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Time appeared to move 5 times more slowly in 1st billion years after Big Bang, quasar ‘clocks’ reveal

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Time has been observed passing more slowly in quasars in the early universe.

The observed time dilation comes as a consequence of Albert Einstein’s theory of general relativity combined with the expansion of space. “At its heart, this is another ‘Einstein is right again’ story,” Geraint Lewis, a cosmologist at the University of Sydney, told Space.com.

Lewis and Brendon Brewer of the University of Auckland are co-authors on a new paper describing the long-sought after confirmation of time dilation effects in the variability of quasars. A quasar is powered by an accreting supermassive black hole at the heart of an extremely active galaxy. Because the accretion disk around the black hole is relatively small, fluctuations in the light emitted by the quasar can take place in just days. This makes them easier to track.

However, in the time since the light, and its fluctuations, was emitted from the 12 billion-year-old quasars, the universe has expanded greatly. This means that we are seeing the quasars as they existed over 12 billion years ago.

“We expected quasars to also exhibit this behavior, but previous searches had failed to find it,” said Lewis.

 

A new sample of 190 high-redshift quasars observed over 20 years by the Sloan Digital Sky Survey (SDSS), Pan-STARRS and the Dark Energy Survey, has provided Lewis and Brewer with the tools to finally detect time dilation in the variability of quasar light. The long period of observations coupled with telescopic sensitivity to the quasar fluctuations reveals the time dilation effect. Based on how slowly the fluctuations seem to be occurring, time in these quasars appears to run five times slower than it does for us in our frame of reference on Earth.

“We can pin-down the characteristics of their variability and show that quasars truly play ball with the cosmos,” said Lewis.

To be clear, time didn’t really run slow in those quasars relative to everything around them — in their frame of reference, time ran normally. Einstein’s theory of relativity and how he described the passage of time is based on the concept of frames of reference, and that these frames can be distinguished by their velocity relative to each other.

“The motion of distant galaxies is due to expanding space,” said Lewis. Consider that the Hubble constant describes how fast a volume of space 3.26 million light-years across is expanding per second. This is an incremental effect, where the expanding volumes of space add up. The farther a galaxy is from us, the more space has expanded between the galaxy and us, and the faster that galaxy seems to be moving away from us.

“Some of these quasars were moving faster than the speed of light, relative to us, when the photons were emitted,” said Lewis.

As Einstein showed, strange things happen when you approach the speed of light. One of these strange things is time dilation. A stationary observer on Earth would observe a clock traveling faster than them, whether on a spacecraft or in a quasar, appear to slow down. The faster the clock is moving, the greater the effect. At velocities approaching the speed of light, the effect is dramatically pronounced, resulting in peculiarities such as the twin paradox.

Time dilation is not just theoretical. It has been observed, albeit in tiny amounts, in satellites orbiting the Earth — the Global Positioning System has to take this into account. Cosmologically, time dilation has been observed in supernovae that exploded 6 to 7 billion years ago, but never in objects more distant than that until now.

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Besides being another successful test of Einstein’s theory of relativity, the time dilation observed in the quasars is also further evidence that we do indeed live in a universe that is expanding as a result of the Big Bang. If the universe were not expanding, the quasars would not appear to be moving at relativistic speeds relative to us. Lewis described the findings as “putting to bed some of the more extreme ideas that had been proposed, including that cosmologists have it all wrong, due to the previous failure to see quasar time dilation.”

 

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The body of a Ugandan Olympic athlete who was set on fire by her partner is received by family

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NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.

Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.

She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.

Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.

“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.

It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.

Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.

Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.

Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.

“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.

He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.

Kenya’s high rates of violence against women have prompted marches by ordinary citizens in towns and cities this year.

Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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B.C. sets up a panel on bear deaths, will review conservation officer training

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VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.

Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”

Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.

“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.

B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.

Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.

Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.

Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.

“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”

Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”

“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.

Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.

“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.

This report by The Canadian Press was first published Sept. 9, 2024.

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