adplus-dvertising
Connect with us

Science

Deciphering Quantum Complexity: A Pioneering Algorithm for Accurate Qubit Calculation – SciTechDaily

Published

 on


Scientists have developed the ACE algorithm to study qubit interactions and changes in their quantum state, simplifying quantum dynamics computation and paving the way for advancements in quantum computing and telephony.

Practical quantum computing is another step closer.

Researchers have introduced a novel algorithm called Automated Compression of Arbitrary Environments (ACE) designed to study the interactions of qubits with their surrounding environment and the ensuing changes in their quantum state. By simplifying the computation of quantum dynamics, this algorithm, grounded on Feynman’s interpretation of quantum mechanics, offers new avenues for understanding and harnessing quantum systems. Potential applications include advancements in quantum telephony and computing, providing more precise predictions about quantum coherence and entanglement.

Conventional computers use bits, represented by zeros and ones, to transmit information, whereas quantum computers use quantum bits (qubits) instead. Similar to bits, qubits have two main states or values: 0 and 1. However, unlike a bit, a qubit can exist in both states at the same time.

While this may seem like a baffling paradox, it can be explained through a simple analogy with a coin. A classic bit can be represented as a coin lying with heads or tails (one or zero) facing up, while a qubit can be thought of as a spinning coin, which also has heads and tails, but whether it is heads or tails up can only be determined once it stops spinning, ie loses its original state.

When a spinning coin stops, it can serve as an analogy for a quantum measurement, whereby one of the two states of the qubit is selected. In <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

quantum computing
Performing computation using quantum-mechanical phenomena such as superposition and entanglement.

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>quantum computing, different qubits must be linked together, eg the states 0 (1) of one qubit must be uniquely correlated with the states 0 (1) of another qubit. When the quantum states of two or more objects become correlated, it is called quantum entanglement.

The Challenge of Quantum Entanglement

The main difficulty with quantum computing is that qubits are surrounded by an environment and interact with them. This interaction can cause the quantum entanglement of qubits to degrade, resulting in their disentanglement from one another.

An analogy with two coins can help in understanding this concept. If two identical coins are spun simultaneously and then stopped after a brief period, they may both end up with the same side up, either heads or tails. This synchronicity between spinning coins can be compared to quantum entanglement. However, if the coins continue to spin for a longer duration, they will eventually lose synchronicity and no longer end up with the same side—heads or tails—facing up.

The loss of synchronicity occurs because the spinning coins gradually lose energy, mainly due to friction with the table, and each coin does so in a unique manner. In the quantum world, friction, or the loss of energy due to interaction with the environment, eventually leads to quantum decoherence, meaning a loss of synchronicity between qubits. This results in qubit dephasing, where the phase of the quantum state (represented by the angle of rotation of the coin) changes randomly over time, causing a loss of quantum information and making quantum computing impossible.

ACE Approach

Identification of an efficient representation is fully automatic and does not rely on any a priori approximations or assumptions. Credit: Alexei Vagov

Quantum Coherence and Dynamics

A key challenge faced by many researchers today is to preserve quantum coherence for longer periods. This can be achieved by accurately describing the evolution of the quantum state over time, also known as quantum dynamics.

Scientists from the MIEM HSE Centre for Quantum Metamaterials, in collaboration with colleagues from Germany and the UK, have proposed an algorithm called Automated Compression of Arbitrary Environments (ACE) as a solution for studying the interaction of qubits with their environment and the resulting changes in their quantum state over time.

Insight into Quantum Dynamics

“The almost infinite number of vibrational modes or degrees of freedom in the environment makes the computation of quantum dynamics particularly challenging. In fact, this task involves computing the dynamics of a single quantum system while it is surrounded by trillions of others. Direct calculation is impossible in this case, as no computer can handle it.

However, not all changes in the environment carry equal importance: those which occur at a sufficient distance from our quantum system are incapable of affecting its dynamics in major ways. The division into “relevant” and “irrelevant” environmental degrees of freedom lies at the basis of our method,” says Alexei Vagov, co-author of the paper, Director of the MIEM HSE Centre for Quantum Metamaterials.

Feynman’s Interpretation and the ACE Algorithm

According to the interpretation of quantum mechanics proposed by the famous American physicist Richard Feynman, calculating the quantum state of a system involves computing the sum of all possible ways in which the state can be achieved. This interpretation assumes that a quantum particle (system) can move in all possible directions, including forward or backward, right or left, and even back in time. The quantum probabilities of all such trajectories must be added up to compute the final state of the particle.

“The problem is that there are too many possible trajectories even for one particle, let alone the entire environment. Our algorithm makes it possible to consider only the trajectories which significantly contribute to the qubit’s dynamics while discarding those with negligible contributions. In our method, the evolution of a qubit and its environment is captured by tensors, which are matrices or tables of numbers that describe the state of the entire system at different points in time. We then select only those portions of the tensors which are relevant to the system’s dynamics,” explains Alexei Vagov.

Conclusion: Implications of the ACE Algorithm

The researchers emphasize that the Automated Compression of Arbitrary Environments algorithm is publicly available and implemented as computer code. According to the authors, it opens up entirely new possibilities for the precise computation of the dynamics of multiple quantum systems. In particular, this method makes it possible to estimate the time until entangled <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

photon
A photon is a particle of light. It is the basic unit of light and other electromagnetic radiation, and is responsible for the electromagnetic force, one of the four fundamental forces of nature. Photons have no mass, but they do have energy and momentum. They travel at the speed of light in a vacuum, and can have different wavelengths, which correspond to different colors of light. Photons can also have different energies, which correspond to different frequencies of light.

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>photon pairs in quantum telephony lines will become disentangled, the distance to which a quantum particle can be “teleported,” or how long it can take for the qubits of a quantum computer to lose coherence.

Reference: “Simulation of open quantum systems by automated compression of arbitrary environments” by Moritz Cygorek, Michael Cosacchi, Alexei Vagov, Vollrath Martin Axt, Brendon W. Lovett, Jonathan Keeling and Erik M. Gauger, 24 March 2022, <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

Nature Physics
As the name implies, Nature Physics is a peer-reviewed, scientific journal covering physics and is published by Nature Research. It was first published in October 2005 and its monthly coverage includes articles, letters, reviews, research highlights, news and views, commentaries, book reviews, and correspondence.

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>Nature Physics.
DOI: 10.1038/s41567-022-01544-9

Adblock test (Why?)

728x90x4

Source link

Continue Reading

News

Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

Published

 on

 

More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

___

Follow AP’s climate coverage at https://apnews.com/hub/climate

___

Follow Seth Borenstein on Twitter at @borenbears

___

Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

Source link

Continue Reading

Science

‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

Published

 on

 

It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

Source link

Continue Reading

News

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

Published

 on

 

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.

Source link

Continue Reading

Trending