The author recounts their visit to the National Museum of the U.S. Air Force in Dayton, Ohio, specifically to see the XB-70 Valkyrie. They were deeply impressed by the sheer size and unique design of this experimental supersonic bomber, describing its presence as awe-inspiring and otherworldly. The post focuses on the aircraft's visual impact, highlighting features like the drooping wingtips and massive size, alongside numerous high-quality photographs showcasing the plane from various angles. The author emphasizes the privilege of witnessing such a rare and significant piece of aviation history, capturing their personal sense of wonder and the enduring legacy of the XB-70.
This 2019 EEG study investigated the neural correlates of four different jhāna meditative states in experienced Buddhist practitioners. Researchers found distinct EEG signatures for each jhāna, characterized by progressive shifts in brainwave activity. Specifically, higher jhānas were associated with decreased alpha and increased theta power, indicating a transition from relaxed awareness to deeper meditative absorption. Furthermore, increased gamma power during certain jhānas suggested heightened sensory processing and focused attention. These findings provide neurophysiological evidence for the distinct stages of jhāna meditation and support the subjective reports of practitioners regarding their unique qualities.
Hacker News users discussed the study's methodology and its implications. Several commenters questioned the small sample size and the potential for bias, given the meditators' experience levels. Some expressed skepticism about the EEG findings and their connection to subjective experiences. Others found the study's exploration of jhana states interesting, with some sharing their own meditation experiences and interpretations of the research. A few users also discussed the challenges of studying subjective states scientifically and the potential benefits of further research in this area. The thread also touched on related topics like the placebo effect and the nature of consciousness.
This 2019 War on the Rocks article argues that while obedience is generally essential in the military, blind obedience can be detrimental. It emphasizes the importance of fostering a culture where subordinates possess the judgment and moral courage to disobey unlawful, unethical, or strategically unsound orders. The piece uses historical examples, such as the My Lai Massacre, to illustrate the dangers of unquestioning obedience and highlights the responsibility of leaders to create an environment that encourages dissent when necessary. Ultimately, it advocates for a balance between obedience and independent, critical thinking within the military chain of command to ensure ethical conduct and mission success.
HN users discuss the complexities of disobedience in the military, emphasizing the difficulty of discerning lawful from unlawful orders in real-time, high-stress situations. Some highlight the importance of clear, pre-established guidelines and training to equip soldiers for these scenarios. Others point out the potential consequences of disobedience, even when justified, and the burden of proof placed on the individual. The inherent power imbalance in the military structure and the potential for abuse are also touched upon, with one commenter suggesting the necessity of strong legal protections for whistleblowers and those who refuse unlawful orders. Several commenters offer personal anecdotes or historical examples to illustrate the nuances and challenges involved in military disobedience. Finally, some question the practicality of the proposed framework in the linked article, arguing that it doesn't adequately address the pressure and fear often present in combat situations.
The "Butter Thesis" argues that seemingly insignificant details in software, like the specific shade of yellow used for a highlight color ("butter"), can have a surprisingly large impact on user perception and adoption. While technical improvements are important, these subtle aesthetic choices, often overlooked, contribute significantly to a product's "feel" and can ultimately determine its success or failure. This "feel," difficult to quantify or articulate, stems from the accumulation of these small details and creates a holistic user experience that transcends mere functionality. Investing time and effort in refining these nuances, though not always measurable in traditional metrics, can be crucial for creating a truly enjoyable and successful product.
HN commenters largely agree with the author's premise that side projects are valuable for learning and skill development. Several point out the importance of finishing projects, even small ones, to gain a sense of accomplishment and build a portfolio. Some disagree with the "butter" analogy, suggesting alternatives like "sharpening the saw" or simply "practice." A few commenters caution against spreading oneself too thin across too many side projects, recommending focused effort on a few key areas. Others emphasize the importance of intrinsic motivation and enjoying the process. The value of side projects in career advancement is also discussed, with some suggesting they can be more impactful than formal education or certifications.
"An Infinitely Large Napkin" introduces a novel approach to digital note-taking using a zoomable, infinite canvas. It proposes a system built upon a quadtree data structure, allowing for efficient storage and rendering of diverse content like text, images, and handwritten notes at any scale. The document outlines the technical details of this approach, including data representation, zooming and panning functionalities, and potential features like collaborative editing and LaTeX integration. It envisions a powerful tool for brainstorming, diagramming, and knowledge management, unconstrained by the limitations of traditional paper or fixed-size digital documents.
Hacker News users discuss the "infinite napkin" concept with a mix of amusement and skepticism. Some appreciate its novelty and the potential for collaborative brainstorming, while others question its practicality and the limitations imposed by the fixed grid size. Several commenters mention existing tools like Miro and Mural as superior alternatives, offering more flexibility and features. The discussion also touches on the technical aspects of implementing such a system, with some pondering the challenges of efficient rendering and storage for an infinitely expanding canvas. A few express interest in the underlying algorithm and the possibility of exploring different geometries beyond the presented grid. Overall, the reception is polite but lukewarm, acknowledging the theoretical appeal of the infinite napkin while remaining unconvinced of its real-world usefulness.
ICANN's blog post details the transition from the legacy WHOIS protocol to the Registration Data Access Protocol (RDAP). RDAP offers several advantages over WHOIS, including standardized data formats, internationalized data, extensibility, and improved data access control through different access levels. This transition is necessary for WHOIS to comply with data privacy regulations like GDPR. ICANN encourages everyone using WHOIS to transition to RDAP and provides resources to aid in this process. The blog post highlights the key differences between the two protocols and reassures users that RDAP offers a more robust and secure method for accessing registration data.
Several Hacker News commenters discuss the shift from WHOIS to RDAP. Some express frustration with the complexity and inconsistency of RDAP implementations, noting varying data formats and access methods across different registries. One commenter points out the lack of a simple, unified tool for RDAP lookups compared to WHOIS. Others highlight RDAP's benefits, such as improved data accuracy, internationalization support, and standardized access controls, suggesting the transition is ultimately positive but messy in practice. The thread also touches upon the privacy implications of both systems and the challenges of balancing data accessibility with protecting personal information. Some users mention specific RDAP clients they find useful, while others express skepticism about the overall value proposition of the new protocol given its added complexity.
Latacora's blog post "How (not) to sign a JSON object" cautions against signing JSON by stringifying it before applying a signature. This approach is vulnerable to attacks that modify whitespace or key ordering, which changes the string representation without altering the JSON's semantic meaning. The correct method involves canonicalizing the JSON object first – transforming it into a standardized, consistent byte representation – before signing. This ensures the signature validates only identical JSON objects, regardless of superficial formatting differences. The post uses examples to demonstrate the vulnerabilities of naive stringification and advocates using established JSON Canonicalization Schemes (JCS) for robust and secure signing.
HN commenters largely agree with the author's points about the complexities and pitfalls of signing JSON objects. Several highlighted the importance of canonicalization before signing, with some mentioning specific libraries like JWS and json-canonicalize to ensure consistent formatting. The discussion also touches upon alternatives like JWT (JSON Web Tokens) and COSE (CBOR Object Signing and Encryption) as potentially better solutions, particularly JWT for its ease of use in web contexts. Some commenters delve into the nuances of JSON's flexibility, which can make secure signing difficult, such as varying key order and whitespace handling. A few also caution against rolling your own cryptographic solutions and advocate for using established libraries where possible.
"Trails of Wind" is a generative art project exploring the visualization of wind currents. Using weather data, the artwork dynamically renders swirling lines that represent the movement and direction of wind across a global map. The piece allows viewers to observe complex patterns and the interconnectedness of global weather systems, offering an aesthetic interpretation of otherwise invisible natural forces. The project emphasizes the ever-shifting nature of wind, resulting in a constantly evolving artwork.
HN users largely praised the visual aesthetic and interactive elements of "Trails of Wind," describing it as mesmerizing, beautiful, and relaxing. Some appreciated the technical aspect, noting the clever use of WebGL and shaders. Several commenters pointed out the similarity to the older "wind map" visualizations, while others drew comparisons to other flow visualizations and generative art pieces. A few users wished for additional features like zooming, different data sources, or adjustable parameters. One commenter raised the concern about the project's longevity and the potential for the underlying data source to disappear.
An analysis of Product Hunt launches from 2014 to 2021 revealed interesting trends in product naming and descriptions. Shorter names, especially single-word names, became increasingly popular. Product descriptions shifted from technical details to focusing on benefits and value propositions. The analysis also highlighted the prevalence of trendy keywords like "AI," "Web3," and "No-Code," reflecting evolving technological landscapes. Overall, the data suggests a move towards simpler, more user-centric communication in product marketing on Product Hunt over the years.
HN commenters largely discussed the methodology and conclusions of the analysis. Several pointed out flaws, such as the author's apparent misunderstanding of "nihilism" and the oversimplification of trends. Some suggested alternative explanations for the perceived decline in "gamer" products, like market saturation and the rise of mobile gaming. Others questioned the value of Product Hunt as a representative sample of the broader tech landscape. A few commenters appreciated the data visualization and the attempt to analyze trends, even while criticizing the interpretation. The overall sentiment leans towards skepticism of the author's conclusions, with many finding the analysis superficial.
The blog post argues that C's insistence on abstracting away hardware details makes it poorly suited for effectively leveraging SIMD instructions. While extensions like intrinsics exist, they're cumbersome, non-portable, and break C's abstraction model. The author contends that higher-level languages, potentially with compiler support for automatic vectorization, or even assembly language for critical sections, would be more appropriate for SIMD programming due to the inherent need for data layout awareness and explicit control over vector operations. Essentially, C's strengths become weaknesses when dealing with SIMD, hindering performance and programmer productivity.
Hacker News users discussed the challenges of using SIMD effectively in C. Several commenters agreed with the author's point about the difficulty of expressing SIMD operations elegantly in C and how it often leads to unmaintainable code. Some suggested alternative approaches, like using higher-level languages or libraries that provide better abstractions, such as ISPC. Others pointed out the importance of compiler optimizations and using intrinsics effectively to achieve optimal performance. One compelling comment highlighted that the issue isn't inherent to C itself, but rather the lack of suitable standard library support, suggesting that future additions to the standard library could mitigate these problems. Another commenter offered a counterpoint, arguing that C's low-level nature is exactly why it's suitable for SIMD, giving programmers fine-grained control over hardware resources.
This blog post explores creating spirograph-like patterns by simulating gravitational orbits of multiple bodies. Instead of gears, the author uses Newton's law of universal gravitation and numerical integration to calculate the paths of planets orbiting one or more stars. The resulting intricate designs are visualized, and the post delves into the math and code behind the simulation, covering topics such as velocity Verlet integration and adaptive time steps to handle close encounters between bodies. Ultimately, the author demonstrates how varying the initial conditions of the system, like the number of stars, their masses, and the planets' starting velocities, leads to a diverse range of mesmerizing orbital patterns.
HN users generally praised the Orbit Spirograph visualization and the clear explanations provided by Red Blob Games. Several commenters explored the mathematical underpinnings, discussing epitrochoids and hypotrochoids, and how the visualization relates to planetary motion. Some users shared related resources like a JavaScript implementation and a Geogebra applet for exploring similar patterns. The potential educational value of the interactive tool was also highlighted, with one commenter suggesting its use in explaining retrograde motion. A few commenters reminisced about physical spirograph toys, and one pointed out the connection to Lissajous curves.
Summary of Comments ( 117 )
https://news.ycombinator.com/item?id=43175315
HN commenters generally express awe at the XB-70's ambitious design and capabilities, with several noting its stunning appearance and sheer size. Some discuss the technical challenges overcome in its creation, like the unique compression lift generated by its wingtips and the complex fuel system needed for Mach 3 flight. Others lament the project's cancellation, viewing it as a missed opportunity for advancements in supersonic flight. A few commenters offer personal anecdotes about seeing the aircraft in person, highlighting the visceral impact of witnessing such a large and unusual plane. The impracticality of the XB-70 as a bomber due to advancements in surface-to-air missiles is also mentioned, along with its later contributions to supersonic research. A recurring theme is the romanticism surrounding the project, representing a bygone era of ambitious aerospace engineering.
The Hacker News post titled "The XB-70 (2019)" linking to an article about the XB-70 Valkyrie bomber on codex99.com has a moderate number of comments, sparking a discussion around the aircraft's history, capabilities, and legacy.
Several commenters discuss the tragic mid-air collision between the XB-70 and an F-104 chase plane in 1966. This incident, which resulted in the destruction of the F-104 and severe damage to the XB-70, is a pivotal point in the aircraft's history and is mentioned by multiple users. One commenter questions the physics behind the collision, prompting a detailed explanation from another user about the complex interaction of shockwaves and vortexes around supersonic aircraft, highlighting the dangers of close formation flying at such high speeds.
The XB-70's role as a strategic bomber during the Cold War and its eventual cancellation are also subjects of discussion. Commenters delve into the reasons behind the project's termination, including the rise of intercontinental ballistic missiles (ICBMs) and the increasing effectiveness of Soviet air defenses. The changing strategic landscape rendered the XB-70's mission profile increasingly vulnerable and ultimately led to the decision to halt its development.
Another thread focuses on the aircraft's impressive performance and technological advancements. Users marvel at its Mach 3 speed capability and the innovative design solutions required to overcome the challenges of high-speed flight, such as the use of stainless steel honeycomb panels and the ability to droop the wingtips. The XB-70's influence on later aircraft designs is also acknowledged.
Some commenters share personal anecdotes and memories related to the XB-70, including witnessing it in flight or visiting the surviving aircraft on display at the National Museum of the United States Air Force. These personal accounts add a human element to the discussion and underscore the lasting impression this iconic aircraft has made.
Finally, a few comments touch upon related topics, such as other experimental aircraft of the era and the broader context of the Cold War arms race. These comments broaden the scope of the conversation and provide further historical perspective.
Overall, the comments on the Hacker News post offer a mix of technical details, historical context, and personal reflections, painting a multifaceted picture of the XB-70 and its significance.