X_PINE Arrow Physics’ Post

I'm looking forward to spending some time with these notes on the symplectic geometry of the ’three body problem.’ After the first twenty pages I like where this is headed already, and eventually it gets into some practical low-energy near-primary computation techniques applicable to satellites or orbital transfers. Back in 2018 or so I discovered Ed Belbruno's work on ballistic capture and ultra-low Δv orbital transfers using chaotic boundaries between stability basins. It was such a beautiful application of dynamical systems theory that I've been hooked on this subject ever since. The fact that it has practical application to something as intrinsically thrilling as navigating the solar system's ‘gravitational transit network’ certainly doesn't hurt either. Nobody's ever gonna make money mining asteroids (far less colonize the solar system) unless we figure out how to economically move lots of heavy and locally precious stuff like water and metals around―for commodities like these, decades long transit times via the ‘interplanetary tubes’ can be reasonably planned for in mission designs and capital structures (it's literally what futures were invented for, albeit not exactly on this time scale). If you're willing to wait for gravity to do the work for you, you can take advantage of ultra-low Δv to slash the requirements for propellant mass and high-thrust, low-specific impulse engines otherwise required to change the orbit of the payload. #appliedmathematics #physics #spaceflight P.S.: I have no idea how we're gonna make plastic in space, and that seems like pretty fundamental technical requirement for establishing a self-sufficient technological manufacturing base away from Earth, let alone permanent human settlements. It would be hilariously ironic if plastic ends up being the most valuable commodity exported from Earth. Either that or figure out how to deal with Titan's hydrocarbons… Yet another reason why it's better to go to Titan than to go to Mars. There's no reason to go Mars aside from planting a flag and taking pictures―ahem―conducting science.

#JustPublished "Modelling the mechanical behaviour of clay using particle‑scale simulations" in Granular Matter 26(29) 2024 Paper by Dr John de Bono and Prof. Glenn McDowell of Nottingham Centre for Geomechanics (NCG) - This paper demonstrates the latest developments in particle-scale modelling of a clay - It shows that by creating an initial sample of platelets featuring aggregated stacks, excellent macroscopic behaviour is achieved - This approach is justified by examining SEM images of clay slurries, and is consistent with the behaviour of real clays - The use of aggregated stacks allows a wider range of platelet interactions and micro properties to be simulated and investigated, and significantly, enables interactions to be modelled that are based on a range of real measurements obtained from surface force experiments Paper available: https://lnkd.in/di3bKsQz #Clay #DEM #Kaolinite #NumericalModelling #ParticleScaleModelling

A hull speed is a different hydrodynamic concept and stems from the complex physics of the interplay of the vessel with the surrounding water medium. Check out this article 👉 #HullSpeed #Shipping #Maritime #MarineInsight #Merchantnavy #Merchantmarine #MerchantnavyShips

It is a great pleasure for me to share our new work with Connor Roberts, Gunnar Pruessner, Sébastien Guenneau, Ziluo Zhang (Imperial College London), Stefano Bo (King's College London) and Carlos Escudero (UNED - Universidad Nacional de Educación a Distancia (Spain)) on "Stochastic cloaking: concealing a region from diffusive particles" In this paper, we present a novel class of cloaking in which a region of space is concealed from an ensemble of diffusing particles whose individual trajectories are governed by a stochastic (Langevin) equation. In particular, we simulate how different interpretations of the Langevin equation affect the cloaking performance of an annular single-layer invisibility cloak of smoothly varying diffusivity in two dimensions. Near-perfect cloaking is achieved under the Ito convention, indicated by the cloak preventing particles from accessing an inner core while simultaneously preserving the particle density outside the cloak relative to simulations involving no protected region (and no cloak). Even better cloaking performance can be achieved by regularizing the singular behavior of the cloak -- which we demonstrate through two different approaches. These results establish the foundations of ``stochastic cloaking'', which we believe to be a significant milestone following that of optical and thermal cloaking. #stochasticprocess #statisticalmechanics #inivisibility #cloaking

Refraction is the bending of light when it passes from one medium to another, like from air to water. This happens because light changes speed as it moves between different substances. Check out this fascinating video that visually explains the concept of refraction using a glass of water and arrows. Watch how light bends when it passes through different mediums, making the lower arrow appear reversed. #Physics #ScienceExplained #Refraction #Optics #LightBending #EducationalVideo

#Wormholes aka 'Einstein Rosen-bridges' are still 'stuck in physics' (https://lnkd.in/e_qCn5wN) and another 'physics' theory than can be retired. #UFOs/#UAPs/#CTPcraft do NOT use #wormholes for FTL travel. C-MANIFOLDS OF C-DOMAIN If anything the correct term would be a C-manifold of C-domain. The #UFO/#UAP/#CTPcraft doesn't 'create' a C-manifold (as they rather 'exist' in the background of reality). Group C-energy Frequency (GCF) of a physical location already exists. C-manifolds are sort of 'activated' when the pilot of a #CTPcraft initiates C-energy Frequency Modulation (CeFM) as shown here. (https://lnkd.in/eveiPr9c) or the 'phase-out' or the 'dematerialization' observed. #CTPcraft remains intact, however, two additional Fundamental Forces are being called in via the CTP Energy Cycle. CeFM/FTL space travel requires 2 additional Fundamental Forces not accounted for. WHAT DO WE NOTICE: NO WORMHOLE CREATED (https://lnkd.in/eveiPr9c) Notice: THERE IS NO #WORMHOLE! or 'tubule-opening' or 'tubule-structure' (like a #wormhole) that is being created at all. Because #CTPcraft do NOT use wormholes for FTL travel. T-energy 'codes' the physical hull of a #CTPcraft to a new destination via C-domain within mere moments: no limitations of spatial distances. #wormholes are yet ANOTHER outdated physics theory that can thrown out. (https://lnkd.in/eCBsazCZ) all of this - outdated by new disruptive CTPSci Sciences. #newscience #fasterthanlight #spacetravel #spaceexploration #futurespace

In this work, we study a hypersurface immersed in specific types of cylindrically symmetric static space-times, then we identify the gauge fields of the Lagrangian that minimizes the area besides the Noether symmetries. We show that these symmetries are part of the Killing algebra of cylindrically symmetric static space-times. By using Noether's theorem, we construct the conserved vector fields for the minimal hypersurface. Paper ➡️ https://lnkd.in/dVTnTPqF #Research

🚀#mdpisymmetry #EditorsChoice Excited to share an Editor's Choice Paper with you. "The Stability of a Hydrodynamic Bravais Lattice" 🔸https://lnkd.in/ey-R69Dm 🔹Authors: Miles Couchman, Davis Evans and John W. M. Bush University of Cambridge Massachusetts Institute of Technology 🔸Abstract: We present the results of a theoretical investigation of the stability and collective vibrations of a two-dimensional hydrodynamic lattice comprised of millimetric droplets bouncing on the surface of a vibrating liquid bath. We derive the linearized equations of motion describing the dynamics of a generic Bravais lattice, as encompasses all possible tilings of parallelograms in an infinite plane-filling array... #hydrodynamic #phonons Physics Section of Symmetry

You are probably already familiar with the meaning of mechanics and its various branches. Some of the fundamental concepts in the study of mechanics are space, mass, time and force. What is the meaning of each of these terms? How are they referenced in the study of mechanics? Watch this and share with a friend: https://lnkd.in/eBXRuj_t

Pleased to share my latest paper entitled "An Experimental and Numerical Study of Layered Sandstone's Anisotropic Behaviour Under Compressive and Tensile Stress Conditions" published in Rock Mechanics and Rock Engineering (Q1, H-Index=136, SJR=1.9). https://lnkd.in/dzpwynUD #Sandstone #Bedding #Anisotropy #PFC2D #Smooth_joint_model #Failure_mode