Friday, March 14, 2025
Home Blog Page 1359

Merging atomic clocks with quantum computers could lead to ultraprecise measurements of laws of nature

0
Merging atomic clocks with quantum computers could lead to ultraprecise measurements of laws of nature


Merging atomic clocks with quantum computers
Universal quantum operations for tweezer clocks. Credit: Nature (2024). DOI: 10.1038/s41586-024-08005-8

Physicists like to measure things, and they like those measurements to be as precise as possible. That means working at unfathomably small scales, where distances are much smaller than even the diameters of subatomic particles. Researchers also want to measure time down to a precision of less than one second per tens of billions of years. The quest for these ultraprecise measurements in physics is part of a growing field called quantum metrology.

Now, as reported in the journal Nature, a Caltech team led by Professor of Physics Manuel Endres has developed a new device that could lead to some of the most precise time measurements ever achieved. The method merges state-of-the-art atomic clocks with quantum computers.

“Our goal is to get to the ultimate precision allowed by nature,” Endres says. “We have now demonstrated the building blocks to get there.” The lead authors of the study are former Caltech postdoctoral scholar Ran Finkelstein, now at Tel Aviv University, and Caltech graduate students Richard Bing-Shiun Tsai and Xiangkai Sun.

The device that allows these precise time measurements will help physicists better probe the laws of nature, such as Albert Einstein’s general theory of relativity, and study some of the hardest problems in physics, such as the nature of dark matter. Detailed measurements of this sort are also needed to detect gravitational waves, the quietist ripples in space-time. (LIGO, the Laser Interferometer Gravitational-wave Observatory, managed by Caltech and MIT, recently achieved its own milestone in quantum metrology.)

Endres’s group has previously developed “tweezer clocks,” which consist of arrays of neutral strontium atoms, in which each atom is individually controlled by lasers (the tweezers). By themselves, tweezer clocks are highly precise at marking the passage of time. In the new study, the researchers have demonstrated how to perform quantum computations in a tweezer clock in order to make the clocks even more precise.

“Atomic clocks use quantum mechanics to measure time, while quantum computers use quantum mechanics to perform calculations,” Endres says. “Here, we are working at the interface of both.”

The challenge lies in entangling the atoms in the tweezer clock array. Entanglement is a phenomenon that occurs at quantum scales, in which particles become linked together without being in direct contact. “You can reach more precision if the atoms are entangled,” Endres says, “but we need a very specific complex form of the entanglement.”

The new study demonstrates that this entanglement is possible and, in general, that quantum computers can be integrated with quantum sensors such as atomic clocks. In the future, the researchers hope to further reduce errors in the system to bring their clocks even closer to theoretical limits of precision.

More information:
Manuel Endres, Universal quantum operations and ancilla-based readout for tweezer clocks, Nature (2024). DOI: 10.1038/s41586-024-08005-8. www.nature.com/articles/s41586-024-08005-8

Citation:
Merging atomic clocks with quantum computers could lead to ultraprecise measurements of laws of nature (2024, October 9)
retrieved 9 October 2024
from https://phys.org/news/2024-10-merging-atomic-clocks-quantum-ultraprecise.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.





Source link

Environmental law reform needed to protect endangered marine species in Australia’s waters, say researchers

0
Environmental law reform needed to protect endangered marine species in Australia’s waters, say researchers


bluefin tuna
Credit: Unsplash/CC0 Public Domain

University of Queensland researchers are calling for reforms to Australia’s environmental laws, as threatened fish species continue to be legally exported.

Their work has identified four species that have been listed under Australia’s Environment Protection and Biodiversity Conservation (EPBC) Act and legally exported from Australia: the orange roughy, blue warehou, school shark and southern bluefin tuna. The research is published in npj Ocean Sustainability.

Despite being listed as threatened under Australia’s under-review EPBC Act, UQ Ph.D. candidate Rosa Mar Dominguez-Martinez said these fish continue to be exported.

“Since the inception of the Act, 107 kilotons, or 10% of all Australian seafood exports, have been of these four listed threatened species,” Ms. Dominguez-Martinez said.

“You might think that there are plenty more fish in the sea, but these species are in real danger.

“In fact, Australia’s Threatened Species Scientific Committee—the expert group responsible for providing listing advice and recovery strategies—found that all of these species were eligible for listing in higher threat categories: Critically Endangered for the blue warehou and southern bluefin tuna, or Endangered for the school shark and orange roughy.

The researchers reveal that this occurs due to a loophole within the legislation.

“Currently, the EPBC Act includes a category unique to Australia called ‘Conservation Dependent,’ which only applies to marine fish species, as terrestrial species cannot be listed under this category,” Ms. Dominguez-Martinez said.

“There are eight species listed as ‘Conservation Dependent’ and all are caught in commercial fisheries. All of these species are required to have a legally enforced management plan aimed at stopping their decline—however, with the exception of the southern bluefin tuna, their conservation status has not improved, and they remain overfished, or are unassessed in Australia.

“This classification effectively exempts these species from the stricter regulations that would apply if they were listed under standard threat categories, such as Vulnerable, Endangered, or Critically Endangered.

“While other native species listed as threatened under the EPBC Act require a special permit for export, Conservation Dependent species are exempt from this requirement.

“So—while the EPBC Act currently undergoes federal review—we’re calling for Australia’s new legislation to treat commercially harvested threatened species the same as other threatened species.”

Senior author Associate Professor Carissa Klein said the team also recommend two other significant changes, which would better protect Australia’s threatened marine species.

“Australia’s new environmental protection legislation must also mandate regular review of the conservation status of all threatened species,” Dr. Klein said.

“If more regular reviews were done, species like the southern bluefin tuna—which is not currently assessed as overfished—would be de-listed from the EPBC Act more swiftly.

“And species acknowledged as threatened under international listings, such as the IUCN Red List or through global conventions, should be assessed in Australia’s new threatened species legislation.

“These recommendations are essential to prevent further extinctions in Australian waters.”

More information:
Rosa Mar Dominguez-Martinez et al, Environmental law reform needed to manage trade of Australia’s threatened marine species, npj Ocean Sustainability (2024). DOI: 10.1038/s44183-024-00085-3

Citation:
Environmental law reform needed to protect endangered marine species in Australia’s waters, say researchers (2024, October 9)
retrieved 9 October 2024
from https://phys.org/news/2024-10-environmental-law-reform-endangered-marine.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.





Source link

Canadian urban mobility is woefully lacking, but building a better future is still possible

0
Canadian urban mobility is woefully lacking, but building a better future is still possible


Canadian urban mobility is woefully lacking, but building a better future is still possible
Credit: University of Toronto Press

Canadian cities are falling behind globally when it comes to efficiently moving people. Long commute times, high congestion rates and infrastructure that is vulnerable to climate change are symptoms of a mobility crisis.

Mobility is an essential public good, and modern policies aim to move people in a safe, efficient, accessible and non-polluting way. However, the COVID-19 pandemic exposed and worsened existing vulnerabilities in Canada’s urban mobility systems, undermining progress toward these goals.

Our new book, Urban Mobility: How the iPhone, COVID, and Climate Changed Everything, explores how technology, the pandemic and climate change have shaped, and continue to shape, urban mobility, particularly for those with inadequate transportation networks.

Population growth outpacing transit

One of the primary challenges Canadian cities face is that they have grown faster than their sustainable transportation options. While urban populations have expanded, investment in public transportation has not kept pace, resulting in a gap between capacity and potential.

The COVID-19 pandemic also impacted city life in profound ways, and urban life and economies in Canada are still being affected to this day. Remote work became the norm for many, reducing the number of people commuting and causing a significant drop in public transit ridership.

Additionally, the shift to hybrid work has permanently altered how Canadians engage with their cities. People are shopping online more, using public transit less, and central business districts and physical retail spaces are seeing less foot traffic.

Urban economies, which have been designed to rely heavily on the movement and presence of large numbers of people through public transit and local businesses, are still grappling with this new reality. Activity levels, for instance, are down by about 20 percent from pre-pandemic levels in many downtown spaces still.

Tech platforms and mobility

Digital platform firms like Zoom, Uber, Amazon and Instacart adapted quickly during the pandemic, offering safe work-from-home options, private transportation and online shopping services to people. These platforms disrupted the traditional urban economic model, which relies on transit, physical stores and foot traffic.

Ride-hailing services drew passengers and their fares away from local economies into foreign-owned ride-hailing companies. Transit systems not only depend on the massive built public infrastructure, but also passenger fares and other government funding to maintain the public system over time.

In addition, these tech platform companies come with equity and accessibility concerns. Research on the use of ride-hailing and public transit during the pandemic found that its usage in Toronto was clearly organized along class, neighborhood and social lines. People identifying as one or more of the following were more likely to continue riding transit during the pandemic: low-income, immigrant, racialized, essential workers and car-less, in large part because other options were not available to them.

Similarly, in Calgary, private technology experiments in electric scooters privileged wealthier neighborhoods. Electric scooters were used more in wealthier neighborhoods, and as poverty levels increased at the neighborhood level, the use of them dropped. The researchers concluded that greater attention needs to be paid to ensuring all communities, regardless of economic status, have access to micro-mobility options.

Canada has a history of importing technological solutions, rather than creating its own. Montréal, however, offers a successful example with its Bixi bike program, the third largest bike share system in North America after New York and Chicago, with 11,000 bikes and almost 900 stations. A non-profit runs the program, Rio Tinto Alcan provides aluminum for the bikes and Cycles Devinci manufactures them in Saguenay-Lac-Saint-Jean.

Canadian cities need to build innovation opportunities that promote economic development and improve mobility at the same time. Canada’s technology sector is woefully undersupported at present.

Climate crisis intensifying challenges

The third, and perhaps most pressing challenge facing Canadian cities is the growing climate crisis. Cities are both instigators and victims of climate change. They contribute significantly to greenhouse gas emissions, but are also heavily impacted by severe weather events, heat waves and other side effects.

These impacts are becoming increasingly concerning with the intensification of wildfires, urban flooding and other extreme weather events.

By the end of the 20th century, most large Canadian cities were heavily investing in strategies to encourage people to use alternatives to cars, such as transit, light rail, biking and walking.

However, shifting priorities, ideologies and budgetary adjustments led to government cutbacks to transit funding and a lack of new transportation innovation. In Ontario, for example, the government continues to push unrealistic road-building ideas at the expense of more active transit options.

This failure to effectively move people around has left an opening for new mobility experiments led by private companies, but some of these programs don’t really integrate well into the Canadian urban mobility ecosystem. Many of these mobility options—such as ride-hailing—are also costly and exclusive. Others, like electronic scooters, can lead to e-waste.

Building a better future

The disruptions caused by technology, the pandemic and climate change are reshaping how people and goods move in cities. To build a better future, Canadian cities must address the interconnected challenges of three transitions: digital, health and environmental.

While all sectors need to invest, strong leadership and policy action from governments at all levels is needed to create a more climate-friendly, economically vibrant and equitable urban mobility future. Governments will need to embrace bold, innovative solutions that address all three of these challenges.

This means policy frameworks that reduce carbon emissions through climate action plans, leveraging political will and funding in efforts to shift away from private automobiles and toward transit, bike lanes and pedestrian pathways, and experimenting with digital mobility services while still prioritizing sustainability.

Provided by
The Conversation


This article is republished from The Conversation under a Creative Commons license. Read the original article.The Conversation

Citation:
Canadian urban mobility is woefully lacking, but building a better future is still possible (2024, October 9)
retrieved 9 October 2024
from https://techxplore.com/news/2024-10-canadian-urban-mobility-woefully-lacking.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.





Source link

Amazon says new technology in delivery vans will help sort packages on the fly and save time

0
Amazon says new technology in delivery vans will help sort packages on the fly and save time


Amazon says new technology in delivery vans will help sort packages on the fly and save time
The Amazon logo is seen, June 15, 2023, at the Vivatech show in Paris. Credit: AP Photo/Michel Euler, File

Amazon has revealed new technology that it says will help delivery drivers avoid organizing packages at stops or manually check to see if they have the right parcel for each delivery.

The technology—called Vision-Assisted Package Retrieval, or VAPR—is intended to cut down on the time and effort it takes drivers to retrieve packages, Amazon’s retail chief Doug Herrington said at a company event in Nashville on Wednesday.

Amazon expects to put 1,000 delivery vans that contain the technology on the road by early next year.

The company says VAPR essentially works like this: Once an Amazon delivery van arrives at a customer’s location, it will project a green “0” on packages that need to be dropped off, and a red “X” on those that should remain in the van.

The technology will also use audio and visual cues to let drivers know they have found the right package, Amazon said.

The Seattle company has been testing the new feature with its Delivery Service Partners, the businesses that deliver packages across the country for Amazon.

It said early tests have showed the technology helped reduce “perceived physical and mental effort” for drivers and saved them more than 30 minutes per route.

© 2024 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed without permission.

Citation:
Amazon says new technology in delivery vans will help sort packages on the fly and save time (2024, October 9)
retrieved 9 October 2024
from https://techxplore.com/news/2024-10-amazon-technology-delivery-vans-packages.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.





Source link

Tsuchinshan-Atlas comet visible with naked eye this month

0
Tsuchinshan-Atlas comet visible with naked eye this month


A rare comet brightens the night skies in October
This photo provided by Nicolas Biver shows Comet C/2023 A3 (ATLAS-Tsuchinshan) as seen from Eure-et-Loir, France, June 6, 2024. Credit: Nicolas Biver via AP

Prepare to spot a rare, bright comet. The space rock is slinging toward Earth from the outer reaches of the solar system and will make its closest pass on Saturday. It should be visible through the end of October, clear skies permitting.

Comet Tsuchinshan-Atlas should be bright enough to see with the naked eye, but binoculars and telescopes will give a better view.

“It’ll be this fuzzy circle with a long tail stretching away from it,” said Sally Brummel, planetarium manager at the Bell Museum in Minnesota.

What is a comet?

Comets are frozen leftovers from the solar system’s formation billions of years ago. They heat up as they swing toward the sun, releasing their characteristic streaming tails.

In 2023, a green comet that last visited Earth 50,000 years ago zoomed by the planet again. Other notable flybys included Neowise in 2020, and Hale-Bopp and Hyakutake in the mid to late 1990s.

Where did comet Tsuchinshan-Atlas come from?

The comet, also designated C/2023 A3, was discovered last year and is named for the observatories in China and South Africa that spied it.

A rare comet brightens the night skies in October
This image provided by Patrick Ditz shows two views of comet C/2023 A3 with bars added to indicate it’s angular size, seen from San Pedro de Atacama, Chile, Sept. 24, 2024. Credit: Patrick Ditz via AP

It came from what’s known as the Oort Cloud well beyond Pluto. After making its closest approach about 44 million miles (71 million kilometers) of Earth, it won’t return for another 80,000 years—assuming it survives the trip.

Several comets are discovered every year, but many burn up near the sun or linger too far away to be visible without special equipment, according to Larry Denneau, a lead researcher with the Atlas telescope that helped discover the comet.

A rare comet brightens the night skies in October
This photo provided by Nicolas Biver shows Comet C/2023 A3 (ATLAS-Tsuchinshan) as seen in the night sky of Granada, Spain, on Tuesday, Oct. 1, 2024. Credit: Nicolas Biver via AP

How to view the comet

Those hoping to spot comet Tsuchinshan-Atlas should venture outside about an hour after sunset on a clear night and look to the west.

The comet should be visible from both the northern and southern hemispheres.

© 2024 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed without permission.

Citation:
Tsuchinshan-Atlas comet visible with naked eye this month (2024, October 9)
retrieved 9 October 2024
from https://phys.org/news/2024-10-tsuchinshan-atlas-comet-visible-naked.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.





Source link