Mini brains may wrinkle and fold just like ours

PHILADELPHIA — Flat brains growing on microscope slides may have revealed a new wrinkle in the story of how the brain folds.

Cells inside the brains contract, while cells on the outside grow and push outward, researchers at the Weizmann Institute of Science in Rehovot, Israel, discovered from working with the lab-grown brains, or organoids. This push and pull results in folds in the organoids similar to those found in full-size brains. Orly Reiner reported the results December 5 at the joint meeting of the American Society for Cell Biology and the European Molecular Biology Organization.
Reiner and her colleagues sandwiched human brain stem cells between a glass microscope slide and a porous membrane. The apparatus allowed the cells access to nutrients and oxygen while giving the researchers a peek at how the organoids grew. The cells formed layered sheets that closed up at the edges, making the organoids resemble pita bread, Reiner said. Wrinkles began to form in the outer layers of the organoids about six days after the mini brains started growing.

These brain organoids may help explain why people with lissencephaly — a rare brain malformation in which the ridges and folds are missing — have smooth brains. The researchers used the CRISPR/Cas9 gene-editing system to make a mutation in the LIS1 gene. People with lissencephaly often have mutations in that gene. Cells carrying the mutation didn’t contract or move normally, the team found.

Reiner and her colleagues aren’t the first to propose the push-pull idea for how brains fold. But the researchers were able to show the concept at work in their experimental system, says biophysicist Xavier Trepat of the Institute for Bioengineering of Catalonia in Barcelona, who was not involved in the study. “They really were able to reproduce the shape of what we all imagine the brain should look like,” he says. “It’s not a brain, but they see structures that look like it.”

U.S. religion is increasingly polarized

There’s both inspiring and troubling news for holiday worshippers.

Unlike other historically Christian Western nations, the United States is not losing its religion, say sociologists Landon Schnabel of Indiana University Bloomington and Sean Bock of Harvard University. But America is becoming as polarized religiously as it is politically, the researchers report online November 27 in Sociological Science.

Intense forms of religion, such as Christian evangelicalism, have maintained their popularity for nearly 30 years, Schnabel and Bock find after analyzing almost 30 years of U.S. survey data. At the same time, moderate forms of religion, such as mainline Protestantism, have consistently lost followers.
Religious moderates’ exodus from their churches stems partly from a growing link between religion and conservative politics, exemplified by the rise of the religious right in the late 1980s, the researchers suspect. Political liberals and moderates who already felt lukewarm toward the religion of their parents increasingly report identifying with no organized religion, especially if leaders of their childhood churches have taken conservative stances on social issues. Many Americans still report that they believe in God and pray, so they haven’t turned to atheism, the scientists say.

Population trends also favor intense forms of religion, Schnabel holds. Mainline Protestantism’s decline from 35 percent of the U.S. population in 1972 — about 73.5 million people — to 12 percent in 2016 — nearly 39 million people — reflects low fertility rates among these Protestants and limited numbers of new adherents from immigration and conversion. Opposite trends among U.S. evangelicals helped their form of intense Christianity surge from 18 percent of the population in 1972 to a steady level of about 28 percent from 1989 to 2016.

“More moderate forms of organized religion could become increasingly irrelevant in the United States,” Schnabel says.
The new findings play into an academic debate about the fate of religion in modern societies. Some scholars argue that in wealthy nations marked by scientific advances, religion inevitably withers. National surveys in 13 other Western, historically Christian nations show a general weakening of religious beliefs, even among intense believers, since 1991, the researchers find. But Schnabel and Bock are among those who view the United States as an exception where intense religion holds steady and even many of those leaving churches keep their faith.

The researchers examined data from nationally representative surveys on religion and other topics conducted from 1989 to 2016 by the General Social Survey, or GSS, a project of the National Opinion Research Center at the University of Chicago. GSS surveys include approximately 1,500 people annually.

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The proportion of the U.S. population citing strong ties to any religion held steady at around 36 percent during the study period. But the share of adults identifying themselves as religiously unaffiliated rose from around 9 percent to around 20 percent of the population, the researchers report. In another sign of loosening religious ties, those who never attended religious services rose from around 14 percent to around 25 percent of the population. Occasional attendance dropped from about 80 percent to about 70 percent.

Still, those who rarely or never prayed remained at about 24 percent of the population from 1989 to 2016. People who prayed several times a day rose from around 24 percent to about 30 percent of the total.

A belief in the Bible as God’s literal word held steady at roughly one-third of Americans. A view of the Bible as inspired by a higher power but not literal fell slightly to just under half of the population. Those tagging the Bible as a book of fables rose from around 15 percent to around 22 percent.

The new findings underscore the growing polarization of U.S. religion, say Michael Hout of New York University and Claude Fischer of the University of California, Berkeley. In a 2014 report based on GSS data, the two sociologists found that most political liberals and some political moderates who weakly identified with their parents’ religion have increasingly said that they prefer no particular religion. That trend was most pronounced for those reporting that the church they grew up with had become an advocate of politically conservative positions. Many of those people expressed a qualified belief in God, endorsing neither atheism nor absolute certainty in a higher power’s existence. Political conservatives, including those who seldom attended services or had doubts about church doctrine, had no complaints about religious leaders’ conservative political pronouncements.

Members of the millennial generation born since 1990 report low levels of religious involvement regardless of their politics, Hout adds. Millennials are skeptical of institutions in general although most still believe in God, he says. “Millennials are more comfortable with do-it-yourself religion than none at all.”

Sociologists David Voas of University College London and Mark Chaves of Duke University disagree. Millennials are part of a larger U.S. trend in which each successive generation over nearly the last century has reported slightly less intensity of religious belief than the one before, Voas and Chaves reported in a 2016 analysis of GSS data. For instance, in 2014, only 45 percent of U.S. adults ages 18 to 30 had no doubts that God exists versus 68 percent of those age 65 or over.

“The proportion of intensely religious Americans is being eroded, albeit very slowly,” Voas contends.

The sun’s outer atmosphere is far more complex than previously thought

NEW ORLEANS — Despite its smooth appearance, the sun’s wispy outer atmosphere is surprisingly full of knots, whorls and blobs.

Newly analyzed observations from NASA’s STEREO spacecraft show that the sun’s outer corona is just as complicated as the highly structured inner corona, solar physicists reported December 12 at the fall meeting of the American Geophysical Union. That previously unseen structure could help solve some of the sun’s biggest puzzles, including how the solar wind is born and why the corona is so much hotter than the solar surface.
The corona is made up of charged plasma, which roils in famous loops and fans that follow magnetic field lines emerging from the surface of the sun (SN Online: 8/17/17). At a certain distance from the sun, though, that plasma escapes the corona and streams through the solar system as the solar wind, a constant flow of charged particles that pummels the planets, including Earth (SN Online: 8/18/17).

But solar physicists don’t know where the plasma gets enough energy to accelerate away from the massive, magnetic sun. And they don’t understand why the corona, which sizzles at several million degrees Celsius, has such higher temperatures than the solar surface, which chills at a mere 5,500° C (SN Online: 8/20/17).

Both problems might be cleared up by better understanding an energetic process called reconnection, which happens when magnetic field lines merge when they get too close to each other. Reconnection releases energy and helps move plasma around, so the process could be important to heating the corona and driving solar wind.

But in the best observations until now, the outer corona appeared smooth and uniform. To explain that smoothness, field lines would have to keep their distance from each other without a lot of reconnection. What’s more, physicists couldn’t tell where the boundary between the corona and the solar wind began, which might help to find that missing energy source.
“That’s changed,” solar physicist Craig DeForest of the Southwest Research Institute in Boulder, Colo., said at the AGU meeting. “Using STEREO, we’ve recently been able to drill in deeply enough to see the transition at the outer edge of the corona, where the dynamics change from what we might call coronal plasma to what we might call the young solar wind plasma.”

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DeForest and colleagues collected data for three days with STEREO in 2014 to gain more detail about small-scale changes in the outer corona than previously obtained. The researchers also processed the resulting images in a new way to bring those changes into focus.

Surprisingly, the team found that the outer corona is full of moving blobs and fine streams of plasma that vary in density by a factor of 10, suggesting that the magnetic field lines there are moving and merging more than scientists thought. “It turns out the apparent smoothness is a reflection of our instruments, not the corona itself,” DeForest says. “There’s almost certainly reconnection in the outer corona.”

The researchers also found that the corona probably fades into the solar wind between 14 million and 56 million kilometers away from the sun — about 10 to 40 times the sun’s diameter. That’s still a big range, but NASA’s Parker Solar Probe spacecraft, scheduled to launch in 2018, will fly right through that boundary. The probe will swoop within 6.4 million kilometers of the sun and take the first direct measurements of the corona — and perhaps figure out more precisely where the corona becomes the solar wind.

For now, the STEREO observations “are just tantalizing hints at an entire new set of phenomena,” DeForest says. Understanding the details of those processes “is going to require both careful analysis from Parker Solar Probe and also new, better imaging instruments.”

Solar physicist Steven Cranmer of the University of Colorado Boulder, who has made simulations of magnetic reconnection in the outer corona, finds the results exciting. Questions about the sun’s hot corona and the acceleration of the solar wind are still unsolved “not because of a lack of ideas, but because there are too many ideas,” he says. “I think we’re getting close to having the data that will let us rule out a good swath of these proposed ideas.”

The science behind kids’ belief in Santa

Over the past week, my little girls have seen Santa in real life at least three times (though only one encounter was close enough to whisper “yo-yo” in his ear). You’d think that this Santa saturation might make them doubt that each one was the real deal. For one thing, they looked quite different. Brewery Santa’s beard was a joke, while Christmas-tree-lighting Santa’s beard was legit. Add to that variations in outfits and jolliness levels.

But as I delved into the Santa-related research, I found I was wrong to think his omnipresence might throw my kids off. It turns out that the more kids see real, live Santa Clauses, the more likely they are to think he’s real. More exposure actually tracked with stronger belief, scientists reported in Cognitive Development in 2016.

That got me wondering about this belief. Like many parents, I feel a little hint of unease when it comes to telling my trusting, innocent children a lie. But lots of parents conspire to tell this lie to their children. An AP survey from 2011 (the most recent I could find on this pressing issue) revealed that 84 percent of adult respondents believed in Santa as a child.

Many of these former children had their Christmas beliefs shattered around age 8, other studies suggest. A fascinating paper from 1978 found that 85 percent of 4-year-olds believed in Santa. Five percent didn’t, and 10 percent were still thinking about it. But only 25 percent of 8-year-olds believed in Santa, with 20 percent not believing and 55 percent transitioning in their beliefs. Funnily enough, 60 percent of these same 8-year-olds still believed in the tooth fairy.
This shift in belief from age 4 to 8 has some psychology behind it. The influential child psychologist Jean Piaget proposed that around age 8 children enter the “concrete operational stage” of thinking — a critical, observant phase of questioning impossible things. (To be clear, it is impossible for Santa to fly around the world and deliver toys to all the houses, even with the 48 hours he’d have thanks to the Earth’s time zones, and other time-warping assists. Physicists have looked into it.)

Eight-year-olds’ discerning mindset was detected in a study that prodded children to list not toys, but questions for Santa. Young children tended to ask clarifying sorts of questions, such as “Is the North Pole cold?” “What are your elves’ names?” and “What do your reindeer do during the summer?” Those questions get at minor details without coming close to the central mysteries at the heart of a magical Santa. Older kids, however, were more likely to ask the toughies: “How do you fit inside a chimney?” and “How can you see everyone in the whole wide world?”

Once these questions start coming from your kid, the end may be in sight. But take heart, from yet another scientific study of Santa. Children are a sturdy bunch, and do pretty well after they find out the truth, interviews showed. In fact, it’s probably a relief when the entire world stops gaslighting kids and they finally get their hunches confirmed. The bad news is that the parents didn’t fare so well, describing themselves as predominantly sad after their children learned the truth.

For parents, their children’s discovery is an end of an era, a loss of a ritual tied up in family, tradition and treats. But sadder to me, I think, is that when that reckoning comes to my little girls, it will be a vivid reminder that my time with my small children is scant. These moments of magical thinking fly by faster than Santa would need to travel to complete his furious dash around the world.

Ask AI: How not to kill online conversations

A new artificial intelligence could tell whether your next post to an online forum will engage others or fall flat.

Computer scientist Qiaozhu Mei of the University of Michigan in Ann Arbor and colleagues trained a machine-learning program on about 63,000 Reddit threads to learn what dialog-ending responses look like.

This kind of chat-savvy computer code, described in a paper accepted to the 2018 Web Conference in Lyon, France, could someday notify users before they hit “submit” if a post is likely to shut down discussion. Such feedback could lead to more satisfying and productive online conversations.
AI’s guide to being an online conversationalist
Stay on topic. Posts that repeat words used elsewhere in a thread or use more related terms are less likely to end a conversation.

Share experiences. Comments that include words such as “talked,” “heard” or “seen” are liable to incite further discussion.

Keep it moving. The more time that elapses between a post and a reply, the more likely that reply will go unanswered.

Elaborate. Unlike in-person chats, where long monologs can bore those within earshot, lengthier online posts tend to get more responses.

Be polite. Posts that include words like “Mr.” and “Mrs.” are more likely to encourage a back and forth, compared with responses that address people with insulting or intense language, such as curse words or an all-caps “YOU.”

Tiny scales in ancient lagoon may be the first fossil evidence of the moth-butterfly line

Newly described little scaly bits could push back the fossil record of the moth-and-butterfly branch on the tree of life by some 70 million years. That raises the question of whether the drinking-straw mouthparts evolved long before the flower nectar many drink today.

The microscopic ridged scales date from roughly 200 million years ago, around the time of one of Earth’s less famous mass extinctions, says fossil-pollen specialist Bas van de Schootbrugge of Utrecht University in the Netherlands. During an unrelated study of ocean oxygen during this dire time, he and his colleagues pulled up cores of sediment in northern Germany near Braunschweig from what had once been a huge lagoon. In the sediment lay mere dots of insect scales.
Comparing the ridges and inner structure of the scales with those from modern insects suggests the fossils came from the evolutionary branch of insects that today gives us moths and butterflies with nectar-sipping mouthparts. No recognizable mouthparts appeared in the sediment. Yet the early existence of distinctive scales might mean this moth-butterfly drinking organ, a proboscis, evolved before the explosion of the classic flowering plants that offer nectar for pollination, van de Schootbrugge and colleagues propose January 10 in Science Advances.
The land already had plants: ferns, mosses and their relatives growing under trees that formed just-about naked seeds, without cushy protective ovaries and other floral coddling. Naked-seeded plants, many of them wind-pollinated such as pines and other conifers, thrive today. But the great evolutionary burst of true flowers—magnolias, roses, legumes, asters and the whole multicolored rainbow — that many moths and butterflies pollinate had yet to arise.These fossils date from a turbulent time when the great land mass called Pangea was cracking into continents. As the Triassic Period ended and the Jurassic dawned, volcanic eruptions on the straining land spewed greenhouse gases and toxins that changed the atmosphere and climate.
The previous record-holder for earliest moth-butterfly fossils came from about 130 million years ago, a bit after a major expansion of flowering plants. But when coauthor Timo van Eldijk, also at Utrecht, compared the newly found insect scales with those from silverfish, beetles and other scaly insects, modern scales of a big branch of the moth-butterfly lineage proved the best match.
In the times of the ancient scales, generally hot and dry conditions might have favored mouthparts specialized for drinking whatever liquids were to be found, the researchers propose.

Other work on how this proboscis evolved proposes that early moths started with chewing mouthparts and ate spores and pollen, says Harald W. Krenn of the University of Vienna. He and colleagues have proposed an intermediate phase of a short, tubelike structure good for slurping up droplets such as “honeydew” copiously excreted by sap-feeding aphids. A big question, though, is when early moths might have evolved such a drinking convenience.

The notion that the moth mouthparts arose before a big floral takeover sounds plausible to paleoecologist Conrad Labandeira of the Smithsonian Institution in Washington, D.C. Drinking-straw mouthparts had evolved in at least three other big insect groups (dipteran flies, lacewings and scorpionflies) somewhat before the full floral evolutionary extravaganza. Even some of the ancient naked-seeded plant groups, such as cycads, secrete nutritious droplets from reproductive structures that modern insects visit.

Interpreting the scales as a sign of an early moth proboscis is “possible,” says taxonomist Erik van Nieukerken of the Naturalis Biodiversity Center in Leiden, the Netherlands, whose specialties include early moths. There are other possibilities, too, for imagining ancient moth mouthparts, he cautions. Saying definitely that the newfound scales reveal the dawn of the proboscis might be “a bit too quick.”

DNA solves the mystery of how these mummies were related

A pair of ancient Egyptian mummies, known for more than a century as the Two Brothers, were actually half brothers, a new study of their DNA finds.

These two, high-ranking men shared a mother, but had different fathers, say archaeogeneticist Konstantina Drosou of the University of Manchester in England and her colleagues. That muted family tie came to light thanks to the successful retrieval of two types of DNA from the mummies’ teeth, the scientists report in the February Journal of Archaeological Science: Reports. The finding highlights the importance ancient Egyptians placed on maternal lines of descent, Drosou’s group contends.
Questions have swirled about the biological backgrounds of the mummified men ever since they were found together in a tomb near the village of Rifeh in 1907. The tomb dates to ancient Egypt’s 12th Dynasty, between 1985 B.C. and 1773 B.C. Coffin inscriptions mention a female, Khnum-Aa, as the mother of both men. And both mummies are described as sons of an unnamed local governor. It has always been unclear if those inscriptions refer to the same man, but discoverers decided the mummies were full brothers, because the two were buried next to each other and had the same mother.

Over time, differences discovered in the men’s skull shapes and other skeletal features raised suspicions that the Two Brothers were not biologically related at all. And some researchers argued that the inscriptions indicating the men had the same mother were misleading.

Adding to those doubts, a 2014 paper reported differences between the two mummies’ mitochondrial DNA, suggesting one or both had no biological link to Khnum-Aa. Mitochondrial DNA typically gets inherited from the mother.

But that study extracted ancient DNA from liver and intestinal samples using a method susceptible to contamination with modern human and bacterial DNA, Drosou’s team argues. In the new work, researchers isolated and assembled short pieces of mitochondrial and Y-chromosome DNA from both mummies’ teeth using the latest methods. The Y chromosome determines male sex and gets passed from father to son. This approach minimizes potential contamination from modern sources (SN Online: 5/31/17).
That new DNA evidence “proves the hieroglyphic text [on the mummies’ coffins] to be accurate,” at least in saying the mummified men had the same mother, says Egyptologist and study coauthor Campbell Price, curator of the Egypt and Sudan collections at the Manchester Museum in England.

Unlike the deference given to Khnum-Aa as a named parent of both interred individuals, he says, the coffin inscriptions must refer to different fathers who were considered peripheral family members and thus left unnamed. “Power may have been transferred down the female line rather than simply by a son inheriting [high rank] from his father,” Price suggests. Khnum-Aa’s background, social standing and genetic makeup, however, remain a mystery.

Genetic evidence that two half brothers were buried in the same tomb and placed in coffins that name only their mother makes sense, says Egyptologist Joann Fletcher at the University of York in England. Many written sources from ancient Egypt show precedence to the maternal line, “from the official lists of Egypt’s early kings whose names are accompanied by those of their mothers to nonroyal individuals, who likewise cite only their mother’s name,” Fletcher explains.

Dates of death on the mummies’ linen wrappings suggest that Khnum-Nakht died first, at around age 40, Price says. A few months later, Nakht-Ankh died at about age 60. The causes of their deaths are unknown.

Speed of universe’s expansion remains elusive

Unless you are a recent arrival from another universe, you’ve no doubt heard that this one is expanding. It’s getting bigger all the time. What’s more, its growth rate is accelerating. Every day, the universe expands a little bit faster than it did the day before.

Those day-to-day differences are negligible, though, for astronomers trying to measure the universe’s expansion rate. They want to know how fast it is expanding “today,” meaning the current epoch of cosmic history. That rate is important for understanding how the universe works, knowing what its ultimate fate will be and even what it is made of. After all, the prime mission of the Hubble Space Telescope when it was launched in 1990 was to help determine that expansion rate (known, not coincidentally, as the Hubble constant, named for the astronomer Edwin Hubble).
Since then evidence from Hubble (the telescope) and other research projects has established a reasonably precise answer for the Hubble constant: 73, in the units commonly used for this purpose. (It means that two independent astronomical bodies separated by 3.26 million light-years will appear to be moving away from each other at 73 kilometers per second.) Sure, there’s a margin of error, but not much. The latest analysis from one team, led by Nobel laureate Adam Riess, puts the Hubble constant in the range of 72–75, as reported in a paper posted online January 3. Considering that as late as the 1980s astronomers argued about whether the Hubble constant was closer to 40 or 90, that’s quite an improvement in precision.

But there’s a snag in this success. Current knowledge of the universe suggests a way to predict what the Hubble constant ought to be. And that prediction gives a probable range of only 66–68. The two methods don’t match.

“This is very surprising, I think, and very interesting,” Riess, of the Space Telescope Science Institute in Baltimore, said in a talk January 9 at a meeting of the American Astronomical Society.

It’s surprising because astrophysicists and cosmologists thought they had pretty much figured the universe out. It’s made up of a little bit of ordinary matter, a lot of some exotic “dark matter” of unknown identity, and even more of a mysterious energy permeating the vacuum of space, exerting gravitational repulsion. Remember that acceleration of the expansion rate? It implies the existence of such energy. Because nobody knows what it is, people call it “dark energy,” while suspecting that its real name is lambda, the Greek letter that stands for “cosmological constant.” (It’s called a constant because any part of space should possess the same amount of vacuum energy.) Dark energy contributes something like 70 percent of the total mass-energy content of the universe, various lines of evidence indicate.
If all that’s right, then it’s not all that hard to infer how fast the universe should be expanding today. You just take the recipe of matter, dark matter and dark energy and add some ghostly subatomic particles known as neutrinos. Then you carefully measure the temperature of deep space, where the only heat is the faint glow remaining from the Big Bang. That glow, the cosmic microwave background radiation, varies slightly in temperature from point to point. From the size of those variations, you can calculate how far the radiation from the Big Bang has been traveling to reach our telescopes. Combine that with the universe’s mass-energy recipe, and you can calculate how fast the universe is expanding. (You can, in fact, do this calculation at home with the proper mathematical utensils.)

An international team’s project using cosmic microwave background data inferred a Hubble constant of 67, substantially less than the 73 or 74 based on actually measuring the expansion (by analyzing how the light from distant supernova explosions has dimmed over time).

When this discrepancy first showed up a few years ago, many experts believed it was just a mirage that would fade with more precise measurement. But it hasn’t.

“This starts to get pretty serious,” Riess said at the astronomy meeting. “In both cases these are very mature measurements. This is not the first time around for either of these projects.”

One commonly proposed explanation contends that the supernova studies are measuring the local value of the Hubble constant. Perhaps we live in a bubble, with much less matter than average, skewing expansion measurements. In that case, the cosmic microwave background data might provide a better picture of the “global” expansion rate for the whole universe. But supernovas observed by the Hubble telescope extend far enough out to refute that possibility, Riess said.

“Even if you thought we lived in a void…, you still are basically stuck with the same problem.”

Consequently it seems most likely that something is wrong with the matter-energy recipe for the universe (technically, the cosmological standard model) used in making the expansion rate prediction. Maybe the vacuum energy driving cosmic acceleration is not a cosmological constant after all, but some other sort of field filling space. Such a field could vary in strength over time and throw off the calculations based on a constant vacuum energy. But Riess pointed out that the evidence is growing stronger and stronger that the vacuum energy is just the cosmological constant. “I would say there we have less and less wiggle room.”

Another possibility, appealing to many theorists, is the existence of a new particle, perhaps a fourth neutrino or some other relativistic (moving very rapidly) particle zipping around in the early universe.

“Relativistic particles — theorists have no trouble inventing new ones, ones that don’t violate anything else,” Riess said. “Many of them are quite giddy about the prospect of some evidence for that. So that would not be a long reach.”

Other assumptions built into the current cosmological standard model might also need to be revised. Dark matter, for example, is presumed to be very aloof from other forms of matter and energy. But if it interacted with radiation in the early universe, it could have an effect similar to that of relativistic particles, changing how the energy in the early universe is divided up among its components. Such a change in energy balance would alter how much the universe expands at early times, corrupting the calibrations needed to infer the current expansion rate.

It’s not the first time that determining the Hubble constant has provoked controversy. Edwin Hubble himself initially (in the 1930s) vastly overestimated the expansion rate. Using his rate, calculations indicated that the universe was much younger than the Earth, an obvious contradiction. Even by the 1990s, some Hubble constant estimates suggested an age for the universe of under 10 billion years, whereas many stars appeared to be several billion years older than that.

Hubble’s original error could be traced to lack of astronomical knowledge. His early overestimates turned out to be signals of a previously unknown distinction between different generations of stars, some younger and some older, Riess pointed out. That threw off distance estimates to some stars that Hubble used to estimate the expansion rate. Similarly, in the 1990s the expansion rate implied too young a universe because dark energy was not then known to exist and therefore was not taken into account when calculating the universe’s age.

So the current discrepancy, Riess suggested, might also be a signal of some astronomical unknown, whether a new particle, new interactions of matter and radiation, or a phenomenon even more surprising — something that would really astound a visitor from another universe.

Lakers vs. Warriors final score, results: Golden State forces Game 6 as Anthony Davis suffers head injury

Faced with a do-or-die situation in Game 5, the Warriors came up big.

A 121-106 win at Chase Center kept Golden State's season alive as they successfully avoided elimination at the hands of the Lakers. The series will now head back down to Los Angeles for Game 6, where LeBron James and Co. will have another chance to punch their ticket to the Western Conference Finals.

Stephen Curry led the way for the Warriors with 27 points and eight assists. Andrew Wiggins finished with 25 points and seven rebounds, while Draymond Green had one of his best games of the postseason with 20 points and 10 rebounds.

A bad night got even worse for LA when Anthony Davis was forced to leave the game late in the fourth quarter. He appeared to take a shot to the face from Golden State's Kevon Looney, and TNT's Chris Haynes reported that he was taken down the tunnel in a wheelchair. The Lakers now face an anxious wait to see whether he'll be good to go for a massive Game 6.

The Sporting News was tracking all the key moments as the Warriors defeated the Lakers in Game 5 of the Western Conference semifinals:

Lakers vs. Warriors score
Team Q1 Q2 Q3 Q4 Final
Lakers 28 31 23 24 106
Warriors 32 38 23 28 121
Lakers vs. Warriors live score, updates, highlights from Game 5
12:31 a.m. FINAL — The final buzzer rings out, and we're headed to a Game 6. Curry finishes with 27 points, Wiggins with 25 and Draymond Green with 20.

12:27 a.m. — Darvin Ham has raised the white flag and sent in his reserves. Golden State is going to get the win, and their season is going to continue. An excellent performance by the Warriors tonight with their backs against the wall.

12:24 a.m. — Both teams continue to trade blows, but with time ticking down, the Warriors look like they're going to cruise to a win here. Davis still hasn't returned to the court, and it sounds like he may be dealing with some dizziness and vision difficulties. He'll probably be sidelined for the rest of the game.

12:19 a.m. — Steph with a big shot! A triple from the corner extends the lead back to 14 points! It's Warriors 109, Lakers 95 as we enter the final minutes.

12:16 a.m. — Draymond gets the crowd on its feet with a nice jumper, but Austin Reaves answers at the other end with a three from way downtown! The Lakers have chipped away and the lead is now down to just nine points with 5:25 left.
12:14 a.m. — Davis is having to head down the tunnel and towards the locker room after that injury. TNT's Chris Haynes reported he looked a little shaky on his feet and needed some help to stay upright. Let's hope he's OK.

12:09 a.m. — Gary Payton II finishes with the hoop and harm over LeBron, and the crowd is loving it. To add insult to injury for the Lakers, Anthony Davis appeared to take an elbow to the face on the other end. He appears to be in significant discomfort, and he is forced to head to the bench.

12:03 a.m. — Any momentum the Lakers may have had has quickly vanished early in the fourth quarter. Curry drains a pull-up jumper with the shot clock winding down, then Wiggins converts on a running floater in the lane to stretch the lead back to 15 points. LA is running out of time here.
11:55 p.m. END OF THIRD QUARTER — The Lakers use a mini-run to cut into the lead slightly. LeBron converts on a layup with time winding down in the quarter, and we enter the final frame with Golden State up 93-82. James appeared to land on the foot of Wiggins on that last shot, and he was grimacing a little bit as he walked away. Something to keep an eye on.

11:49 p.m. — With the third quarter winding down, the Warriors are showing no signs of letting up. Curry just blew right by three defenders for an easy layup, and once again Darvin Ham has used a timeout to try and spark something from his team.

11:41 p.m. — How about Draymond Green in this game? He's been sensational so far, racking up 18 points on 6 of 10 shooting from the field. He just converted on another layup to make it 85-70, Warriors.

11:32 p.m. — The Lakers are off to a terrible start in this half, and in the blink of an eye the Warriors have stretched their lead to 18 points! Wiggins caps off a 9-2 Golden State flurry with a one-handed putback slam and Darvin Ham takes a timeout to stop the bleeding. That could be a huge momentum swing in this game.
11:27 p.m. START OF SECOND HALF — And away we go in the third quarter. Can the Warriors hold off the Lakers to stay alive?

11:20 p.m. — Davis leads all scorers with 18 points at the half while Wiggins leads Golden State with 16. James has 17 and Curry has 12, including that buzzer-beater to make it an eleven-point game.

11:11 p.m. END OF FIRST HALF — Stephen Curry lights up Chase Center with a three to beat the buzzer! That's just his second trey of the night, but it sends the Warriors into the locker room with a 70-59 lead! They ended the half on a 16-5 run to take control of Game 5.
11:03 p.m. — We knew a run was coming from one of these teams, and this time it has come from the Warriors! Poole connects from deep, then Wiggins follows it up with a triple of his own. After a Lakers timeout, the home team leads 64-56 with less than two minutes left in the half.

10:56 p.m. — LeBron isn't cooling off, and he drives for a layup then knocks down a three moments later to tie things up at 50 apiece. Back and forth we go.

10:51 p.m. — Andrew Wiggins gets a bucket and a foul, then does it again less than 40 seconds later! That pair of three-point plays puts the Warriors back in the lead by five with seven minutes remaining in the first half.

10:45 p.m. — Now LeBron is starting to get going! He buries a pair of three-pointers to take his tally to 12 points on the night and give the Lakers the lead. After he sinks a pair of free throws, it's 41-40, LA.
10:37 p.m. END OF FIRST QUARTER — Whew, time to catch your breath! A Jordan Poole floater with six seconds left on the clock has made it 32-28 Warriors at the end of the first quarter. They could really use a good performance from him tonight. If the game continues like this, we're in for a treat.

10:35 p.m. — This game has been fast-paced and a lot of fun so far. Davis continues to fill it up and he's up to 13 points as we near the end of the first quarter. But 20-year-old Moses Moody has knocked down a pair of threes to keep Golden State's lead intact. They're up 30-26 with just over a minute left in the period.

10:27 p.m. — But here come the Lakers! Anthony Davis is getting himself involved, and his putback dunk cuts the Warriors' lead to just five points. He has nine points already in the early going.

10:20 p.m. — This has been one heck of a start by the Warriors. Gary Payton II drains a three, Draymond converts on another layup and then Stephen Curry opens his account for the night with a three from way downtown. The home team is out to a 17-5 lead less than five minutes into the game.
10:17 p.m. — Draymond Green is off to a fast start! He buries a three to get the Warriors on the board, and his layup through contact draws a foul and leads to a three-point play. Golden State leads 9-3 early.

10:12 p.m. — And there's the opening tip. We are underway in San Francisco.

10:07 p.m. — Knicks-Heat just wrapped up. meaning Warriors-Lakers is up next on TNT. Can Golden State do what New York did and stave off elimination at home in Game 5?

9:59 p.m. — Steph was doing Steph things in pregame warmups.
9:52 p.m. — No surprises from the Lakers with their starting lineup.
9:46 p.m. — For the second game in a row, Gary Payton II gets the start for Golden State.
What channel is Lakers vs. Warriors on?
Date: Wednesday, May 10
TV channel: TNT
Live streaming: Sling TV
Lakers vs. Warriors will air on TNT. Viewers can also stream the game on Sling TV.

Fans in the U.S. can watch the NBA Playoffs on Sling TV, which is now offering HALF OFF your first month! Stream Sling Orange for $20 in your first month to catch all the games on TNT, ESPN & ABC. For games on NBA TV, subscribe to Sling Orange & Sports Extra for $27.50 in your first month. Local regional blackout restrictions apply.

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What time is Lakers vs. Warriors tonight?
Date: Wednesday, May 10
Time: 10 p.m. ET | 7 p.m. PT
Lakers vs. Warriors will tip off around 10 p.m. ET (7 p.m. local time) on Wednesday, May 10. The game will be played at the Chase Center in San Francisco.

Lakers vs. Warriors odds
Golden State is a 7.5-point favorite heading into Game 5.

 Warriors    Lakers

Spread -7.5 +7.5
Moneyline -350 +260
For the full market, check out BetMGM.

Lakers vs. Warriors schedule
Here is the complete schedule for the second-round series between Los Angeles and Golden State:

Date Game Time (ET) TV channel
May 2 Lakers 117, Warriors 112 10 p.m. TNT
May 4 Warriors 127, Lakers 100 9 p.m. ESPN
May 6 Lakers 127, Warriors 97 8:30 p.m. ABC
May 8 Lakers 104, Warriors 101 10 p.m. TNT
May 10 Game 5 10 p.m. TNT
May 12 Game 6* TBD ESPN
May 14 Game 7* TBD ABC

Mysterious high-energy particles could come from black hole jets

It’s three for the price of one. A trio of mysterious high-energy particles could all have the same source: active black holes embedded in galaxy clusters, researchers suggest January 22 in Nature Physics.

Scientists have been unable to figure out the origins of the three types of particles — gamma rays that give a background glow to the universe, cosmic neutrinos and ultrahigh energy cosmic rays. Each carries a huge amount of energy, from about a billion electron volts for a gamma ray to 100 billion billion electron volts for some cosmic rays.
Strangely, each particle type seems to contribute the same total amount of energy to the universe as the other two. That’s a clue that all three may be powered by the same engine, says physicist Kohta Murase of Penn State.

“We can explain the data of these three messengers with one single picture,” Murase says.

First, a black hole accelerates charged particles to extreme energies in a powerful jet (SN: 9/16/17, p. 16). These jets “are one of the most promising candidate sources of ultrahigh energy cosmic rays,” Murase says. The most energetic cosmic rays escape the jet and immediately plow through a sea of magnetized gas within the galaxy cluster.

Some rays escape the gas as well and zip towards Earth. But less energetic rays are trapped in the cluster for up to a billion years. There, they interact with the gas and create high-energy neutrinos that then escape the cluster.
Meanwhile, the cosmic rays that escaped travel through intergalactic space and interact with photons to produce the glow of gamma rays.

Murase and astrophysicist Ke Fang of the University of Maryland in College Park found that computer simulations of this scenario lined up with observations of how many cosmic rays, neutrinos and gamma rays reached Earth.

“It’s a nice piece of unification of many ideas,” says physicist Francis Halzen of the IceCube Neutrino Observatory in Antarctica, where the highest energy neutrinos have been observed.

There are other possible sources for the particles — for one, IceCube has already traced an especially high-energy neutrino to a single active black hole that may not be in a cluster (SN Online: 4/7/16). The observatory could eventually trace neutrinos back to galaxy clusters. “That’s the ultimate test,” Halzen says. “This could be tomorrow, could be God knows when.”