When it comes to smelling pretty, petunias are pretty pushy.

Instead of just letting scent compounds waft into the air, the plants use a particular molecule called a transporter protein to help move the compounds along, a new study found. The results, published June 30 in Science, could help researchers genetically engineer many kinds of plants both to attract pollinators and to repel pests and plant eaters.

“These researchers have been pursuing this transporter protein for a while,” says David Clark, an expert in horticultural biotechnology and genetics at the University of Florida in Gainesville. “Now they’ve got it. And the implications could be big.”
Plants use scents to communicate (SN: 7/27/02, p. 56). The scent compounds can attract insects and other organisms that spread pollen and help plants reproduce, or can repel pests and plant-eating animals. The proteins found in the new study could be used to dial the amount of scent up or down so that plants can attract more pollinators or better protect themselves. Currently unscented plants could be engineered to smell, too, giving them a better shot at reproduction and survival, Clark says.
Plants get their scents from volatile organic compounds, which easily turn into gases at ambient temperatures. Petunias get their sweet smell from a mix of benzaldehyde, the same compound that gives cherries and almonds their fruity, nutty scent, and phenylpropanoids, often used in perfumes.

But nice smells have a trade-off: If these volatile compounds build up inside a plant, they can damage the plant’s cells.
About two years ago, study coauthor Joshua Widhalm, a horticulturist at Purdue University in West Lafayette, Ind., and colleagues used computer simulations to look at the way petunias’ scent compounds moved. The results showed that the compounds can’t move out of cells fast enough on their own to avoid damaging the plant. So the researchers hypothesized that something must be shuttling the compounds out.

In the new study, led by Purdue biochemist Natalia Dudareva, the team looked for genetic changes as the plant developed from its budding stage, which had the lowest levels of volatile organic compounds, to its flower-opening stage, with the highest levels. As flowers opened and scent levels peaked, the gene PhABCG1 went into overdrive; levels of the protein that it makes jumped to more than 100 times higher than during the budding stage, the researchers report.

The team then genetically engineered petunias to produce 70 to 80 percent less of the PhABCG1 protein. Compared with regular petunias, the engineered ones released around half as much of the scent compounds, with levels inside the plant’s cells building to double or more the normal levels. Images of the cells show that the accumulation led to deterioration of cell membranes.

A lot of work has been done to identify the genes and proteins that generate scent compounds, says Clark. But this appears to be the first study to have identified a transporter protein to shuttle those compounds out of the cell. “That’s a big deal,” he says.

Galaxies may grow by swiping gas from their neighbors.

New simulations suggest that nearly half the matter in the Milky Way may have been siphoned from the gas of other galaxies. That gas provides the raw material that galaxies use to build their bulk. The finding, scheduled to appear in the Monthly Notices of the Royal Astronomical Society, reveals a new, unexpected way for galaxies to acquire matter and could give clues to how they evolve.
“These simulations show a huge amount of interaction among galaxies, a huge dance that’s going on,” says astronomer Romeel Davé of the University of Edinburgh. That dance, and the subsequent exchange of atoms, could be what establishes a galaxy’s character — whether it’s small or big, elliptical or spiral, quiet or bursting with star formation. If the simulation results are confirmed with observations, it could be a major advancement in understanding galaxy formation, Davé says.

It makes sense that much of the material in one galaxy actually came from other galaxies, says study coauthor Claude-André Faucher-Giguère, a theoretical astrophysicist at Northwestern University in Evanston, Ill. “Still, the result was really unexpected,” he says.

Astronomers thought galaxies got their matter in two main ways. First, atoms clumped together to form stars and then galaxies, not long after the Big Bang about 13.8 billion years ago. Then some of those atoms were eventually ejected by supernovas but rained back onto the same galaxy, recycling the gas again and again.

The new simulations showed a third way galaxies could score gas. Powerful supernova explosions would eject atoms, in the form of gas, far from their home galaxies into intergalactic space. Those atoms would then travel through space, pushed toward other galaxies by galactic winds that move at several hundred kilometers per second. When the particles neared a galaxy’s gravitational pull, they would get sucked in, where they would serve as the basis for stars, planets, dust and other material in their new galactic home. Still, this exchange of atoms is extremely difficult to spot in space because the gas atoms, don’t give off light like stars do.
Faucher-Giguère and colleagues spotted the exchange in computer simulations that show how galaxies formed just after the Big Bang and how they have evolved over time. The team tracked gas atoms as they moved through the model universe, formed stars and then were ejected from galaxies as those stars exploded.

In the simulations, up to half of the atoms in large galaxies were pulled in from other galaxies. Because more massive galaxies have more gravity, they tended to pull atoms from the ejected material of small galaxies. The exchange appears to take billions of years as atoms travel the vast space between galaxies, the team notes.

“It’s that not surprising to see a galaxy kick out matter, which is then pulled in by other galaxies,” Davé says. What is surprising, he says, is the amount of material that’s transferred. Before seeing the simulations, he would have guessed that about 5 percent of gas was transferred among galaxies this way. “To see that it is up to 50 percent is pretty remarkable,” he says.

Already, astronomers are searching for evidence of this material-swapping behavior among galaxies. Faucher-Giguère and colleagues, working with researchers using the Hubble Space Telescope, hope to observe intergalactic transfer of gas among galaxies soon.

Pluto has no rings — New Horizons triple-checked. An exhaustive search for rings and dust particles around the dwarf planet before, during and after the spacecraft flew past Pluto in 2015 has come up empty.

“It’s a very long paper to say we didn’t find anything,” says team member Tod Lauer of the analysis, posted online September 23 at arXiv.org. But the nonresult could help scientists understand the contents of the outer solar system — and help plan New Horizons’ next encounter. The spacecraft is now on a course to a space rock in the Kuiper Belt, another 1.5 billion kilometers past Pluto.
Before New Horizons arrived at Pluto, the possible existence of rings was an urgent matter of safety. Hitting a particle as small as a sand grain could have damaged the spacecraft.

Searches with the Hubble Space Telescope in 2011 and 2012 turned up two previously unknown moons orbiting Pluto — Kerberos and Styx (SN: 11/28/15, p. 14) — and zero rings. Even so, many researchers expected to encounter rings, or at least some debris. The four outer planets in the solar system have rings, as do other small bodies in the solar system, like the tiny planetoid 10199 Chariklo (SN: 5/3/14, p. 10). And some studies suggest that Pluto probably had rings at one point in its past, left over from the collision that formed its largest moon, Charon.

Nine weeks before New Horizons’ closest approach to Pluto, a team jokingly called the “crow’s nest” acted much like a ship’s lookout for potential hazards, says Lauer, an astronomer with the National Optical Astronomy Observatory in Tucson, Ariz. The group examined images taken with the spacecraft’s Long Range Reconnaissance Imager camera, looking for ring particles reflecting sunlight or spots that moved against a starry background from one set of images to the next. Nothing turned up.

The team declared the spacecraft’s trajectory safe, and New Horizons flew sailed safely past Pluto on July 14, 2015 (SN Online: 7/15/15). After the flyby, the team turned New Horizons around to look back at Pluto, and towards the sun. This was a much better position to look for rings, as dust particles would pop into view when backlit by the sun like motes of dust in the light from a window.

“If you really want to know for sure whether there’s any dust there, the viewing geometries where you’re looking past the dust with the sun in the background, that’s the gold standard,” says Matthew Tiscareno of the SETI Institute in Mountain View, Calif., who studied Saturn’s rings with the Cassini spacecraft but was not involved in New Horizons.
It took the better part of a year for all the data from New Horizons to return to Earth, and several months after that to analyze it, but the team is now ready to call it: The rings really aren’t there — or at least they’re too diffuse to see.

That’s somewhat surprising, Lauer says. But the chaotic gravity of Pluto’s family of moons might make it too hard for rings to find stable orbits. Or the slight pressure generated by light particles streaming from the sun could constantly blow would-be ring particles away.

It’s also possible there just wasn’t that much dust there to begin with. New Horizons saw fewer craters on Pluto and Charon than expected, which could mean there are fewer small bodies at that distance from the sun smacking into Pluto and its moons and kicking up dust.

That could be good news for New Horizons’ next act. After five months in hibernation, the spacecraft woke up on September 11 and has set its sights on a smaller, weirder and more distant object: a space rock about 30 kilometers long called 2014 MU69 (SN Online: 7/20/17). Initial observations suggest it might be a double object, with two bodies orbiting closely or touching lightly.

New Horizons will fly past MU69 on January 1, 2019. In the meantime, the team is looking for hazards along the route. “We’re going to do a similar effort to what we did with Pluto,” Lauer says. “We’re going to get in the crow’s nest and get out our binoculars, as it were, and see if we’re going to be okay.”

When you’re pregnant, especially for the first time, you have to make a lot of decisions. Will coffee remain a part of your life? Where are you going to give birth? What are you going to name the baby? What values will you teach him? Do you really need a baby spa bathtub?

Before my first daughter arrived, an instructor at a birth class threw me a curveball: Was I planning on banking my baby’s umbilical cord blood?
For much of pregnancy, the umbilical cord is the lifeline of a fetus, tethering it to the placenta. Snaking through the nearly 2-feet-long cord, there’s a vein ferrying nutrients and oxygen from mom’s blood (via the placenta), plus two arteries carrying oxygen- and nutrient-depleted blood from the fetus back to mom. Because mother’s blood and fetal blood don’t actually mix much, the blood in the placenta and umbilical cord at birth belongs mainly to the fetus.

That fetal blood holds all sorts of interesting — and potentially therapeutic — cells and molecules. This realization has, in some cases, changed the way the umbilical cord and placenta are handled during birth. Instead of tossing it aside, some doctors, scientists and parents are choosing to bank this fetal blood — harvesting it from the baby’s umbilical cord and placenta, freezing it and storing it away for later.

Proponents of cord blood banking are convinced that instead of being medical waste, the fetal cells within are biological gold. In this post, and the two that follow, I’ll take a look at the evidence for those claims, and sort through some of the questions that arise as parents consider whether to bank their baby’s cord blood.

Back in the 1980s, umbilical cord blood caught the attention of researchers who suspected that the often-discarded tissue could be a valuable source of shape-shifting stem cells. These cells, which can become several different types of blood cells, are similar to the specialized stem cells found in bone marrow that can churn out new blood cells. Such stem cells are found in adult blood, too, but not as abundantly.
In 1988, a 5-year-old named Matthew with a rare type of anemia received umbilical cord blood cells from his newborn sister, who didn’t have the disease. That transfer, called an umbilical cord blood transplant, worked, and the boy was soon free of the disease.

At the time, researchers didn’t know much about the properties of the cells found in umbilical cord blood. But research has zoomed forward, illuminating more about the contents of this young blood.

Of particular interest are the flexible hematopoietic stem cells important in that initial transplant. In certain cases, transplanting these cells might be able to reboot a person’s body and get rid of a disease-related defect. Cord blood transplants are similar to bone marrow transplants. A person with leukemia, for instance, might have his own cancerous blood cells wiped out with chemotherapy and radiation. Healthy, non-cancerous stem cells from a donor can then repopulate the blood.

Extracting stem cells from bone marrow requires surgery under anesthesia; extracting them from the blood requires taking a drug to stimulate their production. And in order to work, these stem cell donations need to come from a person who carries a similar pattern of proteins on the outsides of his or her cells, a molecular calling card known as HLA type. Stem cells found in cord blood don’t need to be as closely matched to work. Because these cells are so flexible, there’s more wiggle room between donor and recipient. That’s particularly good news for people of certain ethnic minorities who often have trouble finding matched stem cell transplant donors.

Hard numbers are tricky to pin down, but between that first transplant in 1988 and 2015, an estimated 35,000 umbilical cord blood transplants had been performed globally. That number includes people treated for leukemia and other types of cancer, blood disorders and immune diseases. And the utility of umbilical cord cells may stretch well beyond the disorders that the cells are currently being used for. “If you read the literature, it’s pretty exciting,” says pediatrician and immunologist William Shearer of Baylor College of Medicine and Texas Children’s Hospital.

Some researchers suspect that umbilical cord blood contains other cells that may have therapeutic effects beyond the blood. Specialized immune cells may be able to tweak brain function, for instance. Trials around the world are studying umbilical cord blood’s capabilities in a wide range of diseases (see Table 2 here): Cerebral palsy, autism, diabetes and lupus are currently under investigation. The cells are even being tested for an ameliorating role in Alzheimer’s disease and other neurodegenerative conditions.

After injections with their own umbilical cord blood, 63 children with cerebral palsy improved on motor skills, on average. And a clinical trial to see whether cord blood transplants improve symptoms of children with autism spectrum disorder should wrap up in the summer of 2018, says pediatric researcher and clinician Joanne Kurtzberg of Duke University, who helped establish a not-for-profit umbilical cord bank in North Carolina. (A small but optimistic pilot study has already been completed.)

The potential powers of these cells have researchers excited. But what that scientific hope means for expectant parents facing decisions about cord blood banking is far from clear. For all of the promise, there are lots of reasons why umbilical cord cells may turn out to be less useful than thought. Read my next post for more about these potential drawbacks.

Greenland is melting rapidly, but some glaciers are disappearing faster than others. A new map of the surrounding seafloor helps explain why: Many of the fastest-melting glaciers sit atop deep fjords that allow Atlantic Ocean water to melt them from below.

Researchers led by glaciologist Romain Millan of the University of California, Irvine analyzed new oceanographic and topographic data for 20 major glaciers within 10 fjords in southeast Greenland. The mapping revealed that some fjords are several hundred meters deeper than simulations of the bathymetry suggested, the researchers report online March 25 in Geophysical Research Letters. These troughs allow warmer and saltier waters from deeper in the ocean to reach the glaciers and erode them.
Other glaciers are protected by shallow sills, or raised seafloor ledges. These sills act as barriers to the deep, warm water, the new seafloor maps show. The researchers compared their findings with observations of glacier melt from 1930 to 2017, and found that the fastest-melting glaciers tended to be those more exposed to melting from below.
The study uses data from two NASA missions — Operation IceBridge, which measures ice thickness and gravity from aircraft, and Oceans Melting Greenland, or OMG, which uses sonar and gravity instruments to map the shape and depth of the seafloor close to the ice front. The OMG mission also involves dropping hundreds of probes into the ocean each year to measure temperature and salinity at different depths.
Scientists have long suspected Greenland’s melting may be accelerated by the ocean (SN Online: 7/6/11), but needed data on fjord depth and glacier thickness to prove it.

The high-resolution OMG datasets, in particular, reveal bumps and troughs in the seafloor that were previously unknown, says glaciologist Andy Aschwanden at the University of Alaska Fairbanks, who was not involved with the study. “Those small details can make quite a difference to when a glacier will retreat.”

Just a few tweaks to a bacterial enzyme make it a lean, mean plastic-destroying machine.

One type of plastic, polyethylene terephthalate, or PET, is widely used in polyester clothing and disposable bottles and is notoriously persistent in landfills. In 2016, Japanese scientists identified a new species of bacteria, Ideonella sakaiensis, which has a specialized enzyme that can naturally break down PET.

Now, an international team of researchers studying the enzyme’s structure has created a variant that’s even more efficient at gobbling plastic, the team reports April 17 in Proceedings of the National Academy of Sciences.

The scientists used a technique called X-ray crystallography to examine the enzyme’s structure for clues to its plastic-killing abilities. Then, they genetically tweaked the enzyme to create small variations in the structure, and tested those versions for PET-degrading performance. Some changes made the enzyme work even better. Both the original version and the mutated versions could break down both PET and another, newer bio-based plastic called PEF, short for polyethylene-2,5-furandicarboxylate. With a little more engineering, these enzymes could someday feast at landfills.

Ancient surgeons may have practiced dangerous skull-opening procedures on cows before operating on people.

A previously excavated cow skull from a roughly 5,400- to 5,000-year-old settlement in France contains a surgically created hole on the right side, a new study finds. No signs of bone healing, which start several days after an injury, appear around the opening. One or more people may have rehearsed surgical techniques on a dead cow, or may have tried unsuccessfully to save a sick cow’s life in what would be the oldest known case of veterinary surgery, researchers conclude online April 19 in Scientific Reports.

Evidence of skull surgery on humans, whether for medical or ritual reasons, goes back about 11,000 years (SN: 5/28/16, p. 12). Ancient surgeons needed to know how and where to scrape away bone without harming brain tissue and blood vessels. So practicing bone removal on cows or other animals is plausible.

The ancient cow’s skull opening, shaped almost in a square and framed by scrape marks, resembles two instances of human skull surgery from around the same time in France, say biological anthropologists Fernando Ramirez Rozzi of CNRS in Montrouge, France, and Alain Froment of IRD-Museum of Man in Paris. Microscopic and X-ray analyses found no fractures or splintered bone that would have resulted from goring by another cow’s horn. No damage typical of someone having struck the cow’s head with a club or other weapon appeared, either.

Club-wielding assailants struck the Scandinavian settlement with devastating violence, slaughtering at least 26 people and leaving the bodies where they fell. There, the bodies lay for 1,500 years until recovered recently by archaeologists analyzing clues about the Iron Age massacre.

It’s unclear why the seaside ringfort of Sandby borg, on the Baltic Sea island of Ӧland, was targeted at a time of political turmoil following the Roman Empire’s fall in Western Europe. Adults, teenagers and children died suddenly and brutally — their skeletons showing bones fractured by clubs, but no defensive wounds, say archaeologist Clara Alfsdotter of Bohuslӓns Museum in Udevalla, Sweden, and her colleagues. When the slaughter was over, the attackers left the sheep and other animals to starve and the valuables untouched, the scientists report in the April Antiquity. No one came back to bury the dead.
That’s somewhat unusual: At most other excavated battlefield and massacre sites in Europe, bodies have been found in mass graves ( SN: 1/23/16, p. 7). However, 67 farming villagers slaughtered around 7,200 years ago at Austria’s Asparn-Schletz site were also left in place. Circumstances surrounding the attacks on Asparn-Schletz and Sandby borg are poorly understood, making it difficult to compare the two events, says anthropologist Bruno Boulestin of the University of Bordeaux in France, who did not participate in the excavation.
The bones from Sandby borg have yet to undergo radiocarbon dating, making it impossible to say precisely when the massacre occurred, says archaeologist Ian Armit of the University of Bradford in England, who did not participate in the Sandby borg research. But the researchers suspect the killing happened after 476, when the fall of the Western Roman Empire left a power vacuum and power struggles broke out across parts of Europe and southern Scandinavia. Sandby borg’s attackers may have installed themselves as the new local rulers, the team suggests.

“It was not the killing that was the point, but the statement toward those witnessing it from a distance that ‘if you mess with us, this is what happens,’” says study coauthor Ludvig Papmehl-Dufay of Kalmar County Museum in Sweden.

Sandby borg, spanning roughly 5,000 square meters contained by an eroded oval stone wall, has been a center for archaeological excavations since 2011. Aerial photographs and ground surveys have revealed stone structures buried inside the ringfort off Sweden’s southeast coast. Investigators have located 53 houses, some within a central block circled by a street. By 2016, two houses had been fully excavated and seven others had undergone some investigation. Inside, researchers found gilded silver brooches, glass beads and silver bell pendants, in styles suggesting the fort was occupied in the late 400s.
In one house, the skeletons of nine individuals of various ages were found. Their positions suggested they had been surprised by the attack, say Alfsdotter, Papmehl-Dufay and coauthor Helena Victor, also of Kalmar County Museum. One teenage boy appears to have fallen backward over an adult victim. Two corpses showed evidence of being partially burned, suggesting the attackers tried unsuccessfully to set the structure on fire or that a fire accidentally broke out. A tiny half skeleton from a herring lay next to the fireplace, adding support to the theory that the attackers left quickly without touching or eating anything. A pile of lamb skeletons stacked in the corner and showing signs of recent slaughter suggests the attack occurred sometime between late spring and early fall, the researchers say.

Scientists are working on radiocarbon dating the Sandby borg skeletons as the annual excavations continue, Papmehl-Dufay says. With more than 90 percent of the ringfort settlement yet to be excavated, there are likely more clues to the killing to be found.

Richard Feynman was a curious character.

He advertised as much in the subtitle of his autobiography, Surely You’re Joking, Mr. Feynman!: Adventures of a Curious Character. Everybody knew that, in many respects, Feynman was an oddball.

But he was curious in every other sense of the word as well. His curiosity about nature, about how the world works, led to a Nobel Prize in physics and a legendary reputation, both among physicists and the public at large.
Feynman was born 100 years ago May 11. It’s an anniversary inspiring much celebration in the physics world. Feynman was one of the last great physicist celebrities, universally acknowledged as a genius who stood out even from other geniuses.

In 1997 I interviewed Nobel laureate Hans Bethe, a Cornell University physicist who worked with Feynman during World War II on the atomic bomb project at Los Alamos (and later on the Cornell faculty). “Normal” geniuses, Bethe said, did things much better than other people but you could figure out how they did it. And then there were magicians. “Feynman was a magician. I could not imagine how he got his ideas,” Bethe told me. “He was a phenomenon. Feynman certainly was the most original physicist I have seen in my life, and I have seen lots of them.”

Apart from his brilliance as a physicist, Feynman was also known for his skill at playing the bongo drums and cracking safes. Public acclaim came after he served on the presidential commission investigating the explosion of the space shuttle Challenger. In a dramatic moment during a hearing about that disaster, he dipped material from an O-ring (a crucial seal on the shuttle’s rockets) into icy water, demonstrating that an O-ring would not have remained flexible at the launch-time temperature.
His autobiography had already become a best seller, so Feynman was well-known when he died in February 1988.

When I heard of Feynman’s death, I called John Wheeler, Feynman’s doctoral adviser at Princeton University before World War II.

“I felt very lucky to have him as my graduate student,” said Wheeler, who died in 2008. “There was an immense vitality about Feynman. He was interested in all kinds of problems.”

Feynman’s curiosity was not satisfied merely by being told the solution to a problem, though.

“If you said you had the answer to something, he wouldn’t let you tell it,” Wheeler said. “He had to stand on his head and pace up and down and figure out the answer for himself. It was his way of keeping the ability to make headway into brand new frontiers.”

Feynman found fascination in all sorts of things, some profound, some trivial. In his autobiography, he revealed that he spent a lot of time analyzing ant trails. He sometimes entertained Wheeler’s children by tossing tin cans into the air and then explaining how the way the can turned revealed whether the contents were solid or liquid.

Curiosity of that type was instrumental in the work that led to his Nobel Prize. While eating in the Cornell cafeteria, Feynman noticed someone tossing a plate, kind of like a Frisbee. As the plate flew by, Feynman noticed that the Cornell medallion on the plate was rotating more rapidly than the plate was wobbling. He performed some calculations and showed that the medallion’s rotation rate should be precisely twice the rate of the wobbling. He then perceived an analogy to a problem he had been investigating relating to the motion of electrons. The wobbling plate turned out to provide the clue he needed to develop a new version of the theory of quantum electrodynamics.

“The whole business that I got the Nobel Prize for came from that piddling around with the wobbling plate,” he wrote in his autobiography.

It was not curiosity alone that made Feynman a legend. His approach to physics and life incorporated a willful disdain for authority. He regularly disregarded bureaucratic rules, ignored expert opinion and was willing to fearlessly criticize the most eminent of other scientists.

During his time at Los Alamos, for instance, he encountered Niels Bohr, the foremost atomic physicist of the era. Other physicists held Bohr in awe. “Even to the big shot guys,” Feynman recalled, “Bohr was a great god.” During a meeting in which the “big shots” deferred to Bohr, Feynman kept pestering him with questions. Before the next meeting, Bohr called Feynman in to talk without the big shots. Bohr’s son (and assistant) later explained why. “He’s the only guy who’s not afraid of me, and will say when I’ve got a crazy idea,” Niels had said to his son. “So next time when we want to discuss ideas, we’re not going to be able to do it with these guys who say everything is yes, yes, Dr. Bohr. Get that guy and we’ll talk with him first.”

Feynman knew that he sometimes made mistakes. Once he foolishly even read some papers by experts that turned out to be wrong, retarding his work on understanding the form of radioactivity known as beta decay. He vowed never to make the mistake of listening to “experts” again.

“Of course,” he ended one chapter of his autobiography, “you only live one life, and you make all your mistakes, and learn what not to do, and that’s the end of you.”

You would be forgiven for thinking that real numbers are, in fact, real — the word is right there in the name. But physicist Nicolas Gisin doesn’t think so.

He’s not questioning the mathematical concept of a real number. The term refers to a number that isn’t imaginary: It has no factor of i, the square root of negative one. Instead, Gisin, of the University of Geneva, debates the physical reality of real numbers: Do they appropriately represent nature? Physicists regularly use real numbers to describe the world: velocities, positions, temperatures, energies. But is that description really correct?
Gisin — known for his work on the foundations and applications of quantum mechanics — takes issue with real numbers that consist of a never-ending string of digits with no discernable pattern and that can’t be calculated by a computer. Such numbers (for example, 1.9801545341073… and so on) contain an infinite amount of information: You could imagine encoding in those digits the answers to every fathomable question in the English language — and more.

But to represent the world, real numbers shouldn’t contain unlimited information, Gisin says, because, “in a finite volume of space you will never have an infinite amount of information.”

Instead, Gisin argues March 19 on arXiv.org, only a certain number of digits of real numbers have physical meaning. After some number of digits, for example, the thousandth digit, or maybe even the billionth digit, their values are essentially random.

Most physicists don’t give much thought to philosophical puzzles like this one, but Gisin’s argument has big implications for the seemingly unrelated concept of free will. Standard classical physics, the branch of physics that governs the everyday, human-sized world, leaves no room for free will. Given the appropriate equations and the conditions of the world, classical physics says, everything can, in principle, be calculated, and therefore, predetermined.
But if the world is described by numbers that have randomness baked into them, as Gisin suggests, that would knock classical physics from its deterministic perch. That would mean that the behavior of the universe — and everything in it — can’t be predetermined, Gisin says. “There really is room for creativity.”