Cloud Hosting

Youre probably quite familiar with the basic states of mattersolid, liquid, gasthat fill everyday life on Earth.

But those three different sorts of matter that each look and act differently arent the whole of the universefar from it. Scientists have discovered (or created) dozens of more exotic states of matter, often bearing mystical and fanciful names: superfluids, Bose-Einstein condensates, and neutron-degenerate matter, to name a few.

In the last few years, physicists around the world have been constructing another state of matter: a time crystal. If that seems like B-movie technobabble, its technobabble no longer. Using a quantum computer, a few researchers have created a time crystal that, they think, firmly establishes time crystals in the world of physics.

The researchers havent yet formally published their research, but last month, they posted a preprint (a scientific paper that has yet-to-be peer-edited) on the website ArXiV.

So what exactly is a time crystal? It might sound like the critical component that makes a time machine tick, some sort of futuristic power source, or perhaps an artifact of a lost alien civilization. But, to scientists, a time crystal is actually something more subtle: a curiosity of the laws of physics.

What defines any bog-standard crystalsuch as a diamond, an emerald, or even an ice cubeis that the crystals atoms are somehow arranged in repeating patterns in space. Theres three dimensions of spaceand a fourth dimension, time. So physicists wondered if a crystals atoms could be arranged in repeating patterns in time.

In practice, that works something like this. You create a crystal whose atoms start in one state. If you blast that crystal with a finely tuned laser, those atoms might flip into another stateand then flip backand then flip againand so forth, all without actually absorbing any energy from the laser.

If you step back, what youve just created is a state of matter thats perpetually in motion, indefinitely, without taking in any energy.

Thats no small feat. It beats against one of classical physics most sacred tenets: the second law of thermodynamics. That law states that the amount of entropy, or disorder, always tends to increase. Think of it like a vase, teetering at the edge of a table. The universe wants to push that vase over and make it shatter across the floor. To piece it back together, you have to put in the energy.

Time crystals are actually a rather new idea, having first been theorized by Nobel-winning physicist Franck Wilczek in 2012. Not all physicists accepted that theory at the time, with some claiming that the second law of thermodynamics would rear its legalistic head.

Naturally, determined researchers found loopholes. In 2016, physicists at the University of Maryland managed to bodge together a crude time crystal from a collection of ytterbium atoms. Other groups have created time crystals inside diamonds.

[Related: In photos: a rare glimpse inside the heart of a quantum computer]

But these latest time-crystal-tinkerers did something different. They turned to Google and used a quantum computer: a device that takes advantage of the quirks of quantum mechanics, the seemingly mystical sort of physics that guides the universe at the tiniest scales. Instead of using bits of silicon like everyday, classical computers, quantum computers operate directly with atoms or particles. That allows physicists to do experiments which can be agonizingly difficult with traditional computers, since quantum physicswhich allows particles to be multiple things at one and for particles to interact at seemingly impossible distancesgets quite esoteric.

The ability to simulate the rulesbecomes so much harder with traditional computers, says Gabriel Perdue, a quantum computer researcher at Fermilab, a national lab in suburban Chicago that focuses on high-end particle physics.

But, by arranging particles in a quantum computers processor, its possible to literally study systems of tiny particles as if they are building blocks. Thats a powerful ability, and its not something youll see much in the non-quantum world.

We dont compute, you know, how far a baseball goesby building miniature baseball players and doing simulations, says Perdue. But doing something quite similar on a very small scale, he says, is what the researchers used Googles quantum computer to do to make their time crystal.

In this case, physicists could take atoms, rearrange them, then pulse them with a laser to drive a time crystal. That setup has allowed researchers to create a time crystal thats bigger than any time crystal before it. While many previous time crystals were short-lasting and unravelled within a few back-and-forth flip cycles, the scientists behind this latest time crystal effort are marvelling at the stability of what theyve created.

The thing that is most exciting here, for me, says Perdue, its a demonstration of using a quantum computer to really simulate a quantum physics system and study it in a way that is really novel and exciting.

So, could these time crystals indeed lead to a new wave of nascent time machines?

Probably not. But they might help make quantum computers become more robust. Engineers have struggled for years to create something that could serve as memory in quantum computers; some equivalent to the silicon that underpins traditional computers. Time crystals, physicists think, could serve that purpose.

And this experiment, Perdue says, is also a demonstration of the power of quantum computers to do science. The same platform that makes it easy for you to simulate some cool algorithm, he says, works just as well, and I would argue even better, for simulating these kinds of systems.

Read more:

What the heck is a time crystal, and why are physicists obsessed with them? - Popular Science

Computer science has been named the fastest-growing A-level STEM (science, technology, engineering, mathematics) subject by BCS, the Chartered Institute for IT.

According to the Institutes analysis, results day (10 August) this year saw an 11% increase in the number of students earning an A-level grade in the discipline. Not only this, but more female students than any previous year have achieved a grade in the subject, more than half of whom have been awarded an A or A*.

Compared to last year, the subject saw 13% more female A-level entries, with BCSs research showing that A-level enrolments from young women have increased by more than 350% since 2015.

In Scotland, 17% of computer science highers have been granted to female students this year.

Data shows that women now comprise 15% of all A-level entries and are generally achieving higher grades. More than 51% (compared to 45% in 2020) of female students received a high grade this year, compared to 43% (35% in 2020) of male students.

The Institute has welcomed the rise in female participation, which has subsequently driven a 9% surge in the number of young women pursuing the subject at undergraduate (UG) level across the UK. This trend is mirrored across the whole of this years cohort, which overall, has seen highest number of students being accepted into computer science degrees in the last decade. According to Ucas data, there has been a 5% increase in UG computer science graduates compared to 2020. Over the last 10 years, student demand for the subject has soared by 60%.

Computing is a rich and creative subject which can lead to exciting and rewarding careers, as well as skills which are in high demand from employers, and will help to address the digital skills gap Julia Adamson, BCS

Julia Adamson, director of education at BCS, said: More young people than ever before are choosing to study computer science at university. Computing is a rich and creative subject which can lead to exciting and rewarding careers, as well as skills which are in high demand from employers, and will help to address the digital skills gap.

There are variations across UK countries, with the number of students from England gaining acceptance to computer science degrees increasing by 6%; from Scotland, up 5%; while numbers in Wales remain the same; and enrolments in Northern Ireland have declined by 14%.

The study confirms computer science as the fastest-growing STEM-based A-level, with numbers in England rising by 12%, compared to 6.4% for STEM subjects overall (including: maths and further maths, computer science, biology, physics and chemistry).

Student appetites for the subject are also expanding in Scotland, with the nation seeing a 7% growth in the number of students being awarded a computer science higher.

Were particularly pleased to see rising numbers of female students choosing to study computer science at A-level and as a degree and hope this will lead to an increasingly diverse workforce in tech industries, added Adamson.

Congratulations to everyone receiving their results today. We know students and teaching staff have worked incredibly hard through a challenging year.

In other news: A-level results: increase in STEM entries from girls, but widening participation efforts stall

Read more:

'More young people than ever' choosing computer science at uni, says BCS - Education Technology

The COVID-19 pandemic upended so much so quickly when stay-at-home orders forced most Americans indoors in March 2020. For Penn Law economics professor David Abrams, who has spent the last two decades studying crime, a key question for the moment was how the pandemic would affect Americas crime rate. Would forcing people to stay home lead to calm? Could a sense of detachment lead to lawlessness?

Last summer he launched a series of projects aimed at analyzing data from cities around the nation to get to the bottom of how the pandemic affected crime.

Crime dropped in a big way as the pandemic hit, which turns out to be the same thing that happened 100 years ago during the 1918 flu pandemic. Thats the short-term takeaway, Abrams says.This initial drop in crime has been swept away by the current, headline-grabbing spike in homicides and shootings getting a lot of media attention, but even now not all crimes are up, he says.

There remain deeper takeaways from the pandemics effect on crime to be uncovered, he says. What happens when police stops on the streets get interrupted by pandemics or by protests? What happens when police presence varies?

Those are actually bigger, more important questions ultimately, but theyre ones that take longer to answer. Thats why were still doing the research.

This summer, the projects continue and are getting a boost from two undergraduate interns: Caroline Li, a rising sophomore from Lexington, Massachusetts, studying economics at the Wharton School, and David Feng, a rising sophomore from San Francisco,majoring in computer science in the School of Engineering and Applied Science.

The initial project involves a website Abrams created at the start of the pandemic called City Crime Stats, which started as a way to track crime during lockdown but has since transformed into a site that tracks criminal justice data from 27 major cities across the United States.

Separately, Abrams team is going beyond what happened in the pandemic, looking at the protests that followed the murder of George Floyd and different aspects of crime like police stops. Li and Feng are getting crime data from police departments around the country;removing incorrect, duplicate, or incomplete data; and moving towards analyzing it.

These big changes in such a short period of time offer a chance to learn about what impacts crime in a way that we normally couldnt, Abrams says of COVID and the racial justice rallies and protests of last June. We hope this research will help to expand our basic understanding of what impacts crime.

In high school, Feng was a debater and says he found himself wondering about the backstory of the statistics and data he was using to bolster his arguments. This led to his interest in computer science and analyzing data so he could learn how data was utilized to determine trends in society. Thats also what drew him to Abrams project.

Theres no better time to look at data than now, during COVID. Its such a monumental moment in modern history with social and economic repercussions that ripple all throughout America, says Feng. Seeing that I could use my technical skills to help contribute to this research was really important to me.

As part of his internship Feng has completely redone the City Crime Stats website.

Hes made it much better and much more useful, Abrams says, noting the site has been particularly valuable to journalists. Im really happy with how useful its been to the public, and I think it will be even more so now.

Li was drawn to the internship because she wanted to get a sense of how academic research worked at an institution like Penn. As a high schooler, you dont understand research and having this experience gives a great, broad overview of how academic research at the collegiate level is conducted, she says.

She also liked how timely the topic was, looking at both COVID and the protests and how it let her put her economics background to work. Im interested in trying to use techniques from economics across other fields, so I really appreciated the way that this project allows for that.

Feng echoed that its been helpful getting a sense of how his technical skills can be used in other fields.

Having this experience helped me realize that there are so many applications of technology and computer science, from criminal law to sociology to nonprofits and finance, he says. Theres such a broad-base application of it, and Im really glad that I was able to apply it to something I care about and am passionate about.

The goal for the research projects is to provide information for a number of academic papers, including a working paper on police stops that they recently presented at the National Bureau of Economic Researchs summer meeting, Abrams says.The first paper to emerge from the project, published in January in the Journal of Public Economics, is an early look at the pandemics effect on crime. He envisions a number of other papers will take shape from the project.

Despite the challenges of working together virtually, Li and Feng are making the most of the internships, which are supported by the Penn Undergraduate Research Mentoring Program (PURM).

It's always a pleasure working with PURM students, but these two have been especially fantastic, says Abrams. Its impressive to see what Penn undergrads, with one year of college under their belts, can contribute to ongoing research, and thats something Im very, very happy with.

David S. Abrams is a professor of law, business economics, and public policy at the University of Pennsylvania Carey School of Law and the Wharton School.

This opportunity was offered through the Center for Undergraduate Research & Fellowships, specifically the Penn Undergraduate Research Mentoring Program for first years and sophomores. Each student receives an award of $4,500 for the 10-week summer internship.

See the original post:

COVID-19, protests, and crime | Penn Today - Penn Today - Penn Today