousness in which a system either has or doesn’t have phenomenal consciousness with respect to some observer. Phenomenal consciousness is neither private nor delusional, just relativistic. In the frame of reference of the cognitive system, it will be observable (first-person perspective) and in other frame of reference it will not (third-person perspective). These two cognitive frames of reference are both correct, just as in the case of an observer that claims to be at rest while another will claim that the observer has constant velocity. Given that consciousness is a relativistic phenomenon, neither observer position can be privileged, as they both describe the same underlying reality. Based on relativistic phenomena in physics we developed a mathematical formalization for consciousness which bridges the explanatory gap and dissolves the hard problem. Given that the first-person cognitive frame of reference also offers legitimate observations on consciousness, we conclude by arguing that philosophers can usefully contribute to the science of consciousness by collaborating with neuroscientists to explore the neural basis of phenomenal structures.

As one of the most complex structures we know of nature, the brain poses a great challenge to us in understanding how higher functions like perception, cognition, and the self arise from it. One of its most baffling abilities is its capacity for conscious experience (van Gulick, 2014). Thomas Nagel (1974) suggests a now widely accepted definition of consciousness: a being is conscious just if there is “something that it is like” to be that creature, i.e., some subjective way the world seems or appears from the creature’s point of view. For example, if bats are conscious, that means there is something it is like for a bat to experience its world through its echolocational senses. On the other hand, under deep sleep (with no dreams) humans are unconscious because there is nothing it is like for humans to experience their world in that state.

In the last several decades, consciousness has transformed from an elusive metaphysical problem into an empirical research topic. Nevertheless, it remains a puzzling and thorny issue for science. At the heart of the problem lies the question of the brute phenomena that we experience from a first-person perspective—e.g., what it is like to feel redness, happiness, or a thought. These qualitative states, or qualia, compose much of the phenomenal side of consciousness. These qualia are arranged into spatial and temporal patterns and formal structures in phenomenal experience, called eidetic or transcendental structures1. For example, while qualia pick out how a specific note sounds, eidetic structures refer to the temporal form of the whole melody. Hence, our inventory of the elusive properties of phenomenal consciousness includes both qualia and eidetic structures.

Aug 16, 2022

Smart nanoparticle shows that intermittent fasting may protect the heart from damage during chemotherapy

Posted by in categories: biotech/medical, nanotechnology

Although chemotherapy can be a lifesaving treatment for patients with cancer, some of these medications can damage the heart. A team led by researchers at Massachusetts General Hospital (MGH) recently developed a nanoparticle probe that can detect an indicator of heart damage from chemotherapy.

Experiments with the probe also revealed that in mice with cancer, intermittent fasting before chemotherapy can prevent this damage indicator from arising, leading to preserved cardiac function and prolonged survival.

The study, which is published in Nature Biomedical Engineering, focused on autophagy—a process that cells use to remove unnecessary or dysfunctional components. A delicate balance exists between the protective and deleterious effects of this process: reduced levels of autophagy have been implicated in and other conditions; however, autophagy can also be a primary mechanism of cell death.

Aug 16, 2022

Hack Starlink and get up to $25,000 as a reward from SpaceX

Posted by in categories: cybercrime/malcode, Elon Musk, internet, space travel

Wikimedia Commons.

The Elon Musk space company may be popular for ferrying astronauts and cargo missions on its reusable rockets, but its satellite internet services have also made a mark in recent times. When Russia invaded Ukraine earlier this year, it also tried to break the communication chain inside the country by attacking its fiber optic network. However, SpaceX’s terminals were flown in, and connectivity was restored in a matter of days.

Aug 16, 2022

A new frontier in quantum science and technology

Posted by in categories: quantum physics, science

Purdue University researchers have unlocked a new area of quantum science and technology by utilizing photons and electron spin qubits to regulate nuclear spins in a two-dimensional material. They used electron spin qubits as atomic-scale sensors to effect the first experimental control of nuclear spin qubits in ultrathin hexagonal boron nitride.

The study could lead to applications such as atomic-scale nuclear magnetic resonance spectroscopy. It could also allow reading and writing quantum information with nuclear spins in 2D materials.

Aug 16, 2022

Statistical tool finds ‘gaps’ in DNA data sets shouldn’t be ignored

Posted by in categories: biotech/medical, evolution

A simple statistical test shows that contrary to current practice, the “gaps” within DNA protein and sequence alignments commonly used in evolutionary biology can provide important information about nucleotide and amino acid substitutions over time. The finding could be particularly relevant to those studying distantly related species. The work appears in Proceedings of the National Academy of Sciences.

Biologists studying evolution do so by looking at how DNA and protein sequences change over time. These changes can be sequence length changes—when specific are deleted or added at certain positions—or substitutions, where one nucleotide type is exchanged for a different type at a given point.

“Think of the DNA sequence and its evolution as a sentence being copied by different people over time,” says Jeff Thorne, professor of biological sciences and statistics at NC State and a co-corresponding author of the research. “Over time, a letter in a word will change—that’s a substitution. Leaving out or adding letters or words correspond to deletions or insertions.”

Aug 16, 2022

11 ways new technology changed the way we think about ancient Egyptian mummies

Posted by in category: futurism

From snake embalming rituals to mummy pregnancy to an ancient Egyptian priest’s voice, these discoveries were made without damaging the remains.

Aug 16, 2022

Are space scientists ready for Starship—the biggest rocket ever?

Posted by in category: space travel

SpaceX’s behemoth could upend research with its immense capacity and low costs.

Aug 16, 2022

New Elon Musk essay: Tesla CEO’s thoughts on technology and humanity

Posted by in categories: Elon Musk, robotics/AI, sustainability

It’s been a while since Elon Musk published an extensive blog post outlining his stance on a specific topic. On the official Tesla website, his last blog post was on August 24, 2018, when he explained his decision to keep Tesla a publicly-traded company. Fortunately, a new Elon Musk essay has been posted in China, outlining the Tesla CEO’s thoughts on a number of topics — from sustainability, the Tesla Bot’s real-world use, Neuralink’s focus on the disabled, and SpaceX’s exploration aspirations.

The new Elon Musk essay was published in China Cyberspace 0, the Cyberspace Administration of China’s (CAC) flagship magazine. A translation of the essay was posted by Yang Liu, a journalist from the state-owned news agency Xinhua 0, on the Beijing Channel blog. As could be seen in Liu’s post, Musk actually discussed a number of topics in detail.

In a way, the publication of the new Elon Musk essay in the CAC’s flagship magazine is significant. As noted by The Register 0, Musk’s essay suggests that Chinese authorities approve of the Tesla CEO’s positions on the topics he discussed. Only a few other foreign entrepreneurs would likely be given the same honor.

Aug 16, 2022

The entanglement of two quantum memory systems 12.5 km apart from each other

Posted by in categories: computing, internet, quantum physics

Quantum computing technology could have notable advantages over classical computing technology, including a faster speed and the ability to tackle more complex problems. In recent years, some researchers have also been exploring the possible establishment of a “quantum internet,” a network that would allow quantum devices to exchange information, just like classical computing devices exchange information today.