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Universal Quantum Computing as a Markov Chain

Let’s say you have a probabilistic computer with a single bit of memory. Some algorithms on the computer will stochastically flip the single bit of memory such that its new value will be uniformly distributed with a 50% chance of being 0 and a 50% chance of being 1. Other programs will place it into a degenerate distribution, meaning it either has 100% chance of being 0 every time you run the program, or other programs will produce 1 100% of the time.

A magician tells you to run one of the programs in one of the two categories of your choosing and then copy the computer’s memory state onto a thumb drive and hand it to him. You pick one, run the program, copy the bit of the memory to your thumb drive, then hand it to the magician. The magician then does something with the thumb drive you cannot see, then looks up at you and tell you exactly what category the program you ran to produce that bit came from.

Curious, you repeat this many times over: you run a program from one of the two categories (degenerate or uniform), copy the bit value produced from the algorithm, and then hand the thumb drive to the magician. Each and every time he always correctly guesses which category of program was ran to produce it.

Feynman: The Past and Future Are the Same Thing

The past and future are the same thing | feynman on time symmetry.

Discover one of physics’ most mind-bending secrets: the fundamental laws of nature don’t know which way time flows! In this exploration of Feynman’s ideas on time symmetry, we dive deep into how the equations of physics work equally well forwards and backwards, why positrons are electrons moving backward through time, and how the Wheeler-Feynman absorber theory suggests the future might influence the past.

From billiard balls to quantum mechanics, from Maxwell’s equations to the mystery of why we remember yesterday but not tomorrow, this video unravels the beautiful symmetry hidden beneath our everyday experience of time.

Topics Covered:
• Time symmetry in fundamental physics
• Positrons as electrons traveling backward in time
• Wheeler-Feynman absorber theory
• The thermodynamic arrow of time
• Path integral formulation and quantum mechanics
• Why time appears to flow in one direction
• CP violation and the weak nuclear force.

Perfect for physics enthusiasts, students, and anyone curious about the nature of time and reality.

⚠️ DISCLAIMER: This is AI-generated content created in the style of Richard Feynman’s teaching approach. The script synthesizes information from various sources about Feynman’s work and ideas in theoretical physics, including his lectures, published papers, and documented contributions to quantum electrodynamics and time-symmetric theories. While based on authentic concepts from Feynman’s career, this is an educational interpretation and not actual recorded material from Richard Feynman.

New methods can help study the phenomenon of turbulence

In his doctoral thesis, Michael Roop develops numerical methods that allow finding physically reliable approximate solutions to nonlinear differential equations used to model turbulence.

Many processes in nature can be described by differential equations, but only a few of them can be solved explicitly with solutions in formulas. This is the motivation for developing numerical equations to find approximate solutions. The numerical equations developed in Roop’s thesis have a particular focus on geometric properties. Though the thesis is mathematical, the problems it addresses originate in physics and mainly have to do with magnetohydrodynamic (MHD) turbulence.

“It is difficult to define turbulence rigorously. Intuitively, you can think of the turbulent behavior when a fluid moves, but it is very hard to predict how it will behave in the future. It looks chaotic though there is no randomness in the models of motion.”

Quantum Fourier transform reaches 52 qubits, shattering the previous 27-qubit record

The spin-off company ParityQC has implemented the largest quantum Fourier transform ever reported using an IBM quantum computer, thereby setting a new milestone on the path toward the industrial application of quantum computers. The quantum Fourier transform is a cornerstone algorithm with applications in cryptography, financial modeling, and materials science.

Innsbruck-based quantum architecture company ParityQC performed a quantum Fourier transform using 52 superconducting qubits on an IBM Heron quantum processor. This surpasses the previous record of 27 qubits, which was set two years ago using an ion-trap quantum computer. The results were published this week on the arXiv preprint server.

“This milestone was only possible through the synergy of IBM’s latest quantum hardware and the ParityQC Architecture, which unlocked an exponential improvement in efficiency,” say Wolfgang Lechner and Magdalena Hauser, Co-CEOs of ParityQC. “What we are witnessing is European quantum innovation taking a global lead in translating theoretical potential into real-world performance.”

CT and MRI LI-RADS Treatment Response Assessment 2024: Core Concepts for Clinical Practice

Post-treatment HCC imaging just got clearer. The updated 2024 LI-RADS TR algorithm refines criteria for radiation vs non-radiation therapies and adds MRI features to better detect viable tumor, key for accurate response assessment and management.


Multiple locoregional therapies are available for HCC, with imaging findings specific to each modality. The updated 2024 CT and MRI LI-RADS TR assessment criteria provided distinct algorithms for use after nonradiation or radiation-based therapies, simplified the definition of viable disease, and incorporated MRI ancillary features to enhance detection of tumor viability. These updated criteria can improve diagnostic accuracy, resulting in more effective clinical management of HCC.

Quantum-inspired algorithm solves 268 million-site quasicrystal simulation in a heartbeat

Quantum technologies like quantum computers are built from quantum materials. These types of materials exhibit quantum properties when exposed to the right conditions. Curiously, engineers can also trigger quantum behavior by manipulating a material’s structure; for example, by stacking layers of graphene on top of each other and twisting them to create a moiré pattern, which suddenly turns them into a superconductor.

The layers can be arranged in increasingly complex ways all the way to quasicrystals and super-moiré materials. The fundamental problem is that scientists must first calculate the properties of potential new materials to predict if they could be useful. Quasicrystals, for example, are so complex they can require processing more than a quadrillion numbers—far beyond the capacity of the world’s most powerful supercomputers.

Now researchers at Aalto University’s Department of Applied Physics have shown how a quantum-inspired algorithm makes solving these colossal, non-periodic quantum materials possible in a heartbeat. The research is published in the journal Physical Review Letters as an Editor’s suggestion.

Spatiotemporal light pulses could secure optical communication by masking data

Researchers at Ben-Gurion University of the Negev have developed a new approach to secure optical communication that hides information in the physical structure of light, making it difficult for unauthorized parties to intercept or decode. The study addresses a growing challenge: advances in quantum computing are expected to weaken many of today’s encryption methods. While most security solutions rely on complex mathematical algorithms, this research adds protection earlier in the process—during the transmission of the signal itself.

The research was led by Dr. Judith Kupferman and Prof. Shlomi Arnon from the School of Electrical and Computer Engineering at Ben-Gurion University of the Negev. The findings were published in Optical and Quantum Electronics.

The researchers propose a communication method based on specially shaped light pulses, known as spatiotemporal optical vortices. These light beams are designed so that their key features are not visible in standard measurements.

Scientists Make Breakthrough on 40-Year-Old 2D Physics Puzzle

Why do patterns emerge as surfaces grow, whether in crystals, flames, or living systems? Physicists have long turned to the Kardar–Parisi–Zhang (KPZ) equation, proposed in 1986, as a unifying description of these processes. This theory captures how randomness and nonlinear effects shape growth across vastly different systems, from spreading bacterial colonies to data-driven algorithms.

Now, researchers at the University of Würzburg have taken a major step toward confirming just how universal this idea really is. After earlier success in one dimension, they have demonstrated for the first time that KPZ behavior also governs growth in two-dimensional systems, a milestone that had remained experimentally out of reach.

AI chatbot teaches AI ‘student’ to love owls, even after data is scrubbed

Large language models (LLMs) can teach other algorithms unwanted traits, which can persist even when training data has been scrubbed of the original trait, according to new research published in Nature. In one example, a model seems to transmit a preference for owls to other models via hidden signals in data. The findings demonstrate that more thorough safety checks are needed when producing LLMs.

LLMs can generate datasets to train other models through a process called distillation, in which a “student” model is taught to mimic the outputs of a “teacher” model. While this process can be used to produce cheaper versions of an LLM, it is unclear which properties of the teacher model are transferred to the student.

Alex Cloud and colleagues used GPT-4.1, which was prompted to have traits unrelated to a core task (a preference for owls or certain trees, for instance), to train a student model with output consisting only of numerical data, with no references to the trait. When the resulting student was subsequently prompted, it mentioned the teacher’s favorite animal or tree over 60% of the time, compared to 12% for a student trained by a teacher with no favorite animal or tree. This effect was also observed when the student was trained on a teacher’s output that contained code instead of numbers.

Physicists Just Linked This 160 Year-Old Math Problem To Black Holes

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The Riemann Hypothesis is an open problem in maths which – if proved correct – would show us a pattern in prime numbers. The zeta function, a central part of the hypothesis, has been linked to quantum mechanics, and recently a group of physicists linked it to gravitational equations associated with black holes. What does this mean, exactly? Let’s take a look.

Paper: https://link.springer.com/article/10… mugs, posters and more: ➜ https://sabines-store.dashery.com/ 💌 Support me on Donorbox ➜ https://donorbox.org/swtg 👉 Transcript with links to references on Patreon ➜ / sabine 📝 Transcripts and written news on Substack ➜ https://sciencewtg.substack.com/ 📩 Free weekly science newsletter ➜ https://sabinehossenfelder.com/newsle… 👂 Audio only podcast ➜ https://open.spotify.com/show/0MkNfXl… 🔗 Join this channel to get access to perks ➜ / @sabinehossenfelder 📚 Buy my book ➜ https://amzn.to/3HSAWJW #science #sciencenews #physics #maths The Riemann hypothesis is a significant open problem in mathematics, deeply intertwined with number theory and its implications for physics. This video explores how the riemann zeta function, a central element of the hypothesis, connects to fundamental concepts like black hole physics and quantum gravity. Discover the ongoing mathematical research that seeks to solve this enduring mystery…

👕T-shirts, mugs, posters and more: ➜ https://sabines-store.dashery.com/
💌 Support me on Donorbox ➜ https://donorbox.org/swtg.
👉 Transcript with links to references on Patreon ➜ / sabine.
📝 Transcripts and written news on Substack ➜ https://sciencewtg.substack.com/
📩 Free weekly science newsletter ➜ https://sabinehossenfelder.com/newsle
👂 Audio only podcast ➜ https://open.spotify.com/show/0MkNfXl
🔗 Join this channel to get access to perks ➜
/ @sabinehossenfelder.
📚 Buy my book ➜ https://amzn.to/3HSAWJW

#science #sciencenews #physics #maths.

The Riemann hypothesis is a significant open problem in mathematics, deeply intertwined with number theory and its implications for physics. This video explores how the riemann zeta function, a central element of the hypothesis, connects to fundamental concepts like black hole physics and quantum gravity. Discover the ongoing mathematical research that seeks to solve this enduring mystery.

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