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Why We Still Don’t Know How Fast the Universe is Expanding

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The task ended up falling to one of Dunkley’s former graduate students,
Graeme Addison, now a cosmologist at Johns Hopkins University. Addison
began exploring yet another way to reckon the expansion of the universe,
this time by looking at vibrations from the Big Bang that left an enormous
pattern of ripples etched into the distribution of galaxies across the
universe. That pattern is visible in the latest large-scale surveys. The
size of the cosmic ripples, when combined with other information about the
Big Bang, yields a measurement of the Hubble constant.


“It’s a third opinion on what’s going on,” Addison says. That opinion
aligns with Planck’s value of 67, “which suggests pretty strongly that you
can’t blame this discrepancy all on the Planck data.”

What the Heck is Going On?

Compared with old-school brawlers like Sandage, today’s researchers are a
genial and cautious bunch. They begin, sensibly, by considering human
error: the possibility that somebody messed up in collecting or analyzing
the data. But that’s looking increasingly unlikely.


“If you’d asked me three years ago, I’d have said, ‘The distance ladder is
pretty complicated, and there’s astrophysics that needs to be understood.’
But my opinion on that has changed because of the work, mainly from Riess
and his collaborators,” Addison says. “They’ve revisited the steps of the
distance ladder, done statistical tests, and none of that analysis has
shifted the Hubble constant anything near the amount you need to reconcile
with Planck.”


What’s most troubling — and exciting — is that so many lines of evidence
converge on two inconsistent answers. The persistent gap is forcing
cosmologists to consider that both measurements might be correct. Perhaps
the universe has a split identity: Maybe the early universe studied by
Planck, and the late universe studied by the Hubble telescope, really were
inconsistent, due to some undiscovered aspect of how the universe works.


Riess ticks off a range of possibilities, any one of which would qualify as
a major discovery. Space itself could have a slight curvature. There could
be an unknown type of neutrino, a ghostly type of particle that rarely
interacts with matter. Dark matter and dark energy could have “funny funky”
properties.


Dunkley suspects that the problems with current scientific understanding
may go even deeper than the kinds of relatively minor adjustments that
Riess describes. “There’s no single extension of the standard model of
cosmology that can explain the Planck data and the local measurements and
this vast suite of other data,” she says. “We’ve also got big issues to
figure out, like why is the universe accelerating, and why did it begin
expanding in the first place? I would not be surprised if we’ve got a major
upheaval coming.”


The current debate may seem smaller than the one that came before, but it
could prove large enough to deliver a whole new universe.

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Ecology

Globe Climate: Canada’s resource reckoning is coming

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Good afternoon, and welcome to Globe Climate, a newsletter about climate change, environment and resources in Canada.

This afternoon, the Alberta government announced that it is restoring a coal mining policy it revoked last spring. At the time, the move provoked a widespread public backlash detailed by The Globe. The original decision, which opened up more than 1.4 million hectares to exploration, was made without public consultation. Premier Jason Kenney previously defended the changes.

Lots more on coal and Canada’s resources industry in this week’s newsletter edition.

Now, let’s catch you up on other news.

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Ecology

‘Incredibly destructive’: Canada’s Prairies to see devastating impact of climate change

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As the climate continues to warm at an alarming rate, experts warn if dramatic steps to mitigate global warming are not taken, the effects in Canada’s Prairie region will be devastating to the country’s agriculture sector.

According to Environment and Climate Change Canada, the country is warming, on average, about double the global rate.

Scientists with the National Oceanic and Atmospheric Administration in the U.S. recently found 2020 was earth’s second-hottest year on record, with the average land and ocean surface temperature across the globe at 0.98 of a degree C above the 20th-century average.

However, the agency found the northern hemisphere saw its hottest year on record, at 1.28 degrees C above the average.

“(In Canada) we are looking at about 6.4C degrees of warming this century, which isn’t much less than one degree per decade, which is just a terrifying rate of warming,” Darrin Qualman, the director of climate crisis policy and action at the National Farmer’s Union said.

Qualman said there is “massive change coming” to Canada’s Prairies, which will be “incredibly destructive.”

“It’s not going too far to say that if we made that happen, parts of the Prairies wouldn’t be farmable anymore,” he said.

According to the federal government, in 2018 Canada’s agriculture and agri-food system generated $143 billion, accounting for 7.4 per cent of the country’s GDP.

The sector employed 2.3 million people in 2018. The majority of the 64.2 million hectares of farmland in Canada is concentrated in the Prairies and in southern Ontario.

The effects of climate change are already being felt on the ground in the Prairies, Qualman said, adding that the NFU has already heard from farmers complaining of “challenging weather.”

“People are sharing pictures of flattened crops and buildings, et cetera, that have been damaged,” he said. “And we’re still at the beginning of this.”

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Ecology

Insect-based dog food aims to cut your pet’s carbon pawprint

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Meat has an enormous carbon footprint, with livestock liable for about 15 per cent of worldwide emissions, as we have beforehand mentioned on this e-newsletter. That is prompted specialists to suggest consuming much less meat for sustainability (and well being) causes.

However what about your pet? One research discovered that the methane and nitrous oxide emissions generated by canine and cat meals within the U.S. alone had been equal to about 64 million tonnes of CO2, or roughly the quantity produced by 13.6 million automobiles. And it might be getting worse, with a development towards feeding pets “human-grade” meat.

That is prompted some pet meals makers to look to lower-carbon protein sources — together with bugs.

Research present that producing insect-based meals requires far much less feed, land and water and generates far fewer greenhouse fuel emissions per kilogram than meats comparable to beef, pork or rooster.

That is one of many causes increasingly more pet meals containing insect protein are hitting the market. Purina, a model owned by multinational Nestlé, launched a line of canine and cat meals containing black soldier fly larvae in Switzerland in November.

In Canada, Montreal-based Wilder Harrier began promoting canine treats made with cricket protein in 2015 and pet food made with black soldier fly larvae in 2019. It plans to broaden to launch a line of insect-based cat treats later this yr and cat meals in 2022 due to “a ton of demand,” mentioned firm co-founder Philippe Poirier.

Wilder Harrier initially labored with animal nutritionists on insect-based merchandise to unravel a unique downside — specifically, the founders’ canines had allergy symptoms to frequent meats utilized in canine meals. Poirier mentioned now about half its prospects hunt down the product due to their pets’ allergy symptoms and about half for environmental causes.

Dr. Cailin Heinze, a U.S.-based veterinary nutritionist licensed by the American School of Veterinary Vitamin, has written concerning the environmental influence of pet meals. She mentioned we’re typically “not as involved as we probably ought to [be]” concerning the environmental footprint of pets.

Alternatively, she famous that the longer-term influence of newer diets, comparable to vegan meals and people containing bugs, hasn’t been nicely examined in comparison with conventional pet meals.

Maria Cattai de Godoy, an assistant professor of animal sciences on the College of Illinois who research novel proteins for pet meals (together with bugs, yeast and plant-based substances), mentioned such substances are rigorously examined to find out their security and diet earlier than being added to pet meals. 

“This can be a very extremely regulated trade,” she mentioned, however admitted it is also evolving.

Relating to bugs, she mentioned constructive information “reveals promise in direction of utilizing them increasingly more in pet meals.” Insect-based proteins have additionally earned the endorsement of the British Veterinary Affiliation, which says some insect-based meals could also be higher for pets than prime steak.

However Godoy famous that there isn’t any one-size-fits-all resolution, and pet homeowners ought to take into consideration the wants of their very own particular person pet and analysis whether or not a specific weight loss plan can be appropriate.

She mentioned that other than the kind of protein, issues like packaging and manufacturing strategies may also make a distinction. For instance, utilizing meat byproducts that may in any other case turn into waste would not drive elevated meat manufacturing the identical approach as utilizing human-grade meat.

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