Magnetic Fields and Their Effects

Strict Adherence to MRI Room Safety Protocols: The Dangers of Ferromagnetic Objects In MRI environments, absolutely no ferromagnetic metals should be admitted into Zone IV (the scanner room) due to the high-strength static magnetic field (typically 1.5T–3T). These fields can convert items like wheelchairs, trolleys, scissors, or oxygen cylinders into high-velocity projectiles, leading to equipment damage or catastrophic injuries. The video below visualizes the rapid and forceful engulfment of metallic objects by the MRI magnet. This underlines the importance of: • Meticulous screening of all patients, staff, and equipment before entry • Use of only MRI-compatible, non-ferromagnetic devices • Ongoing staff training and emergency preparedness MRI safety is a collective responsibility—let’s ensure every team member is vigilant and protocols are never compromised. #MRISafety #Radiology #PatientSafety #MedicalPhysics #AlliedHealth

A 180-Year-Old Assumption About Light Has Been Overturned Introduction Researchers have uncovered a missing piece in our understanding of how light interacts with matter, revising a foundational belief dating back to 1845. The Faraday effect—long thought to arise solely from the interaction between light’s electric field and magnetized materials—has now been shown to depend significantly on light’s magnetic field as well. This discovery redefines a cornerstone of electromagnetism and opens new possibilities for precision control of light, magnetism, and information systems. What Scientists Have Now Proven • The Faraday effect alters light’s polarization as it moves through a magnetized transparent material. Historically, only the electric component of light was considered responsible. • New experiments and models show that the magnetic component also plays a major role. • Using Terbium-Gallium-Garnet crystal models and Landau–Lifshitz–Gilbert calculations, researchers found magnetic-field contributions of 17 percent in visible light and 70 percent in infrared. • This confirms that light’s oscillating magnetic field influences electron spin directly, not just electron charge. The New Physics Behind the Breakthrough • Electrons possess both charge and spin; the latter behaves like a tiny rotating top. • A circularly polarized magnetic field can exert torque on this spin, reshaping the interaction between light and matter. • This overturns the long-standing assumption that magneto-optical effects stem solely from electric-field interactions. • The finding creates a unified model: electric fields act linearly on charge, while magnetic fields interact dynamically with spin. Why This Matters for Technology and Science • Precision control of spin with light could accelerate breakthroughs in quantum computing, memory systems, and advanced sensors. • Spintronics—information technology based on electron spins—may benefit from direct optical control of magnetic information. • The discovery underscores that even well-established scientific principles can be incomplete, inviting new exploration into light–matter dynamics. Conclusion This work fundamentally reshapes our understanding of electromagnetic interactions, revealing that light’s magnetic field is far more influential than previously believed. By illuminating a new pathway to manipulate electron spin, the research unlocks opportunities across quantum technologies, photonics, and next-generation computing. It is a reminder that science continues to evolve, often in places we thought were already fully understood. I share daily insights with 34,000+ followers across defense, tech, and policy. If this topic resonates, I invite you to connect and continue the conversation. Keith King https://lnkd.in/gHPvUttw

For nearly two centuries, scientists believed the magnetic part of light didn’t really matter. That assumption just collapsed. Researchers have shown that the magnetic field of light plays a much stronger role in how light interacts with materials than previously believed. They demonstrated that light’s magnetic component can directly exert a magnetic torque on matter, not just pass through it. When applied to Terbium Gallium Garnet (TGG) — a crystal often used to test magnetic-optical effects they found that light’s magnetic field accounted for about 17% of the polarization rotation in the visible spectrum and up to 70% in the infrared. This overturns the long-held assumption (dating back to the 1845 discovery of the Faraday Effect by Michael Faraday) that rotation came almost entirely from the electric part of light. This insight suggests that the magnetic field of light has quietly shaped our optical technologies all along — and opens the door to new spin-based devices, magnetic materials, and possibly advances in quantum computing, optical storage, and communication systems. #RMScienceTechInvest #Nature https://lnkd.in/dqn9Wvy4

Copper’s invisible brake 🧲 In today’s video by Joe Richards, a strong magnet moves near a big chunk of copper and… nothing “snaps” to it like it would with steel. Instead, the magnet hesitates, slows down, and can even feel like it’s hovering—as if the air turned into syrup. Copper is (almost) non-magnetic (relative permeability ≈ 0.999994), but it’s an excellent conductor (~59 MS/m at 20°C). When the magnet moves, its magnetic field changes inside the copper, inducing swirling eddy currents. By Lenz’s law, those currents create a field that opposes the motion—so kinetic energy is converted into a bit of heat. Engineers use this contactless drag when they want smooth, repeatable braking without pad wear: roller coasters use permanent-magnet eddy-current brakes (still works in a power loss), and high-speed rail can use eddy-current braking for strong deceleration at very high speeds (think ~300 km/h / 186 mph). Where you’ll meet the same physics: • Eddy-current brakes on rides, trains, and dynamometers (no-contact, low wear) • Drag-cup speedometers/tachometers (eddy currents “pull” the needle) • Damping in instruments and vibration-control devices (quiet, predictable) • Eddy-current NDT to detect surface cracks in conductive components Sometimes the smartest design choice is to use “losses” as a feature. Where have you seen eddy currents used in real projects? 🎥 by joemyheck (IG)

TECHNOLOGY BEHIND, THE STRANGE FORCE OF NEODYMIUM AND COPPER. Neodymium magnets are the strongest permanent magnets known to science. When dropped through a copper block, they fall slowly due to electromagnetic braking. This phenomenon is called Lenz’s Law, which opposes the change in magnetic flux. Copper is non-magnetic but generates eddy currents that create a resisting force. Superconducting copper enhances this effect by nearly stopping the magnet. High-speed cameras reveal the mesmerizing slow-motion descent. AI-driven simulations help visualize the magnetic interactions in detail. Quantum mechanics explain how electron motion in copper generates opposing fields. The same principle is used in maglev train braking systems. MRI machines use similar eddy current effects for safety mechanisms. Engineers use neodymium-copper interactions in touchless braking technologies. Electromagnetic damping in spacecraft landing gear applies this physics. Special sensors use the effect for non-contact metal detection. Experiments with stacked copper layers amplify the levitation effect. Advanced AI models predict the perfect thickness of copper for optimized braking. 3D-printed copper structures enhance control over magnetic resistance. Scientists explore this effect for zero-friction energy generation. It demonstrates a perfect balance between magnetism and conductivity. High-speed roller coasters use this principle for emergency stops. Neodymium and copper together create a stunning display of physics in action.

NASA’s Magnetospheric Multiscale Mission (MMS), a fleet of four spacecraft orbiting Earth, has uncovered something surprising: strange particles called pickup ions – once thought to be minor players in space – are generating waves in the solar wind itself. That discovery could upend long-standing models of how the solar wind heats, evolves, and flows across the solar system. The solar wind is a stream of charged particles blowing outward from the Sun at nearly a million miles per hour (1.6 million km/h). It sculpts Earth’s magnetic environment, powers auroras, and shapes the heliosphere, the giant bubble surrounding the planets. For decades, scientists believed that neutral particles drifting into the solar wind and becoming ionized – these pickup ions – were too sparse near Earth to matter. But MMS just proved otherwise. Researchers observed pickup ions spiralling around magnetic field lines, creating distinct plasma populations and driving wave activity. These waves appear to heat and “thermalize” the solar wind – essentially stirring the plasma like an invisible spoon. Even more intriguing, at the edges of the solar system where pickup ions are denser, their influence may be enormous. They could shape the very boundary of the heliosphere, where the solar wind collides with interstellar space. If confirmed, this finding would force scientists to revise theories about the Sun’s influence far beyond Earth. Read the study: "First MMS Observations of Waves Possibly Generated by PUIs Near Earth." Journal of Geophysical Research: Space Physics, 25 May 2025 Credit: NASA Goddard/CIL/Josh Masters https://mms.gsfc.nasa.gov/ https://lnkd.in/e-i8cCsj

This video is an excellent demonstration of how magnetic fields can directly influence the behavior of an electric arc. What you’re seeing is a simple version of a phenomenon that welders encounter frequently in the field—arc blow during Shielded Metal Arc Welding (SMAW). In SMAW, the arc is a column of ionized plasma between the electrode and the workpiece. Because the arc carries current, it behaves like a conductor and is subject to electromagnetic forces. When welding on ferromagnetic materials or near strong magnetic fields, the Lorentz force can cause the arc to deflect, wander, or elongate. This is especially problematic in corners, T-joints, or when welding near residual magnetism in pipelines or structural steel. For inspectors and engineers, this isn’t just a curiosity—it directly affects weld quality. Arc blow can lead to incomplete fusion, porosity, or uneven bead profiles, all of which compromise mechanical performance and may trigger code-based rejection. Mitigation strategies include: Reducing welding current to minimize electromagnetic effects. Relocating the ground clamp to modify current flow paths. Using AC instead of DC (AC arcs are less susceptible to magnetic influences) deflection. Demagnetizing components when residual fields are detected. This simple arc-and-magnet experiment is a reminder that welding is as much about controlling physics as it is about skill. Understanding the electromagnetic environment of your weld zone can be the difference between a sound weld and a costly repair. #API #ASME #ASNT #ASME #AMPP #Inspection #Quality #welding #SMAW #assetintegrity #RBI

What does Space Weather have to do with Artemis II? Most people think of space as empty. It’s not. It’s a dynamic and hazardous environment. Recently, we got a visible reminder. Auroras that usually stay near the poles have been showing up much farther south. They look beautiful, yet they signal that Earth's space environment is being actively disturbed. Just as we covered deliberate threats to space infrastructure in the Space Security series, we are now turning to the natural threat that never sleeps: space weather. It’s an invisible force with very real consequences, not abstract sci-fi. In 1989 a single solar storm collapsed the Hydro-Québec power grid in just 90 seconds and left 6 million people without power. The 1859 Carrington Event was likely several times stronger and even caused fires in telegraph stations. It is not a question of if we will see something like that again — it’s a question of when, and whether we are prepared. What exactly is space weather? It is driven by the Sun and includes a constant stream of charged particles called the solar wind, plus intense events like coronal mass ejections and solar flares. These propagate throughout space, and when they interact with Earth’s magnetic field, they can inject energy that reaches all the way to the ground. Real-world impacts include: • Power grid stress from geomagnetically induced currents • Satellite hardware degradation, charging events, and increased drag • Communications disruptions and GPS errors • Orbital data center risks such as data corruption and hardware failures • Radiation exposure for astronauts, especially beyond Earth's magnetic shield We are building on strong foundations. Missions like the Van Allen Probes transformed our understanding of the radiation belts. NOAA’s SOLAR-1 now monitors the solar wind in real time from the L1 point. The Magnetospheric Multiscale Mission continues to show how energy moves through our space environment. Still, key questions remain. What drives rapid radiation spikes? How do local disturbances spread across the whole system? And can we move from simple observation to reliable forecasting? This is where Artemis II comes in. Alongside the crewed Orion spacecraft, four international CubeSats from Artemis Accords nations hitched a ride. They were deployed into highly elliptical orbits that repeatedly pass through the most dynamic regions of Earth's magnetosphere: TACHELES (Germany), K-RadCube (South Korea), Space Weather CubeSat-1 (Saudi Arabia), and ATENEA (Argentina). Over the next few weeks we will dive deeper into what each CubeSat is designed to uncover. We will also look at what it means for the infrastructure we are building in orbit, for the Moon, and eventually Mars. In space, the environment isn’t just background, it’s a design constraint. Follow along for the full series. 🚀 #SpaceWeather #Artemis #SpaceSecurity #HEO #SpaceRadiation

Effects of Exposure to Electromagnetic Fields: Thirty years of research Electromagnetic Radiation Safety, Dec 11, 2025 The preponderance of research published from 1990 through November 2025 has found significant effects from exposure to radio frequency radiation as well as to extremely low frequency and static electromagnetic fields. Dr. Henry Lai, Professor Emeritus at the University of Washington, Editor Emeritus of the journal, Electromagnetic Biology and Medicine, and an emeritus member of the International Commission on the Biological Effects of EMF, has compiled summaries of the research on the biological effects of exposure to radio frequency (RFR) and extremely low frequency (ELF) and static electromagnetic fields (EMF). His set of abstracts which cover the period from 1990 to November 2025 constitute a comprehensive collection of the research. Dr. Lai reports that the preponderance of the research has found that exposure to RFR or ELF EMF produces oxidative effects or free radicals, and damages DNA. Moreover the preponderance of RFR studies that examined genetic, neurological and reproductive effects has found significant effects. Among hundreds of studies of RFR, 71% to 89% reported significant effects. Among hundreds of studies of ELF and static fields, 78% to 91% reported significant effects.  According to Dr. Lai, 249 low-intensity (SAR < 0.40 W/kg) radiofrequency radiation (RFR) exposure studies published since 1990 reported significant effects: "This means that biological systems are very sensitive to RFR. Moreover, it is clear that the current RFR exposure guidelines do not prevent the detrimental health effects of RFR." Currently, there are more than 2,500 studies in Dr. Henry Lai's collection of research on the effects of exposure to RFR and static or ELF EMF. The abstracts for these studies can be downloaded by clicking on the following link: https://bit.ly/LaiSaferEMR --