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The Ingenuity autonomous helicopter surpassed all expectations to fly dozens of missions over several years on the Red Planet, only stopping this year when an accident damaged one of its rotors

Hundreds of community websites run for fans of everything from cycling to Sunderland AFC may be forced to shut down by the UK's Online Safety Act, which is designed to protect children from harmful content

A newly described species of giant pitcher plant is one of the biggest ever found, with leaves covered in fur the same colour as orangutans

Blazing the Trail, a new podcast from the Australian Museum, delves into topics from how language evolved to the implications of harnessing fire

If RFK Jr. "researches" vaccines, he will certainly "discover" they cause autism. It's possible that this "research" will be used as justification to revoke authorization for vaccines. That's always been the endgame.

The post Trusting RFK Jr. to Research Vaccines is Like Trusting a Hungry Python to Babysit a Kitten first appeared on Science-Based Medicine.

We asked New Scientist writers to pick their favourite sci-fi short story. From H.G. Wells’s The Time Machine to Octavia E. Butler’s Bloodchild, via stories from George R. R. Martin and Ursula K. Le Guin, here are the results

A team of astronomers have detected a surprisingly fast and bright burst of energy from a galaxy 500 million light years away. The burst of radiation peaked in brightness just after 4 day and then faded quickly. The team identified the burst, which was using the Catalina Real-Time Transient Survey with supporting observations from the Gran Telescopio Canarias, as the result of a small black hole consuming a star. The discovery provides an exciting insight into stellar evolution and a rare cosmic phenomenon. 

Black holes are stellar corpses where the gravity is so intense that nothing, not even light can escape. They form when massive stars collapse under their own gravity at the end of their life forming an infinitely small point known as a singularity. The region of space around the singularity is bounded by the event horizon, the point beyond which, nothing can escape. Despite the challenges of observing them, they can be detected by observing the effects of their gravity on nearby objects like gas clouds. There are still many mysteries surrounding black holes so they remain an intense area of study. 

3D rendering of a rapidly spinning black hole’s accretion disk and a resulting black hole-powered jet. Credit: Ore Gottlieb et al. (2024)

A team of astronomers led by Claudia Gutiérrez from the Institute of Space Sciences and the Institute of Space Studies of Catalina used data from the Catalina Real-Time Transient Survey (CRTS) to explore transient events. The CRTS was launched in 2004 and is a wide field survey that looks for variable objects like supernova and asteroids. It uses a network of telescopes based in Arizona to scan large areas of sky to detect short-lived events. It has been of great use providing insights into the life cycle of stars and the behaviour of distant galaxies. 

The 60 inch Mt. Lemmon telescope is one of three telescopes used in the Catalina Sky Survey. Image: Catalina Sky Survey, University of Arizona.

The team detected the bright outburst in a galaxy located 500 million light years away and published their results in the Astrophysical Journal. The event took place in a tiny galaxy about 400 times less massive than the Milky Way. The burst was identified as CSS161010, it reached maximum brightness in only 4 days and 2.5 days later had it’s brightness reduced by half. Subsequent work revealed that previous detection had been picked up by the All-Sky Automated Survey for SuperNovae. Thankfully the detection was early enough to allow follow up observations by other ground based telescopes. Typically these types of events are difficult to study due to their rapid evolution.

Only a handful of events like CSS161010 have been detected in recent years but until now  their nature was a mystery. The team led by Gutiérrez have analysed the spectral properties and found hydrogen lines revealing material travelling at speeds up to 10% of the speed of light. The changes observed in the hydrogen emission lines is similar to that seen in active galactic nuclei where supermassive black holes exist. The observation suggests it relates to a black hole, although not a massive one.

The brightness of the object reduced 900 times over the following two months. Further spectral analysis at this time still revealed blue shifted hydrogen lines indicating high speed gas outflows. This was not something usually seen from supernova events suggesting a different origin. The team believe that the event is the result of a small black hole swallowing a star. 

Source : Astronomers detected a burst caused by a black hole swallowing a star

The post Star Devouring Black Hole Spotted by Astronomers appeared first on Universe Today.

A brotherly research duo has discovered that when the Large Hadron Collider (LHC) produces top quarks -- the heaviest known fundamental particles -- it regularly creates a property known as magic.

Meet the brown dwarf: bigger than a planet, and smaller than a star. A category of its own, it’s one of the strangest objects in the universe.

Brown dwarfs typically are defined to have masses anywhere from 12 times the mass of Jupiter right up to the lower limit for a star. And despite their names, they are not actually brown. The largest and youngest ones are quite hot, giving off a steady glow of radiation. In fact, the largest brown dwarfs are almost indistinguishable from red dwarfs, the smallest of the stars. But the smallest, oldest, and coldest ones are so dim they can only be detected with our most sensitive infrared telescopes.

Unlike stars, brown dwarfs don’t generate their own energy through nuclear fusion, at least not for very long. Instead they emit radiation from the leftover heat of their own formation. As that heat escapes, the brown dwarf continues to dim, sliding from fiery red to mottled magenta to invisible infrared. The greater the mass at its birth, the more heat it can trap and the longer it can mimic a proper star, but the ultimate end fate is the same for every single brown dwarf, regardless of its pedigree.

At first it may seem like brown dwarfs are just extra-large planets, but they get to do something that planets don’t. While brown dwarfs can’t fuse hydrogen in their cores – that takes something like 80 Jupiter masses to accomplish – they can briefly partake in another kind of fusion reaction.

In the cooler heart of a brown dwarf, deuterium, which is a single proton and neutron, can convert into Helium-3, and in the process release energy. This process doesn’t last long; in only a few million years even the largest brown dwarfs use up all their available deuterium, and from there they will just cool off.

As for their size, they tend not to be much larger in diameter than a typical gas giant like Jupiter. That’s because unlike a star, there isn’t an additional source of energy, and thereby pressure, to prop themselves up. Instead, all that’s left is the exotic quantum force known as degeneracy pressure, which means that you can only squeeze so many particles into so small a volume. In this case, brown dwarfs are very close to the limit for degeneracy pressure to maintain their size given their mass.

This means that despite outweighing Jupiter, they won’t appear much larger. And unlike Jupiter, they are briefly capable of nuclear fusion. After that, however, they spend the rest of their lives wandering the galaxy, slowly chilling out.

The post What Makes Brown Dwarfs So Weird? appeared first on Universe Today.

Researchers have found evidence of magnetic fields associated with a disc of gas and dust a few hundred light-years across deep inside a system of two merging galaxies known as Arp220. They say these regions could be the key to making the centres of interacting galaxies just right for cooking lots of hydrogen gas into young stars.

Scientist have begun to reveal the particle-level processes that create the type of auroras that dance rapidly across the sky. The Kinetic-scale Energy and momentum Transport experiment -- KiNET-X -- lifted off from NASA's Wallops Flight Facility in Virginia on May 16, 2021, in the final minutes of the final night of the nine-day launch window.

Scientist have begun to reveal the particle-level processes that create the type of auroras that dance rapidly across the sky. The Kinetic-scale Energy and momentum Transport experiment -- KiNET-X -- lifted off from NASA's Wallops Flight Facility in Virginia on May 16, 2021, in the final minutes of the final night of the nine-day launch window.

A team of chemists has unveiled a novel method to simplify the synthesis of piperidines, a key structural component in many pharmaceuticals. The study combines biocatalytic carbon-hydrogen oxidation and radical cross-coupling, offering a streamlined and cost-effective approach to create complex, three-dimensional molecules. This innovation could help accelerate drug discovery and enhance the efficiency of medicinal chemistry.

Artificial intelligence that is as intelligent as humans may become possible thanks to psychological learning models, combined with certain types of AI.

Recent findings show that Stonehenge’s stones came from all over Britain – and this offers clues to the monument’s purpose, say archaeologists

In a previous post, I showed you that the Standard Model, armed with its special angle θw of approximately 30 degrees, does a pretty good job of predicting a whole host of processes in the Standard Model. I focused attention on the decays of the Z boson, but there were many more processes mentioned in the bonus section of that post.

But the predictions aren’t perfect. They’re not enough to convince a scientist that the Standard Model might be the whole story. So today let’s bring these predictions into better focus.

There are two major issues that we have to correct in order to make more precise predictions using the Standard Model:

• In contrast to what I assumed in the last post, θw isn’t exactly 30 degrees
• Although I ignored them so far, the strong nuclear force makes small but important effects

But before we deal with these, we have to fix something with the experimental measurements themselves.

Knowledge and Uncertainty: At the Center of Science

No one complained — but everyone should have — that when I presented the experimental results in my previous post, I expressed them without the corresponding uncertainties. I did that to keep things simple. But it wasn’t professional. As every well-trained scientist knows, when you are comparing an experimental result to a theoretical prediction, the uncertainties, both experimental and theoretical, are absolutely essential in deciding whether your prediction works or not. So we have to discuss this glaring omission.

Here’s how to read typical experimental uncertainties (see Figure 1). Suppose a particle physicist says that a quantity is measured to be x ± y — for instance, that the top quark mass is measured to be 172.57± 0.29 GeV/c2. Usually (unless explicitly noted) that means that the true value has a 68% chance of lying between x-y and x+y — “within one standard deviation” — and a 95% chance of lying between x-2y and x+2y — “within two standard deviations.” (See Figure 1, where x and y are called and . The chance of the true value being more than two standard deviations away from x is about 5% — about 1/20. That’s not rare! It will happen several times if you make a hundred different measurements. But the chance of being more than three standard deviations away from x is a small fraction of a percent — as long as the cause is purely a statistical fluke — and that is indeed rare. (That said, one has to remember that big differences between prediction and measurement can also be due to an unforseen measurement problem or feature. That won’t be an issue today.)

Figure 1: Experimental uncertainties corresponding to , where is the “central value” and “” is a “standard deviation. W Boson Decays, More Precisely

Let’s first look at W decays, where we don’t have the complication of θw , and see what happens when we account for the effect of the strong nuclear force and the impact of experimental uncertainies.

The strong nuclear force slightly increases the rate for the W boson to decay to any quark/anti-quark pair, by about 3%. This is due to the same effect discussed in the “Understanding the Remaining Discrepancy” and “Strength of a Force” sections of this post… though the effect here is a little smaller (as it decreases at shorter distances and higher energies.) This slightly increases the percentages for quarks and, to compensate, slightly reduces the percentages for the electron, muon and tau (the “leptons”).

In Figure 2 are shown predictions of the Standard Model for the probabilities of the W- boson’s various decays:

• At left are the predictions made in the previous post.
• At center are better predictions that account for the strong nuclear force.

(To do this properly, uncertainties on these predictions should also be provided. But I don’t think that doing so would add anything to this post, other than complications.) These predictions are then compared with the experimental measurements of several quantities, shown at right: certain combinations of these decays that are a little easier to measure are also shown. (The measurements and uncertainties are published by the Particle Data Group here.)

Figure 2: The decay probabilities for W– bosons, showing the percentage of W bosons that decay to certain particles. Predictions are given both before (left) and after (center) accounting for effects of the strong nuclear force. Experimental results are given at right, showing all measurements that can be directly performed.

The predictions and measurements do not perfectly agree. But that’s fine; because of the uncertainties in the measurements, they shouldn’t perfectly agree! All of the differences are less than two standard deviations, except for the probability for decay of a W– to a tau and its anti-neutrino. That deviation is less than three standard deviations — and as I noted, if you have enough measurements, you’ll occasionally get one larger than two standard deviations. We still might wonder if something funny is up with the tau, but we don’t have enough evidence of that yet. Let’s see what the Z boson teaches us later.

In any case, to a physicist’s eye, there is no sign here of any notable disgreement between theory and experiment in these results. Within current uncertainties, the Standard Model correctly predicts the data.

Z Boson Decays, More Precisely

Now let’s do the same for the Z boson, but here we have three steps:

• first, the predictions when we take sin θw = 1/2, as we did in the previous post;
• second, the predictions when we take sin θw = 0.48;
• third, the better predictions when we also include the effect of the strong nuclear force.

And again Figure 3 compares predictions with the data.

Figure 3: The decay probabilities for Z bosons, showing the percentage of Z bosons that decay to certain particles. Predictions are given (left to right) for sin θw = 0.5, for sin θw =0.48, and again sin θw = 0.48 with the effect of strong nuclear force accounted for. Experimental results are given at right, showing all measurements that can be directly performed.

You notice that some of the experimental measurements have extremely small uncertainties! This is especially true of the decays to electrons, to muons, to taus, and (collectively) to the three types of neutrinos. Let’s look at them closely.

If you look at the predictions with sin θw = 1/2 for the electrons, muons and taus, they are in disagreement with the measurements by a lot. For example, in Z decay to muons, the initial prediction differs from the data by 19 standard deviations!! Not even close. For sin θw = 0.48 but without accounting for the strong nuclear force, the disagreement drops to 11 standard deviations; still terrible. But once we account also for the strong nuclear force, the predictions agree with data to within 1 to 2 standard deviations for all three types of particles.

As for the decays to neutrinos, the three predictions differ by 16 standard deviations, 9 standard deviations, and… below 2 standard deviations.

My reaction, when this data came in in the 1990s, was “Wow.” I hope yours is similar. Such close matching of the Standard Model’s predictions with highly precise measurements is a truly stunning sucesss.

Notice that the successful prediction requires three of the Standard Model’s forces: the mixture of the electromagnetic and weak nuclear forces given by the magic angle, with a small effect from the strong nuclear force. Said another way, all of the Standard Model’s particles except the Higgs boson and top quark play a role in Figs. 2 and 3. (The Higgs field, meanwhile, is secretly in the background, giving the W and Z bosons their masses and affecting the Z boson’s interactions with the other particles; and the top quark is hiding in the background too, since it can’t be removed without changing how the Z boson interacts with bottom quarks.) You can’t take any part of the Standard Model out without messing up these predictions completely.

Oh, and by the way, remember how the probability for W decay to a tau and a neutrino in Fig. 2 was off the prediction by more than two standard deviations? Well there’s nothing weird about the tau or the neutrinos in Fig. 3 — predictions and measurements agree just fine — and indeed, no numbers in Z decay differ from predictions by more than two standard deviations. As I said earlier, the expectation is that about one in every twenty measurements should differ from its true value by more than two standard deviations. Since we have over a dozen measurements in Figs. 2 and 3, it’s to be expected that one might well be two standard deviations off.

Asymmetries, Precisely

Let’s do one more case: one of the asymmetries that I mentioned in the bonus section of the previous article. Consider a forward-backward asymmetry shown in Fig. 4. Take all collisions in which an electron strikes a positron (the anti-particle of an electron) and turns into a muon and an anti-muon. Now compare the probability that the muon goes “forward” (roughly the direction that the electron is heading) to the probability that it goes “backward” (roughly the direction that the positron is heading.) If the two probabilities are equal, then the asymmetry would be zero; if the muon always goes to the left, then the asymmetry would be 100%; if always to the right, the asymmetry would be -100%.

Figure 4: In electron-positron collisions that make a muon/anti-muon pair, the forward-backward asymmetry compares the rate for “forward” production (where the muon travels roughly in the same direction as the electron) to “backward” production.

Asymmetries are special because the effect of the strong nuclear force cancels out of them completely, and so they only depend on sin θw. And this particular “leptonic forward-backward” asymmetry is an example with a special feature: if sin θw were exactly 1/2, this asymmetry for lepton production would be predicted to be exactly zero.

But the measured value of this asymmetry, while quite small (less than 2%), is definitely not zero, and so this is another confirmation that sin θw is not exactly 1/2. So let’s instead compare the prediction for this asymmetry using sin θw = 0.48, the choice that worked so well for the Z boson’s decays in Fig. 3, with the data.

In Figure 5, the horizontal axis shows the lepton forward-backward asymmetry. The prediction of 1.8% that one obtains for sin θw = 0.48, widened slightly to cover 1.65% to 2.0%, which is what obtains for sin θw between 0.479 and 0.481, is shown in pink. The four open circles represent four measurements of the asymmetry by the four experiments that were located at the LEP collider; the dashes through the circles show the standard deviations on their measurements. The dark circle shows what one gets when one combines the four experiments’ data together, obtaining an even better statistical estimate: 1.71 ± 0.10%, the uncertainty being indicated both as the dash going through the solid circle and as the yellow band. Since the yellow band extends to just above 1.8%, we see that the data differs from the sin θw = 0.480 prediction (the center of the pink band) by less than one standard deviation… giving precise agreement of the Standard Model with this very small but well-measured asymmetry.

Figure 5: The data from four experiments at the LEP collider (open circles, with uncertainties shown as dashes), and the combination of their results (closed circle) giving an asymmetry of 1.70% with an uncertainty of ±0.10% (yellow bar.) The prediction of the Standard Model for sin θw between 0.479 and 0.481 is shown in pink; its central value of 1.8% is within one standard deviation of the data.

Predictions of other asymmetries show similar success, as do numerous other measurements.

The Big Picture

Successful predictions like these, especially ones in which both theory and experiment are highly precise, explain why particle physicists have such confidence in the Standard Model, despite its clear limitations.

What limitations of the Standard Model am I referring too? They are many, but one of them is simply that the Standard Model does not predict θw . No one can say why θw takes the value that it has, or whether the fact that it is close to 30 degrees is a clue to its origin or a mere coincidence. Instead, of the many measurements, we use a single one (such as one of the asymmetries) to extract its value, and then can predict many other quantities.

One thing I’ve neglected to do is to convey the complexity of the calculations that are needed to compare the Standard Model predictions to data. To carry out these computations much more carefully than I did in Figs. 2, 3 and 5, in order to make them as precise as the measurements, demands specialized knowledge and experience. (As an example of how tricky these computations can be: even defining what one means by sin θw can be ambiguous in precise enough calculations, and so one needs considerable expertise [which I do not have] to define it correctly and use that definition consistently.) So there are actually still more layers of precision that I could go into…!

But I think perhaps I’ve done enough to convince you that the Standard Model is a fortress. Sure, it’s not a finished construction. Yet neither will it be easily overthrown.

In-plane magnetic fields are responsible for inducing anomalous Hall effect in certain films, report researchers. By studying how these fields change electronic structures, the team discovered a large in-plane anomalous Hall effect. These findings pave the way for new strategies for controlling electronic transport under magnetic fields, potentially advancing applications in magnetic sensors.

In-plane magnetic fields are responsible for inducing anomalous Hall effect in certain films, report researchers. By studying how these fields change electronic structures, the team discovered a large in-plane anomalous Hall effect. These findings pave the way for new strategies for controlling electronic transport under magnetic fields, potentially advancing applications in magnetic sensors.

Combining the adsorption properties of solids with the dissolution capabilities of liquids, researchers have created a versatile and efficient material for improving oxygen separation in gases. In addition to increasing the supply of affordable oxygen, they are developing their material to separate a variety of gases, increasing its use in industry and potentially controlling greenhouse gases.

The future of data security depends on the reliable application of quantum technology, but its widespread adoption requires rigorous verification. Researchers have developed a novel approach to verify quantum protocols, ensuring their reliability in safety- and security-critical applications. This advancement addresses the need for trustworthy quantum systems, which is essential for the secure deployment of quantum technologies in high-reliability systems.