Shashank Bengali, reporting for Los Angeles Times: By his second day in the hospital with COVID-19, Charles Pignal's mild cough and 102-degree fever had disappeared. Bored and "bouncing off the walls" of his room in the isolation ward at Singapore's National Center for Infectious Diseases, he felt like he could go out and play a set of tennis. The 42-year-old footwear executive told his mother on the phone, "I'll be out of here in a couple of days." But Pignal would test positive for the coronavirus for five more weeks, despite developing no further symptoms. He wasn't released until the 40th day after he first fell ill, when he finally tested negative two days in a row. Cases like his are coming under increasing scrutiny as medical researchers worldwide puzzle over why the coronavirus -- which typically lasts about two to three weeks in the body -- appears to endure longer in some patients, even relatively young, healthy ones.

With studies showing that asymptomatic patients can transmit the SARS-CoV-2 virus, understanding how the virus leaves the body is among the most urgent mysteries facing researchers as governments in the United States and across the world begin to reopen their economies. Although studies show that the average recovery time from COVID-19 is two weeks, and nearly all patients are virus-free within a month, "less than 1% to 2%, for reasons that we do not know, continue to shed virus after that," said Hsu Li Yang, a physician specializing in infectious diseases at the Saw Swee Hock School of Public Health at the National University of Singapore. In recent weeks, China and South Korea have reported that some patients who had recovered from COVID-19 tested positive again in follow-up visits. In extreme cases, patients in the Chinese city of Wuhan, where the outbreak began late last year, reportedly tested positive 70 days after recovery. Doctors in both countries said they didn't believe the patients had been reinfected, a worrisome possibility because of its implications for building widespread immunity to a disease for which there is no vaccine. They also had no evidence that the patients had infected others.

Scientists created a monoclonal antibody that can defeat the new coronavirus in the lab, an early but promising step in efforts to find treatments and curb the pandemic's spread. From a report: The experimental antibody has neutralized the virus in cell cultures. While that's early in the drug development process -- before animal research and human trials -- the antibody may help prevent or treat Covid-19 and related diseases in the future, either alone or in a drug combination, according to a study [PDF] published Monday in the journal Nature Communications. More research is needed to see whether the findings are confirmed in a clinical setting and how precisely the antibody defeats the virus, Berend-Jan Bosch of Utrecht University in the Netherlands and colleagues wrote in the paper. The antibody known as 47D11 targets the spike protein that gives the new coronavirus a crown-like shape and lets it enter human cells. In the Utrecht experiments, it didn't just defeat the virus responsible for Covid-19 but also a cousin equipped with similar spike proteins, which causes Severe Acute Respiratory Syndrome, or SARS.

America's Environmental Protection Agency "granted permission for genetically engineered mosquitoes to be released into the Florida Keys and around Houston to see if they can help limit the spread of mosquito-borne illnesses," writes Bloomberg Environment.

clovis (Slashdot reader #4,684) shared their report on ab experimental use permit granted to British biotech company Oxitec Ltd: Oxitec's first field trial in Brazil achieved up to a 96% suppression of target disease transmitting mosquito populations in dense urban settings, the company said. But in public comments on the permit approval docket, Jaydee Hanson, policy director at the Washington, D.C.-based Center for Food Safety, questioned Oxitec's claims and warned of other possible dangers.

"Most (but not all) of the GE mosquitoes' offspring die at the late larval stage, in the water where the female mosquitoes lay their eggs," Hanson wrote."This partial survival rate, even if low (a reported 3 to 4% in laboratory conditions), would lead to the establishment of hybrid mosquitoes in the environment, which might possess altered properties, including the potential for enhanced disease transmission or resistance to insecticides," Hanson said.
The U.S. agency said it "looks forward to receiving field test results regarding the effectiveness of this promising new tool that could help combat the spread of mosquito-borne diseases like the Zika virus."

Global health officials and diplomats are "alarmed" by America's "apparent lack of interest in cooperation" on international efforts for a vaccine against Covid-19. Slashdot reader Charlotte Web quotes this report from Politico: The fear is that Trump will be content with allowing the race to develop and distribute the vaccine to devolve into a global contest -- and that poorer countries will be left behind in the rush to procure doses. In essence: that the president's "America First" view of world affairs as an atavistic scramble for power will lead to unnecessary suffering and death. "The worst situation would be, if when these tools are available, they go to the highest bidder -- that would be terrible for the world," said Melinda Gates, who, along with her tech entrepreneur husband, Bill, leads a powerful foundation that has devoted billions to health research. "Covid-19 anywhere is Covid-19 everywhere. And that's why it's got to take global cooperation."

The ongoing global scramble for masks, gloves and other personal protective gear offers a harrowing and potentially instructive example. Now imagine, officials and experts say, a similar competition to obtain vaccine doses: It could drag out the health crisis by letting the virus spread for longer than it otherwise might, devastating the very countries least equipped to fight it... It's not just the U.S. that has put the needs of its own citizens first. Dozens of countries, including the U.S. and some in Europe, have imposed travel restrictions as well as limits on the exports of masks and other critical medical equipment. Global health leaders are trying to avoid a repeat of such nationalist tactics when it comes to vaccines and other types of medicines that could combat Covid-19.
"Health officials and analysts caution that it's too early to go into full-fledged panic about a looming global vaccine fistfight," the article notes.

But it also points out that "There's no binding treaty or other mechanism that governs how a vaccine will be produced and distributed worldwide."

"A new, Linux-like platform could transform the way medicine is developed — and energize the race against COVID-19," reports Fast Company, while arguing that the old drug discovery system "was built to benefit shareholders, not patients."

Fast Company's technology editor harrymcc writes: Drug development in the U.S. has traditionally been cloistered and profit-motivated, which means that it has sometimes failed to tackle pressing needs. But an initiative called the Open Source Pharma Foundation hopes to apply some of the lessons of open-source software to the creation of new drugs — including ones that could help fight COVID-19.
From the article: The response to COVID-19 has been more open-source than any drug effort in modern memory. On January 11, less than two weeks after the virus was reported to the World Health Organization, Chinese researchers published a draft of the virus's genetic sequence. The information enabled scientists across the globe to begin developing tests, treatments, and vaccines. Pharmaceutical companies searched their archives for drugs that might be repurposed as treatments for COVID-19 and formed consortiums to combine resources and expedite the process. These efforts have yielded some 90 vaccine candidates, seven of which are in Phase I trials and three of which are advancing to Phase II. There are nearly 1,000 clinical trials listed with the Centers for Disease Control and Prevention related to COVID-19.

The gathering of resources and grassroots sharing of information aimed at combating the coronavirus has put open-source methods of drug development front and center. "It's our moment," said Bernard Munos, a former corporate strategist at pharma company Eli Lilly... Munos has been arguing for an open-source approach to developing drugs since 2006. "A lot is at stake because if it's successful, the open-source model can be replicated to address other challenges in biomedical research."
So now the Open Source Pharma Foundation hopes to offer "a platform where scientists and researchers can freely access technological tools for researching disease, share their discoveries, launch investigations into molecules or potential drugs, and find entities to turn that research into medicine..." according to the article.

"If the platform succeeds, it would allow drugs to succeed on their merit and need, rather than their ability to be profitable."

Syfy Wire's "Bad Astronomy" column is written by astronomer Phil Plait, head science writer of Bill Nye Saves the World. This week he looked at the recently-declassified videos taken by the U.S. Navy's fighter jets showing unidentified flying objects "moving in weird and unexpected ways." ("The 'aura' around the object in some of the footage could simply be the camera overexposing around a bright object; infrared cameras can do that, creating an odd glow.")

But to prove they're not aliens, Plait ultimately cites an analysis on the site MetaBunk, "run by former video game programmer and critical thinker Mick West" -- and his videos summarizing discussions on the site's bulletin board:

[I]n this one he argues, convincingly to me, that the FLIR video just shows a passenger plane seen from a distance. He also shows that the rotation of the object in the GIMBAL video is almost certainly due to the motion of the camera itself as it tracks the objects. The fighter jet is turning, and at the same time the camera is mounted on a rotating mechanism that allows it to track. These two motions combine to make a somewhat confusing series of rotations in the image, which is why the object in the video appears to rotate around.

But my favorite bit is a video where he gives a single, simple explanation that accounts for two things seen in the Navy videos, specifically, why the object in the GOFAST video appears to scream across the water so rapidly, and how in the GIMBAL video the object seems to travel against a strong wind. The answer: It's an illusion due to parallax, how an object close to you seems to move more rapidly against a more distant background as the camera moves... Given the distance, angle, and motion, it's likely that the GOFAST video shows a balloon.
As a kind of consolation prize, the column concludes by sharing the cheesy opening credits to a 1970 precursor to the TV show Space: 1999 -- called UFO.

Charlotte Web writes: The U.S.-based research non-profit Ecohealth Alliance has spent 20 years investigating the origins of infectious diseases like Covid-19 in over 25 countries, "to do scientific research critical to preventing pandemics."

America just cut it's funding.

Trump's reason? "Unfounded rumors" and "conspiracy theories...without evidence," according to reports in Politico and Business Insider. The group had received a total of $3.7 million through 2019 (starting in 2014), publishing over 20 scientific papers since 2015 on how coronaviruses spread through bats, including at least one paper involving a lab in China. But during a White House press briefing, a conservative web site incorrectly stated the whole $3.7 million had gone to that single lab, while even more erroneously implying that that lab was somehow the source of the coronavirus. They'd then asked "Why would the U.S. give a grant like that to China?" and President Trump vowed he would revoke the (U.S.-based) nonprofit research group's grant, which he did 10 days later.
Slashdot referenced that research nonprofit just this Sunday, citing a recent interview with the group's president who'd said they'd found nearly 3% of the population in China's rural farming regions near wild animals already had antibodies to coronaviruses similar to SARS. "We're finding 1 to 7 million people exposed to these viruses every year in Southeast Asia; that's the pathway. It's just so obvious to all of us working in the field."

Yet Thursday Politico reported the Trump administration "has been pressuring analysts, particularly at the CIA, to search for evidence that the virus came from a lab and that the World Health Organization helped China cover it up," citing a person briefed on those discussions. People briefed on the intelligence also told them there is currently no evidence to support that theory.

Michael Morell, the former acting director and deputy director of America's CIA, also pointed out Thursday that the lab in question was in fact partially funded by the United States. "So if it did escape, we're all in this together."

"The race for a vaccine to combat the new coronavirus is moving faster than researchers and drugmakers expected," reported Dow Jones News Services this week, "with Pfizer Inc. joining several other groups saying that they had accelerated the timetable for testing and that a vaccine could be ready for emergency use in the fall." Pfizer said Tuesday it will begin testing of its experimental vaccine in the U.S. as early as next week. On Monday, Oxford University researchers said their vaccine candidate could be available for emergency use as early as September if it passes muster in studies, while biotech Moderna Inc. said it was preparing to enter its vaccine into the second phase of human testing... If the vaccine shows signs of working safely in the study, Moderna said the third and final phase of testing could start in the fall. The company said it could seek FDA approval to sell the vaccine by year's end, if it succeeds in testing...

Merck & Co., a longtime maker of vaccines, said it is talking to potential partners about three different technologies to manufacture coronavirus vaccines... Johnson & Johnson said earlier this month it shaved months off the usual timelines for developing a vaccine, and expects to start human testing of a coronavirus candidate as soon as September, with possible availability on an emergency-use basis in early 2021.
SFGate also reports that GlaxoSmithKline and the French pharmaceutical company Sanofi "expect their vaccine will be ready for human testing in the second half of 2020."

And the Associated Press notes that America's Food and Drug Administration (FDA) "is tracking at least 86 active different approaches among pharmaceutical companies, academic researchers and scientists around the globe." Dr. Peter Marks, director of the agency's Center for Biologics Evaluation and Research, adds "We expect about two dozen more to enter clinical trials by this summer and early fall."

"Data from connected scale users suggests Americans, on average, are not gaining weight during lockdowns," writes long-time Slashdot reader pfhlick.

The Washington Post reports: Withings, the maker of popular Internet-connected scales and other body-measurement devices, studied what happened to the weight of some 450,000 of its American users between March 22 — when New York ordered people home — and April 18. Despite concerns about gaining a "quarantine 15," the average user gained 0.21 pounds during that month... Over the same March-April period in 2019, Withings said its American users gained slightly less weight — 0.19 pounds on average — though fewer people had the scales last year...

Dariush Mozaffarian, dean of the School of Nutrition Science and Policy at Tufts University — who wasn't involved with the Withings analysis — said he found the results a bit disappointing. "With the shutdown of the restaurants, I thought the numbers would have gotten better," he said. Home-cooked meals tend to be healthier than dining out.
Withings' numbers varied slightly for other countires. But citing a professor of medicine at Stanford, the article notes that average weight gains may be misleading, since some people "may be hitting their groove during stay-at-home orders by embracing cooking and taking up jogging. But others could be using food to cope with stress and gaining large amounts of weight." In fact, 37% of the scale owners gained more than a pound. (Which, if my math is correct, suggests that the other 63% had to lose at least .13 pounds.)

The article also notes that for buyers of Withings' scales, "contributing aggregate data is a condition included in its terms of service; its customers don't get the option to opt out if they want to use Withings products."

Appearing on CNN Thursday, Bill Gates called America's coronavirus testing data "bogus," in part because "the United States does not make sure you get results in 24 hours." Business Insider reports: Testing in the U.S. remains a long and complicated task, and it can take several days before people are told whether they have tested positive or negative for COVID-19. "If you get your test results within 24 hours so you can act on it, then let's count it," Gates said, adding that people were most infectious within the first three to four days after infection and might continue to interact with others and spread the virus until they have definitive results. "What's the point of the test?" he said. "That's your period of greatest infectiousness."

Gates added that residents of low-income neighborhoods had lesser access to testing facilities and were not prioritized, despite indications that the virus has taken a disproportionate toll on marginalized communities. "Our system fails to have the prioritization that would give us an accurate picture of what's going on," he said.
While America is now testing about 200,000 people a day, the article cites experts from Harvard University who believe 20 million tests a day are what's needed to fully "remobilize the economy."

New submitter penandpaper shares an excerpt from a NASA press release: NASA has selected three U.S. companies to design and develop human landing systems (HLS) for the agency's Artemis program, one of which will land the first woman and next man on the surface of the Moon by 2024. NASA is on track for sustainable human exploration of the Moon for the first time in history. The human landing system awards under the Next Space Technologies for Exploration Partnerships (NextSTEP-2) Appendix H Broad Agency Announcement (BAA) are firm-fixed price, milestone-based contracts. The total combined value for all awarded contracts is $967 million for the 10-month base period. The following companies were selected to design and build human landing systems:

- Blue Origin of Kent, Washington, is developing the Integrated Lander Vehicle (ILV) -- a three-stage lander to be launched on its own New Glenn Rocket System and ULA Vulcan launch system.
- Dynetics (a Leidos company) of Huntsville, Alabama, is developing the Dynetics Human Landing System (DHLS) -- a single structure providing the ascent and descent capabilities that will launch on the ULA Vulcan launch system.
- SpaceX of Hawthorne, California, is developing the Starship -- a fully integrated lander that will use the SpaceX Super Heavy rocket. "With these contract awards, America is moving forward with the final step needed to land astronauts on the Moon by 2024, including the incredible moment when we will see the first woman set foot on the lunar surface," said NASA Administrator Jim Bridenstine. "This is the first time since the Apollo era that NASA has direct funding for a human landing system, and now we have companies on contract to do the work for the Artemis program."

Further reading: SpaceX and NASA Break Down What Their Historic First Astronaut Mission Will Look Like

Pioneering Australian scientist Robert May, whose work in biology led to the development of chaos theory, has died at age 84. The Guardian reports: Known as one of Australia's most accomplished scientists, he served as the chief scientific adviser to the United Kingdom, was president of the Royal Society, and was made a lord in 2001. Born in Sydney on January 8, 1938, May's work was influential in biology, zoology, epidemiology, physics and public policy. More recently, he applied scientific principles to economics and modeled the cause of the 2008 global financial crisis. On Wednesday, his friends and colleagues paid tribute to a man who they said was a gifted polymath and a "true giant" among scientists.

Dr Benjamin Pope, an Australian astrophysicist and student at Oxford from 2013 to 2017, said May was a role model, and meeting him was a highlight of his university career. "I became aware of his achievements almost as soon as I learnt anything about physics in university," Pope told Guardian Australia. "My first contact with computer programming was at the University of Sydney, in first year physics, where the example is to recreate Robert May's experiment with the bifurcation diagram and the logistic map. "His bifurcation diagram is one of the iconic diagrams in physics," he said. "[And] he made what was between three or four independent discoveries that lead to chaos theory. You might have heard of the butterfly effect ... May's is probably the other foundational, computational model of chaos."

An anonymous reader quotes a report from IEEE Spectrum: The city of Carmel, Ind., has trucks for plowing snow, salting streets, and carrying landscaping equipment. But one cherry-red pickup can do something no other vehicle can: produce its own hydrogen. A 45-kilogram metal box sits in the bed of the work truck. When a driver starts the engine, the device automatically begins concocting the colorless, odorless gas, which feeds into the engine's intake manifold. This prevents the truck from guzzling gasoline until the hydrogen supply runs out. The pickup has no fuel cell module, a standard component in most hydrogen vehicles. No high-pressure storage tanks or refueling pumps are needed, either.

Instead, the "hydrogen-on-tap" device contains six stainless steel canisters. Each contains a 113-gram button of an aluminum and gallium alloy. A small amount of water drips onto the buttons, causing a chemical reaction that splits the oxygen and hydrogen contained in the water. The hydrogen releases, and the rest turns into aluminum oxide, a waste product that can be recycled to create more buttons. Back in the garage, the driver can replace spent canisters with news ones to replenish the hydrogen supply. AlGalCo -- short for Aluminum Gallium Company -- has spent 14 years refining the technology, which is based on a process developed by distinguished engineer Jerry Woodall. In 2013, AlGalCo partnered with the Carmel Street Department to build a prototype for one of the city's Ford F-250 trucks. In tests, the red pickup has seen a 15 percent improvement in gas mileage and a 20 percent drop in carbon dioxide emissions.

New Slashdot submitter Joe2020 shares a report from the BBC: Firefighters in Corsica, France, are aiming to teach canines how to sniff out coronavirus, as they can other conditions. It's hoped that detection dogs could be used to identify people with the virus at public places like airports. Their trial is one of several experiments being undertaken in countries including the UK and the USA. "Each individual dog can screen up to 250 people per hour," James Logan, head of the London School of Hygiene & Tropical Medicine, told The Washington Post. "We are simultaneously working on a model to scale it up so it can be deployed in other countries at ports of entry, including airports." The dogs are trained using urine and saliva samples collected from patients who tested positive and negative for the disease.

"We don't know that this will be the odor of the virus, per se, or the response to the virus, or a combination," Cynthia Otto, director of the Working Dog Center at Penn's School of Veterinary Medicine, told the publication. "The dogs don't care what the odor is ... What they learn is that there's something different about this sample than there is about that sample."

NASA and SpaceX's most defining moment of our current space era is coming up at the end of this month, with its Demo-2 mission on May 27. The mission will be the first ever launch for SpaceX with humans on board, and for NASA, it'll mark the first return to U.S.-based astronaut launches since the Shuttle program flew its last flight in 2011. On Friday, representatives from both SpaceX and NASA briefed the media on the mission and the specifics of what it will involve when astronauts Bob Behnken and Doug Hurley board the Crew Dragon for its debut crewed performance. From a report: The first thing to note about this mission is that it's still technically a test, as noted in the "demo" name. This is the capstone demonstration in a series of such missions that will fully human-rate the SpaceX Crew Dragon and Falcon 9 for operational use. As noted during today's press briefings, a big chunk of the actual human rating process occurs during this final mission -- in fact, the majority of the actual final human rating happens on this flight, despite the many years of preparation and live tests to date, including the Demo-1 mission which was essentially a full round-trip flight, just without any astronauts on board. Even though it's technically a demonstration, the stakes couldn't be higher -- SpaceX has a lot to prove here, and it bears the utmost responsibility in terms of keeping Behnken and Hurley safe for the duration of the mission. Which, it turns out, is actually going to be longer than originally planned: NASA says the mission will last anywhere between 30 days and 119 days, depending on a few different factors, the most significant of which being how quickly the agency ends up being able to launch the first operational Commercial Crew mission, Crew-1, which will carry four astronauts, including two from NASA and one from Japan's space agency.

New submitter jsicolo shares a report: Nvidia Chief Scientist Bill Dally has released an open-source ventilator hardware design he developed in order to address the shortage resulting from the global coronavirus pandemic. The mechanical ventilator design developed by Dally can be assembled quickly, using off-the-shelf parts with a total cost of around $400 -- making it an accessible and affordable alternative to traditional, dedicated ventilators, which can cost $20,000 or more. The design created by Dally strives for simplicity, and basically includes just two central components -- a solenoid valve and a microcontroller. The design is called the OP-Vent, and in this video you can see how bare-bones it is in terms of hardware compared to existing alternatives, including some of the other more complex emergency-use ventilator designs developed in response to COVID-19.

Bill Gates, whose foundation is focusing its efforts to fight the coronavirus, doesn't think life will return to normal until there's a viable vaccine that can stop its spread. The good news is that it may take less time than many have been predicting. From a report: "Dr. Anthony Fauci has said he thinks it'll take around eighteen months to develop a coronavirus vaccine," Gates wrote in a blog post published Thursday. "I agree with him, though it could be as little as 9 months or as long as two years." Even if it takes 18 months, that would still be the fastest that scientists have created a new vaccine, Gates said, adding that he's thinks eight to ten of the 115 current COVID-19 vaccine candidates look promising. "I'm particularly excited by two new approaches that some of the candidates are taking: RNA and DNA vaccines," he wrote. "It might be a bit hard to see right now, but there is a light at the end of the tunnel."

Just as suddenly as it first formed, a record-breaking ozone hole has healed. The largest ozone hole to ever open up over the Arctic is now closed, after first opening up earlier this spring. From a report: Scientists monitoring the "unprecedented" hole at the Copernicus Atmospheric Monitoring Service (CAMS) announced the closure last week. Despite coronavirus lockdowns leading to a significant reduction in air pollution, researchers said the pandemic likely was not the reason for the ozone hole closing. "Actually, COVID19 and the associated lockdowns probably had nothing to do with this," CAMS tweeted Sunday. "It's been driven by an unusually strong and long-lived polar vortex, and isn't related to air quality changes." Now that the intense polar vortex has ended, the ozone hole has closed. CAMS said Monday that it does not expect the same conditions to occur next year.

An anonymous reader quotes a report from The New York Post: The World Health Organization lauded Sweden as a "model" for battling the coronavirus as countries lift lockdowns -- after the nation controversially refused restrictions. Dr. Mike Ryan, the WHO's top emergencies expert, said Wednesday there are "lessons to be learned" from the Scandinavian nation, which has largely relied on citizens to self-regulate. "I think there's a perception out that Sweden has not put in control measures and just has allowed the disease to spread," Ryan told reporters. "Nothing can be further from the truth."

Ryan noted that instead of lockdowns, the country has "put in place a very strong public policy around social distancing, around caring and protecting people in long-term care facilities." "What it has done differently is it has very much relied on its relationship with its citizenry and the ability and willingness of its citizens to implement self-distancing and self-regulate," Ryan said. "In that sense, they have implemented public policy through that partnership with the population." He said the country also ramped up testing and had adequate capacity in hospitals to handle any outbreaks. "I think if we are to reach a new normal, Sweden represents a model if we wish to get back to a society in which we don't have lockdowns," Ryan said. Last month, more than 2,300 Swedish researchers penned a letter demanding the government enact stricter regulations. "Until we get a better idea of the situation, I think it is a good idea to close schools, restaurants and entertainment venues," said Olle Kampe, an immunology researcher at the Karolinska Institute, in March.

"[Sweden], which has a population of 10.3 million, has seen more than 20,300 cases and 2,462 deaths as of Thursday afternoon -- far higher than its Nordic neighbors, which implemented stricter containment measures," the report adds.

UPDATE (5/22/2020): 19 days later, Covid-19 deaths in Sweden "were the highest in Europe per capita in a rolling seven-day average," reports the Guardian, citing data from the scientific online publication Ourworldindata.com. And Sweden's death rate per million (376) was "far in advance of Norway's (44), Denmark's (96) and Finland's (55) — countries with similar welfare systems and demographics, but which imposed strict lockdowns..."

"What are the implications if 'space-time' (as conceived of in the Einstein Theory of General Relativity) is quantized like all other aspects of matter and energy?" asks Slashdot reader sixoh1. Space.com reports of a new study that tried to find out: In order for the math of general relativity to work, this fabric of space-time has to be absolutely smooth at the tiniest of scales. No matter how far you zoom in, space-time will always be as wrinkle-free as a recently ironed shirt. No holes, no tears, no tangles. Just pure, clean smoothness. Without this smoothness, the mathematics of gravity simply break down. But general relativity isn't the only thing telling us about space-time. We also have quantum mechanics (and its successor, quantum field theory). In the quantum world, everything microscopic is ruled by random chance and probabilities. Particles can appear and disappear at a moment's notice (and usually even less time than that). Fields can wiggle and vibrate with a will all their own. And nothing can ever be known for certain. [...]

That's exactly what a team of astronomers did, submitting their results for publication in the Monthly Notices of the Royal Astronomical Society, and also posting their work to the online preprint site arXiv. And in a perfect coincidence, they searched for the frothiness of space-time using ... espresso. No, not the drink. ESPRESSO, the Echelle Spectrograph for Rocky Exoplanet and Stable Spectroscopic Observations, an instrument based at the European Southern Observatory's Very Large Telescope. As its name suggests, ESPRESSO was not designed to search for space-time frothiness, but it turned out to be the best tool for the job. And the astronomers pointed it at a perfect source: a run-of-the-mill gas cloud sitting over 18 billion light-years away. What makes this particular gas cloud especially useful is two facts. One, there is a bright source sitting just behind it, illuminating it. And two, there's iron in the cloud, which absorbs the background light at a very specific wavelength.

So from our vantage point on Earth, if space-time is perfectly smooth, that gap in the background light caused by the gas cloud should be just as narrow as if the cloud was sitting right next to us. But if space-time is frothy, then the light traveling over the billions of light-years will spread out, changing the width of the gap. The astronomers didn't find any hint of frothiness, which doesn't mean that it doesn't exist -- it just means that if space-time is frothy, we need more than 18 billion light-years to see it with our current technology. But the results were able to rule out some models of quantum gravity, sending them into the proverbial dustbin of physics history.