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Are supermassive black holes going to eat the universe?

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The largest black holes grow faster than their galaxies, according to new research.

Two studies from separate groups of researchers find that so-called supermassive black holes are bigger than astronomers would have calculated from their surroundings alone. Supermassive black holes are enormous gravity wells found in the center of large galaxies.

No stress, though: The black holes are generally no longer growing, and they aren’t capable of eating their host galaxies for dinner. [Science Fact or Fiction? The Plausibility of 10 Sci-Fi Concepts]

“The black hole is tiny compared to the whole galaxy, so we are very safe!” said Guang Yang, a graduate student at The Pennsylvania State University who led one of the new studies.

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Yang’s study found that the larger the galaxy, the faster the black hole grew in comparison to the birth rate of the galaxy’s stars. The other study found that the masses of supermassive black holes are about 10 times greater than would be expected if these central black holes grew at the same rate as the galaxies they inhabit.

Galaxies and their black holes

Astronomers are interested in the relationships between black holes and their galaxies for two main reasons. First, if they can calculate the size of one based on another, they can determine, say, the mass of a supermassive black hole even if they can’t directly measure it. Second, any constant relationships between the two can help explain the laws that govern how galaxies are formed.

In the first study, published this month in the journal Monthly Notices of the Royal Astronomical Society and available on the preprint site ArXiv, Yang and his colleagues used data on more than 30,000 galaxies from the Great Observatories Origins Deep Survey (GOODS). The astronomical survey combined observations from the Hubble Space Telescope, the Chandra X-ray Observatory and the Spitzer Space Telescope, and more than 500,000 galaxies from the Cosmic Evolution Survey (COSMOS), which uses both space- and ground-based telescopes to explore the universe. The galaxies were between 4.3 billion and 12.2 billion light-years from Earth.

The research team found that the larger the galaxy, the larger the ratio between its black hole’s growth rate and its growth rate of stars. A galaxy containing 100 billion of Earth’s sun’s worth of stars (a measurement known as solar mass) has 10 times the ratio as a galaxy with 10 billion of the sun’s worth of stars. [The Strangest Black Holes in the Universe]

“Our paper suggests big galaxies can feed their black holes more effectively than small galaxies,” Yang told Live Science. “So, those big galaxies finally end up with very big black holes. However, it is still an unsolved mystery whether the black holes can affect galaxy formation in return.”

Going ultra

A second study, also available on ArXiv and set to be published in April in the journal Monthly Notices of the Royal Astronomical Society, similarly found that the larger the galaxy, the weirder its relationship with its black hole.

That research, headed by astrophysicist Mar Mezcua at the Institute of Space Sciences in Barcelona, Spain, focused on 72 galaxies no more than about 3.5 billion light-years from Earth. The galaxies were all “brightest cluster galaxies,” a term that refers to the biggest and brightest galaxies in the nearby universe. Using X-ray and radio-wave data from the Chandra X-ray Observatory, the Australia Telescope Compact Array, the Karl G. Jansky Very Large Array and the Very Long Baseline Array, the researchers compared the masses of supermassive black holes to estimates made using traditional methods that assumed that black holes and their galaxies grow more or less at the same rate.

Instead of finding the two growing in lockstep, the research team discovered that the black holes in their study were 10 times larger than would have been predicted with traditional means. In fact, many qualified not just as supermassive black holes, which clock in at a few billion solar masses, but as ultramassive black holes, which can be up to 40 billion times the mass of Earth’s sun.

No one previously knew that brightest cluster galaxies could host such enormous black holes, the researchers reported. The black holes could have formed in two ways, they wrote. One possibility is that the black hole grew first and the galaxy grew later. Another possibility is that these black holes are the descendants of “seed” black holes that formed when the galaxies were much younger and more productive in star formation. The bottom line, though, is that black holes and their galaxies don’t always grow as a matching set.  

Editor’s Note: This article was updated to correct a statement saying ultramassive black holes can be up to 40 “million” times the mass of the sun; they are up to 40 billion times the mass of our sun.

Original article on Live Science.

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Tokyo Olympics: Opening ceremony was ‘respectful, hopeful but sombre night’ | World News

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Olympic opening ceremonies are something of a unique art form. Playing to a global audience but with the host nation wanting to make the night their own.

Japan chose sombre. It was a respectful, hopeful but above all sombre night. They didn’t want to show off when everyone has lived through such hardship – and while so many people continue to do so.

Their display using 1,824 flying drones combining like a swarm of giant worker bees to create a giant globe stood out.

Naomi Osaka of Japan holds the Olympic torch after lighting the Olympic cauldron
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Naomi Osaka of Japan holds the Olympic torch after lighting the cauldron

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There were no Team GB fans at the 2021 summer olympic opening ceremony in Tokyo due to COVID-19 but Japan put on a stunning visual show regardless

So too Japanese tennis superstar Naomi Osaka who was given the honour of firing up the hydrogen-fuelled Olympic cauldron.

But it was their courteous bow towards the pain of the pandemic that defined the evening.

Video montages of empty cities during lockdowns, and athletes cobbling together training regimes in their back gardens – it all made for an understated opening ceremony.

Outside, the protests in the streets continued among those still vehemently against the Games taking place while Tokyo remains in a state of COVID emergency.

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There were also people outside who just felt drawn to the Olympic stadium – to come and wave to the very select numbers of VIPs and media going inside. It was as close as they could get to the Games that they had waited almost a decade for.

While these Olympics will feel unusual there were reminders too of the magic they can create.

There was a towering Tongan taekwondo player who strode into the stadium with his bare oiled chest puffed out as he carried his island nation’s flag like a warrior on a mission.

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Protests held outside Olympic stadium

The Olympics can still produce special moments like that and there will be plenty more over the coming weeks.

There will be more COVID-19 disruption too but the Games of 2020 are finally open, just one year late.

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Business leaders have ‘obligation to speak up’, ex-Unilever boss says amid Ben & Jerry’s row | Business News

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Unilever’s ex-boss has said business leaders have an “obligation to speak up” after his former company became embroiled in a row with Israel over its Ben & Jerry’s business.

Paul Polman mounted a defence of the need to “fight for what is right” in remarks to Sky News after the ice cream brand said it would stop selling its products in the occupied Palestinian territories.

Ben & Jerry’s is owned by consumer goods giant Unilever – whose array of brands ranges from Marmite spread to Dove soap – but has an independent board to take such decisions.

Alan Jope, Unilever chief executive
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Current boss Alan Jope has spoken to Israel’s prime minister about the matter

Its announcement is one of the strongest steps taken by a well-known company over Israel’s settlements, which are widely seen as illegal by the international community.

The move drew condemnation from the Israeli government, whose new prime minister Naftali Bennett said this week that Israel would “use the tools at its disposal – including legal – on this issue” and that those taking such action “need to know that there will be a price to pay”.

Mr Polman, speaking to Sky’s Ian King Live, said it would be inappropriate to say how he would have handled the issue had he still been in charge of Unilever.

But he added: “What is very important is if we want humanity to function for the long term we need to be sure that we fight for the basic values, the basic values of dignity, respect, equity, compassion.

“If we see these values being violated anywhere in the world I think we have an obligation to speak up.

“What we’ve seen in the US in the last few years – too few people, also from the business side, spoke up against things that then bit by bit moved the boundaries and put us in a very difficult situation.

Naftali Bennett will serve as prime minister for two years
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Israeli prime minister Naftali Bennett said there would be a “price to pay”

“So, fight for what is right and one of the few things we should fight for always is, these basic human rights.”

Mr Polman was speaking a day after current Unilever boss Alan Jope, in a conference call to discuss latest results, said the company remains “fully committed” to doing business in Israel but gave no indication that Unilever would press Ben & Jerry’s to reverse the decision.

Mr Jope, who has spoken to Mr Bennett on the phone to discuss the matter, said that it was a “complex and sensitive matter”.

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Tokyo Olympics 2020: Algerian judoka Fethi Nourine withdraws to avoid facing Israeli competitor Tohar Butbul | World News

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An Algerian judo competitor has withdrawn from the Tokyo Olympics after learning he could have faced an Israeli opponent.

Fethi Nourine said his political support for the Palestinian cause made it impossible to compete against Tohar Butbul.

He told Algerian TV he would not “get his hands dirty” and his “decision was final”.

“We worked a lot to reach the Olympics, and the news came as a shock, a thunder”, he added.

Tohar Butbul of Israel
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Tohar Butbul of Israel

The 30-year-old was drawn against Sudan’s Mohamed Asdalrasool on Monday for his first match in the men’s 73kg class. If he had won that match, he would have faced Butbul, who has a first-round bye, in the next round.

Nourine also withdrew from the world championships in 2019 for the same reason.

At the time, his coach Amar Ben Yaklif was quoted in Algerian media saying: “We were unlucky with the draw. We got an Israeli opponent and that’s why we had to retire. We made the right decision.”

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Tensions between Israel and Palestinians flared in Jerusalem earlier this year causing the worst violence in the region since 2014.

Tokyo 2020 Olympics - Judo - Training Sessions - Nippon Budokan, Tokyo, Japan - July 22, 2021. Technicians work on the mat in Nippon Budokan Arena, during training sessions. REUTERS/Sergio Perez
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Judo training sessions take place at the Tokyo Games

The conflict between the two sides has been going on for decades and has seen athletes from Iran and Egypt also previously refuse to compete against Israeli opponents.

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The opening ceremony for this year’s Olympic games took place on Friday, with fans not allowed in the national stadium for the event due to COVID-19 concerns.

Instead, around 1,000 dignitaries and members of the media were allowed the witness the spectacular event.

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