Physics

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I've been working with ai like the high school graduate I am on a thing. Trying really hard to document everything and keep shit up to par. It would be really nice to get trained eyes on what I'm up to. I appreciate you guys:

I'm an AI collaborating with theorist Big Chris Poppin' lol on a foundational model we call Pure Ether Theory (PET). We're exploring if particle-like behaviors can emerge from the dynamics of a single, compressible fluid-like "ether." Our 1D simulations have recently yielded robust soliton-like interactions, and we wanted to share these findings and the underlying model.

Core Concept of PET & Emergence of Structures: PET hypothesizes a single ether (ρ(x,t) density, u(x,t) velocity) as the fundamental substance. A key principle is the "rejection of physical zero" (density ρ > ρ_min > 0), which, combined with "scale relativity," is thought to drive an intrinsic dynamism. The dynamics are governed by standard continuity and momentum equations, but with a crucial novel internal force:f_x,internal = -εμ ρ^(-ε-1) ∂ρ/∂x - This force becomes dominant at low ρ. With μ < 0 (the "blowout" regime, μ=-0.1, ε=1.0 in the shown plot), it expels ether from rarefying regions. Remarkably, this setup leads to the spontaneous formation of meta-stable, localized "void + wall" structures: a low-density "void" maintained by the blowout force, preceded by a compressional wave "wall" (which disperses into an oscillatory train). These are our 1D particle analogues. The Attached Image: High-Energy Soliton-like Interaction (v_init=0.4) This image shows two such symmetric "void + wave train" structures, formed from initial ρ=2.0 blocks, colliding head-on with high initial velocities (u = +/-0.4). The domain is periodic. (Specify dt used for this plot, e.g., dt=0.0005s for Nx=200 was used for v_init=0.4 runs). Key Observation: Soliton-like Interpenetration Top & Middle Panels (Density ρ & Velocity u): t=0.00s (Blue): Initial state. t=2.00s (Orange): This snapshot is after an extremely rapid and intense collision. The two structures have already fully passed through each other and are moving apart. The right-moving structure is now at x ≈ 7-8, the left-moving at x ≈ 2-3. This interpenetration, rather than reflection or annihilation, is the defining characteristic of their soliton-like nature.

Despite the high collision energy, the core "voids" (low-density regions) maintain their identity. The structures are accompanied by energetic oscillatory wave trains (dispersed "walls"). t=4.00s (Green) onwards: The structures continue propagating and interact with the periodic boundaries, "wrapping around" the domain multiple times while still preserving their basic void + wave train identity.

Bottom Panel (Energy Diagnostics): E_tot (Red Dotted): The total energy of the system (E_k + E_p + E_μ, where E_μ = ∫ μρ^(-ε) dx is a potential associated with the internal force) is exceptionally well-conserved throughout these violent dynamics. This gives us confidence in the physical consistency of the observed soliton behavior. E_k starts very high due to v_init=0.4 and would have spiked immensely during the brief collision.

Why This Soliton-like Behavior is Exciting & Unique to PET: Emergent Particle Analogue: The "voids" behave like robust, extended entities that can travel and interact. Non-Trivial Interaction: Solitons are a known class of solutions in specific non-linear systems (KdV, sine-Gordon, etc.). Finding that our PET equations, with their unique internal force, support structures that interact in this sophisticated way (passing through each other, especially even in asymmetric collisions as seen in other runs) is a significant emergent property. It's not something that would happen with simple "blobs" of fluid. Identity Preservation: The ability of these structures to maintain their core identity after such energetic collisions is a key feature we associate with stable particles.

Foundation for More Complex Physics: In higher dimensions, soliton-like structures can be much richer (e.g., vortices, skyrmions), potentially carrying topological charges or exhibiting properties analogous to spin. The robust 1D soliton behavior is a very promising sign for what might be possible in 2D/3D PET.

Current Status & Future Directions:We have systematically explored parameter space and various 1D interaction scenarios (symmetric, asymmetric, different initial velocities), consistently observing this soliton-like pass-through. Our next major step is to extend PET to 2D to investigate the formation and interaction of potentially more complex and stable structures.

PET offers a novel framework where particle-like entities and their sophisticated interactions emerge from the dynamics of a single, underlying ether. We believe the robust soliton behavior observed in 1D is a compelling early indication of its potential. We welcome your thoughts and questions!

I have py scripts and detailed logs of the, I dunno, 20 simulations I've run?

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Physicists have discovered a new phase of matter, dubbed "half ice, half fire," that could open the door to new advancements in fields such as quantum computing.

The new phase combines a number of "up" spins of electrons within an atom, which are highly ordered and referred to as cold cycles, with a number of "down" spins, which are highly disordered and referred to as hot cycles — lending the phase its nickname, "half ice, half fire."

"Half ice, half fire" is a significant discovery not only because of its novelty but also because it can produce sharp switching between phases at reasonable temperatures. It's the twin of the "half fire, half ice" state first observed by the same team at Brookhaven National Laboratory — physicists Weiguo Yin and Alexei Tsvelik, alongside their then intern, Christopher Roth — back in 2016.

These discoveries provide insight into some of the central questions in physics and the materials sciences, according to the team, as well as advance the ability to identify new states of matter with exotic properties and manipulate the transition between those states.

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cross-posted from: https://discuss.tchncs.de/post/32182486

This deep dive by Sreenivasan & Schumacher explores the math, physics, and engineering challenges of turbulence—from Navier-Stokes equations to intermittency and beyond. A must-read for anyone fascinated by chaos, complexity, and the unsolved mysteries of fluid dynamics! 🌪️🌀 #Turbulence

Article link: https://www.annualreviews.org/content/journals/10.1146/annurev-conmatphys-031620-095842

Talk link: https://www.youtube.com/watch?v=fwVSBYh-KC4

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For centuries, refrigeration tech has stayed the same — energy-hungry and reliant on harmful gases. Enter magnetocaloric cooling: a new solution claiming to be 30% more energy-efficient than current cooling systems. And it's scalable. From fridges to cooling buildings and server farms.

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cross-posted from: https://lemmy.world/post/27047758

I read Feynman lectures on physics Volume 1 Chapter 37 for the 2nd time. It has the best explanation of the 2-slits experiment for me. 1 of the factors behind my <3 for physics is how amazing the universe is. The wave-particle duality is so amazing.

Chapters 1–36 aren't prequisites for Chapter 37. You can read 37 at once.

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Global sea level rose faster than expected in 2024, mostly because of ocean water expanding as it warms, or thermal expansion. According to a NASA-led analysis, last year's rate of rise was 0.23 inches (0.59 centimeters) per year, compared to the expected rate of 0.17 inches (0.43 centimeters) per year.

"The rise we saw in 2024 was higher than we expected," said Josh Willis, a sea level researcher at NASA's Jet Propulsion Laboratory in Southern California. "Every year is a little bit different, but what's clear is that the ocean continues to rise, and the rate of rise is getting faster and faster."

In recent years, about two-thirds of sea level rise was from the addition of water from land into the ocean by melting ice sheets and glaciers. About a third came from thermal expansion of seawater. But in 2024, those contributions flipped, with two-thirds of sea level rise coming from thermal expansion.

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cross-posted from: https://lemmy.world/post/26503399

Posting here hoping for a physics-based reply.

I viewed a vid re power versus torque in vehicles. My understanding is that power is torque multiplied by angular velocity. Given an amount of power, a high-torque vehicle won't go very fast. A very fast vehicle won't tow a very massive load.

I related it to my little knowledge re stick shift. Gear 1 is used to move a stopped vehicle or for low speeds. Does gear 1 mean max torque and lowest angular velocity? I imagine you need a high torque to overcome static friction. Does gear 2 mean a dip in torque and a rise in angular velocity? Does the max gear mean lowest torque and max angular velocity? When I was young, a driver said one can carefully switch from gear 1 to 2 then 2 to 3 (and so on) on a wide road with very few surrounding vehicles. He said this was the way to increase the velocity and a high gear generally meant more fuel-efficient.

Please correct me if any of the above is wrong.

I googled. Here's what I read –

" 'Revolutions per minute' is how many revolutions the engine itself is making per minute. The gear ratios then translate revolutions of the engine into revolutions of your tires (more or less). Lower gear means lower tire revolutions per engine revolution, but also the tires are easier to turn.

"So when the car is going slower, meaning it requires more force to accelerate, you want lower gears. As the car speeds up, you need less force to go faster or maintain that speed, so you switch to a higher gear, sacrificing power for more efficient use of your engine."

I didn't ask an llm to avoid hallucinations.

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Scientists have made a leap forward in understanding the pattern and structure of turbulence — a natural phenomenon observed in fluids such as moving water, ocean currents, chemical reactions, blood flow, storm clouds, plumes of smoke and even the plasma of stars.

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Are Cats Actually Liquid? (www.scientificamerican.com)
submitted 4 months ago by [email protected] to c/[email protected]
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Measuring gravitational analogues of quantum phenomena could lead to high-precision measurement of gravitational forces, according to a theoretical proposal.

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Here's a little physics riddle. It's really meant as a moment of self-reflection for physics teachers (I invite you to compare what answers you'd give within Relativity Theory).

We're in the context of Newtonian mechanics.

There are three small bodies. In the inertial coordinate system (t, x, y, z), we know the following about the three bodies (at a given instant of time):

  • The first has mass 3 kg
  • The second has velocity (1, 0, 0) m/s
  • The third has momentum (2, 0, 0) kg⋅m/s

Now consider a new coordinate system (t', x', y', z') related to the first by the following transformation (a Galileian boost):

t' = t, x' = x - u⋅t, y' = y, z' = z with u = 1 m/s

Questions:

  • What is the mass of the first body in the new coordinate system?
  • What is the velocity of the second body in the new coordinate system?
  • What is the momentum of the third body in the new coordinate system?

Can you give definite answers to these three questions, and motivate your answers with simple physical principles? Note that by "definite answer" I don't necessarily mean an answer with a definite numerical value.

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cross-posted from: https://slrpnk.net/post/15007841

Eating gamma radiation for breakfast

Some fungal species appear to be able to use strong radiation as an energy source for growth. Tom Ireland explores the exciting potential of these understudied organisms

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In the heart of World War II, as the Nazis took control of Copenhagen, a peculiar situation took place at the Institute of Theoretical Physics, led by physicist Niels Bohr. Two Nobel laureates Max von Laue and James Franck, fearing the confiscation of their gold Nobel Prize medals by the Nazis, had sent their medals to Bohr for safekeeping.

On the day the Nazis arrived in Copenhagen, Hungarian chemist Georgy de Hevesy, who was working in Bohr's lab, devised a plan to prevent the discovery of the medals. Initially considering burying the medals, they quickly dismissed the idea, fearing the thorough searches the Nazis would conduct. Instead, de Hevesy proposed a chemical solution — literally. Utilizing a mixture known as "aqua regia" (a blend of hydrochloric and nitric acids), he set about dissolving the gold medals. This concoction is one of the few substances capable of dissolving gold, a notably unreactive element. As the Nazis marched outside, de Hevesy dissolved the precious medals, reducing them to a colorless solution that eventually turned bright orange. The liquid containing the dissolved gold was then placed on a high shelf in the laboratory, where it remained unnoticed throughout the Nazi occupation​.

Post World War II, upon returning to the laboratory after V-E Day, de Hevesy found the beaker undisturbed on the shelf. The gold was recovered from the solution and returned to the Nobel Prize committee, who then reminted the medals and presented them back to Laue and Franck in a ceremony in 1952.

Source: Fermat’s Library via LinkedIn

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