Saturday, November 13, 2021

Markets pull back as inflation soars

Nov. 13, 2021

Here is the link.

CPI was up 6.2% over last October, the biggest gain since 1990. With CNBC's Melissa Lee and the Fast Money traders, Tim Seymour, Karen Finerman, Steve Grasso and Pete Najarian. For access to live and exclusive video from CNBC subscribe to CNBC PRO: https://cnb.cx/2NGeIvi U.S. stock futures were steady in overnight trading on Wednesday following a tech-driven sell-off on Wall Street. Dow futures fell just 25 points. S&P 500 futures were flat and Nasdaq 100 futures rose 0.02%. Disney shares fell 4% in after-hours trading after the media giant missed on the top and bottom lines of its quarterly results. Disney+ subscribers also came in short of estimates. The major averages dipped on Wednesday after a hot inflation report pushed up bond yields. The rise in yields especially pressured growth pockets of the market. The Dow Jones Industrial Average lost 240 points, dragged down by roughly 3% losses in Salesforce and Nike. The S&P 500 fell 0.8%. The Nasdaq Composite was the relative underperformer, dipping 1.7% as Facebook-parent Meta Platforms, Amazon, Apple, Netflix, Microsoft and Google-parent Alphabet all closed lower. The small-cap benchmark Russell 2000 dropped 1.6% on Wednesday. Persistent inflation data was released on Wednesday. The consumer price index, which is a basket of products ranging from gasoline and health care to groceries and rents, rose 6.2% in October from a year ago, hitting its highest level in three decades. On a monthly basis, the CPI increased 0.9% against the 0.6% estimate. “Inflation remains stubbornly high, to the surprise of many that expected prices to come back to earth sooner,” said Ryan Detrick, chief market strategist for LPL Financial. “The truth is you can’t shut down a $20 trillion economy and not feel some bumps as it restarts, but we are hopeful the supply chain issues will resolve over the coming quarters and inflation should calm down as well.” Following the CPI data, traders moved up their expectations for when the first Fed rate hike would occur. The Fed funds futures market now sees greater odds of the central bank’s first full rate hike coming in July 2022. Investors also took refuge in inflation hedges on Wednesday, like gold and bitcoin.

Friday, November 12, 2021

UAL stock: United Adds 44 Flights to Las Vegas for CES 2022

 

United Adds 44 Flights to Las Vegas for CES 2022


Fri, November 12, 2021, 10:00 AM

Airline to add 80% of the capacity it added for CES 2020

CHICAGO, Nov. 12, 2021 /PRNewswire/ -- In response to feedback from its business customers and an uptick in demand, United Airlines is expanding its schedule to make it easier for CES 2022 attendees to join the in-person show in Las Vegas. The airline is adding 14 new direct flights in early January between Las Vegas and San Jose, Calif., Boston, Fort Lauderdale, and Orlando, and is also adding 30 flights from its hub airports in San Francisco, Los Angeles, New York/Newark, and Washington D.C./Dulles. This represents a capacity increase of 37% compared to its usual January schedule to Las Vegas.

"The return of in-person conferences and events is a very positive sign in the pandemic recovery, and United is uniquely positioned to capitalize on this increase in demand," said Ankit Gupta, senior vice president of Domestic Planning and United Express. "We're adding about 80% of the capacity we did for CES in 2020, demonstrating that business travel is on the rebound and our customers are eager to reunite with clients and colleagues."

Between Oct. 27 and Nov. 9, searches on United.com for flights to Las Vegas during CES 2022 were up 70% compared to the prior two-week period. And according to a recent survey of United's business customers, nearly 20% say they expect travel to meetings and conferences will exceed pre-pandemic levels in 2022.

United will fly 81 flights into Las Vegas during the peak arrival days of January 3-4, and 109 flights on the peak departure days of January 8-10. New flights include:

  • 8 direct flights from San Jose, Calif.

  • 6 direct flights from Fort Lauderdale, Boston and Orlando

  • 15 additional flights from San Francisco, and 9 flights on a larger aircraft

  • 8 additional flights from Los Angeles, and 4 flights on a larger aircraft

  • 5 additional flights from Washington D.C./Dulles

  • 2 additional flights from New York/Newark

Tickets for all of these flights are available for sale now at United.com.

Committed to Ensuring a Safe Journey

United is committed to putting health and safety at the forefront of every customer's journey, with the goal of delivering an industry-leading standard of cleanliness through its United CleanPlus℠ program. United has teamed up with Clorox and Cleveland Clinic to redefine cleaning and health safety procedures from check-in to landing and has implemented more than a dozen new policies, protocols and innovations designed with the safety of customers and employees in mind. Customers can review COVID-19 entry requirements, find local testing options and upload any required testing and vaccination records for domestic and international travel, all in United's Travel Ready Center. United was the first airline to integrate all these features into its mobile app and website.

United Next

United is more focused than ever on its commitment to customers and employees. In addition to today's announcement, United has recently:

  • Launched an ambitious plan to transform the United customer experience by adding and upgrading hundreds of aircraft as well as investing in features like larger overhead bins, seatback entertainment in every seat and the industry's fastest available Wi-Fi.

  • Announced a goal to create 25,000 unionized jobs by 2026 that includes careers as pilots, flight attendants, agents, technicians, and dispatchers.

  • Announced that United will train at least 5,000 pilots by 2030 through the United Aviate Academy, with the plan of at least half being women and people of color.

  • Required all U.S. employees to receive a COVID-19 vaccination.

  • Became the first airline to offer customers the ability to check their destination's travel requirements, schedule COVID-19 tests and more on its mobile app and website.

  • Invested in emerging technologies that are designed to decarbonize air travel, like an agreement to work with urban air mobility company Archer, an investment in aircraft startup Heart Aerospace and a purchase agreement with Boom Supersonic.

  • Committed to going 100% green by reducing our greenhouse gas emissions by 100% by 2050, without relying on traditional carbon offsets.

  • Eliminated change fees for all economy and premium cabin tickets for travel within the U.S.


Warren Buffett | Lecture | University Of Florida | 1998

Nov. 12, 2021

Here is the link.

AZN stock: My first purchase after I saw 6% loss on earnings date - Nov 12, 2021

 In AstraZeneca’s earnings report today, the company announced it booked a “modest profit” from Covid-19 vaccine sales.

Over $1 billion of the company’s $9.7 billion in product sales came from the sales of it Covid-19 vaccine. It’s one of the cheapest Covid vaccines in the world, fetching a price between $4-$8 dollars, according to BBC.

The low prices are observably lower than Moderna, Pfizer, and even Johnson & Johnson’s vaccines. 💉 That’s because AstraZeneca chose to supply the vaccine at “no profit.” The company’s CEO, Pascal Soriot, indicated he had “no regrets” about choosing not to take profits while others did.

The company indicated its modest profit would be way less than other drugmakers, because AstraZeneca intend to keep it cheap. Most of the company’s Covid vaccine sales are also expected to support the development of a “Covid-19 antibody combination drug,” which is in clinical trials.

The rest of AstraZeneca’s business saw product revenue growth of 33% YoY. However, the company has booked just $1.35 billion in operating profit YTD, which is 63% lower than FY 2020. Almost all of those numbers are because AstraZeneca prioritized public health over profit.

$AZN fell 6.5% after hours, but the company still deserves a round of applause.

Thursday, November 11, 2021

GTE stock: Five Best Penny Stocks Under $1 To Buy Right Now | Best Stocks Under $1 for November

Nov. 11, 2021

Here is the link.

Stocks are often volatile especially penny stocks that are under $1. In this Video the stocks telegraph team has gathered five best penny stocks under $1 to buy right now. We are entering the last phase of 2021. There are massive opportunities for investors to explore the stock market. We bring the best stocks under $1 for November. $1 stocks can be a good option for those who have a limited budget for investment.  Stock under $1, also known as penny stocks, are a lucrative source of income. With the advancement of social media and platforms like Reddit, the idea of investing in cheap stocks emerged on the global stage.  One-dollar stocks can be volatile as a lot of day traders are involved in investing in $1 stocks. Whilst the volatility of these stocks, cheap stocks can also net some impressive returns in a short time. In other words high returns come with some risk. The stocks we have discussed in this video are Zomedica Corp (ZOM Stock), Gran Tierra Energy (GTE Stock), Avinger Inc (AVGR Stock), SeaChange (SEAC Stock), and AIkido Pharma (AIKI Stock). ___________________________________________________________ ▬ Chapters ▬ 0:00 - Intro 1:04 - Zomedica Corp (ZOM Stock) 2:58 - Gran Tierra Energy (GTE Stock) 5:01 - Avinger Inc (AVGR Stock) 6:38 - SeaChange (SEAC Stock) 8:24 - AIkido Pharma (AIKI Stock)

2 minutes presentation GTE | Data available for analysis

  1. 29,000 barrel/ day | 20% more compared to last quarter
  2. 2021 pay down debt $140 million
  3. Working capital $84.47 million
  4. Blockade was removed after three weeks, and back to normal -> up 7% on Nov. 11
  5. Perfect position in November, 2021
  6. I like to take notes from screen:
  7. In the trailing 12-months, the working capital has increased to $84.47 million.
  8. With production restored, a successful 2021 drilling program, strong world oil prices, Gran looks to be in a perfect position. GTE stock could be a good buy in November.


Sherry invest: How Bill Ackman made 2.6 billion from 27 million

Nov. 11, 2021

Here is the link.  

How Bill Ackman made 2.6 billion from 27 million (~100X Return) & 3 things I learned from him

IONQ stock: Quantum computing stock | 10 days around Nov. 11 over 100% return

 Dear:


The chatting history for this WeChat group "投资小群" is shown below.


————— 2021-11-11 —————

Anne 安娜💐 10:45

Anne 安娜💐 10:46

winnie上周提ionq,当日$11,前天$22

Anne 安娜💐 10:46

仅十天

Anne 安娜💐 10:47

未来不可预测[呲牙]

陈建敏 10:50

我昨天听了量子计算,搞明白了。讲解就是我分享的哈佛博士,清华教授,他打了一个比方,就是在一个十字路口找羊🐑,走哪一条?量子计算就是孙悟空,一个变二个,每条路派一个,同时找。

陈建敏 10:51

这样就提高了速度,可以用在AI, machine learning.

陈建敏 10:52

大家都来听听70岁科学家,台湾人,他讲解通俗易懂。我博士导师偶像。

陈建敏 10:52

IONR stock | 10 days over 100% return | Quantum computing 



👜Tapestry Stock ($TPR) - Why Women Spend More on Handbag during Pandemic?

Nov. 11, 2021

Here is the link. 


Berkeley ACM A.M. Turing Laureate Interviews: Andrew Chi-Chih Yao

Nov. 11, 2021

Here is the link.

Andrew Chi-Chih Yao:The Advent of Quantum Computing-2017Tencent WE Summit

Nov. 11, 2021

Here is the link. 

Andrew Chi-Chih Yao:The Advent of Quantum Computing-2017Tencent WE Summit


Wednesday, November 10, 2021

AMD new chip | Techspot.com | 3rd-gen Epyc server CPUs

 Nov. 10, 2021

Here is the article.

AMD intros 3rd-gen Epyc server CPUs using 3D V-Cache and up to 768MB of L3 cache

AMD's Milan-X CPUs are drop-in compatible with a BIOS update


By  

GTE, RIG oil stock: My study | energy reality | https://financialpost.com/

Eric Nuttall: There's a massive chasm between government policy and our energy reality

Eric Nuttall: What do these energy realities mean for energy stocks?

It is epically frustrating that in Canada, a country blessed with some of the most abundant energy resources in the world, the majority of the population suffers from profound energy ignorance: the lack of knowledge of how hydrocarbons are used, how critical they are to our daily lives, and the realistic timeline to replace them with a “renewable” alternative.

Right now, wherever you are, look around. Everything you see, from the computer or piece of paper that you are reading this column on, from to the desk that you sit at, to the plastic lining in the coffee cup in front of you, all are either made of, or required the use of, hydrocarbons.

Without oil and natural gas, we would literally be back in the Stone Age, experiencing a fraction of our current standard of living. So how did we get here, where the average Canadian thinks the end of oil is at hand, politicians contemplate the necessity of limiting production growth, and where we have lost sight of how blessed we are as a nation to be gifted with such valuable energy resources produced in one of the most ethically and cleanest manners anywhere in the world?

Let’s start at the beginning. How exactly is oil, the largest commodity in the world used, and what are its potential replacements?

Every single day, the world consumes about 100 million barrels and demand is now back to pre-COVID levels despite jet fuel usage (8 per cent of total use) remaining weak due to lingering inconveniences such as quarantines and expensive testing requirements. According to the BP Statistical Review, of the 100 million barrels per day of daily usage, 60 million are for transportation (27 million by cars, 18 million in heavy hauling trucks, 8 million in planes, and the rest in ships and public transit). Just how big of a feat will it be to convert a staggering 1.45 billion vehicles, 29,000 aircraft, and 54,000 ships to renewable fuel sources and what is the timeline for them to reach critical scale?

For cars, the obvious alternative is electrification and in many countries, all new car sales must be emissions free (from the tailpipe, not necessarily the power source) by 2035. Electric car sales were approximately 5 million units in 2020 and while this number will steadily increase as more automakers develop new models at varying price points, how long will it take not just for electric car sales to gain meaningful share of news sales but to displace the 1.4 billion existing install base which will continue to grow for years to come (here’s a hint…the Energy Information Administration recently projected that the U.S. internal combustion car fleet won’t peak until 2038)?

What of the need to materially increase power generation capabilities to meet this new source of demand (the U.S. would have to roughly double its total energy power), while some simultaneously seek to entirely decarbonize their existing power grid by 2035? How will this massive undertaking occur when many basic raw elements, which are absolutely essential for increasing power generation and building car batteries, are entering into structural deficits such as copper, estimated by Royal Bank of Canada to be at a 32 per cent deficit by 2030, or nickel supply estimated by Rapidan to fall short of demand by 2024.

There is a massive chasm between well-intentioned government policies and our energy reality and yet eventually those two dynamics must eventually converge.

What of industry’s ability to produce enough hydrogen to displace the diesel used in heavy hauling trucks or produce renewable jet fuel, which is only now in the pilot project stage? Ignoring the massive financial requirement measured in many billions of dollars, it is estimated to take at least 20 years to reach any semblance of critical mass.

With all of that said, believe it or not, replacing the 60 million barrels per day of oil used in transportation with electrification, hydrogen, and renewable jet fuel is the easy part, relatively speaking. What of the other 40 million barrels of daily consumption that is not used for transportation, such as petrochemicals, plastics, cement, lubricants, rubber, agriculture, makeup, medicine, and over 2,000 other usages? What drives this demand growth and are there substitutions for the hydrocarbon based products that we use and rely on every day?

The world’s population today is approximately 7.7 billion and according to the United Nations is set to grow by 2 billion people by 2050, the time when the world is meant to reach “net zero” emissions status. With developed countries such as Canada, the United States, and Japan reaching peak population, the addition of 2 billion people will largely occur in Africa and Asia, areas of the world where living standards today are low yet are set to rise and this has a direct read through to how much hydrocarbons they will consume.

The average person in the world consumes only five barrels of oil per year yet in the United States, where higher living standards translates to higher hydrocarbon demand, that number is roughly 21. Thus, as the world’s population grows by 26 per cent and with it average hydrocarbon usage per person, how is it fathomable that the global demand for such things as plastics, fertilizer, mined metals for electronics, and specialty chemicals will fall?

What do these energy realities mean for energy stocks?

Given the average energy company I follow could become debt free and buy back all of their shares outstanding with only 3.3 years of free cash flow at the current oil price, the market is clearly placing a massive and unwarranted valuation discount on them due to “stranded asset” risk. In other words, if most people believe the end of oil is near why place any value on barrels held in reserve ten to fifteen years from now? To me, that is the generational opportunity.

Even under the most penalizing scenario in which all announced government decarbonization initiatives are met, Sanford C. Bernstein & Co. LLC forecasts that oil demand will continue to grow until 2034 at which point oil demand will only slowly begin to decline.

Yet, the fear of peak demand is leading to the reality of peak supply and if oil companies are not willing to sufficiently invest today in order to maintain productive capacity, what will be their willingness a decade from now when the visibility for peak oil demand becomes increasingly clear?

Given that the price of any good is impacted not just by demand but by supply, this dynamic in my view will continue to put upwards pressure on the oil price even with falling demand.

As the clouds of energy ignorance begin to part, it should be increasingly clear: the demand for oil will continue to grow and likely only peaking sometime in the 2030s, yet we will all be using oil for the rest of our lifetimes. With energy stocks trading at their lowest valuation levels in history and literally zero value being placed on long-dated reserves the opportunity lies in buying value for nothing and waiting for the inevitable rerating. Given a very strong macro backdrop for oil and meaningful shareholder returns being recently announced by companies, the wait will no longer be a long one.

Eric Nuttall is a partner and senior portfolio manager with Ninepoint Partners LP.


姚期智2021年京都奖演讲全文:计算机科学之旅

Nov. 10, 2021

Here is the article.

每年,该奖项会颁发给为科学进步、文明发展以及人类精神的丰富和提升做出卓越贡献的个人。京都奖分为先进技术、基础科学、艺术与哲学三个类别,每个类别包括四个领域,共计 12 个领域。三个类别各颁发一个奖项,每个类别的奖金为 1 亿日元。

今年早些时候,清华大学交叉信息研究院院长姚期智获得了 2021 年京都奖,以表彰他对计算和通信新理论及其安全基础理论做出了开创性贡献。

姚期智开创了计算机科学的新趋势,通过建立具有创新性的计算和通信基础理论,为各个领域的前沿研究做出了巨大贡献,特别是在安全、安全计算和量子计算方面。他的成就持续影响着当前的现实世界问题,例如安全、安全计算和大数据处理。

姚期智和其他两位 2021 年京都奖得主在 2021 年京都奖特别网站上都有相关介绍,包括作品、简介和三分钟的介绍视频。今年的京都奖还授予了洛克菲勒大学生物化学和分子生物学领域的教授 Robert G. Roeder(基础科学类);巴黎政治学院名誉教授 Bruno Latou(艺术与哲学类)。

今天, 2021 年京都奖官网发布了姚期智为本次奖项进行的英文报告——“计算机科学之旅”。出于科学传播的目的,【学术头条】将该报告整理成文,以飨读者。

在这份报告中,姚期智分享了他年轻时和学术生活中的故事,以及他从物理学和计算机科学的成就中所获得的见解。

回顾了自己的研究生涯,他说道:
“在科学中,范式是寻求真理。在这个过程中,我们有时会发现可以升华人类精神的样式和美感。它也追求创新以改善人类境况,让我们为未来人类需要面对的挑战做好准备。”
以下为报告全文:

女士们,先生们,我很高兴来到这里。首先我要说,获得京都奖是一种莫大的荣幸。了解了历届获奖者和他们的辉煌成就后,我为自己被认为值得与他们齐名而深感谦卑,也很高兴和荣幸在这里发言。

今天,我想谈谈我的成长经历,如何进入计算机科学领域,以及一路走来的旅程。

更详细地,我将从我的背景开始,讲一讲我小时候对物理学的痴迷,这后来促成了我选择了第一个职业,然后,我会讲到我是如何偶然转换领域并成为一名计算机科学家的。之后我会简单介绍我的研究工作、我所思考的问题以及它们为什么有趣。结束之前,我还要向几位对我的生活和工作产生重大影响的人致敬。

1946 年,我出生在中国上海。不久后,我的家人搬到了香港,然后又搬到了台湾。我在一个幸福的中产阶级家庭长大,有慈爱的双亲和两个非常亲密的兄弟/姐妹 。

我从小深受中国传统价值观熏陶,特别是对文化和学习非常重视。令我和我父母欣慰的是,我是一名优秀的学生,学生时期一直是名列前茅。

我记得我小时候喜欢数学、科学和历史。

对历史人物着迷,是因为他们表现出不同寻常的勇敢和智慧。像伽利略和牛顿这样的科学家,他们也是我心目中的英雄,因为他们的才华以及为自己的信仰挺身而出的勇气,让我大为震撼。我梦想有一天自己也会成为这样的人。

高中三年级,我偶然发现了亚瑟·爱丁顿爵士关于相对论的笔记副本,其中给出了相对论最生动、最简单的推导。

大致如下:实验中,我们已经知道光具有恒定的速度。从这一事实,我们可以巧妙地推导出我们熟悉的时间概念不可能是一个绝对普遍的概念。而长期以来,这一点是每个人都认为理所当然的事情。

这个论点给我留下了深刻的印象。我发现,物理学可以像侦探故事一样吸引人,而且比“福尔摩斯”中任何聪明的情节都更具想象力。这令我深受鼓舞。于是在1963年,我在大学选择了主修物理。

不久之后,理查德·费曼的物理学讲义发表了。

传说加州理工学院想从根本上重组他们的物理学大一课程,费曼同意这样做,条件是他只教一次。由此诞生了传奇的三卷本物理学讲义《费曼物理学讲义》。

这个系列讲义让我大开眼界。难以解释的高级概念,结果其证明只用初级数学就可以解释和推导出来。这真是令人印象深刻,让我看到了物理学的深度和美妙。

事实上,这是我第一次觉得自己真正理解了量子力学的原理。30 年后,当我开始从事量子计算领域的工作时,费曼对量子现象的解释在我看来仍然是最有启发性和最有用的解释。

这让我坚定下来,决定在大学毕业后继续在物理学深造。1967年,我大学毕业后服了一年兵役,之后前往哈佛大学攻读物理学研究生。1972 年,我在 Sheldon Glashow 教授的指导下获得了物理学博士学位。

最终我成为了真正的物理学家,但这并没有持续多久。1973 年,当时我在麻省理工学院攻读博士学位的妻子 Frances 向我介绍了“算法”。

算法这个词今天已频繁出现在日常生活中,但在当时,对大多数人来说,这是一个非常陌生的词汇。当时,我接触到高德纳教授编写的《计算机程序设计艺术》的早期草稿。这是一本很有名的关于算法的书,一个多么了不起的杰作,它介绍了一门引人入胜的新科学。
阅读后,我开始不断思考书中提出的研究问题,深陷其中而无法自拔,以至于我很快就辞去了物理学博士后的工作,转而全职攻读计算机科学研究生。

我记得我母亲当时很担心我,因为我似乎放弃了这么多年的物理工作,但我的妻子非常支持我。所以我成为了伊利诺伊大学的计算机科学研究生。非常感谢 CL Liu 教授愿意接受我。

接下来,我将讲述我的工作。最初,我专注于解决算法中现有的开放问题,例如最小生成树、B 树等。但毕业后不久,我开始对开发计算机科学的新框架和新理论产生兴趣。

几十年来,我有机会在几所一流大学工作。我在伯克利、斯坦福度过了 10 年,随后在普林斯顿度过了 18 年。2004 年,我加入了清华大学,直至今日。

在每个时期,我都在做一些不同的事情。很有趣的是,我在不同时期关注的主题,它们与时代的变化和计算机科学作为一门学科的发展,以及身处的大学环境都有很大关系。

接下来,我想要介绍三个主题,极大极小算法 (min max complexity),通信复杂度 (communication complexity),以及密码学和 MPC。

我发现做研究最好的方法是提出深刻、大胆和关键性的问题。如果你能提出好问题,那么就一定会做好研究,得出对学术界来说实用且有重大意义的结论。现在我将对每个主题的主要问题及其重要性进行讨论。
第一个是 1977 年提出的极大极小算法问题。它在我心中有很特殊的位置,因为这是我第一次提出了自己的研究问题,并找到了很好的解决方法。我们知道,算法本质上和食谱很像。例如在烹饪中,食谱会告诉你每步的步骤,例如放 3 盎司盐或几克肉。

20 世纪 70 年代中期,一种新的算法引起了人们的注意,即“随机化算法”(Randomized algorithm)。这种新算法结合了随机移动 (stochastic moves)。如果用烹饪来比喻的话就是,不明确告诉你有放两勺盐的步骤,而是让你用扔硬币决定是放两勺盐,还是放一杯红酒。

因此,对于传统的思维方式来说,这看起来是一种疯狂的做事方式。但在 20世纪70年代,人们已经证明以这种方式执行算法是有优势的,在某些情况下,它们会产生一些令人惊叹的结果。但人们还无法理解这些算法的局限性。

因此,这让我产生了一个问题。到底哪算法个更好?是当时刚刚提出的随机化方法,还是用传统的方法观察数据分布,并在执行过程中调整呢?

一旦用这种方式提出了这个问题,那么就出现了一种令人惊喜的联系,让人们可以对随机化算法有了很多的了解。

当把随机化算法与传统分布方法进行比较时,可以将其视为随机化算法和数据之间的博弈。算法(可以根据数据)选择如何随机移动,而数据(对手)可以选择分布方式,从而使算法的运行变得更加困难。在博弈论极大极小原理(冯·纽曼) 的作用下下这两种方法恰好达到了它们的极限。这个联系给出了我们想要证明的定理,也就是说事实上这两种方法是相同的。这为理解随机化算法提供了新途径。在现在,这种在当时还算新颖的算法已经成为许多密码技术和人工智能算法的默认模式。
人们想了解随机化算法的局限性是有原因的。因此,在 40 多年的时间里,我发现的算法仍然被许多研究人员用来来解决他们的问题。第二个主题是我在 1979 年提出的通信复杂性。

让我先解释一下这个数学问题,爱丽丝和鲍勃是两个在不同地点的人,他们各自持有一条 n 个比特的数据,比如 x 和 y。我们想要解决的问题是,假设它们想要联合计算某个量 f,它们之间需要通信多少比特,这就是这个函数的通信复杂度。

当然,这取决于你在计算什么函数,例如,要计算这两个整数的和是奇数还是偶数只需要两个比特的通信。每个人只需告诉对方它是偶数还是奇数,然后他们就可以知道答案了。

另一方面,如果你想计算 x 是否大于 y,那么它将需要 n 比特。你需要把整个字符串从一个人发送给另一个人才能解决这个问题。更深一层的是,你必须意识到并证明,没有比这种方式来解决这个问题更好的方法了。一般来说,这是一个相当困难的问题。如果我给你一个关于F的计算复杂性,那需要相当深入的数学分析才能完成。

考虑通信复杂度的原因是,计算模式在 20 世纪 70 年代末发生了很明显的变化。从之前大家都熟悉的大型计算机,逐渐转向我们现在熟悉的计算机网络。人们对以分布式方式解决问题感兴趣,许多人愿意协作解决问题。

因此,这意味着我们必须把过去的计算模型调整为网络模型。在这个新的世界里,通信成本通常是很高的,因为我们必须移动数据。因此,我刚刚向你们的介绍的通信复杂度的概念就是为了模拟和反映这种变化。

自从该模型被提出和分析以来,通信复杂性在从芯片设计到数据流的各个领域都得到了广泛的应用。我要讨论的最后一个话题是关于密码学和 MPC。

1982 年,我写了三篇论文,这些论文对现代密码学做出了重大贡献。这三篇论文涉及 Dolev-Yao 威胁模型、伪随机数生成算法(pseudo random number generation)和安全多方计算(MPC)。今天我只谈最后一个问题。

MPC 是一个加密概念,使我们可以对加密数据进行计算。如果您使用 MPC,就有可能让多个数据库在不泄露它们自己的数据的情况下进行联合计算。

也就是说,我们可以在看不到数据的情况下共享数据。让我用一个例子来解释一下这一点。我将引用在论文中提到的著名的亿万富翁的例子。

两个百万富翁,爱丽丝和鲍勃,他们希望在不透露任何数据信息的情况下知道谁更有钱。所以爱丽丝有 X 百万,鲍勃有 Y 百万。所以数学问题是,他们想要彼此交流来知道 X 是否小于 Y。问题是,是否有可能进行一次对话,让双方在不知道对方数据的情况下又知道谁更富有呢?

直觉上来说你会认为这是不可能的。我怎样才能在不透露任何一方任何信息的情况下找出谁更富有呢?如果你想几分钟你就会意识到,如果采用 1982 年的信息安全定义,也就是香农的信息论( Shannon's information theory),那确实是不可能的,你可以证明在那个模型下是不可能的。

但我认为,需求是所有发明之母。如果真的有需要的话你肯定会想尽一切办法。所以,如果你跳出框框去思考,事实证明这是可能的。说到跳出框框,我们的意思是需要丢弃香农在这种情况下规定的非常死板的条条框框,然后把艾伦·图灵纳入其中,我不会对此说太多。但事实证明,如果你把安全定义放宽一些,让它变成一个务实且足够好的标准,那么这个问题事实上是有解的。具体地说,我用“乱码电路” (garble circuit)实现了解决方案。

在过去近 40 年的发展中,它在硬件和算法方面取得了进步,现在几乎是可行的。而这方面的研究工作也很多,准备在金融科技、数据交易、药物研发等方面开展工作。

目前我还有一些其他的研究课题,就不一一详述了。我的课题包括:革命性、有望实现指数级增长的量子计算技术;可以用博弈论来解决经济问题的拍卖理论;人工智能,这项技术见证了 AlphaGo 等机器学习算法取得的令人难以置信的壮举,但成功的原因仍然是个谜。

所有这些都是非常有趣的新领域,而且还在持续发展中。如你所见,我研究过很多不同的课题。这些丰富多彩的课题,实际上不仅反映了我个人的喜好,也反映了半个世纪以来信息科学的蓬勃发展,以及我们今天所看到的日益增长的跨学科联系。

最后,我想对我人生中遇到的人说几句话。

在这些年里,作为一名计算机科学家,我有幸遇到了许多才华横溢的人。我非常幸运地遇到了两位给我巨大灵感的导师,Glashow 教授和 Knuth 教授 。

Glashow 教授是我在哈佛大学的物理学博士导师。他是最先预言存在 Charm Quarks 这种粒子的人之一,也是这种粒子最积极的倡导者。

我从 Glashow 教授那里学到,在科学上你必须大胆,你必须坚持不懈地坚持你的信仰。

我从他身上学到的另一件事是,数学和物理是不同的。对于物理学家来说,最重要的是能够找出物理现实的真相,而不是坚持精确的数学论证。我认为这种务实精神对我以后的研究有很大帮助。

还有一件事是我从 Glashow 教授那里学到的:生活应该是有趣的。

1971 年春天,作为一个年轻的学生,我跟随他去法国马赛的 CNRS 休假。这是一个多么神奇和迷人的城市,那也是我第一次来欧洲。那年夏天的晚些时候,他带我去了意大利西西里的一个暑期学校。

这是一次非常美妙的经历。Gladshow 教授给我上的这一课让我明白,生活的乐趣和对知识的追求可以兼而有之。
现在,我想提一下 Knuth 教授。正如我之前所提到的,当我读到《计算机编程的艺术》时,它几乎改变了我的生活。在这本著作中,他确实开创了一个新的研究领域,也激励了一代又一代新的计算机科学家。

例如,通过阅读他的书,我开启了自己的计算机科学生涯,并解决了一些他在书中所阐述的问题。

后来,我有幸成为他在斯坦福的同事。众所周知,除了数学和计算机科学之外,Knuth 教授在许多方面都很在行。他是一位才华横溢的管风琴演奏家。他还是一位作曲家、小说家等。

所以他多才多艺,且也真诚大方。他总是在别人身上看到好的一面。
总而言之,虽然经历了一些曲折,但我在计算机科学领域还是度过了一段美好的旅程。我发现,一开始就走错方向可能并不是什么坏事。

事实上,早期的物理训练至少在两个方面对我有很大帮助。

首先,我了解到好的理论在物理学中是什么样子的,比如经典的相对论和量子力学。在之后提出计算机科学的理论时,这对我有很大的帮助。

我从物理学中受益的第二件事是它的务实精神。它教会我解决手头的特定问题。不管用什么方法,你都应该根据情况使用、学习或发明解决问题的方法,最终目标是解决问题。

科学是对真理的追求。在这个过程中,我们会发现科学规律和科学的美,提升人类共同的精神。它还带来了创新,可以改善人类的现状,为未来所面临的挑战做好准备。

我完全同意稻盛和夫基金会(Inamori Foundation)的愿景,即科学和人文应该为人类的进步而共同努力。我很荣幸能获得京都奖,也很荣幸能做这次演讲,与听众分享我的经历。非常感谢。

报告完整视频见 2021 年京都奖官网:
https://www.kyotoprize.org/2021/andrew_chi-chih_yao/