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Mar 8, 2023

Nearby active galaxy investigated with Chandra observatory

Posted by in category: cosmology

Using NASA’s Chandra X-ray observatory, astronomers have performed deep X-ray observations of a nearby active galaxy known as NGC 5,728 and its active galactic nucleus (AGN). Results of the observational campaign, published March 1 on the pre-print server arXiv, deliver important information regarding the properties of this AGN and the emission from it.

AGN are compact regions at the center of a galaxy, more luminous than the surrounding galaxy light. They are very energetic due either to the presence of a black hole or activity at the core of the galaxy.

Located some 146 million light years away in the constellation of Libra, NGC 5,728 is an active barred spiral galaxy with a size of nearly 100,000 light years and an estimated mass of about 72 billion solar masses. It is a Seyfert galaxy of type 1.9, with a heavily obscured and complex AGN powered by a (SMBH) at its center.

Mar 8, 2023

Scientists reveal molecular structure of bacterial gas vesicles

Posted by in categories: nanotechnology, physics

Similar in function to ballast tanks in submarines or fish bladders, many water-based bacteria use gas vesicles to regulate their floatability. In a new publication in Cell, scientists from the Departments of Bionanoscience and Imaging Physics now describe the molecular structure of these vesicles for the first time. These gas vesicles were also recently repurposed as contrast agents for ultrasound imaging.

Gas vesicles (GVs) are hollow, cylindrical nanostructures made of a thin protein-based shell and filled with gas. Similar in function to ballast tanks in submarines or fish bladders, many water-based bacteria use these structures to regulate their floatability. “For example, certain cyanobacteria use gas vesicles to float to the surface in order to harvest light for photosynthesis, a phenomenon sometimes seen at enormous scale in toxic algal blooms,” says Arjen Jakobi, Assistant Professor at the Department of Bionanoscience.

There are very specific requirements for such structures: for bacteria to stay afloat, GVs must occupy a substantial proportion of the cell, which involves forming compartments that extend over hundreds of nanometers in size. To maximize floatability, the shell must be constructed from minimal material. At the same time, the shell needs to provide resistance to the pressure from the surrounding water to maintain the ability to float with changes in water depth. GVs have therefore evolved as rigid, thin-walled structures composed of a single protein that repeats many thousands of times to form the GV shell.

Mar 8, 2023

Black Holes Will Destroy All Quantum States, Researchers Argue

Posted by in categories: cosmology, quantum physics

New calculations suggest that the event horizons around black holes will ‘decohere’ quantum possibilities — even those that are far away.

Mar 8, 2023

Crash Course: Artificial Intelligence Vs. Humanity

Posted by in category: robotics/AI

AI chatbots challenge us to wonder whether we’ll stay in control of the bots or whether they’ll control us.

Mar 8, 2023

Astronomers detect water molecules swirling around a star

Posted by in categories: materials, space

A nearby star system is helping astronomers unravel the mystery of how water appeared in our solar system billions of years ago.

Scientists observed a young star, called V883 Orionis, located 1,300 light-years away using the Atacama Large Millimeter/submillimeter Array of telescopes, or ALMA, in northern Chile.

The star is surrounded by a planet-forming disk of cloud of gas and dust leftover from when the star was born. Eventually, material in the disk comes together to form comets, asteroids and planets over millions of years.

Mar 8, 2023

Floating Frogs

Posted by in categories: particle physics, space

Year 1997 Basically this detailed the use of magnetism to levitate frogs.


When pigs fly? That could be sooner than you think. A group of researchers in the Netherlands and in England has made a frog levitate in a magnetic field. Although the feat might seem no more than a curiosity, researchers say that the floating amphibians may lead the way to a cheap alternative to space-based science experiments.

Many materials are diamagnetic—that is, when placed near a magnet, their atoms fight the magnetic field, and the object tries to scoot away. If such a material is placed in a strong enough magnetic field, it levitates. Superconductors, for example, are perfect diamagnets and can levitate over even weak magnets, which is why levitating trains like those in Japan can fly over the tracks. Organic material like living cells is very weakly diamagnetic, says J. C. Maan, a physicist at the University of Nijmegen in the Netherlands. So he and colleagues employed a very strong magnet (chiefly used for crystallography experiments) to float the frog. It took 16 teslas—a very powerful field indeed—to lift the confused amphibian off the ground.

“It’s a little surprising how easy it is to do this,” says James Brooks, a physicist at the National High Magnetic Field Laboratory in Tallahassee, Florida. “It’s not incredibly exotic equipment. Any scientist who is awake will ask ‘What can I do with this?’” Brooks notes that the magnetic fields might provide a way to study materials in milligravity—without sending them into space—because the levitating object is in a net zero field. Researchers could study the effects of microgravity on crystal growth and also on the growth and development of living cells, without costly space missions.

Mar 8, 2023

Quantum computing is the key to consciousness

Posted by in categories: health, internet, quantum physics, robotics/AI

With the rapid development of chatbots and other AI systems, questions about whether they will ever gain true understanding, become conscious, or even develop a feeling agency have become more pressing. When it comes to making sense of these qualities in humans, our ability for counterfactual thinking is key. The existence of alternative worlds where things happen differently, however, is not just an exercise in imagination – it’s a key prediction of quantum mechanics. Perhaps our brains are able to ponder how things could have been because in essence they are quantum computers, accessing information from alternative worlds, argues Tim Palmer.

Ask a chatbot “How many prime numbers are there?” and it will surely tell you that there are an infinite number. Ask the chatbot “How do we know?” and it will reply that there are many ways to show this, the original going back to the mathematician Euclid of ancient Greece. Ask the chatbot to describe Euclid’s proof and it will answer correctly [ii]. [ii.

Of course, the chatbot has got all this information from the internet. Additional software in the computer can check that each of the steps in Euclid’s proof is valid and hence can confirm that the proof is a good one. But the computer doesn’t understand the proof. Understanding is a kind of Aha! moment, when you see why the proof works, and why it wouldn’t work if a minor element in it was different (for example the proof in the footnotes doesn’t work if any number but 1 is added when creating the number Q). Chatbots don’t have Aha! moments, but we do. Why?

Mar 8, 2023

Strange life forms create an “alien” ecosystem in an abandoned uranium mine

Posted by in category: futurism

Slimy biofilms made up of bacterial and eukaryotic life forms have taken over an abandoned, flooded uranium mine in Germany.

Mar 8, 2023

Analyze This: Algae behind blue-glowing waves light up a new device

Posted by in category: materials

Some algae glow blue when they experience forces. Held in transparent plastic, they now make devices light up in response to gentle pushes and tugs.

Mar 8, 2023

Antimatter neutrinos detected from a nuclear reactor 240 km away

Posted by in categories: nuclear energy, particle physics

A water-based detector has been used to spot antineutrinos from nuclear reactions hundreds of kilometres away. It could be used to monitor distant nuclear activities.

By Karmela Padavic-Callaghan