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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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COVID-19: Rich ‘riding out pandemic in luxury’ as frontline workers struggle, says Oxfam | Business News

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The divide between rich and poor is “proving as deadly” as coronavirus, the boss of Oxfam said, as research shows the world’s richest people recouped their pandemic losses within just nine months.

The charity said it would take more than a decade for the world’s poorest to recover from the economic impacts of the pandemic.

A survey of 295 economists from 79 countries, commissioned by Oxfam, reveals that 87% of respondents expect an “increase” or a “major increase” in income inequality in their country as a result of the pandemic.

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Oxfam’s Inequality Virus report, released on the opening day of the World Economic Forum’s Davos Agenda, said it showed how current economic systems have allowed the wealthiest “to amass wealth in the middle of the worst recession since the Great Depression while billions of people are struggling to make ends meet”.

The charity also said its research demonstrated the manner in which the pandemic was deepening long-standing economic, racial and gender divides.

Oxfam’s executive director Gabriela Bucher said: “Rigged economies are funnelling wealth to a rich elite who are riding out the pandemic in luxury, while those on the frontline of the pandemic – shop assistants, healthcare workers, and market vendors – are struggling to pay the bills and put food on the table.

“Women and marginalised racial and ethnic groups are bearing the brunt of this crisis. They are more likely to be pushed into poverty, more likely to go hungry, and more likely to be excluded from healthcare.”

The six-day virtual Davos summit will feature Indian and Chinese leaders Narendra Modi and Xi Jinping.

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Ugandan court orders military and police to leave Bobi Wine’s property | World News

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A Ugandan court has ordered the military and police to stop surrounding the home of opposition leader Bobi Wine, who says he has been held under house arrest since the country’s presidential elections.

Mr Wine’s lawyer George Musisi told the Reuters news agency: “The judge ordered that the state and its agencies
should immediately vacate his property and his right to personal liberty should immediately be reinstated.”

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Boris Johnson calls for action against ‘devastating’ climate change with new coalition | Politics News

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Boris Johnson will call for countries to do more to tackle the “devastating” effects of climate change, as he launches a new partnership with five other countries and the United Nations.

The prime minister is due to announce the creation of the Adaptation Action Coalition formed with Egypt, Bangladesh, Malawi, the Netherlands and Saint Lucia.

It will work to turn international political commitments made through the UN into on-the-ground support for vulnerable communities.

Boris Johnson visits flood-affected areas in Greater Manchester.
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The PM will say he wants ‘real change’ and global leaders to act quickly

And the body will act as a forum for developed and developing countries to share suggestions on solutions to deal with climate change.

Mr Johnson is expected to say later today it is “undeniable” that climate change is “upon us” and “devastating lives and economies”, urging global political leaders to act quickly.

“I’ll be making the need for a resilient recovery a priority of the UK’s G7 presidency this year,” he will add.

“To make sure we get not just warm words but real change, I am today launching an all-new Adaptation Action Coalition to set the agenda ahead of COP26.”

COP26 is the annual climate change forum attended by world leaders being held in Glasgow later this year, after it was postponed last year due to the coronavirus pandemic.

Alok Sharma, the former business secretary who is now in charge of organising COP26 from within government, said he wanted “all countries to come forward with ambitious adaptation plans”.

And he said: “This important new coalition will crucially focus minds around the world to accelerate adaptation delivery in the areas most in need.”

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Despite the warm words, the government has come under some criticism recently for giving the go-ahead to a new coal mine opening in Cumbria.

Two teenagers and climate activists were on hunger strike for more than a week over the issue.

In his virtual party conference leader’s speech last October, Mr Johnson talked up the future of wind power – and took a dig at himself for once writing it “wouldn’t pull the skin off a rice pudding”.

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