- Cosmic rays have been discovered coming out of Antarctica.
- No high-speed particle we know of could possibly go in one side of the earth and come out the other.
- All of the proposed explanations are exciting, especially the most likely one.
Meet ANITA. ANITA stands for "Antarctic Impulsive Transient Antenna." It seeks out cosmic rays from space as while hanging from a balloon suspended over Antarctica. In the last two years, though, it has twice detected cosmic rays coming from a direction no one expected: inside the earth. According to the Standard Model (SM) of physics, this shouldn't be possible.
ANITA, foreground, and its balloon, background(NASA)
And guess what? ANITA’s not alone
In September, a paper was submitted for peer review by astrophysicists at Penn State led by Derek Fox. "I was like, 'Well this model doesn't make much sense,'" Fox tells Live Science, "but the [ANITA] result is very intriguing, so I started checking up on it. I started talking to my office neighbor [and paper co-author] Steinn Sigurdsson about whether maybe we could gin up some more plausible explanations than the papers that have been published to date." Lacking any, they looked for other similar events and found three. They'd been detected by a surface-based Antarctic neutrino detector called, sensibly enough, IceCube. And when the data from ANITA and IceCube when combined, the Penn State scientists started getting excited. They calculate that whatever kind of particle is flying up and away from Earth has a less than 1-in-3.5 million chance of being any of the particles predicted by the Standard Model. Obviously, this has physicists scratching their heads trying to figure out what on earth is going on.
IceCube
How cosmic rays are supposed to behave
First of all, of course, cosmic rays are supposed to come from out there somewhere, not here. The earth is bombarded with them all the time. The suspicion is that the newly detected particles are cosmic rays slamming into the earth on one side and somehow making it out the other.
Cosmic rays, though, are high-energy particles with relatively wide cross-sections that lead to their demise by causing them to crash into matter inside the Earth. They're "mainly (89%) protons — nuclei of hydrogen, the lightest and most common element in the universe — but they also include nuclei of helium (10%) and heavier nuclei (1%), all the way up to uranium particles," according to CERN. Low-energy neutrinos, on the other hand, can pass through the earth's rocky mass, but they're not involved with cosmic rays.
Both ANITA and IceCube track neutrinos indirectly by detecting their remains, if you will. They detect the particles neutrinos produce when they decay post-collision. Since neutrinos can't get through the earth, though, something else is producing these particles. But what?
Artist rendition of cosmic rays
(koya979/Shutterstock)
They could be a new kind of particle…
One candidate put forward as responsible for the event is the elusive "sterile neutrino," first hinted at by evidence captured in the mid 1990s at the Liquid Scintillator Neutrino Detector (LSND) at Los Alamos. The data was interpreted as suggesting a weird kind of high-speed neutrino that simply passes through matter without any interaction. No one else was able to reproduce the result, and the idea fell out of favor. Until this last spring, that is, when MiniBooNE at Chicago's FermiLab captured new signs that it might exist. The sterile neutrino would break the Standard Model if confirmed, which is one of the things that make MiniBoonE's data exciting. "That would be huge," says Duke physicist Kate Scholberg, who wasn't involved with the research, "…that would require new particles ... and an all-new analytical framework."
Others have suggested that it could be a product of dark matter. Cool as either of these ideas would be, perhaps the strongest reason for the detected upward cosmic rays is even more thrilling.
…or they could be long-sought supersymetrical particles
According to the Standard Model, every particle has a symmetrical partner, but the particles we know about don't match up. To resolve this apparent imbalance, a class of thus-far-hidden "supersymmetrical" particles has been proposed. It was hoped that the Large Hadron Collider could detect these mysterious — and so far just theoretical — particles, but no. Since 2012, when the last known particle predicted the Standard Model, the Higgs-Boson, was detected, nothing new's been found.
Until, maybe, now.
What the Penn paper proposes
The Penn State paper suggests these South Pole upward cosmic rays could be our first sign of supersymmetricals, specifically the partner of the Standard Model's tau leptons. With a a couple of "S"es added to signify supersymmetry, they'd be stau sleptons.
Others agree that they could be the first actual evidence of supersymmetry. Los Alamos physicist Bill Louis tells LiveScience, "I think it's very compelling," though he adds that the pinpointing of a stau slepton is "a bit of a stretch."
Fox admits he certainly can't be sure, but that, "From my perspective, I go trawling around trying to discover new things about the universe, I come upon some really bizarre phenomenon, and then with my colleagues, we do a little literature search to see if anybody has ever thought that this might happen. And then if we find papers in the literature, including one from 14 years ago that predict something just like this phenomenon, then that gets really high weight from me." And, guess what, he did find a prediction from 2003 of stau sleptons showing up just like this.
Excavation of a triceratops skull in South Dakota.
David Schmidt, a geology professor at Westminster College, had just arrived in the South Dakota Badlands in summer 2019 with a group of students for a fossil dig when he received a call from the National Forest Service. A nearby rancher had discovered a strange object poking out of the ground. They wanted Schmidt to take a look.
"One of the very first bones that we saw in the rock was this long cylindrical bone," Schmidt told St. Louis Public Radio. "The first thing that came out of our mouths was, 'That kind of looks like the horn of a triceratops.'"
After authorities gave the go-ahead, Schmidt and a small group of students returned this summer and spent nearly every day of June and July excavating the skull.
Credit: David Schmidt / Westminster College
"We had to be really careful," Schmidt told St. Louis Public Radio. "We couldn't disturb anything at all, because at that point, it was under law enforcement investigation. They were telling us, 'Don't even make footprints,' and I was thinking, 'How are we supposed to do that?'"
Another difficulty was the mammoth size of the skull: about 7 feet long and more than 3,000 pounds. (For context, the largest triceratops skull ever unearthed was about 8.2 feet long.) The skull of Schmidt's dinosaur was likely a Triceratops prorsus, one of two species of triceratops that roamed what's now North America about 66 million years ago.
Credit: David Schmidt / Westminster College
The triceratops was an herbivore, but it was also a favorite meal of the Tyrannosaurus rex. That probably explains why the Dakotas contain many scattered triceratops bone fragments, and, less commonly, complete bones and skulls. In summer 2019, for example, a separate team on a dig in North Dakota made headlines after unearthing a complete triceratops skull that measured five feet in length.
Michael Kjelland, a biology professor who participated in that excavation, said digging up the dinosaur was like completing a "multi-piece, 3-D jigsaw puzzle" that required "engineering that rivaled SpaceX," he jokingly told the New York Times.
Morrison Formation in Colorado
James St. John via Flickr
The Badlands aren't the only spot in North America where paleontologists have found dinosaurs. In the 1870s, Colorado and Wyoming became the first sites of dinosaur discoveries in the U.S., ushering in an era of public fascination with the prehistoric creatures — and a competitive rush to unearth them.
Since, dinosaur bones have been found in 35 states. One of the most fruitful locations for paleontologists has been the Morrison formation, a sequence of Upper Jurassic sedimentary rock that stretches under the Western part of the country. Discovered here were species like Camarasaurus, Diplodocus, Apatosaurus, Stegosaurus, and Allosaurus, to name a few.
Triceratops illustration
| Credit: Nobu Tamura/Wikimedia Commons |
As for "Shady" (the nickname of the South Dakota triceratops), Schmidt and his team have safely transported it to the Westminster campus. They hope to raise funds for restoration, and to return to South Dakota in search of more bones that once belonged to the triceratops.
Studying dinosaurs helps scientists gain a more complete understanding of our evolution, illuminating a through-line that extends from "deep time" to present day. For scientists like Schmidt, there's also the simple joy of coming to face-to-face with a lost world.
"You dream about these kinds of moments when you're a kid," Schmidt told St. Louis Public Radio. "You don't ever think that these things will ever happen."
The following is an adapted excerpt from the book What's the Use? It is reprinted with permission of the author and Hachette Book Group.
What is mathematics for?
What is it doing for us, in our daily lives?
Not so long ago, there were easy answers to these questions. The typical citizen used basic arithmetic all the time, if only to check the bill when shopping. Carpenters needed to know elementary geometry. Surveyors and navigators needed trigonometry as well. Engineering required expertise in calculus.
Today, things are different. The supermarket checkout totals the bill, sorts out the special meal deal, adds the sales tax. We listen to the beeps as the laser scans the barcodes, and as long as the beeps match the goods, we assume the electronic gizmos know what they are doing. Many professions still rely on extensive mathematical knowledge, but even there, we have outsourced most of the mathematics to electronic devices with built-in algorithms.
My subject is conspicuous by its absence. The elephant isn't even in the room.
It would be easy to conclude that mathematics has become outdated and obsolete, but that view is mistaken. Without mathematics, today's world would fall apart. As evidence, I am going to show you applications to politics, the law, kidney transplants, supermarket delivery schedules, Internet security, movie special effects, and making springs. We will see how mathematics plays an essential role in medical scanners, digital photography, fiber broadband, and satellite navigation. How it helps us predict the effects of climate change; how it can protect us against terrorists and Internet hackers.
Remarkably, many of these applications rely on mathematics that originated for totally different reasons, often just the sheer fascination of following your nose. While researching this book, I was repeatedly surprised when I came across uses of my subject that I had never dreamed existed. Often, they exploited topics that I would not have expected to have practical applications, like space-filling curves, quaternions, and topology.
Mathematics is a boundless, hugely creative system of ideas and methods. It lies just beneath the surface of the transformative technologies that are making the twenty-first century totally different from any previous era — video games, international air travel, satellite communications, computers, the Internet, mobile phones. Scratch an iPhone, and you will see the bright glint of mathematics.
Please don't take that literally.
There is a tendency to assume that computers, with their almost miraculous abilities, are making mathematicians, indeed mathematics itself, obsolete. But computers no more displace mathematicians than the microscope displaced biologists. Computers change the way we go about doing mathematics, but mostly they relieve us of the tedious bits. They give us time to think, they help us search for patterns, and they add a powerful new weapon to help advance the subject more rapidly and more effectively.
In fact, a major reason why mathematics is becoming ever more essential is the ubiquity of cheap, powerful computers. Their rise has opened up new opportunities to apply mathematics to real-world issues. Methods that were hitherto impractical, because they needed too many calculations, have now become routine. The greatest mathematicians of the pencil-and-paper era would have flung up their hands in despair at any method requiring a billion calculations. Today, we routinely use such methods, because we have technology that can do the sums in a split second. Mathematicians have long been at the forefront of the computer revolution — along with countless other professions, I hasten to add. Think of George Boole, who pioneered the symbolic logic that forms the basis of current computer architecture. Think of Alan Turing, and his universal Turing machine, a mathematical system that can compute anything that is computable. Think of Muhammad al-Khwarizmi, whose algebra text of 820 AD emphasized the role of systematic computational procedures, now named after him: algorithms.
Most of the algorithms that give computers their impressive abilities are firmly based on mathematics. Many of the techniques concerned have been taken "off the shelf" from the existing store of mathematical ideas, such as Google's PageRank algorithm, which quantifies how important a website is and founded a multi-billion-dollar industry. Even the snazziest deep learning algorithm in artificial intelligence uses tried and tested mathematical concepts such as matrices and weighted graphs. A task as prosaic as searching a document for a particular string of letters involves, in one common method at least, a mathematical gadget called a finite-state automaton.
The involvement of mathematics in these exciting developments tends to get lost. So next time the media propel some miraculous new ability of computers to center stage, bear in mind that hiding in the wings there will be a lot of mathematics, and a lot of engineering, physics, chemistry, and psychology as well, and that without the support of this hidden cast of helpers, the digital superstar would be unable to strut its stuff in the spotlight.
The importance of mathematics in today's world is easily underestimated because nearly all of it goes on behind the scenes. Walk along a city street, and you are overwhelmed by signs proclaiming the daily importance of banks, greengrocers, supermarkets, fashion outlets, car repairs, lawyers, fast food, antiques, charities, and a thousand other activities and professions. You do not find a brass plaque announcing the presence of a consulting mathematician. Supermarkets do not sell you mathematics in a can.
Dig a little deeper, however, and the importance of mathematics quickly becomes apparent. The mathematical equations of aerodynamics are vital to aircraft design. Navigation depends on trigonometry. The way we use it today is different from how Christopher Columbus used it, because we embody the mathematics in electronic devices instead of pen, ink, and navigation tables, but the underlying principles are much the same. The development of new medicines relies on statistics to make sure the drugs are safe and effective. Satellite communications depend on a deep understanding of orbital dynamics. Weather forecasting requires the solution of equations for how the atmosphere moves, how much moisture it contains, how warm or cold it is, and how all of those features interact. There are thousands of other examples. We do not notice they involve mathematics, because we do not need to know that to benefit from the results.
