The hottest Physics Substack posts right now

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The 24-hour Day That Isn't 24 Hours, Did You Know?

Stemble - for the love of STEM! β€’ 0 implied HN points β€’ 27 Jun 23
πŸ”¬ Science Astronomy Physics STEM
  1. Earth's rotation isn't a perfect 24-hour day due to its speed variations caused by gravitational interactions with the Moon and Sun.
  2. The time taken for the Earth to spin once on its axis relative to distant stars is 23h 56m 4.1s, but it needs an extra 3m 55.9s to complete a 24-hour solar day relative to the Sun.
  3. Leap seconds are added to our timekeeping to adjust for Earth's inconsistent rotation speed, managed by the International Earth Rotation and Reference Systems Service.

4. Einstein's Cross

Qissah β€’ 0 implied HN points β€’ 29 Jul 23
πŸ”¬ Science Physics Space Theory Light
  1. Despite challenges like heavy rain, life in the city continues as usual.
  2. Gravitational lensing, as predicted by Einstein, explains phenomena like Einstein's Cross.
  3. An intriguing thought: what if all stars we see are repetitive images of one lonely star?
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Small follow-ons

Bram’s Thoughts β€’ 0 implied HN points β€’ 07 Dec 23
πŸ”¬ Science Mathematics Technology Physics Engineering
  1. Fermat's Last Theorem is a level 1 question that an ordinary Busy Beaver can answer.
  2. The Twin Primes Conjecture is a level 2 question requiring a level 2 Busy Beaver with access to a level 1 Busy Beaver oracle.
  3. Level 3 questions are more difficult and less common in mathematics compared to level 2 questions.

Book Review: "The Great Mental Models: Physics, Chemistry and Biology" Vol. 2 - by Farnam Street 4/5

Poczwardowski Notes β€’ 0 implied HN points β€’ 01 Feb 23
πŸ”¬ Science Physics Chemistry Biology Mental models
  1. The second volume of 'The Great Mental Models' explores physics, chemistry, and biology, offering practical and timeless concepts that can improve our thinking.
  2. The second book maintains the high quality aesthetic of the first volume but feels more practical and grounded in the laws of nature.
  3. Exploring concepts from various scientific branches, such as those presented in the book, supports multidisciplinary thinking, helping us solve problems better and avoid repeating mistakes.

Links #3

Splitting Infinity β€’ 0 implied HN points β€’ 07 Sep 23
πŸ”¬ Science Biology Physics Engineering Computing Research
  1. The use of genetically modified neurons to improve MRI imaging of the brain by producing protein-based contrast agents is an intriguing idea.
  2. Real hedge funds do not seem to use certain advanced algorithms for portfolio selection despite proven performance improvement.
  3. FPGA's are versatile hardware that can be programmed for various computational tasks and have applications in fields like antennas, random number generation, and hardware security.

Links #1

Splitting Infinity β€’ 0 implied HN points β€’ 14 Jul 23
πŸ”¬ Science Physics Biology Medicine Technology Research
  1. Research is exploring deriving spacetime from simple quantum models, potentially changing how we understand gravity and space.
  2. Innovations like ultrasound for gene therapy and brain imaging are showing promise in medical advancements.
  3. Focusing on specialized models for deep learning tasks could lead to safer and more efficient AI development.

Probabilistic Risk Assessment (PRA) 's growing popularity with regulators & industries - A behind the scenes view

Beyond Harm β€’ 0 implied HN points β€’ 06 Mar 24
πŸ”¬ Science Risk Assessment Physics Mathematics Regulation
  1. Probabilistic Risk Assessment (PRA) predicts the 'frequency' of industrial accidents, but this can be misleading as it does not reveal how soon the next accident might occur.
  2. PRA has limitations due to its optimistic bias, which leads to under-predicting accident rates because it ignores important factors like climate change and technology wear-out.
  3. An alternative to PRA would be using Prescriptive Protection Design Requirements, which have been historically successful in ensuring safety without relying on probability mathematics.

The Physics of the Mind Part 1

Vic's Verdict β€’ 0 implied HN points β€’ 15 Mar 24
πŸ”¬ Science Physics Mind Thermodynamics Entropy Meaning
  1. Thoughts can be viewed as a form of energy, following the First Law of Thermodynamics. Your thoughts have sources like your experiences and food, and lead to actions and behaviors.
  2. The Second Law of Thermodynamics applies to the mind, suggesting that without active engagement in learning, relationships, or creativity, our minds decay into chaos. Fostering a sense of meaning and purpose helps combat this decay.
  3. One must identify their 'why' in the battle against entropy. Building systems, relationships, and investing in values can help endure beyond one's lifetime, much like how businesses or legacies can persist through deliberate design.

The Hilbert Space Formalism of Quantum Mechanics.

Quantum Formalism β€’ 0 implied HN points β€’ 14 Oct 23
πŸ”¬ Science Quantum Mechanics Physics
  1. Understanding the mathematical concepts of Hilbert spaces and Operators empowers in comprehending quantum mechanics and hardware.
  2. Delving into mathematics of Hilbert spaces and Operators can be beneficial for various quantum topics like error correction and machine learning.
  3. Even if you're not taking the quantum hardware course, learning about Hilbert spaces and Operators independently can be valuable for exploring quantum subjects.

Physics-informed Quantum Communication Networks: A Vision Towards the Quantum Internet.

Quantum Formalism β€’ 0 implied HN points β€’ 13 Jan 23
πŸ”¬ Science Physics Quantum Communication Networks Internet
  1. The webinar focuses on quantum communication networks with an emphasis on physical implementation and the vision of a Quantum Internet.
  2. Interested individuals can register for the webinar using the provided link to learn more about the exciting developments in quantum technology.
  3. Participants are encouraged to share the webinar details with their networks to create an interactive session with a wide audience.

Group theory course update.

Quantum Formalism β€’ 0 implied HN points β€’ 17 Oct 22
🚌 Education Mathematics Physics YouTube LinkedIn Discord
  1. Learn about the application of group theory in Origami Modular Design from a talk by Bob Miller.
  2. Explore Representation Theory for Geometric Quantum Machine Learning in the upcoming Lie Groups & Representations course.
  3. Discover the lectures on Measure Theory & Functional Analysis available on YouTube, covering topics like real analysis, sigma algebras, measures, and Borel Measures.

Lecture 04 Invitation

Quantum Formalism β€’ 0 implied HN points β€’ 01 Apr 22
🚌 Education Physics Mathematics Community Online Learning
  1. Attend BambordΓ©'s talk on Abstract Mathematical Structures for Quantum Computing on May 21st at 1:00 PM EDT by registering at the provided link.
  2. Catch up on missed live sessions of the Group Theory Crash Course by accessing the recordings on the YouTube playlist shared.
  3. Join the Discord Community at the provided link to participate in group study sessions and engage with other members.

Lecture 01 Replay

Quantum Formalism β€’ 0 implied HN points β€’ 26 Feb 22
🚌 Education Physics Online Learning
  1. The lecture was a replay on Group Theory crash course.
  2. Connectivity issues during the live session were faced probably due to a storm in the UK.
  3. Participants were encouraged to join the next live session and a Discord server, and take a short survey on technical background.

Feynman: Mathematicians vs Physicists

Quantum Formalism β€’ 0 implied HN points β€’ 07 Sep 21
πŸ”¬ Science Mathematics Physics
  1. Feynman highlighted the cultural differences between mathematicians and physicists, emphasizing that mathematicians have the freedom to do things their way without criticism.
  2. Feynman's invention of the 'Feynman Path Integral' showcased that innovative techniques can produce results even without strict mathematical rigor.
  3. The talk underlines the importance of individual freedom in pursuing different approaches to problem-solving in science.

Lecture #1 Reschedule

Quantum Formalism β€’ 0 implied HN points β€’ 15 Jun 21
🚌 Education Physics Topology
  1. The first lecture on Topology Crash Course has been rescheduled due to a funeral service on June 25
  2. Alternative dates offered are June 24, June 29, and July 2, all at 5pm BST
  3. Participants are reminded to review basic set-theoretic and real analysis concepts mentioned during the last Q&A session

Module II Prerequisite Schedule

Quantum Formalism β€’ 0 implied HN points β€’ 22 Apr 21
🚌 Education Physics Webinar Online Learning
  1. Module II will likely start on June 25th, with a live session planned for the upcoming Tuesday to discuss the approach and required set-theoretic concepts.
  2. If you can't attend the live session, it will be available later on their YouTube channel, ensuring you don't miss out on important information.
  3. The session will cover the structure and various topics of the prerequisite to prepare quantum enthusiasts for the module, creating an opportunity for learning.

Latest Community updates

Quantum Formalism β€’ 0 implied HN points β€’ 12 Apr 21
🚌 Education Mathematics Physics Topology Geometry
  1. The Lie Theory prerequisite mini-series will focus on point-set topology, metric spaces, and basics of differentiable manifolds.
  2. Reviewing basics of set theory, including intersections, unions, Cartesian products, and maps between sets, is recommended for the upcoming lectures.
  3. While the Lie Theory module may not be sufficient to understand Eric Weinstein's 'Geometric Unity' paper, it provides a foundational knowledge base that can ease the understanding of complex topics in differential geometry and topology.

Lie Theory Module Prerequisite

Quantum Formalism β€’ 0 implied HN points β€’ 30 Mar 21
🚌 Education Mathematics Physics
  1. Next module's prerequisite sessions are expected to start in June with a focus on Point-Set Topology & Metric Spaces.
  2. Following topics will include Topological Manifolds 101 and Representation Theory 101 before progressing to Lie Theory in Autumn.
  3. An additional free course planned by Zaiku Group later this year will cover Algebraic Topology & Topological Data Analysis, which will overlap with the prerequisite sessions.

Session 15 on YouTube

Quantum Formalism β€’ 0 implied HN points β€’ 16 Jan 21
πŸ”¬ Science Physics
  1. Session 15 is now available on YouTube with a fixed typo.
  2. There is a plan to create a mini-lecture series on representation theory after the foundation module and before the advanced module.
  3. The mini-lecture series on representation theory might take place in the summer.

Session 15 Reminder

Quantum Formalism β€’ 0 implied HN points β€’ 14 Jan 21
🚌 Education Science Mathematics Physics Quantum
  1. The session covers topics like Eigenvectors & Eigenvalues, Spectrum & Eigenspaces, Diagonalization, and The Spectral Theorem for Hermitian matrices.
  2. Newcomers are welcome, but may find it challenging if they haven't covered previous sessions or don't have a background in relevant university-level physics/mathematics.
  3. The upcoming session will focus on Quantum Axioms, the Shut up & Calculate Challenge, and Study Material Comments.

Lecture 14 Invitation

Quantum Formalism β€’ 0 implied HN points β€’ 04 Jan 21
🚌 Education Physics Mathematics
  1. The invitation for Lecture 14 has been shared with details for the upcoming session.
  2. Newcomers are welcome, but it is advised to have a background in university-level physics and mathematics to follow along effectively.
  3. The registration link for the session is available for those who are interested in attending.

Last 2020 Lecture!

Quantum Formalism β€’ 0 implied HN points β€’ 17 Dec 20
🚌 Education Physics Mathematics
  1. The last session of 2020 will cover topics like normalised vectors, orthogonal vectors, and orthonormal bases.
  2. The lecture will also discuss topics such as bras, the dual space, and the Riesz Representation Theorem.
  3. Newcomers are welcome to join the lecture, but may find it challenging if they haven't attended previous sessions or lack an advanced background in physics/mathematics.

Lecture 10

Quantum Formalism β€’ 0 implied HN points β€’ 27 Nov 20
πŸ”¬ Science Physics Mathematics
  1. The lecture covers the general linear group GL(2, C) and the special linear group SL(2, C).
  2. Future sessions will discuss the unitary group U(2) and the special unitary group SU(2).
  3. There are concerns about YouTube running ads on videos, potentially leading to removal of lecture videos due to content disagreements and algorithm filtering issues.

Lecture 9 Invite + Nicolas Bourbaki

Quantum Formalism β€’ 0 implied HN points β€’ 10 Nov 20
πŸ”¬ Science Mathematics Physics
  1. Invitations have been sent out for the next live session, so make sure to check your email if you attended the previous one.
  2. There is a group called Nicolas Bourbaki, a secretive math society that has notable members like Jean-Pierre Serre and Alain Connes.
  3. Noncommutative Geometry and C*-algebras, topics linked to physics, will be covered in the advanced module next year.

Influential Mathematicians: Frigyes Riesz

Quantum Formalism β€’ 0 implied HN points β€’ 15 Jul 20
πŸ”¬ Science Mathematics Quantum Mechanics Functional Analysis Physics Theory
  1. Frigyes Riesz was a significant mathematician who made key contributions to functional analysis and operator theory, impacting areas like physics and Hilbert spaces.
  2. His work, including the Riesz-Fischer theorem, influenced the development of quantum theory, showing the unitary equivalence of different quantum theories.
  3. Riesz is known for foundational work in Functional Analysis, which is crucial for the mathematical formalism of quantum mechanics, and concepts like Dirac's bracket notation make sense thanks to Riesz representation theorem.

Influential Mathematicians: Emmy Amalie Noether

Quantum Formalism β€’ 0 implied HN points β€’ 29 Jun 20
πŸ”¬ Science Mathematics Quantum Algebra Abstract Physics
  1. Emmy Noether, despite facing discrimination as a woman in academia, made significant contributions to mathematics and physics.
  2. Noether's work in invariant theory and abstract algebra, along with her collaborations, influenced the development of advanced algebraic tools used in treating quantum formalism.
  3. Noether played a mentorship role in shaping the career of another influential female mathematician, Grete Hermann, who made important contributions to the foundations of quantum mechanics.

Influential Mathematicians: David Hilbert

Quantum Formalism β€’ 0 implied HN points β€’ 11 Jun 20
πŸ”¬ Science Mathematics Physics Biography
  1. David Hilbert's contributions to geometry and axiomatic methods influenced mathematics and physics significantly.
  2. Though Hilbert didn't directly work on quantum mechanics, his foundational work on integral equations paved the way for the development of quantum formalism.
  3. Hilbert's interest in applying axiomatic methods to physics led to his famous 'Sixth Problem,' advocating for treating physics with mathematical axioms.

Physics vs Surrealism

Cybernetic Forests β€’ 0 implied HN points β€’ 07 Mar 21
🎨 Art & Illustration Photography Surrealism Physics Electronic Music Visual Arts
  1. Berenice Abbott used her art to make physics compelling and accessible, rather than using physics to create art.
  2. In the past, there was a fear in the scientific community that public engagement in science would corrupt the purity of science.
  3. Science communication should be seen as a form of research that extends understanding and application of knowledge, not just as PR for scientists.

Cholesterol's Hydroxyl Group

Harnessing the Power of Nutrients β€’ 0 implied HN points β€’ 09 Nov 08
πŸ”¬ Science Chemistry Biology Physics
  1. The hydroxyl group in cholesterol is important because it is polar, having positive and negative poles, and is water-soluble.
  2. Water is a polar molecule due to its hydroxyl groups, demonstrating how opposite charges attract each other.
  3. Cholesterol is an example of an amphipathic molecule, with a water-soluble polar region and a water-insoluble non-polar region.

Atoms and Molecules

Harnessing the Power of Nutrients β€’ 0 implied HN points β€’ 06 Nov 08
πŸ”¬ Science Chemistry Biology Physics
  1. Atoms are the basic building blocks of matter, made up of protons, neutrons, and electrons. They form by balancing positive and negative charges.
  2. Covalent bonds are formed when atoms share electrons to fulfill a full outer shell, creating molecules like water.
  3. Ionic bonding occurs when atoms transfer electrons, resulting in charged ions that stick together oppositely to form compounds like table salt.

$(-1)^2$

ThΓ‘i | Hacker | Kα»Ή sΖ° tin tαΊ·c β€’ 0 implied HN points β€’ 10 Jan 16
πŸ”¬ Science Mathematics Physics Number Theory
  1. Imaginary numbers like $i$ are not real because there isn't a real number whose square is -1, pushing the boundaries of mathematical concepts beyond reality.
  2. The rule stating that multiplying two negative numbers results in a positive number, like $(-1) * (-1) = +1$, is a construct by mathematicians to maintain consistency in arithmetic.
  3. Mathematicians create and manipulate rules in pure math to explore interesting results and sometimes stumble upon practical applications, demonstrating the power of abstraction in mathematics.

Thα»­ nghiệm MathJax

ThΓ‘i | Hacker | Kα»Ή sΖ° tin tαΊ·c β€’ 0 implied HN points β€’ 26 Sep 13
πŸ”¬ Science Mathematics Physics
  1. The author discovered MathJax as a way to write mathematical formulas on the web, finding it visually appealing on Chrome in Linux.
  2. MathJax seemed to not work on Chrome in Android, prompting the author to wonder about its functionality on other platforms and browsers.
  3. The post includes mathematical formulas like Cauchy-Schwarz inequality, Fermat's little theorem, and Euler's beautiful identity, showcasing the use and testing of MathJax for such expressions.