The hottest Physics Substack posts right now

And their main takeaways
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But good sir, what is electricity?

lcamtuf’s thing • 18977 implied HN points • 23 Feb 25
🔬 Science Electricity Physics Chemistry Electronics Materials
  1. Electricity is about how electrons interact with atoms. Electrons can move from one place to another, creating electric current in conductive materials like metals.
  2. Conductors, like metals, allow electrons to flow freely, while insulators hold onto their electrons tightly. This difference determines how well materials conduct electricity.
  3. The movement of electrons in a wire is what allows us to use electricity for various tasks. It can be quick, but individual electrons move slowly compared to the speed at which electrical signals travel.

Reading List 02/08/2025

Construction Physics • 7933 implied HN points • 08 Feb 25
🔬 Science Physics Engineering Technology Environment Health
  1. Ship-mounted lasers are being developed by the military to counter drone threats. These directed energy weapons may become crucial as drones are more widely used in conflicts.
  2. Santorini is experiencing a series of small earthquakes, leading to most residents evacuating. Authorities are on alert as they prepare for the possibility of a stronger quake.
  3. Ford is facing significant losses in its electric vehicle division as high costs for development and low sales numbers are piling up. The company estimates it could lose up to $5.5 billion this year on EVs.

The Higgs Discovery Did Not Take Place

arg min • 1071 implied HN points • 22 Oct 24
🔬 Science Physics Statistics Quantum Mechanics Scientific Method
  1. The Higgs boson was theoretically discovered, but many people argue that this claim isn't solid due to complex statistical methods used in the research. It's not just about finding a particle; it's heavily based on probabilities.
  2. A lot of the processes in particle physics rely on trust within scientific communities and committees. They decide what counts as 'discovery' often through agreed conventions rather than direct proof.
  3. Questions about the Higgs boson reflect broader concerns in science regarding accountability. It shows that scientific findings often come down to people, their processes, and their decisions rather than just raw data.

What's the deal with magnetic fields?

lcamtuf’s thing • 4897 implied HN points • 04 Feb 25
🔬 Science Physics Electromagnetism Electricity Materials
  1. Electric fields are easy to understand because they involve the forces between charged particles, like how magnets attract or repel each other. This basic concept helps explain how electricity works in circuits.
  2. Magnetic fields can be confusing because they seem separate from electric fields, but they are connected through the concept of relativity. When things move, their distances and timings can change, affecting how we see electric and magnetic effects.
  3. Understanding that moving charges create magnetic fields helps simplify the whole idea. It's all about how motion changes our perspective on distance and forces between charges.

Toward a Transformative Hermeneutics of Standard Model Physics

arg min • 456 implied HN points • 25 Oct 24
🔬 Science Physics Statistics Philosophy Research Collaboration
  1. The Higgs discovery shows how science relies on consensus rather than just statistics. It's all about how many scientists agree on something, and that's what really gives it weight.
  2. Complex governance structures are necessary in big science projects. These systems help teams work together and make important decisions about groundbreaking discoveries.
  3. Sometimes, playful writing can lead to misunderstandings. It's important to find the right balance between being engaging and being precise when discussing complex topics.
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Weekly Dose of Optimism #131

Not Boring by Packy McCormick • 113 implied HN points • 14 Feb 25
🔬 Science Physics Health Technology Cancer Astronomy
  1. A deep-sea telescope called KM3NeT has detected the highest-energy neutrino ever recorded, which could help scientists learn more about extreme cosmic events like black holes.
  2. A new blood test named PAC-MANN can detect pancreatic cancer early and accurately, potentially improving survival rates for patients.
  3. Anduril is taking over a big military project to develop augmented reality headsets for the U.S. Army, which could enhance soldiers' performance on the battlefield.

Great scientists follow intuition and beauty, not rationality

The Intrinsic Perspective • 33817 implied HN points • 30 Dec 24
🔬 Science Physics Mathematics Philosophy History Psychology
  1. Great scientists often rely on their gut feelings and a sense of beauty rather than just cold hard logic. This mix of intuition leads to important discoveries.
  2. Famous scientists aren't just rational thinkers; they have quirky beliefs and passions that drive their creativity. This uniqueness helps them come up with groundbreaking ideas.
  3. There's a complex balance between formal science and the imaginative, intuitive side. Embracing both can push the boundaries of what we understand about the universe.

AI, Cybernetics, and Complexity: unpacking the 2024 Nobel Prizes

Complexity Thoughts • 319 implied HN points • 14 Oct 24
🔬 Science Complexity Cybernetics Artificial Intelligence Physics Biology
  1. The 2024 Nobel Prizes recognized important advances in AI, but these discoveries are also deeply connected to complex systems. This shows that complexity science is becoming a more accepted area in high-level research.
  2. Understanding complex systems requires looking beyond traditional boundaries of science. The future of breakthroughs may rely on merging different scientific fields and using interdisciplinary approaches.
  3. Success in tackling complex challenges, like climate change and health issues, will need both detailed analysis of parts and a broader view of systems. Researchers must balance reductionist methods with insights from complexity science.

Sora still appears to have trouble with physics

Marcus on AI • 3636 implied HN points • 10 Dec 24
🕹 Technology AI Computer Science Data Physics Innovation
  1. Sora struggles to understand basic physics. It doesn't know how objects should behave in space or time.
  2. Past warnings about Sora's physics issues still hold true. Even with more data, it seems these problems won't go away.
  3. Investing a lot of money into Sora hasn't fixed its understanding of physics. The approach we're using to teach it seems to be failing.

The marvelous disappearing capacitor

lcamtuf’s thing • 4285 implied HN points • 07 Dec 24
🕹 Technology Electronics Engineering Physics Signal Processing Innovation
  1. Bootstrapping can significantly improve photodiode amplifier performance by minimizing the impact of parasitic capacitance. This helps in amplifying fast-changing signals better.
  2. A voltage follower in the circuit helps keep the photodiode at the same voltage, preventing internal charging and making it act like an ideal current source.
  3. While bootstrapping boosts performance, real-life limitations exist, like bandwidth and impedance, which need to be considered for accurate designs.

Nobel Prize to the Statistical Physics of artificial neural networks

Complexity Thoughts • 379 implied HN points • 08 Oct 24
🔬 Science Physics Machine Learning Artificial Intelligence Computational Models Statistical Methods
  1. John J. Hopfield and Geoffrey E. Hinton won the Nobel Prize for their work on artificial neural networks. Their research helps us understand how machines can learn from data using ideas from physics.
  2. Hopfield's networks use energy minimization to recall memories, similar to how physical systems find stable states. This shows a connection between physics and how machines learn.
  3. Boltzmann machines, developed by Hinton, introduce randomness to help networks explore different configurations. This randomness allows for better learning from data, making these models more effective.

Inverse Problems

arg min • 515 implied HN points • 03 Oct 24
🔬 Science Mathematics Statistics Physics Engineering Computer Science
  1. Inverse problems help us create images or models from measurements, like how a CT scan builds a picture of our insides using X-rays.
  2. A key part of working with inverse problems is using linear models, which means we can express our measurements and the related image or signal in straightforward mathematical terms.
  3. Choosing the right functions to handle noise and image characteristics is crucial because it guides how the algorithm makes sense of the data we collect.

Building a phosphorescence detector

lcamtuf’s thing • 2652 implied HN points • 27 Nov 24
🔬 Science Physics Engineering Research Technology Materials
  1. There isn't much information available on natural phosphorescence, so creating a detector can help explore its presence in everyday items.
  2. The device design prioritizes speed and sensitivity to detect phosphorescence briefly brought out by UV light, using specific electronics like photodiodes and amplifiers.
  3. Experimenting with common household materials showed that some items, like powdered milk and natural ruby, exhibit weak phosphorescence, although many other items didn't show any notable glow.

Counting dimer tilings

A Piece of the Pi: mathematics explained • 36 implied HN points • 21 Feb 25
🔬 Science Mathematics Combinatorics Physics Statistics Theory
  1. Dimer tilings involve arranging domino-shaped pieces on grids, and how many ways you can arrange them can vary based on the layout. For example, on a 3x3 grid with one space empty, there are 18 different arrangements.
  2. If at least one dimension of a rectangle is even, it's possible to cover it completely with dimers. However, if both dimensions are odd, it's impossible to cover them without leaving gaps.
  3. There are mathematical patterns and theorems, like Gomory's Theorem, that help understand how to tile grids with dimers. These principles can show when tiling is possible based on the arrangement and color of squares.

⚛️🌟 Our fusion future: A Quick Q&A with … nuclear engineer Michael Ford

Faster, Please! • 456 implied HN points • 21 Jan 25
🔬 Science Energy Engineering Physics Technology Research
  1. Fusion energy has great potential and is seen as safer than fission because it doesn't have the same risks of catastrophic accidents.
  2. Many companies are investing in fusion technology, which is leading to a quicker development pace than in the past.
  3. Public perception and understanding of fusion will be important for its acceptance and can affect the costs and deployment of fusion power systems.

Antigravity and the Deep State

Tao Lin • 959 implied HN points • 06 Aug 24
🔬 Science Physics Technology Engineering Military UFOs
  1. Antigravity is the idea of controlling gravity, but most scientists say it's impossible based on current physics theories.
  2. Some researchers believe that experiments with antigravity technology started over a century ago and involved famous inventors like Nikola Tesla.
  3. In the 1950s, there was much excitement about antigravity and its potential for new aircraft, but after that, discussions stopped, possibly because the technology became classified.

Trò chơi của Diophantus

Thái | Hacker | Kỹ sư tin tặc • 2037 implied HN points • 27 Jun 24
🔬 Science Mathematics History Physics Astronomy Data science
  1. The game of Diophantus, an ancient Greek mathematician, has had a lasting impact on cryptography and internet security, with the basis of elliptic curve cryptography originating from his mathematical puzzles.
  2. Diophantus's famous book 'Arithmetica' went missing for centuries but resurfaced to contribute to the advancements in mathematics, leading to significant discoveries like Fermat's Last Theorem.
  3. The study of elliptic curves, inspired by concepts like Kepler's study of ellipses, has become a central focus in mathematics, intersecting various branches like number theory, algebra, and geometry, and even impacting modern technology such as Bitcoin security.

The Origins of Deutsche Physik (1910s)

Cantor's Paradise • 363 implied HN points • 06 Jan 25
🔬 Science Physics History Politics Philosophy Mathematics
  1. The conflict in the physics community during the 1910s was largely about differing views on science and the influence of World War I. German physicists felt pressure to defend national pride while dealing with the rise of theoretical physics led by figures like Einstein.
  2. There was a significant clash between experimentalists and theorists, with older physicists struggling to accept new ideas. Many were uncomfortable with Einstein's theories because they felt too abstract and removed from traditional experimental methods.
  3. As political tensions grew, the conflict transformed into overt anti-Semitism, particularly targeting Einstein. Some physicists expressed nationalistic and racial ideologies, which later aligned with the Nazi agenda.

4.5 An Introduction to Electromagnetic Models

Fields & Energy • 279 implied HN points • 28 Aug 24
🔬 Science Physics Energy Electromagnetism Models Theory
  1. Electromagnetic energy can flow along wires due to charge imbalances. This creates electric and magnetic fields that help guide the energy.
  2. There are different viewpoints on what influences electromagnetic behavior the most: charges and currents, fields, or energy itself. Each aspect plays a role in how energy moves.
  3. Understanding these concepts can lead to better insights into electromagnetic models, but it can be complex since many elements are connected and affect each other.

4.4.2 The Catt Question

Fields & Energy • 319 implied HN points • 21 Aug 24
🔬 Science Electromagnetism Electricity Physics Energy Engineering
  1. When a voltage is applied to a transmission line, it creates a net positive charge in the top wire and a net negative charge in the bottom wire. This happens as electrons move under the influence of the electric field set by the voltage.
  2. While it seems like charge must move quickly with the wavefront, it is actually the density of charges that changes. The actual movement of electrons is slow compared to the speed of light.
  3. Understanding how charges interact with electric fields helps explain electrical conductivity and related effects. Electromagnetic phenomena involve more than just moving charges; the interaction of fields and energy is also crucial.

Physics Professors Are Using AI Models as Physics Tutors

The Algorithmic Bridge • 552 implied HN points • 27 Dec 24
🕹 Technology AI Education Science Computing Physics
  1. AI is being used by physics professors as personal tutors, showing its advanced capabilities in helping experts learn. This might surprise people who believe AI isn't very smart.
  2. Just like in chess, where computers have helped human players improve, AI is now helping physicists revisit old concepts and possibly discover new theories.
  3. The acceptance of AI by top physicists suggests that even in complex fields, machines can enhance human understanding, challenging common beliefs about AI's limitations.

4.4.1 How Do Transmission Lines Work?

Fields & Energy • 319 implied HN points • 14 Aug 24
🔬 Science Physics Electromagnetism Engineering Technology Mathematics
  1. Transmission lines work by sending electrical signals through wires, where one wire gets a negative charge and the other gets a positive charge. This creates electric fields that help move energy along the line.
  2. To avoid signal loss and distortion, it's important to balance the electric and magnetic energies in transmission lines. If they are not balanced, the signal can get messed up over long distances.
  3. Oliver Heaviside developed key equations that describe how signals travel through transmission lines. His work highlighted the importance of using both electric and magnetic energies to achieve clear signal propagation.

An Introduction to Quantum Entanglement

Fields & Energy • 279 implied HN points • 18 Aug 24
🔬 Science Physics Quantum Technology Communication Innovation
  1. Quantum entanglement happens when two particles are linked, so changing one changes the other right away, no matter how far apart they are. It's a strange and fascinating concept that Einstein called 'spooky action at a distance.'
  2. This effect has practical uses like Quantum Key Distribution (QKD) for super secure communication. But there are challenges, such as keeping the entanglement stable and dealing with issues that disrupt it over long distances.
  3. Even though quantum tech is still complex and expensive, it might inspire new ideas for amateur radio operators. Staying informed about these advancements could lead to innovative practices in their field.

The Story of the Telegrapher's Equations

Fields & Energy • 259 implied HN points • 16 Aug 24
🔬 Science Physics Mathematics History Technology Engineering
  1. Oliver Heaviside was a young scientist who created the Telegrapher's Equations in 1876. His work helped connect theories of electromagnetism to practical applications in telecommunication.
  2. Before Heaviside, the diffusion model was the main idea for how signals traveled. Heaviside improved this by showing that signals could travel as waves instead of just spreading out slowly.
  3. The development of these equations was influenced by earlier mathematicians like Fourier and scientists like Lord Kelvin. Heaviside's contribution built on their ideas and advanced the understanding of signal transmission over long distances.

The Birth of Transmission Line Theory

Fields & Energy • 279 implied HN points • 09 Aug 24
🔬 Science Physics History Mathematics Electromagnetism Engineering
  1. The first Transatlantic Telegraph Cable in 1858 was crucial for developing transmission line theory. It helped researchers understand how to send messages over long distances.
  2. Lord Kelvin created an early model for long cables, focusing on how to evenly spread resistance and capacitance. This helped explain why the first cable failed.
  3. Oliver Heaviside later added the concept of inductance to the equations, which improved the understanding of transmission lines even further.

This week: Bacteria anticipate the seasons! Placebos activate the same neurons as anesthesia! And don’t touch radio towers with hot dogs.

Niko McCarty • 79 implied HN points • 07 Sep 24
🔬 Science Biology Neuroscience Physics Mathematics Environmental Science
  1. Bacteria can sense changes in seasons and adapt to prepare for colder weather. This helps them survive better when temperatures drop.
  2. Placebos work by activating the same brain neurons as pain relief drugs like anesthesia. This shows how our mind can influence our body’s responses.
  3. A fun fact: touching a hot dog to a radio tower can turn it into a speaker. Just a quirky reminder to be careful with food and electronics!

Identifying bottlenecks in networks

A Piece of the Pi: mathematics explained • 48 implied HN points • 03 Feb 25
🔬 Science Mathematics Networks Physics Statistics Logic Analysis
  1. Bottlenecks in networks are crucial points that can slow down communication or movement. Identifying these points helps understand how the entire network functions.
  2. Networks can be made up of different regions that are linked by these bottlenecks. Recognizing connections between these regions is important for overall analysis.
  3. Knowing where the bottlenecks are can help improve the efficiency of networks, whether in transportation or social connections. This can lead to better planning and resource allocation.

4.3.1 Skin Depth & Litz Wire

Fields & Energy • 299 implied HN points • 17 Jul 24
🕹 Technology Electronics Engineering Physics Energy
  1. Skin depth refers to how electric current mainly flows close to the surface of a wire, especially at high frequencies. This means most of the current doesn't penetrate deep into the conductor.
  2. Litz wire is made up of many fine strands that help reduce resistance by allowing current to flow through a larger area. This is especially useful at high frequencies where skin depth is very small.
  3. Using litz wire not only reduces energy loss due to resistance but also makes wires more flexible and less likely to fail mechanically compared to solid wires.

No, Sora has not “learned physics”

Marcus on AI • 3596 implied HN points • 02 Mar 24
🕹 Technology AI Physics Modeling
  1. Sora is not a reliable source for understanding how the world works, as it focuses more on how things look visually.
  2. Sora's videos often depict objects behaving in ways that defy physics or biology, indicating a lack of understanding of physical entities.
  3. The inconsistencies in Sora's videos highlight the difference between image sequence prediction and actual physics, emphasizing that Sora is more about predicting images than modeling real-world objects.

How to Measure Molecules

Asimov Press • 367 implied HN points • 17 Nov 24
🔬 Science Physics Chemistry History Experimentation Mathematics
  1. In the late 19th century, Lord Rayleigh measured the size of a single molecule using simple materials like oil and water. This clever experiment showed how basic observations can lead to important scientific discoveries.
  2. Benjamin Franklin also made significant observations about oil on water in the 18th century, but he didn't calculate the size of molecules. His work laid the groundwork for future scientists like Rayleigh.
  3. Rayleigh's experiment demonstrated that you don’t always need complex tools to make groundbreaking discoveries. Even simple experiments can provide valuable insights that inspire later research.

🚀 SpaceX is making a space Mayflower voyage possible

Faster, Please! • 456 implied HN points • 01 Nov 24
🔬 Science Space Exploration Astrobiology Physics Technological Innovation Engineering
  1. SpaceX is making space travel cheaper and more accessible, which could allow for new settlements in space. This change could make colonizing asteroids a real possibility.
  2. NASA's Artemis program has spent a lot of money without achieving its goals, raising questions about its effectiveness. Some people believe that commercial companies like SpaceX could do these missions more efficiently and at lower costs.
  3. The idea of colonizing other planets can be compared to historical migrations on Earth, showing that private ventures may succeed better than expensive government projects. Learning from past colonization might help humanity settle in space.

4.3 Actions at a Distance: Fluids or Fields?

Fields & Energy • 259 implied HN points • 10 Jul 24
🔬 Science Physics Electricity Technology Engineering Energy
  1. Electricity can't really be thought of as a fluid. It has unique properties that can't be explained by the fluid model, especially in AC systems.
  2. Capacitors and inductors operate using electric and magnetic fields rather than fluids. This makes it easier to understand how they work.
  3. Transformers also rely on these fields. Their functionality shows that electric effects can occur at a distance, which a fluid model fails to explain.

4.2.1 Ancient Views

Fields & Energy • 319 implied HN points • 26 Jun 24
🔬 Science Physics History Electricity Magnetism
  1. Ancient civilizations had early insights about magnets and electricity. For example, Thales discovered static electricity from amber and believed magnets had a 'soul' because they moved metal.
  2. The compass became crucial for navigation by the sixteenth century. Mariners relied on it heavily, and misdirecting a ship was seriously punished, reflecting the compass's importance.
  3. William Gilbert made significant contributions to the understanding of magnetism and electricity. He proposed that the Earth is like a giant magnet and identified various materials that produce electric effects.

4.2.2 Fluid Theories of Electricity

Fields & Energy • 259 implied HN points • 03 Jul 24
🔬 Science Electricity Physics History Technology Chemistry
  1. Electricity was thought to behave like a fluid that could flow through conductors, which helped scientists understand how it could be transmitted over distances.
  2. Benjamin Franklin proposed a one-fluid theory of electricity, categorizing electricity into 'positive' and 'negative' charges, which laid the groundwork for future electrical theories.
  3. Alessandro Volta created the first battery, making it possible to study electricity as a continuous flow, leading to advancements in electrical science and technology.

I Know That I Know Nothing

Fields & Energy • 339 implied HN points • 17 Jun 24
🔬 Science Physics Philosophy Research Education
  1. Admitting you don't know something is important for growth. It helps you start fresh and build better understanding.
  2. Real science often challenges the current beliefs. Great discoveries come when people realize the accepted ideas might be wrong.
  3. Being open to being wrong can lead to better learning. It's key for scientists to question what they think they know.

The Right-Hand Rule for Radiation

Fields & Energy • 499 implied HN points • 29 Apr 24
🔬 Science Physics Electromagnetism Energy Radiation Research
  1. The right-hand rule for radiation helps us understand how electromagnetic energy behaves. It's a simple concept that suggests the direction of radiation can be figured out using your right hand.
  2. Radiation doesn't just come from single charges; it comes from interactions between charges. If a charge is isolated, it doesn't radiate any energy on its own.
  3. Understanding the difference between fields and energy in electromagnetism is important. They work together but behave differently, and grasping this can help us solve complex problems in physics.

Constructing space-filling curves

A Piece of the Pi: mathematics explained • 90 implied HN points • 30 Dec 24
🔬 Science Mathematics Physics Biology Chemistry Engineering
  1. Space-filling curves, like the Hilbert curve, can fill a whole area by connecting points in a specific way through iterations. They start small and grow by adding more points and connections at each step.
  2. Different seeds can lead to different types of curves. Each seed can be developed using two choices for how to connect the points, leading to many possible variations.
  3. The process used to create these curves can also be reversed. By looking at a curve and breaking it down, you can see how it was made step by step.

"Oliver Heaviside. An Appreciation : The Personal Equation : The Work of a Genius Elucidated"

Fields & Energy • 279 implied HN points • 10 Jun 24
🔬 Science Physics Engineering Mathematics History Biography
  1. Oliver Heaviside was a genius who contributed greatly to electrical science but was often misunderstood and neglected during his life. His work wasn't acknowledged until long after he had passed away.
  2. Heaviside developed important theories on cable signaling and electromagnetic waves, introducing many key terms that are still used today. His insights helped improve how signals could be transmitted over long distances, which was crucial for communication.
  3. Despite his brilliance, Heaviside lived a reclusive life and struggled financially. He preferred to work alone and only began to receive recognition later in life, which made him a complex figure in the world of science.

4.1 Heaviside, Poynting, & Energy Flow

Fields & Energy • 239 implied HN points • 12 Jun 24
🔬 Science Physics Energy Electromagnetism Theories Mathematics
  1. Poynting and Heaviside explained how energy moves through space, not just through wires. They believed that energy travels through the surrounding medium as it shifts from one spot to another.
  2. They challenged the traditional 'fluid' model of electricity, saying that while current flows through wires, the energy actually flows outside of them. This highlights the importance of electric and magnetic fields in energy transfer.
  3. The debate between the fluid model and the electromagnetic theory showed that although the latter was complex, it provided a more accurate understanding of how energy moves in electrical systems.

4.0 Electromagnetism Comes of Age

Fields & Energy • 259 implied HN points • 05 Jun 24
🔬 Science Physics Electromagnetism Innovation Technology History
  1. Oliver Heaviside improved upon Maxwell's ideas about electromagnetism. He made complex concepts simpler and more useful, opening doors for new technologies.
  2. Heaviside's work helped solve many technical issues with telegraphy, making long-distance communication possible. His innovations changed how electrical signals were sent across wires.
  3. Heaviside created important terms used in electronics today and developed a simplified way to describe energy flow in electromagnetic fields. His contributions are still fundamental in understanding electromagnetism.