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A loosely sorted and lightly annotated catalogue of through the music posts on this blog.

Here’s a very cool theory paper I came across online. A theory of multihoming in rideshare competition. Bryan KA, Gans JS. *J Econ Manage Strat.*2019;28:89–96. https://doi.org/10.1111/jems.12306 It takes a messy, important, real-world phenomenon and find the minimal model that isolates the key force. Here’s my note on part of the paper: Disclaimer: all mistakes are mine. all rights belong to the author and publisher. Two firms $i \in \{1, 2\}$ sit at the two ends of a Hotelling segment $[0, \ell]$, where $\ell$ indexes demand density. Each firm chooses an idleness level $\delta_i \in [0, \ell/4)$ at convex cost $c(\delta_i)$ (with $c(0) = 0$, $c' > 0$, $c'' > 0$), then a price $p_i$. ...

It’s my favourite time of the year, and today is the Dragon Boat Festival (of 2026)! For this year I want to quote ‘同舟而济’: 夫吴人与越人相恶也，当其同舟而济，遇风，其相救也如左右手。《孙子兵法·九地》 Then the men of Wu and the men of Yüeh bear one another enmity; yet, should they cross the same river in one boat and be caught by a storm, they will fly to each other’s aid as the left hand succours the right. — Sun Tzu, The Art of War, Chapter XI (“The Nine Situations”) ...

There are probably more than a thousand articles teaching you what is attention. I’ve heard the talks quite some times too. Here’s by far the clearest article: 只用小学数学带你读懂AI封神论文《Attention Is All You Need》 (Only use primary school mathematics to take you to understand the AI Fengshen paper “Attention Is All You Need”) https://mp.weixin.qq.com/s/d7S3yE9IQWhjOMxzgG3I6Q Apple’s Safari built in web translator can even translate text in pictures — making cross-language information much easier to access. Nevertheless, you can always feed the og paper into AI to ask for a “primary school level” break down. Though I think this article is probably mostly written by human and of very high quality.

“Twilight zone” — the term is popularized by the show of the same name (1959) directed and produced by Rod Serling. When Rod Serling was asked how he came up with the title The Twilight Zone, he replied, ‘I thought I’d made it up, but I’ve heard since that there is an Air Force term relating to a moment when a plane is coming down on approach and it cannot see the horizon. It’s called the twilight zone…" — The Twilight Zone Archive ...

The Violin Sonata in E Major (Op. 18) is a cornerstone of the late-Romantic chamber repertoire, and it’s one of Richard Strauss’s most important early works. The 2nd mvt Improvisation: Andante cantabile is very lyrical, charming, matured and soothing. Who knows this guy is gonna write the crazy Salome 18 years later…

There are pieces that I know it before knowing its name. I have 4 recordings of Debussy’s Arabesque No. 1 in my Apple Music Library before I associate the waterfall-like appregios with the opus number. Arabesque originated from the Italian word arabesco, which literally translates to “in the Arabic style” — a highly intricate design or posture featuring flowing, interlaced, and curving lines. Debussy is more known for hamonies, but you also hear exquisite melody and lines too: ...

Article 35 DMA requires the Commission to submit an annual report on the implementation of the DMA and the progress made towards achieving its objectives. DMA Annual Report 2023 DMA Annual Report 2024 DMA Annual Report 2025 Here’s a short reading note that I outlined some economically interesting points: Disclaimer: I am not a lawyer, and this post is not legal advice. These are my personal reading notes on the EU Digital Markets Act — it’s for academic purposes only, and all mistakes are my own. Readers should consult the official legal text and, where necessary, a qualified lawyer for legal advice. Related: notes on The EU Digital Markets Act: A Report from a Panel of Economic Experts (February 9, 2021). Reading Notes of the EU’s Digital Market Act The gatekeeper are dynamically targeted In 2023, the Commission designated the first six gatekeepers: Alphabet, Amazon, Apple, ByteDance, Meta, and Microsoft, covering 22 core platform services. Samsung was not designated for its browser. Some services escaped designation after rebuttals, including Gmail, Outlook, iMessage, Bing, Edge, and Microsoft Advertising. In 2024, the map expanded. Booking was added for Booking.com, and Apple iPadOS was added as a core platform service. By the end of 2024, the regime covered seven gatekeepers and 24 core platform services. In 2025, the map became dynamic. Meta Marketplace was removed after Meta changed the service so that it no longer met the business-user threshold. By year-end, seven gatekeepers remained under supervision, covering 23 core platform services. Compliance moved inside the firm: gatekeepers now have to submit compliance reports, audited consumer-profiling reports, appoint independent compliance officers, attend workshops, answer information requests, and keep documents for enforcement review. In 2024, the Commission reviewed compliance reports, held workshops, met gatekeepers and third parties, and issued document-retention orders to six gatekeepers. ...

The Digital Markets Act (DMA) is the EU’s flagship regulatory framework for the competition and market-power problem of Big Tech platforms. The European Commission describes it as one of the first tools to comprehensively regulate the gatekeeper power of the largest digital companies. Disclaimer: I am not a lawyer, and this post is not legal advice. These are my personal reading notes on the EU Digital Markets Act — it’s for academic purposes only, and all mistakes are my own. Readers should consult the official legal text and, where necessary, a qualified lawyer for legal advice. Some related regulations are the Digital Services Act (DSA), GDPR, general EU competition acts, AI acts etc. Related: notes on The EU Digital Markets Act: A Report from a Panel of Economic Experts (February 9, 2021). TL;DR: The EU Digital Markets Act is an ex ante regulatory regime for large digital platforms that act as unavoidable gateways between businesses and users. ...

The new ballet is emotionally direct, superbly choreographed, and beautifully staged. It’s a full reinvention — new score and all — yet the story and its spirit stay faithful to Pushkin. Rating: ⭐️⭐️⭐️⭐️⭐️⭐️ — the extra ⭐️ for a modern recreation of a classic that doesn’t fall apart just because the director wanted to flash some avant-garde nonsense. ...