In response to a new law, the ride-hail service shows California drivers where a ride would go and how much it would pay. Drivers are learning when to say “No.”
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Tuesday, February 18, 2020
Monday, February 17, 2020
Correcting the “jitters” in quantum devices
Labs around the world are racing to develop new computing and sensing devices that operate on the principles of quantum mechanics and could offer dramatic advantages over their classical counterparts. But these technologies still face several challenges, and one of the most significant is how to deal with “noise” — random fluctuations that can eradicate the data stored in such devices.
A new approach developed by researchers at MIT could provide a significant step forward in quantum error correction. The method involves fine-tuning the system to address the kinds of noise that are the most likely, rather than casting a broad net to try to catch all possible sources of disturbance.
The analysis is described in the journal Physical Review Letters, in a paper by MIT graduate student David Layden, postdoc Mo Chen, and professor of nuclear science and engineering Paola Cappellaro.
“The main issues we now face in developing quantum technologies are that current systems are small and noisy,” says Layden. Noise, meaning unwanted disturbance of any kind, is especially vexing because many quantum systems are inherently highly sensitive, a feature underlying some of their potential applications.
And there’s another issue, Layden says, which is that quantum systems are affected by any observation. So, while one can detect that a classical system is drifting and apply a correction to nudge it back, things are more complicated in the quantum world. “What's really tricky about quantum systems is that when you look at them, you tend to collapse them,” he says.
Classical error correction schemes are based on redundancy. For example, in a communication system subject to noise, instead of sending a single bit (1 or 0), one might send three copies of each (111 or 000). Then, if the three bits don’t match, that shows there was an error. The more copies of each bit get sent, the more effective the error correction can be.
The same essential principle could be applied to adding redundancy in quantum bits, or “qubits.” But, Layden says, “If I want to have a high degree of protection, I need to devote a large part of my system to doing these sorts of checks. And this is a nonstarter right now because we have fairly small systems; we just don’t have the resources to do particularly useful quantum error correction in the usual way.” So instead, the researchers found a way to target the error correction very narrowly at the specific kinds of noise that were most prevalent.
The quantum system they’re working with consists of carbon nuclei near a particular kind of defect in a diamond crystal called a nitrogen vacancy center. These defects behave like single, isolated electrons, and their presence enables the control of the nearby carbon nuclei.
But the team found that the overwhelming majority of the noise affecting these nuclei came from one single source: random fluctuations in the nearby defects themselves. This noise source can be accurately modeled, and suppressing its effects could have a major impact, as other sources of noise are relatively insignificant.
“We actually understand quite well the main source of noise in these systems,” Layden says. “So we don'’ have to cast a wide net to catch every hypothetical type of noise.”
The team came up with a different error correction strategy, tailored to counter this particular, dominant source of noise. As Layden describes it, the noise comes from “this one central defect, or this one central ‘electron,’ which has a tendency to hop around at random. It jitters.”
That jitter, in turn, is felt by all those nearby nuclei, in a predictable way that can be corrected.
“The upshot of our approach is that we’re able to get a fixed level of protection using far fewer resources than would otherwise be needed,” he says. “We can use a much smaller system with this targeted approach.”
The work so far is theoretical, and the team is actively working on a lab demonstration of this principle in action. If it works as expected, this could make up an important component of future quantum-based technologies of various kinds, the researchers say, including quantum computers that could potentially solve previously unsolvable problems, or quantum communications systems that could be immune to snooping, or highly sensitive sensor systems.
“This is a component that could be used in a number of ways,” Layden says. “It’s as though we’re developing a key part of an engine. We’re still a ways from building a full car, but we’ve made progress on a critical part.”
"Quantum error correction is the next challenge for the field," says Alexandre Blais, a professor of physics at the University of Sherbrooke, in Canada, who was not associated with this work. "The complexity of current quantum error correcting codes is, however, daunting as they require a very large number of qubits to robustly encode quantum information."
Blais adds, "We have now come to realize that exploiting our understanding of the devices in which quantum error correction is to be implemented can be very advantageous. This work makes an important contribution in this direction by showing that a common type of error can be corrected for in a much more efficient manner than expected. For quantum computers to become practical we need more ideas like this."
The research was supported by the U.S. Army Research Office and the National Science Foundation.
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Ne-Yo and wife Crystal Renay are divorcing after four years of marriage
Ne-Yo has confirmed he is splitting from his wife after four years of marriage.
The R&B crooner announced in an interview on Saturday, Feb. 15, that he and wife Crystal Renay are divorcing after rumors about their split began to circulate online last week.
“It’s slowly but surely becoming public knowledge that myself and my wife have decided to go ahead and get a divorce,” he said on the “Private Talk With Alexis Texas” podcast, Us Weekly reported.
READ MORE: Common opens up about the emotional pain of his break-up with Erykah Badu
“It’s not a sad thing, it’s more of us realizing that — long story short, I’m never gonna talk bad about her. I’m not that person. There’s nothing bad to say about her. She’s a fantastic woman. She’s the mother of my children and she’s always gonna be that and I will always respect her,” Ne-Yo added.
He wants fans to know that the divorce is not the result of infidelity or the work of outside forces. It seems their individual demons could no longer co-exist.
“Long story short, she’s got demons just like everybody else, just like me,” he continued. “We realize that our demons don’t mesh and until both of us get a hold of our personal demons, it’s gonna be just difficult for us to stay married.”
READ MORE: California school district names elementary school after Michelle Obama
News of their separation was first reported by The Jasmine Brand, with an insider telling the gossip site that Ne-Yo and Renay have been having major issues for a while now.
“With that being said, that’s that, that’s the end of that chapter, not the end of the book,” added Ne-Yo during the podcast interview. “Like I said, that’s the mother of my kids and I love her to death. We’re going to be family forever.”
He also noted that his upcoming new single titled “Pinky Ring” was inspired by his ex.
“The song is not a diss to her, the song is not about her,” he explained. “The song is about how I chose to handle the situation, the way that I chose to lift myself up and keep moving, as we all must do.”
In response, Renay appeared to troll her ex by posting a clip on IG of her with a man rocking a ring on his pinky finger, who she asks to be her Valentine’s date.
Ne-Yo and Renay tied the knot 2016 and share two sons, Shaffer, 3, and Roman, 20 months. He is also father to 9-year-old Madilyn and 8-year-old Mason from his previous relationship with Monyetta Shaw.
The post Ne-Yo and wife Crystal Renay are divorcing after four years of marriage appeared first on TheGrio.
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OPINION: Michael Bloomberg has best plan to close the achievement gap in our schools
We are failing to prepare poor kids across the country for success in school, putting them at a disadvantage for the rest of their lives. The school readiness gap between children coming from low-income and moderate- to high-income households is stark. While 75% of kids from moderate- to high-income families are ready for school at age five, less than 48% of poor kids are. We can and must do better to ensure every child in every zip code has the opportunity to realize their full potential.
Based on my experience as an educator working with children and families in Harlem for the past 30 years, I believe we must take a holistic approach to prepare young people for success in school, starting at birth. It is essential to help first-time parents learn the skills they need to properly care for their babies and help their toddlers build their vocabulary. We also need to open more high-quality early education programs in distressed communities. Students who go to high-quality early education programs are less likely to require special education or repeat a grade and are more likely to graduate from high school than other children.
READ MORE: EXCLUSIVE: Here is why Black educator Geoffrey Canada endorsed Mike Bloomberg
Democratic presidential candidate Mike Bloomberg recently outlined a comprehensive set of plans to help working families and improve child care and early childhood education across the United States. Bloomberg will give all new parents 12 weeks of paid family leave so that they can take time away from work to bond with their newborns or adopted children. He also will expand the federal government’s Maternal, Infant, and Early Childhood Home Visiting Program so that more low-income families can benefit from free and voluntary home visits by trained nurses. Nurse home visits reduce maternal and child mortality rates. In addition, Bloomberg will provide grants to states to help promote language learning programs for young children that will narrow the school readiness gap.
Bloomberg will make sure working families have access to quality, affordable child care. He wants to provide more low-income families with free child care by expanding funding for Early Head Start and Head Start, with the goal of tripling the number of infants and toddlers in Early Head Start and ensuring more three- to five-year-olds who are eligible for Head Start are able to participate. Bloomberg also knows there’s a shortage of quality child care providers in distressed communities around the country. 56% of urban neighborhoods do not have enough licensed child care options. That’s why he will fund programs to help child care providers scale up their businesses in distressed communities as part of his $70 billion investment in the 100 most disadvantaged communities in America.
READ MORE: Joy Ann Reid on Bloomberg: Dems need nominee to ‘fight like a Republican’
Under Bloomberg’s plan, every family will have access to full-day preschool for their three- and four-year-olds. Bloomberg will incentivize states to provide universal access to pre-Kindergarten. States that increase enrollment of low- to moderate-income students and enhance the quality of early childhood education programs will be rewarded. Like me, Bloomberg is deeply concerned that the U.S. government’s spending on early childhood education ranks near the bottom among developed countries. As president, he will work with Congress to ensure our government makes a much greater investment in our nation’s young people.
I worked with Bloomberg on a number of initiatives during his time as New York City’s mayor. Although we didn’t agree on every policy he pursued, I never doubted his commitment to improving our education system and creating more opportunities for all New Yorkers. After reviewing his latest plans, I’m confident Bloomberg will take the steps we need to narrow the school readiness gap across the country and set up our young people for success in the classroom and beyond.
Geoffrey Canada is the founder of the Harlem Children’s Zone. He represents himself and is not representing the views of the Harlem Children’s Zone, which does not endorse any candidates for public office. He has endorsed Mike Bloomberg for president.
The post OPINION: Michael Bloomberg has best plan to close the achievement gap in our schools appeared first on TheGrio.
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PayPal SVP Peggy Alford Works Hard at Letting People Get to Know Her at Work
Featuring a broad cross-section of women who have distinguished themselves across a rich variety of careers, our Portraits of Power series is a celebration of the 50th Anniversary of Black Enterprise, and of black women. It’s a place for today’s businesswomen to share their own favorite images and their own stories, in their own words. Today’s portrait is Peggy Alford, a senior vice president at PayPal and the first black woman to sit on Facebook’s board of directors.
Peggy Alford
SVP, Core Markets, PayPal
My first job was at Big Al’s hamburger joint in a shopping mall in St. Louis. I was a cashier and had to make hand dipped ice cream shakes.
My big break came when eBay, where I was working, bought a company called Rent.com and they asked me to be CFO.
I’ve had to work hardest at letting people get to know me personally at work.
I never imagined I would have three boys.
I wish I’d learned to accept help from others sooner.
The risk I regret not taking is I never pursued a competitive university.
If I could design my fantasy self-care day, it would be spent with good girlfriends, hike, spa, good food and lots of wine.
Trying to balance all my priorities at work and home keeps me up at night.
When I’m struggling, I say to myself, I can do anything for (xx) amount of time.
I am unapologetically reserved.
Portraits of Power is a yearlong series of candid insights from exceptional women leaders. It is brought to you by ADP.
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