Quantum particles can feel the influence of gravitational fields they never touch

If you’re superstitious, a black cat in your path is bad luck, even if you keep your distance. Likewise, in quantum physics, particles can feel the influence of magnetic fields that they never come into direct contact with. Now scientists have shown that this eerie quantum effect holds not just for magnetic fields, but for gravity too — and it’s no superstition.

Usually, to feel the influence of a magnetic field, a particle would have to pass through it. But in 1959, physicists Yakir Aharonov and David Bohm predicted that, in a specific scenario, the conventional wisdom would fail. A magnetic field contained within a cylindrical region can affect particles — electrons, in their example — that never enter the cylinder. In this scenario, the electrons don’t have well-defined locations, but are in “superpositions,” quantum states described by the odds of a particle materializing in two different places. Each fractured particle simultaneously takes two different paths around the magnetic cylinder. Despite never touching the electrons, and hence exerting no force on them, the magnetic field shifts the pattern of where particles are found at the end of this journey, as various experiments have confirmed (SN: 3/1/86).

In the new experiment, the same uncanny physics is at play for gravitational fields, physicists report in the Jan. 14 Science. “Every time I look at this experiment, I’m like, ‘It’s amazing that nature is that way,’” says physicist Mark Kasevich of Stanford University.

Kasevich and colleagues launched rubidium atoms inside a 10-meter-tall vacuum chamber, hit them with lasers to put them in quantum superpositions tracing two different paths, and watched how the atoms fell. Notably, the particles weren’t in a gravitational field–free zone. Instead, the experiment was designed so that the researchers could filter out the effects of gravitational forces, laying bare the eerie Aharonov-Bohm influence.
The study not only reveals a famed physics effect in a new context, but also showcases the potential to study subtle effects in gravitational systems. For example, researchers aim to use this type of technique to better measure Newton’s gravitational constant, G, which reveals the strength of gravity, and is currently known less precisely than other fundamental constants of nature (SN: 8/29/18).

A phenomenon called interference is key to this experiment. In quantum physics, atoms and other particles behave like waves that can add and subtract, just as two swells merging in the ocean make a larger wave. At the end of the atoms’ flight, the scientists recombined the atoms’ two paths so their waves would interfere, then measured where the atoms arrived. The arrival locations are highly sensitive to tweaks that alter where the peaks and troughs of the waves land, known as phase shifts.

At the top of the vacuum chamber, the researchers placed a hunk of tungsten with a mass of 1.25 kilograms. To isolate the Aharonov-Bohm effect, the scientists performed the same experiment with and without this mass, and for two different sets of launched atoms, one which flew close to the mass, and the other lower. Each of those two sets of atoms were split into superpositions, with one path traveling closer to the mass than the other, separated by about 25 centimeters. Other sets of atoms, with superpositions split across smaller distances, rounded out the crew. Comparing how the various sets of atoms interfered, both with and without the tungsten mass, teased out a phase shift that was not due to the gravitational force. Instead, that tweak was from time dilation, a feature of Einstein’s theory of gravity, general relativity, which causes time to pass more slowly close to a massive object.

The two theories that underlie this experiment, general relativity and quantum mechanics, don’t work well together. Scientists don’t know how to combine them to describe reality. So, for physicists, says Guglielmo Tino of the University of Florence, who was not involved with the new study, “probing gravity with a quantum sensor, I think it’s really one of … the most important challenges at the moment.”

Organic molecules in an ancient Mars meteorite formed via geology, not alien life

When researchers in 1996 reported they had found organic molecules nestled in an ancient Martian meteorite discovered in Antarctica, it caused quite a buzz. Some insisted the compounds were big-if-true evidence of life having existed on Mars (SN: 3/8/01). Others, though, pointed to contamination by earthly life-forms or some nonbiological origins (SN: 1/10/18).

Now, a geochemical analysis of the meteorite provides the latest buzzkill to the idea that alien life inhabited the 4.09-billion-year-old fragment of the Red Planet. It suggests instead that the organic matter within probably formed from the chemical interplay of water and minerals mingling under Mars’ surface, researchers report in the Jan. 14 Science. Even so, the finding could aid in the search for life, the team says.

Organic molecules are often produced by living organisms, but they can also arise from nonbiological, abiotic processes. Though myriad hypotheses claim to explain what sparked life, many researchers consider abiotic organic molecules to be necessary starting material. Martian geologic processes could have been generating these compounds for billions of years, the new study suggests.

“These organic chemicals could have become the primordial soup that might have helped form life on [Mars],” says Andrew Steele, a biochemist from the Carnegie Institution for Science in Washington, D.C. Whether life ever existed there, however, remains unknown.
Steele and his colleagues initially sought to study how ancient Martian water may have morphed minerals in the meteorite, known as ALH84001. The team used microscopic and spectroscopic imaging methods to analyze tiny slivers from parts of the meteorite that appeared to have reacted with water.

In their samples, the researchers discovered by-products of two chemical reactions — serpentinization and carbonation — which occur when underground fluids interact with minerals and transform them. Amid these by-products, the researchers detected complex organic molecules. Based on the identification of these two processes, the team concluded the organics probably formed during the reactions, just as they do on Earth.

Analysis of the relative amounts of different types of hydrogen in the organic matter supported the notion that the organic compounds developed while on Mars; they didn’t emerge later on from Earth’s microbes or materials used in the team’s experiments.

Altogether the findings suggest that at least two geologic processes probably produced organic matter on the Red Planet, says Mukul Sharma, a geochemist at Dartmouth College who was not involved in the study.

The study is not the only to propose that organic material in Martian rocks could form without life. Researchers attributed the formation of complex organics in the 600-million-year-old Tissint meteorite, also from Mars, to chemical interactions of water and rock (SN: 10/11/12).

However, ALH84001 is one of the oldest Martian meteorites ever found. The new findings, when considered alongside other discoveries of Martian organic matter, suggest that abiotic processes may have been generating organic material across the Red Planet for much of its history, Sharma says. “Nature has had a huge amount of time on its hands to produce this stuff.”

Though the work doesn’t bring us any closer to proving or disproving the existence of life on Mars, identifying abiotic sources of organic compounds there is crucial for the search, Steele explains. Once you’ve figured out how Martian organic chemistry acts without meddlesome life, he says, “you can then look to see if it’s been tweaked.”

An early outburst portends a star’s imminent death

A star’s death usually comes without warning. But an early sign of one star’s imminent demise hints at what happens before some stellar explosions.

In a last hurrah before exploding, a star brightened, suggesting that it blasted some of its outer layers into space. It’s the first time scientists have spotted a pre-explosion outburst from a run-of-the-mill type of exploding star, or supernova, researchers report in the Jan. 1 Astrophysical Journal.

Scientists have previously seen harbingers of unusual types of supernovas. But “what’s nice about this one is it’s a much more normal, vanilla … supernova that’s showing this eruption before explosion,” says astronomer Mansi Kasliwal of Caltech, who was not involved with the research.

On September 16, 2020, scientists discovered the explosion of a star roughly 10 times as massive as the sun, located about 120 million light-years away. Thankfully, telescopes that regularly survey a swath of the sky, as part of an effort called the Young Supernova Experiment, had been observing the star well before it detonated. About 130 days before the explosion, the star brightened, the researchers found, the start of a pre-explosion eruption.
The final explosion was a commonplace type of stellar detonation called a type 2 supernova, which occurs when the core of an aging star collapses. Precursors to such explosions probably hadn’t been seen before because the early eruptions are faint. For this supernova, scientists had observations of the star sensitive enough to pick up the relatively weak eruption.

Previous post-explosion observations of such supernovas have hinted that the stars slough off layers before death. In 2021, astronomers reported signs of a supernova’s shock wave plowing into material that the star had expelled (SN: 11/2/21). A similar sign of cast-off stellar material was also found in the new study.

Scientists aren’t sure exactly what causes such early outbursts. They could be the result of events happening deep within a star, for example, as the star burns different types of fuel as it nears death. If more such events are found, scientists may eventually be able to predict which stars will go boom, and when.

Precursor outbursts are a sign that stars experience inner turmoil before exploding, says study coauthor Raffaella Margutti, an astrophysicist at the University of California, Berkeley. “The main message that we are getting from the universe is that these stars are really knowing that the end is coming.”

Part donkey, part wild ass, the kunga is the oldest known hybrid bred by humans

From mules to ligers, the list of human-made hybrid animals is long. And, it turns out, ancient.

Meet the kunga, the earliest known hybrid animal bred by people. The ancient equine from Syro-Mesopotamia existed around 4,500 years ago and was a cross between a donkey and a hemippe, a type of Asiatic wild ass, researchers report January 14 in Science Advances.

Horses didn’t appear in this region of Asia until 4,000 years ago, centuries after their domestication in Russia (SN: 10/20/21). But dozens of equine skeletons were excavated in the early 2000s from a royal burial complex dating back to 2600 B.C. at Umm el-Marra in northern Syria. The animals, whose physical features didn’t match any known equine species, appear to be “kungas” — horselike animals seen in artwork and referenced in clay tablets predating horses by centuries.

“They were highly valued, very expensive,” says paleogeneticist Eva-Maria Geigl of Institut Jacques Monod in Paris.
Geigl and her colleagues analyzed a kunga’s genome, or genetic instruction book, and compared it with those of horses, donkeys and Asiatic wild asses, including the hemippe (Equus hemionus hemippus), which has been extinct since 1929. The kunga’s mother was a donkey and its father a hemippe, making it the oldest evidence of humans creating hybrid animals. A mule from 1000 B.C. in Anatolia reported by the same research group in 2020 is the next oldest hybrid.

Geigl thinks kungas were created for warfare, as they could pull wagons. Coaxing donkeys into dangerous situations is hard, she says, and no Asiatic wild ass can be tamed. But a hybrid might have had the characteristics people sought.

Coauthor E. Andrew Bennett, a paleogeneticist now at the Chinese Academy of Sciences in Beijing, likens kungas to “bioengineered war machines.” But with the riddle of how kungas were made being solved a century after the last hemippe perished, “it’s impossible to make these animals again.”

50 years ago, NASA’s space shuttle program got the green light

President Nixon’s announcement last week of the decision to begin development of a space shuttle system may prove to be nearly as crucial to the future of the manned space program as the 1961 Kennedy challenge to land a man on the moon.

The shuttle program was NASA astronauts’ ticket to space for 30 years. Beginning in 1981, five reusable spacecraft carried out many important missions, including helping to build the International Space Station and carrying the Hubble Space Telescope into orbit. Despite initial hopes that the shuttles would usher in an era of low-cost spaceflight, the program was deemed too expensive to continue and ended in 2011. Recently, NASA has begun working with private companies to transport astronauts to low Earth orbit. In 2020, SpaceX flew six astronauts to the International Space Station (SN: 12/19/20 & 1/2/21, p. 36). Last April, NASA announced it had tapped SpaceX to ferry astronauts to the surface of the moon as part of the upcoming Artemis program.

Patents won by Chinese companies in US surge

Chinese companies' patents granted in the United States surged last year, even as total patent awards in the US trended downward, showcasing Chinese companies' increasing innovation capabilities, according to a renowned US patent service provider.

Data from IFI Claims showed that Chinese companies' patents earned in the US increased around 10 percent to 20,679 in 2021, up from 18,792 in 2020.

The progress came as total US patent grants declined about 7 percent from 2020 to 327,329 awards last year, the most precipitous drop in the past decade, said IFI Claims.

Several Chinese companies are now among the Top 50 in US patent rankings, including chip giant Taiwan Semiconductor Manufacturing Co at No 4, telecom giant Huawei Technologies Co at No 5, display maker BOE at No 11, and tech heavyweight Oppo at No 49. Oppo, for instance, was granted 719 patents in the US last year, marking a surge of 33 percent year-on-year.

When it comes to total global patents held, China possesses 29 percent of the global 250 patent families-collections of patent applications covering the same or similar technical content-compared to the US (24 percent) and Japan (19 percent), said IFI Claims.

A deeper analysis shows that the US and Japanese portfolios are stronger and more mature. Nevertheless, it is clear that China has stimulated a research and development culture that is serious about intellectual property, said Mike Baycroft, CEO of IFI Claims Patent Services in a statement.

The progress comes as Chinese companies increasingly strengthen their R&D push. Huawei, for instance, invested 141.9 billion yuan ($22.3 billion) in R&D in 2020, accounting for about 15.9 percent of its revenue.

Jason Ding, head of the intellectual property department at Huawei, said earlier that the company has become one of the world's largest patent holders through investment in innovation.

Oppo is also beefing up its R&D push. Chen Mingyong, CEO of Oppo, said earlier that the company aims to be a tech pioneer by increasing R&D spending.

"We've been working hard for many years to ramp up our products," Chen said.

So far, Oppo has filed for patents in more than 40 countries and regions around the world as it accelerates efforts to expand its global business. As of Dec 31, 2021, Oppo had filed 75,000 patent applications globally, and its global number of authorized patents exceeds 34,000, the company said.

Popovich craves more teaching time

Gregg Popovich had ample time for a nice New York dinner, as long as a gut-wrenching loss didn't ruin his appetite.

Coronavirus-caused changes to the NBA schedule moved up San Antonio's game in Brooklyn on Sunday from a night to a noon tip-off. That left all evening for wine and unwinding at a restaurant in one of his favorite cities before another game against the Knicks the next day.

He still loves New York, though virus rules and regulations limit how much he can enjoy it now.

"Not as much as usual, just like I'm sure New Yorkers aren't enjoying it as much as usual," Popovich said. "But it's been fun to be here. It always is."

Just like New York is no longer the same, neither are the Spurs.

The 121-119 loss to the Nets was the kind of defeat his team racks up these days. The Spurs often pulled out games like those when Tim Duncan, Manu Ginobili and Tony Parker were on the floor, but it's a different story when young players now stand in their place.

After five championships during a run of 22 straight postseason appearances, the Spurs could be staring at a third straight season out of the playoffs. They headed home with a 15-25 record after going 1-6 on their trip that ended with a 111-96 loss to the Knicks on Monday.

In his 26th season with the Spurs, it's not the winning that Popovich misses. It's the teaching and team-building time that's so hard to find during another season altered by the virus.

"I never got too excited about the winning and I never got too down about any losses," Popovich said. "You'd rather win than lose, but it was never really the priority in how you lived your life or conducted yourself. We enjoyed the teaching, the camaraderie as much as anything. The airplanes, the buses, being with a great group of guys.

"This group entails, or requires, more teaching, but with COVID we're having a hard time finding those moments to be able to do that. So I'd say frustrating is a word that applies. But being able to have a group that's hungry and you can teach is a different kind of enjoyment than watching Timmy (Duncan) help us win, because he never listened to me anyway. He just did what he wanted to do, so I didn't have to do a whole lot. I just came, I had a front-row seat."

Now, he's putting together lineups with guys he barely knows. The Spurs finished their trip with six players in health and safety protocols, including Keldon Johnson, who won a gold medal playing for Popovich in last year's Olympics.

Rookie Josh Primo, who just turned 19, finished the trip in the starting lineup but will be spending what Popovich said is needed time in the NBA G League once the sidelined players are back. Devontae Cacok, who Popovich previously knew little about beyond that he played for the G League affiliate, impressed with his tenacity.

But opposing teams don't focus on the players. They look over at Popovich and expect the same tough test the Spurs always were.

"I know they don't got big names and they haven't been at that level the last couple of years, but that's just the culture they have over there. That's what Pop created," Nets star Kevin Durant said.

The Spurs successfully forced the ball out of Durant's hands on the Nets' final possession Sunday, which thrilled Popovich. But they allowed Cam Thomas to catch Durant's pass moving into the lane for the winning shot, the kind of mistake rebuilding teams make.

"It's a game of mistakes," Popovich said. "That's why the scores aren't 8-6. And those kinds of mistakes you just hope happen less and less as time goes on. But the tough part of this season for everybody, especially young teams, is no practices, no shootarounds. So it's kind of tough to get that across."

He'll keep trying and is confident the tough losses are going to turn into wins. The road has been rough, but Popovich has no complaints.

Well, maybe just one. Playing the Nets and Knicks on the same trip is nice, just not when there are no days off in between.

"I would like it, but I would like them to be spaced so I could go to dinner another night. The back-to-back kind of hurts the dinner thing. I'm being honest," Popovich said.

"But it's one of the enjoyable things about the NBA. You get to travel, they fly you for free, they get you a room. I mean, what could be better? You go to all these cities. This year it's a little tougher, but in general it's been great."

'Flying Turk' ready to hit new heights

ISTANBUL-Ski jumper Fatih Arda Ipcioglu, 24, was born at the foot of Mount Palandoken in eastern Turkey.

The region in Erzurum province has since developed into an important winter sports center, and is now Ipcioglu's base as he chases his Olympic dreams.

Encouraged by his father, Ipcioglu started skiing at a very young age, and at 11 became a licensed club athlete in ski jumping.

Now known as the "Flying Turk", he will represent his country at next month's Beijing Winter Olympics, where landing a "perfect jump" is his "biggest dream".

"I am proud and happy to go to the 2022 Winter Olympics in China," Ipcioglu told Xinhua in an online interview from Austria, where he was competing in a World Cup event.

In ski jumping, the margin between failure and success is slim, Ipcioglu explained.

"You can easily make big mistakes with small details and miss the meters, or you can also perform a perfect jump by fixing these minor details," he said.

Ipcioglu has not failed to notice the strides made by China in the sport over the relatively short period of time that it has competed at elite level, and reckons the host could spring some surprises at Beijing 2022.

"They are on a beautiful road. I hope this will continue after the Olympics," he said.

"The ski jumping family is wide open to new countries and new athletes. The sport gets better as it grows and is shared."

Ipcioglu, meanwhile, has backed the comprehensive COVID-19 countermeasures that will be implemented at the Games.

"There are very strict precautions. I'm aware of these because we have been told about the rules beforehand, and we know what to do and what not to do," Ipcioglu said. "I appreciate them in that regard. It is a very tough method but a correct one."

Chinese authorities say they have imposed a series of steps to overcome the challenges posed by the Omicron variant of the virus to "deliver a streamlined, safe, and splendid Winter Olympic Games for the world".

Ipcioglu believes staging the Olympic Games on schedule in a safe environment is preferable to a postponement.

"Let me put it this way, the postponement of the Olympics would be destructive for the athletes because everyone works for the Games and completes their training accordingly," he stressed. "I hope that the competitions will take place in a healthy environment, and everyone will return home safely."

Beijing 2022 is set to be one of the most innovative Games in Olympic history, with organizers promising the use of environmentally friendly technology, green energy, cloud broadcasting, 5G, and augmented reality tech.

"That is, of course, a beautiful thing as the Olympics also provide a platform to showcase the host country's innovations and technology to the world," he said.

At the end of the interview, Ipcioglu had a simple message:"Beijing 2022, we are coming!", before adding:"Together for a shared future."

US double standard on Capitol and Hong Kong attacks

Thursday marked the first anniversary of the Jan 6, 2021, attack on US Capitol by previous president Donald Trump's supporters who refused to accept the presidential election results, which declared Democratic candidate Joe Biden the winner. The storming of the Capitol by hundreds of demonstrators sent shockwaves across the United States and the world.

For the past year, the Biden administration has been pursuing the case. In July, the Democrat-controlled House of Representatives set up a select committee to investigate the case, despite most of the House Republicans boycotting the committee. More than 700 people have been charged for crimes related to the Capitol attack.

President Biden and Vice-President Kamala Harris were expected to deliver speeches on Thursday to mark the first anniversary of the attack, while House Speaker Nancy Pelosi announced a slate of related events including a prayer, a moment of silence on the House floor, a session for lawmakers to share their accounts of the attack, and a prayer vigil on the steps of the Capitol for those killed in the attack.

However, it is unlikely that the case will reach its logical conclusion because Democrats, as alleged by some Republicans, are trying to use the sordid incident to their advantage in this year's midterm elections and the 2024 presidential election, especially given Trump's continuing popularity among Americans.

For instance, a recent Pew survey showed the Republicans consider Ronald Reagan and Trump as the best recent US presidents. What is more troubling is that even a year after the 2020 election, a Bright Line Watch survey found that a large majority of Republican voters still refuse to accept that Biden won the presidential election. Only 27 percent of the Republican respondents said Biden was the rightful winner.

The sad reality was echoed by respondents to an NPR/Ipsos poll released on Monday. According to the poll, about 64 percent of Americans said they believe US democracy is "in crisis and at risk of failing", with two-thirds of the Republican respondents saying that "voter fraud helped Biden win the 2020 election".

The sharp divide has prompted many to ask if the US is careening toward a second civil war. In fact, about 46 percent respondents to a Zogby Poll in Feb of 2021 said they feared that another civil war is likely.

Besides, Brookings Institution scholars William Gale and Darrell West warned in a September article that "we should not assume it could not happen and ignore the ominous signs that conflict is spiraling out of control. Even if we do not end up in open combat, there could be an uptick in domestic terrorism and armed violence that could destabilize the country". They cited key issues of high levels of inequality and polarization in US society, from racial equity and voting rights to abortion and vaccines, and from 434 million firearms in civilian possession to hundreds of private militia groups.

These are indeed serious issues. Yet the US administration's relentless pursuit of the Jan 6 case has been in sharp contrast to Pelosi's description of the riots in the Hong Kong Special Administrative Region more than two years ago, especially the storming of the Hong Kong Legislative Council building on July 1, 2019, as a "beautiful sight to behold".

In that attack, hundreds of violent protesters broke through the glass walls and metal doors of the LegCo building and ransacked the LegCo chamber. The violence that marked the attack on the Hong Kong LegCo would make the Jan 6 storming of Capitol look a "minor" incident.

After the LegCo attack, the SAR authorities charged only dozens of people compared with the over 700 charged in the US Capitol case. Yet when each charge or arrest was made in the Hong Kong case, US politicians and lawmakers, including Pelosi, voiced concern or condemned the legal moves.
It is right to condemn the attack on the US Capitol. But people who condone or cheer the storming of the Hong Kong LegCo building are nothing but hypocrites whom no one should take seriously.

Tourism clamp clouds hopes for Thai revival

Halt to quarantine-free entry prompts reassessment of economic outlook

Hopes for Thailand's economic recovery have been dealt a blow with the suspension of a quarantine-free program for international tourists, say figures in the all-important hospitality industry who are readjusting their outlook for 2022.

"We are kind of seeing a replay of 2021 where ... hotels are focusing on domestic travel once again," said Bill Barnett, managing director of consultancy C9 Hotelworks in Thailand.

He said that winter in the northern hemisphere was always a key driver for Thailand's tourism sector. Sun-starved people from the region, such as those from the United Kingdom, Germany, Canada and Russia, would flock to the country's beaches and other attractions.

The quarantine-free program, called Test and Go, was launched on Nov 1 as Thailand reopened to tourists from 63 countries. Due to a spike in COVID-19 infections, new registrations for the program were halted on Dec 21. On Jan 7, the program was suspended indefinitely.

Barnett said the timing of the suspension "was not exactly very good".

After the suspension, Thai Prime Minister Prayut Chan-o-cha on Wednesday ordered the launch of a new tourism campaign under the theme Amazing Thailand New Chapter. As with the paused program, it is aimed at reviving the hard-hit tourism sector-a mainstay of the country's economy.

The government also plans to introduce an entry fee of 300 baht ($9) for incoming tourists, starting from April, Xinhua News Agency reported, citing spokesman Thanakorn Wangboonkongchana.

Thailand reported 8,167 new cases on Thursday, bringing the national tally to 2,300,457, data from the Centre for COVID-19 Situation Administration, or CCSA, showed.

The Omicron variant of COVID-19 accounted for 70 percent of the cases reported for the week to Jan 8, according to the Bangkok Post.

The CCSA forecast that the number of daily new cases could jump to 20,000 by the end of January if no serious measures are taken.

Despite the suspension of the Test and Go program, international tourists can still enter Thailand through a so-called Sandbox program, which allows travelers access to some places in the country after spending at least seven days within a Sandbox destination. In addition to Phuket in the south, the government decided on Jan 7 to add the islands of Ko Samui, Ko Tao and Ko Phangan to the program from Jan 11.

Panicha Thananaken, country manager of online travel company Traveloka Thailand, said demand for domestic travel has mitigated the impact of the Test and Go program suspension.

Long-term optimism

"Over the longer term, we remain optimistic about international travel," said Panicha, noting that Southeast Asia is home to one of the world's fastest-growing markets driven by a large middle class of roughly 300 million people with a strong interest in traveling and a thirst for international aspirations.

Businesses in the Thai tourism industry have called on the government to reconsider the entry restrictions for foreign tourists.

William Heinecke, chairman of hospitality company Minor International in Thailand, said "a more pragmatic approach should be considered" as entry restrictions may cause more harm than good, particularly when domestic transmission of Omicron has already taken root.

The spike in cases fueled by Omicron has also affected Thailand's economic outlook.

Kirida Bhaopichitr, director of the Economic Intelligence Service at the Thailand Development Research Institute, said she had to lower the forecast for Thailand's GDP growth this year to 3-3.5 percent from 3.5-4 percent after the latest spike in infections.

Indonesia opened its booster campaign on Wednesday as the country records rising infections driven by the Omicron variant.

Elsewhere in the region, the Philippines reported 32,246 new cases on Wednesday, the second-highest single-day tally since the pandemic began in January 2020.

Officials blamed the spike on high mobility, poor compliance with safety health protocols during the holiday season, and the fast-spreading Omicron and Delta variants.

Agencies contributed to this story.