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New research has shown how the quantum mechanical principle of strong coupling opens unrivalled possibilities for designing optical filters.

Artificial intelligence provides new evidence that rapid decarbonization will not prevent warming beyond 1.5 degrees Celsius. The hottest years of this century are likely to shatter recent records.

Researchers have created organic materials for brain and heart pacemakers, which rely on uninterrupted signal delivery to be effective. Using a plastic base known as polypropylene, the researchers added a specially formulated clay called Montmorillonite and different ratios of graphene, one of the strongest lightweight materials. They created five different materials that could be performance-tested and took detailed measurements of the structure of the composite materials using scanning electron microscopy.

Scientists have developed a unique nanolaser. Although the dimensions of this laser are so small that its structure can only be seen through a powerful microscope, its potential is vast. With applications in early medical diagnostics, data communication, and security technologies, this invention could also become a key tool for the study of light and matter interactions.

Atoms cooled to near absolute zero let researchers make a measurement of gravity 20 per cent more precise than the standard quantum limit usually allows

Dyson spheres and rings have always held a special fascination for me. The concept is simple, build a great big structure either as a sphere or ring to harness the energy from a star. Dyson rings are far more simple and feasible to construct and in a recent paper, a team of scientists explore how we might detect them by analysing the light from distant stars. The team suggests they might be able to detect Dyson rings around pulsars using their new technique.

Like their spherical cousins, Dyson rings remain for now, a popular idea in science fiction yet they are starting to appear more and more in scientific debates. The concept of the ring is similar to the sphere, a megastructure designed to encircle a star, harnessing its energy on a gargantuan scale. It might consist of a series of satellites or even habitats in a circular orbit with solar collectors and unlike the spheres, require far less resources to build. The concept of the sphere was first proposed by physicist and mathematician Freeman Dyson in 1960. Such structures might be detectable and reveal the existence of intelligent civilisations. 

A Type II civilization is one that can directly harvest the energy of its star using a Dyson Sphere or something similar. Credit: Fraser Cain (with Midjourney)

It’s fascinating to think about civilisations building such constructions. Our own civilisation currently consumes around 15,000 terawatts per hour and that number is only going to increase as our population grows and we become even more reliant on technology. To endeavour to quantify the energy usage from the level of technological capability, the Kardashev scale was developed. On this scale, we are currently at Type I which means our power usage is  4 × 1019 erg s?1 (4 terawatts) If a civilisation requires 4 × 1033 erg s?1 (400 trillion terawatts) then it is considered to be type II and it is these civilisations that may be capable and indeed it may be necessary to build Dyson structures. 

To create either a solid sphere or even a sphere with orbiting satellites would require phenomenal amounts of material. A sphere which had a radius of 1 astronomical unit (the average distance between Earth and the Sun) would require more material than exists in the entire Solar System. It is far more likely that civilisations would create ring structures. Rings of this nature around a star would be able to harness significant amounts of energy but a ring around a pulsar would, if the pulse beam of the star could be tracked, be able to capture even more energy, of the order of 10 thousand trillion terawatts.

There are Dyson rings and spheres and this, an illustration of a Dyson swarm. Could this or a variation of it be what we’re detecting around KIC? Not likely, but a fun thought experiment. Credit: Wikipedia

In the paper written by Ogetay Kayali from Michigan Technological University and team, they propose further exploration of pulsar light curves to see if features that could reveal their presence have been missed. The features the team suggest arise from effects of the pulsar beam striking the ring structure. The beams travel at superluminal speeds which could result in multiple images of the pulsar spot on the Dyson ring appearing simultaneously. This may be visible in light curve analysis. A similar effect is seen when dust rings are illuminated with pulsar radiation.

Source : Search for Dyson Rings Around Pulsars: Unexpected Light Curves 

The post New Technique for Spotting Dyson Rings Unveiled. appeared first on Universe Today.

The ocean carbon sink – which removes about a quarter of our emissions from the atmosphere each year – was much weaker than expected in 2023

Dog owners often wonder what's really going on between their pets' fluffy ears. Now, savvy experiments and new technology are finally giving us a clearer glimpse

Sometimes in astronomy, a simple question has a difficult answer. One such question is this: what is the mass of our galaxy?

On Earth, we usually determine the mass of an object by placing it on a scale or balance. The weight of an object in Earth’s gravitational field lets us determine the mass. But we can’t put the Milky Way on a scale. Another difficulty with massing our galaxy is that there are two types of mass. There is the mass of dark matter that makes up most of the Milky Way’s mass, and there is all the regular matter like stars, planets, and us, which is known as baryonic matter.

We have several approaches to determining the total galactic mass, which usually involves measuring the speed of things such as stars, globular clusters, or nearby galaxies. Each of these approaches have strengths and weaknesses, though they all give a total value of a trillion solar masses, give or take a few hundred billion. All of these methods, however, only tell us the total mass. They say nothing about how much of the galaxy is baryonic mass. While baryonic mass is only a fraction of the total, it is what gives us all sorts of cool things like star formation, planetary systems, and digital watches.

Calculating the baryonic mass of our galaxy is even more difficult because you have to count up all the mass of regular stuff without counting dark matter. That’s relatively easy to do for things like stars and dense molecular clouds, but it’s much more challenging for things such as diffuse interstellar clouds. This is particularly true for the halo of stars and gas surrounding the Milky Way. No matter how much stuff we see at the fringes of our galaxy, there may be even more lurking about we haven’t seen. Which is why a new study looks at high-velocity clouds (HVCs) in the halo.

Most of the baryonic matter we have accounted for moves around the galaxy at the same rate. It’s easier to track things if you have an idea about how they move. But high-velocity clouds are different. They are interstellar clouds of hydrogen that can speed through the galactic halo at up to 500 km/s, and they often travel in directions very different from the galactic plane. Some astronomers have argued that HVCs might comprise a good portion of baryonic matter in the halo. So the team looked at data from the Galactic All Sky Survey (GASS) to determine whether this is true.

An image of the total GASS dataset. Credit: S. Janowiecki

The GASS survey was made by the Parkes radio telescope in Australia and captured radio emissions from neutral hydrogen gas seen in the Southern Hemisphere. Since HVCs are mostly made of neutral hydrogen, they are contained in the GASS data. But GASS only tells us the direction and relative motion of these clouds, so the team had to estimate their distance. They did this by comparing the motion of the HVCs relative to the motion of the Magellanic clouds. Also, since GASS only observed portions of the southern sky, the authors used Bayesian statistics to calculate the distribution of HVCs within the entire galaxy.

Previous observations of high-velocity clouds within the galactic disk of the Milky Way show that HVCs comprise a fraction of a percent of baryonic matter there. A simple extrapolation to the halo would suggest that up to 10% of halo baryonic mass could be due to HVCs. But this new work estimates the true value is closer to 0.1%, meaning that they comprise an insignificant fraction of baryonic mass in our galaxy’s halo. But the authors stress that their calculations are based on their assumptions of cloud distances, which could be wrong. Further radio surveys would be needed to pin down the HVC distances to obtain a better value.

Reference: Tahir, Noraiz, Martín López-Corredoira, and Francesco De Paolis. “The baryonic mass estimates of the Milky Way halo in the form of high-velocity clouds.” New Astronomy 115 (2025): 102328.

The post High Velocity Clouds Comprise Less of the Milky Way’s Mass Than We Thought appeared first on Universe Today.

Leading archaeologists share the biggest recent advances in our understanding of human evolution, and their hopes for the exciting finds the next five years may have in store

Happy Tuesday; it’s December 10, 2024, and Coynezaa is just around the corner. There’s another holiday, too, but it celebrates a myth, whereas I am real.

It has been a hectic three days, but also fun: giving two talks (I fell off the stage during the first one), touring around Katowice, and eating large quantities of hearty Silesian food. I have a gazillion photos, but, as I’m cooling my heels in the airport in Frankfurt, I have no time to post them—save one. And that is the picture below, showing yours truly eating a classic German comestible in the airport.

If I look a wreck, I am. My plane left Katowice for Frankfurt at 6 a.m., which meant boarding at 5:30, which meant getting up at 2:00 a.m. and leaving my hotel, some distance from the planes, at 3 a.m.

I went to bed at 9, hoping for five hours of sleep, but woke up at 12:15, soon after midnight, and what with the excitement of impending travel it was clear that I wasn’t going back to sleep. So I watched CNN instead (the only English t.v. channel) to discover, via Anderson Cooper, that the police had actually caught the man accused of shooting health executive Brian Thompson. When the law caught up to him, the suspect, one Luigi Mangioni of New Jersey, was chowing down at a McDonald’s in Altoona, Pennsylvania.  And it doesn’t look good for him:

The Altoona officers who took Mr. Mangione into custody found that he had several telltale items that might tie him to Mr. Thompson’s killing, a crime that has riveted the nation while exposing Americans’ deep-seated anger toward the U.S. health insurance industry.

Mr. Mangione, officials said, had a gun and a silencer similar to the ones used in the Dec. 4 shooting, and a fake driver’s license that matched one used by the man suspected in the killing.

He also carried with him a three-page handwritten manifesto condemning the health care industry for putting profits over patients.

“These parasites had it coming,” it said, according to a senior law enforcement official who saw the document. It added: “I do apologize for any strife and trauma, but it had to be done.”

The document specifically mentioned UnitedHealthcare, the insurance giant where Mr. Thompson was chief executive, noting its size and the amount of revenue it takes in, the official said.

Yes, he’s presumed innocent until found guilty, but I’m here to tell you that the probability of any other verdict seems nil. He’s 26 and will surely, if convicted, spend the rest of his natural life behind bars.

Read more about the pinch at the archived link here. It was a nifty bit of police work, made easier by Mangione pulling his mask down just one time, when he was flirting with a woman at a hostel.  But once was enough: look at the hostel picture and compare it to the many circulating pictures of Mangione. I’m glad he’s caught, for nobody deserves vigilante execution, which is capital punishment without a trial. In fact, I don’t believe anybody deserves execution at all. Life without parole is more than enough, and remember that some people can reform.

But they’re very sad about the arrest over at P********a, where the fulminating miscreants are not only delighted, but have been egged on in their hatred by the Chief Miscreant himself, who urges his baying hounds before pulling the trigger to first find out who heads healthcare corporations that deny claims.  Then, as the capo says, “After you’ve followed the chain of decisions, then you can consider terminating some rich a-hole. It’s the polite thing to do.”

Indeed, nothing makes you look better to “progressives” than urging your readers to murder rich people, preferably CEOs of healthcare corporations.

In other news, where is Bashar al-Assad? Is he dead, as some suspect? Or has he fled to his pals in Russia?

Paul Krugman has written his last column for the NYT, and, over in France, the right-wing Marine Le Pen is plotting to topple the French government and replace it with one far more to the right. Sound familiar?

There are reports of continuing peace talks between Israel and Hamas, but I don’t think they’ll amount to much. If they result in releasing thousands of convicted Palestinian terrorists from jail, while not letting all the hostages go—indeed, if a settlement leaves anything of Hamas to govern Gaza, Israel will have lost.

And that’s the nooz till I get home and take a day to recover.

Meanwhile, in Dobrzyn, Hili raises an old question: can animals think of the future?

Hili: I do not see the future.
A: It’s around the corner.

Hili: Nie widzę przyszłości.
Ja: Jest za rogiem.

Skeptoid answers another round of questions from students all around the world.

Researchers found that adolescents with more symptoms of gaming addiction showed lower brain activity in the region involved in decision-making and reward processing; this blunted response to reward anticipation is associated with higher symptoms of gaming addiction over time and suggests that reduced sensitivity to rewards, in particular non-gaming rewards, may play a role in problematic gaming.

Helical structures are ubiquitous across biology, from the double-stranded helix of DNA to how heart muscle cells spiral in a band. Inspired by this twisty ladder, researchers have developed an artificial polymer that organizes itself into a controlled helix. Helical structures are ubiquitous across biology, from the double-stranded helix of DNA to how heart muscle cells spiral in a band. Inspired by this twisty ladder, researchers have developed an artificial polymer that organizes itself into a controlled helix.

The anthropic principle states that the fundamental parameters of the Universe such as the strength of the fundamental forces, have been finely tuned to support life. Whether this is true or not or whether it is even worthy of scientific investigation has been hotly debated. A new paper proposes some ways that this may now be tested and perhaps brings the topic under scientific scrutiny for the first time.

The idea of the anthropic principle was first suggested by physicist Brandon Carter in 1973. The proposal by Carter was tabled at a conference to mark the 500th anniversary of the birth of Nicolaus Copernicus. The principle attempts to rationalise the apparent ‘fine tuning’ of various universal parameters that support a cosmos where observers like humans can exist. If the parameters are slightly different, life may not have evolved.

Nicolaus Copernicus portrait from Town Hall in Torun (Thorn), 1580. Credit: frombork.art.pl

There are two versions; the Weak Anthropic Principle which postulates we observe the universe as being compatible with our very existence because, the argument goes, we wouldn’t be here to observe it if not! Then there is the Strong Anthropic Principle which goes much further stating simply that the universe must have parameters that make life possible. 

Science of philosophy? Either way, for a theory to be of any use, it must be possible to test it. Until now it’s been thought the anthropic principle was beyond the possibility of being tested. The paper, published in the Journal of Cosmology and Astroparticle Physics was authored by Nemanja Kaloper from the University of California and Alexander Westphal from the Deutsches Elektronen-Synchrotron. They propose for the first time, a way that the principle can be experimentally tested.

The AP proposes that if the universe is to develop as a place that our carbon based life can evolve, it must have begun with a very specific set of parameters. The gravitational constant, Planck’s constant and the electron charge are such parameters that, if they had been different at the beginning of time, the universe would have been very different, very different indeed. 

Kaloper and Westphal identify the initial parameters implied by the anthropic principle and are able to model how the universe would have evolved. It would then be possible to compare the result to the cosmos observed today. Any variance between the model and the observed universe would provide a measure of the validity of the principle. 

A computer model of the large-scale structure of the universe using the Illustris simulator. This image depicts the dark matter and gas involved in forming galaxies and galaxy clusters, as well as the filaments connecting them. Image Credit: Illustris TNG

There are a number of predictions the team say can be used as a measure including the cosmic inflation and the nature of dark matter. Perhaps frustratingly close now to proving, in some way, the validity of the principle yet we are still a few more years away from being able to acquire all the necessary evidence. Until then, the anthropic principle remains a very interesting curiosity and one that, since the publication of this latest paper, does at least deserve our attention. 

Source : Falsifying anthropics

The post Has the Universe Been Designed to Support Life? Now We Have a Way to Test it! appeared first on Universe Today.

As a species, we’ve come to the awareness that we’re a minuscule part of a vast Universe defined by galaxy superclusters and the large-scale structure of the Universe. Driven by a healthy intellectual curiosity, we’re examining our surroundings and facing the question posed by Nature: how did everything get this way?

We only have incremental answers to that huge, almost infinitely-faceted question. And the incremental answers are unearthed by our better instruments, including space telescopes, which get better and more capable as time passes.

Enter the James Webb Space Telescope.

One of the reasons NASA and their partners built and launched the James Webb Space Telescope is to study the history of galaxy formation and to understand how they evolved into what we see today. That involves observing galaxies, galaxy clusters, galaxy superclusters, and the complex network of sheets, voids, and filaments that comprise the large-scale structure of the Universe. It also involves observing proto-clusters, the early stage of a galaxy cluster. They’re like building blocks for the cosmic web, which collapse and merge to form clusters and superclusters.

The Spiderweb protocluster is an ancient and well-studied object in the early Universe. More than 100 individual galaxies are forming a cluster at redshift z = 2.16, meaning it took more than 10 billion years for its light to reach us.

“We are observing the build-up of one the largest structures in the Universe, a city of galaxies in construction.”

Jose M. Pérez-Martínez, Instituto de Astrofísica de Canarias

Protoclusters are one key to understanding the Universe, and in two new papers, researchers present the results of the JWST’s observations of the Spiderweb protocluster. Among other things, the results show that gravity doesn’t play as large a role as thought in the formation of a cluster.

The difficulty in observing the Spiderweb is that it’s obscured by a healthy amount of cosmic dust. The dust blocks visible light but allows infrared light through. Since the JWST is an enormously powerful infrared telescope, its gaze has revealed things previously hidden from astronomers.

“We are observing the build-up of one the largest structures in the Universe, a city of galaxies in construction,” explained Jose M. Pérez-Martínez of the Instituto de Astrofísica de Canarias and the Universidad de La Laguna in Spain. “We know that most galaxies in local galaxy clusters (the biggest metropolises of the Universe) are old and not very active, whereas in this work we are looking at these objects during their adolescence. As this city in construction grows, their physical properties will also be affected. Now, Webb is giving us new insights into the build-up of such structures for the first time.”

The JWST can observe hydrogen gas more thoroughly than other telescopes. Astronomers often observe hydrogen-alpha (h-alpha) emissions to probe galaxies. h-alpha emissions are a specific type of light emitted when electrons transition between energy levels. However, there’s another type of infrared hydrogen emission called Paschen-beta emissions (Pa-beta) that the JWST can observe. It’s emitted by different electron transitions in hydrogen and is a valuable tracer of the star formation rate (SFR) in galaxies. While the JWST isn’t specifically designed to single out these emissions, it can observe the infrared wavelengths that include the Pa-beta line.

The two new papers based on the JWST observations are:

• JWST/NIRCam Pa-beta Narrowband Imaging Reveals Ordinary Dust Extinction for H? Emitters within the Spiderweb Protocluster at z = 2.16
• JWST/NIRCam Narrowband Survey of Pa-beta Emitters in the Spiderweb Protocluster at z = 2.16

These observations revealed the presence of new, previously undetected galaxies in the protocluster that were obscured by dust.

Using the NASA/ESA/CSA James Webb Space Telescope, an international team of astronomers has found new galaxies in the Spiderweb protocluster. They found that gravitational interactions in these dense regions are not as important as previously thought. This annotated image shows the galaxy distribution in the Spiderweb protocluster as seen by Webb’s NIRCam (Near-InfraRed Camera). The galaxies are annotated by white circles, and the collection of gravitationally-bound galaxies is identified in the centre of the image. A selection of these galaxies are featured as individual close-ups at the bottom of the image. Image Credit: ESA/Webb, NASA & CSA, H. Dannerbauer

“As expected, we found new galaxy cluster members, but we were surprised to find more than expected,” explained Rhythm Shimakawa of Waseda University in Japan. “We found that previously-known galaxy members (similar to the typical star-forming galaxies like our Milky Way galaxy) are not as obscured or dust-filled as previously expected, which also came as a surprise.”

The characteristics of the dust show that gravitational interactions aren’t playing as large a role as thought. If there were gravity-driven mergers, the dust production would be higher as mergers trigger rapid SFRs. However, these observations show that the dust is being produced smoothly rather than abruptly.

“This can be explained by the fact that the growth of these typical galaxies is not triggered primarily by galaxy interactions or mergers that induce star-formation,” added Helmut Dannerbauer of the Instituto de Astrofísica de Canarias in Spain. “We now figure this can instead be explained by star formation that is fueled through gas accumulating at different locations all across the object’s large-scale structure.”

“These results support the scenario for which dust production within the main galaxy population of this protocluster is driven by secular star formation activities fueled by smooth gas accretion across its large-scale structure,” the authors write in the first paper. “This downplays the role of gravitational interactions in boosting star formation and dust production within the Spiderweb protocluster, in contrast with observations in higher redshift and less evolved protocluster cores.”

“We find no correlation between the dustiness of our sample of HAEs and their distribution in phase space (spectroscopic sample) or as a function of the projected clustercentric radius or local density,” the authors of the first paper explain. If gravity-driven mergers were behind the star and dust formation, it would be clumpy.

The second paper’s original goal was to make a deep-line survey aimed at Pa-beta emitters (PBEs). It used a unique narrow-band filter on the NIRCam that’s less sensitive to dust extinction. They ended up detecting new member candidates in the Spiderweb Protocluster. Interestingly, not all of the h? emitters are also Pa-beta emitters.

The researchers narrowed their Pa-beta emitters down to 41 sources. Only 17 of those are also confirmed as h? emitters. “The remaining 24 objects are considered to be unconfirmed candidates associated with the Spiderweb protocluster,” the authors write. “These PBE candidates are still at risk of foreground or background emitters other than PBEs; therefore, further follow-up studies are needed to establish that they are protocluster members.”

Finding more members of the Spiderweb protocluster and finding that gravity isn’t as important as thought is just a beginning. These are incremental answers on our path to understanding how the Universe evolved into what we see today. Science is a journey, and as is so often the case on the journey, more observations are the next step.

“Follow-up confirmations and characterizations of the PBE candidates will provide a better understanding of the total star formation rate in the Spiderweb protocluster, the environmental dependence of galaxy formation, and a transition process from a protocluster to a bona fide cluster of galaxies,” the authors of the second paper write in their conclusion.

The researchers intend to follow up this work with more spectroscopic observations form the JWST. Those observations should provide additional confirmation of the Spiderweb’s new members.

The post Webb Sees a Supercluster of Galaxies Coming Together appeared first on Universe Today.

A NASA Hubble Space Telescope observation program called OPAL (Outer Planet Atmospheres Legacy) obtains long-term baseline observations of Jupiter, Saturn, Uranus, and Neptune in order to understand their atmospheric dynamics and evolution.

Imagine an artificial intelligence (AI) model that can watch and understand moving images with the subtlety of a human brain. Now, scientists have made this a reality by creating MovieNet: an innovative AI that processes videos much like how our brains interpret real-life scenes as they unfold over time.

Imagine an artificial intelligence (AI) model that can watch and understand moving images with the subtlety of a human brain. Now, scientists have made this a reality by creating MovieNet: an innovative AI that processes videos much like how our brains interpret real-life scenes as they unfold over time.