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China Roundup: Tencents new US gaming studio and WeChats new paywall

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Hello and welcome back to TechCrunch’s China Roundup, a digest of recent events shaping the Chinese tech landscape and what they mean to people in the rest of the world.

The spotlight this week is back on Tencent, which has made some interesting moves in gaming and content publishing. There will be no roundup next week as China observes the Lunar New Year, but the battle only intensifies for the country’s internet giants, particularly short-video rivals Douyin (TikTok’s Chinese version) and Kuaishou, which will be vying for user time over the big annual holiday. We will surely cover that when we return.

‘Honor of Kings’ creator hiring for U.S. studio

Tencent’s storied gaming studio TiMi is looking to accelerate international expansion by tripling its headcount in the U.S. in 2020, the studio told TechCrunch this week, though it refused to reveal the exact size of its North American office. Eleven-year-old TiMi currently has a team working out of Los Angeles on global business and plans to grow it into a full development studio that “helps us understand Western players and gives us a stronger global perspective,” said the studio’s international business director Vincent Gao.

Gao borrowed the Chinese expression “riding the wind and breaking the wave” to characterize TiMi’s global strategy. The wind, he said, “refers to the ever-growing desire for quality by mobile gamers.” Breaking the wave, on the other hand, entails TiMi applying new development tools to building high-budget, high-quality AAA mobile games.

The studio is credited for producing one of the world’s most-played mobile games, Honor of Kings, a mobile multiplayer online battle arena (MOBA) game, and taking it overseas under the title Arena of Valor. Although Arena of Valor didn’t quite take off in Western markets, it has done well in Southeast Asia in part thanks to Tencent’s publishing partnership with the region’s internet giant Garena.

Honor of Kings and a few other Tencent games have leveraged the massive WeChat and QQ messengers to acquire users. That raises the question of whether Tencent can replicate its success in overseas markets where its social apps are largely absent. But TiMi contended that these platforms are not essential to a game’s success. “TiMi didn’t succeed in China because of WeChat and QQ. It’s not hard to find examples of games that didn’t succeed even with [support from] WeChat and QQ.”

Call of Duty: Mobile is developed by Tencent and published by Activision Blizzard (Image: Call of Duty: Mobile via Twitter) 

When it comes to making money, TiMi has from the outset been a strong proponent of game-as-a-service whereby it continues to pump out fresh content after the initial download. Gao believes the model will gain further traction in 2020 as it attracts old-school game developers, which were accustomed to pay-to-play, to follow suit.

All eyes are now on TiMi’s next big move, the mobile version of Activision Blizzard’s Call of Duty. Tencent, given its experience in China’s mobile-first market, appears well-suited to make the mobile transition for the well-loved console shooter. Developed by Tencent and published by Blizzard, in which Tencent owns a minority stake, in September, Call of Duty: Mobile had a spectacular start, recording more worldwide downloads in a single quarter than any mobile game except Pokémon GO, which saw its peak in Q3 2016, according to app analytics company Sensor Tower.

The pedigreed studio has in recent times faced more internal competition from its siblings inside Tencent, particularly the Lightspeed Quantum studio, which is behind the successful mobile version of PlayerUnknown’s Battlegrounds (PUBG). While Tencent actively fosters internal rivalry between departments, Gao stressed that TiMi has received abundant support from Tencent on the likes of publishing, business development and legal matters.

WeChat erects a paywall – with Apple tax

Ever since WeChat rolled out its content publishing function — a Facebook Page equivalent named the Official Account — back in 2012, articles posted through the social networking platform have been free to read. That’s finally changing.

This week, WeChat announced that it began allowing a selected group of authors to put their articles behind a paywall in a trial period. The launch is significant not only because it can inspire creators by helping them eke out additional revenues, but it’s also a reminder of WeChat’s occasionally fraught relationship with Apple.

WeChat launched its long-awaited paywall for articles published on its platform 

Let’s rewind to 2017 when WeChat, in a much-anticipated move, added a “tipping” feature to articles published on Official Account. The function was meant to boost user engagement and incentivize writers off the back of the popularity of online tipping in China. On live streaming platforms, for instance, users consume content for free but many voluntarily send hosts tips and virtual gifts worth from a few yuan to the hundreds.

WeChat said at the time that all transfers from tipping would go toward the authors, but Apple thought otherwise, claiming that such tips amounted to “in-app purchases” and thus entitled it to a 30% cut from every transaction, or what is widely known as the “Apple tax.”

WeChat disabled tipping following the clash over the terms but reintroduced the feature in 2018 after reaching consensus with Apple. The function has been up and running since then and neither WeChat nor Apple charged from the transfers, a spokesperson from WeChat confirmed with TechCrunch.

If the behemoths’ settlement over tipping was a concession on Apple’s end, Tencent has budged on paywalls this time.

Unlike tipping, the new paywall feature entitles Apple to its standard 30% cut of in-app transactions. That means transfers for paid content will go through Apple’s in-app purchase (IAP) system rather than WeChat’s own payments tool, as is the case with tipping. It also appears that only users with a Chinese Apple account are able to pay for WeChat articles. TechCrunch’s attempt to purchase a post using a U.S. Apple account was rejected by WeChat on account of the transaction “incurring risks or not paying with RMB.”

The launch is certainly a boon to creators who enjoy a substantial following, although many of them have already explored third-party platforms for alternative commercial possibilities beyond the advertising and tipping options that WeChat enables. Zhishi Xingqiu, the “Knowledge Planet”, for instance, is widely used by WeChat creators to charge for value-added services such as providing readers with exclusive industry reports. Xiaoe-tong, or “Smart Little Goose”, is a popular tool for content stars to roll out paid lessons.

Not everyone is bullish on the new paywall. One potential drawback is it will drive down traffic and discourage advertisers. Others voice concerns that the paid feature is vulnerable to exploitation by clickbait creators. On that end, WeChat has restricted the application to the function only to accounts that are over three months old, have published at least three original articles and have seen no serious violations of WeChat rules.

Read more: https://techcrunch.com/2020/01/19/china-roundup-wechat-paywall-tencent-us-game-studio/

Quantum

Sense, sensibility, and superconductors

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Jonathan Monroe disagreed with his PhD supervisor—with respect. They needed to measure a superconducting qubit, a tiny circuit in which current can flow forever. The qubit emits light, which carries information about the qubit’s state. Jonathan and Kater intensify the light using an amplifier. They’d fabricated many amplifiers, but none had worked. Jonathan suggested changing their strategy—with a politeness to which Emily Post couldn’t have objected. Jonathan’s supervisor, Kater Murch, suggested repeating the protocol they’d performed many times.

“That’s the definition of insanity,” Kater admitted, “but I think experiment needs to involve some of that.”

I watched the exchange via Skype, with more interest than I’d have watched the Oscars with. Someday, I hope, I’ll be able to weigh in on such a debate, despite working as a theorist. Someday, I’ll have partnered with enough experimentalists to develop insight.

I’m partnering with Jonathan and Kater on an experiment that coauthors and I proposed in a paper blogged about here. The experiment centers on an uncertainty relation, an inequality of the sort immortalized by Werner Heisenberg in 1927. Uncertainty relations imply that, if you measure a quantum particle’s position, the particle’s momentum ceases to have a well-defined value. If you measure the momentum, the particle ceases to have a well-defined position. Our uncertainty relation involves weak measurements. Weakly measuring a particle’s position doesn’t disturb the momentum much and vice versa. We can interpret the uncertainty in information-processing terms, because we cast the inequality in terms of entropies. Entropies, described here, are functions that quantify how efficiently we can process information, such as by compressing data. Jonathan and Kater are checking our inequality, and exploring its implications, with a superconducting qubit.

With chip

I had too little experience to side with Jonathan or with Kater. So I watched, and I contemplated how their opinions would sound if expressed about theory. Do I try one strategy again and again, hoping to change my results without changing my approach? 

At the Perimeter Institute for Theoretical Physics, Masters students had to swallow half-a-year of course material in weeks. I questioned whether I’d ever understand some of the material. But some of that material resurfaced during my PhD. Again, I attended lectures about Einstein’s theory of general relativity. Again, I worked problems about observers in free-fall. Again, I calculated covariant derivatives. The material sank in. I decided never to question, again, whether I could understand a concept. I might not understand a concept today, or tomorrow, or next week. But if I dedicate enough time and effort, I chose to believe, I’ll learn.

My decision rested on experience and on classes, taught by educational psychologists, that I’d taken in college. I’d studied how brains change during learning and how breaks enhance the changes. Sense, I thought, underlay my decision—though expecting outcomes to change, while strategies remain static, sounds insane.

Old cover

Does sense underlie Kater’s suggestion, likened to insanity, to keep fabricating amplifiers as before? He’s expressed cynicism many times during our collaboration: Experiment needs to involve some insanity. The experiment probably won’t work for a long time. Plenty more things will likely break. 

Jonathan and I agree with him. Experiments have a reputation for breaking, and Kater has a reputation for knowing experiments. Yet Jonathan—with professionalism and politeness—remains optimistic that other methods will prevail, that we’ll meet our goals early. I hope that Jonathan remains optimistic, and I fancy that Kater hopes, too. He prophesies gloom with a quarter of a smile, and his record speaks against him: A few months ago, I met a theorist who’d collaborated with Kater years before. The theorist marveled at the speed with which Kater had operated. A theorist would propose an experiment, and boom—the proposal would work.

Sea monsters

Perhaps luck smiled upon the implementation. But luck dovetails with the sense that underlies Kater’s opinion: Experiments involve factors that you can’t control. Implement a protocol once, and it might fail because the temperature has risen too high. Implement the protocol again, and it might fail because a truck drove by your building, vibrating the tabletop. Implement the protocol again, and it might fail because you bumped into a knob. Implement the protocol a fourth time, and it might succeed. If you repeat a protocol many times, your environment might change, changing your results.

Sense underlies also Jonathan’s objections to Kater’s opinions. We boost our chances of succeeding if we keep trying. We derive energy to keep trying from creativity and optimism. So rebelling against our PhD supervisors’ sense is sensible. I wondered, watching the Skype conversation, whether Kater the student had objected to prophesies of doom as Jonathan did. Kater exudes the soberness of a tenured professor but the irreverence of a Californian who wears his hair slightly long and who tattooed his wedding band on. Science thrives on the soberness and the irreverence.

Green cover

Who won Jonathan and Kater’s argument? Both, I think. Last week, they reported having fabricated amplifiers that work. The lab followed a protocol similar to their old one, but with more conscientiousness. 

I’m looking forward to watching who wins the debate about how long the rest of the experiment takes. Either way, check out Jonathan’s talk about our experiment if you attend the American Physical Society’s March Meeting. Jonathan will speak on Thursday, March 5, at 12:03, in room 106. Also, keep an eye out for our paper—which will debut once Jonathan coaxes the amplifier into synching with his qubit.

Source: https://quantumfrontiers.com/2020/02/23/sense-sensibility-and-superconductors/

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Quantum

Approximating Hamiltonian dynamics with the Nyström method

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Alessandro Rudi1, Leonard Wossnig2,3, Carlo Ciliberto2, Andrea Rocchetto2,4,5, Massimiliano Pontil6, and Simone Severini2

1INRIA – Sierra project team, Paris, France
2Department of Computer Science, University College London, London, United Kingdom
3Rahko Ltd., London, United Kingdom
4Department of Computer Science, University of Texas at Austin, Austin, United States
5Department of Computer Science, University of Oxford, Oxford, United Kingdom
6Computational Statistics and Machine Learning, IIT, Genoa, Italy

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Abstract

Simulating the time-evolution of quantum mechanical systems is BQP-hard and expected to be one of the foremost applications of quantum computers. We consider classical algorithms for the approximation of Hamiltonian dynamics using subsampling methods from randomized numerical linear algebra. We derive a simulation technique whose runtime scales polynomially in the number of qubits and the Frobenius norm of the Hamiltonian. As an immediate application, we show that sample based quantum simulation, a type of evolution where the Hamiltonian is a density matrix, can be efficiently classically simulated under specific structural conditions. Our main technical contribution is a randomized algorithm for approximating Hermitian matrix exponentials. The proof leverages a low-rank, symmetric approximation via the Nyström method. Our results suggest that under strong sampling assumptions there exist classical poly-logarithmic time simulations of quantum computations.

► BibTeX data

► References

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Cited by

[1] Ewin Tang, “Quantum-inspired classical algorithms for principal component analysis and supervised clustering”, arXiv:1811.00414.

[2] Juan A. Acebron, “A Monte Carlo method for computing the action of a matrix exponential on a vector”, arXiv:1904.12759.

[3] Nai-Hui Chia, András Gilyén, Tongyang Li, Han-Hsuan Lin, Ewin Tang, and Chunhao Wang, “Sampling-based sublinear low-rank matrix arithmetic framework for dequantizing quantum machine learning”, arXiv:1910.06151.

The above citations are from SAO/NASA ADS (last updated successfully 2020-02-20 15:40:36). The list may be incomplete as not all publishers provide suitable and complete citation data.

Could not fetch Crossref cited-by data during last attempt 2020-02-20 15:40:34: Could not fetch cited-by data for 10.22331/q-2020-02-20-234 from Crossref. This is normal if the DOI was registered recently.

Source: https://quantum-journal.org/papers/q-2020-02-20-234/

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Quantum

Extension of the Alberti-Ulhmann criterion beyond qubit dichotomies

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Michele Dall’Arno1,2, Francesco Buscemi3, and Valerio Scarani1,4

1Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, 117543, Singapore
2Faculty of Education and Integrated Arts and Sciences, Waseda University, 1-6-1 Nishiwaseda, Shinjuku-ku, Tokyo 169-8050, Japan
3Graduate School of Informatics, Nagoya University, Chikusa-ku, 464-8601 Nagoya, Japan
4Department of Physics, National University of Singapore, 2 Science Drive 3, 117542, Singapore

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Abstract

The Alberti-Ulhmann criterion states that any given qubit dichotomy can be transformed into any other given qubit dichotomy by a quantum channel if and only if the testing region of the former dichotomy includes the testing region of the latter dichotomy. Here, we generalize the Alberti-Ulhmann criterion to the case of arbitrary number of qubit or qutrit states. We also derive an analogous result for the case of qubit or qutrit measurements with arbitrary number of elements. We demonstrate the possibility of applying our criterion in a semi-device independent way.

As soon as entanglement was recognised as a resource, theorists started studying the interconversions properties of this resource. The most famous such question is: given N copies of a state rho, how many copies N’ of the state rho’ can one obtain with local operations and classical communication? This question led to the definition of entanglement of formation (rho is the maximally entangled state), of distillation (rho’ is the maximally entangled state), to the discovery of inequivalent entanglement classes for multipartite systems… The amount of literature on this question is enormous.

Very little however is known about a different problem, the one we consider here. The question is whether a pair of states (rho,sigma) can be converted into another pair of states (rho’,sigma’). This question does not need to refer to entanglement: in fact, here we don’t consider composite systems, and consequently we don’t restrict the possible operations. A very simple answer would be the one that holds for classical probability distributions: Pair 1 can be converted into Pair 2, if all the statistics that can be observed with Pair 2 can also be observed with Pair 1. This conveys the idea that Pair 1 can do all that Pair 2 can do, and possibly more. This answer holds for two states of qubits (Alberti and Uhlmann, 1980), but counter-examples are known already when Pair 1 comprises qutrit states. In this paper, we prove that the classical-like characterisation still holds when Pair 1 is generalized to any family of qubit states, as soon as they can all be expressed with real coefficients, and Pair 2 is generalized to any family of qubit or, under certain hypotheses, qutrit, states. We also exploit a duality between states and measurements to present a similar characterisation of measurement devices.

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