Special and General Relativity Forum

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Join in expert discussion on special and general relativity discussion. Relativity is the dependence of various physical phenomena on relative motion of the observer and the observed objects.
I Self-Study General Relativity: After Multivariate Calc in HS
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B Paradox of Simultaneous Flashing in a Moving Triangle of Lights
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B How can two ships pass each other twice at the same moment?
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B Mass Reduction in Combustion: Real or Myth?
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I Speed of Sound & Light: Is it True?
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B Contradictory time dilation equations
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I Is Teleportation & Time Travel Possible?
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I What software can I use to make space-time diagrams?
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I Riemann Curvature Tensor on 2D Sphere: Surprising Results
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B E & B Field Oscillation with Time Dilation: Explained
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I Does time dilation cause different aging rates for people?
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I Precession of Mercury: Adaptation for Observers
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I Thought Exp: Gen Relativity & Time Dilation
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B Twin Paradox: Radioactive Decay Tested
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I Velocity Addition and Doppler Effect: Explained
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B How to derive the continuity equation for a perfect fluid?
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B First Experimental Confirmation of GR
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I Are Derivatives of the Metric Different in Flat Spacetime?
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I Magnetic Field Generated By Moving Charged Objects - Confusion Explained
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I Dissolving Event Horizon w/Charged & Rotating BH
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B Time Travel Possibility with Two Black Holes Orbiting Each Other
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B Experimental Confirmation Length Contraction Velocity Addition
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B Why can't energy or information go faster than light?
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B General Relativity and the curvature of space: more space or less than flat?
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I Const Curvature Scalar & 3-Torus: Is It Maximally Symmetric?
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B Relativistic Photon Mass: Can It Exist?
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I Explore Alternative Interpretations of Special Relativity
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I Einstein Field Eqns: East/West Coast Metrics
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I Understanding Feynman's Relativistic Electric Field Equation
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I Explaining the Twin Paradox: A Big Problem?
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I Is it feasible to measure one way speed of light this way?
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A Levi-Civita Connection & Length of Curves in GR
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I How to Change Between Unit Systems w/ ##c \ne 1, \hbar \ne 1, G \ne 1##
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B Twin Paradox: Tom & Jerry Agree on Clock Time But Who is Older?
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B Einstein's Universe (1979) - Nigel Calder, Peter Ustinov
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B Transform to accelerating coordinates
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A Gravity Theories: GR vs Alternatives - Post 2018
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B Visualize 2D Intrinsic Curvature of Spacetime (1s+1t) in 3D
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I Momentum Conservation in Special Relativity: mwu
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I Inverting the metric coefficients in the Schwarzschild line element
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I Proper time to reach the singularity of a Schwarschild black hole
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I Time Dilation & Superluminal Travel: 2 Questions
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I Why does an object initially at rest begin to fall?
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I Does Light Curve Spacetime?
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B Doubt about the relativity of simultaneity
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I Interpreting Schwarzschild Metric: Photon Falls Toward Black Hole
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I Charged Particle Free Fall in Grav Field: Does Anyone Know Answer?
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B Why and how does the frequency of a moving clock affect its ticking speed?
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A Find 2D Geometry of Line Element in Coordinates
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B Where Does Momentum Go Near Merging Black Holes?
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Insights Does the Block Universe of Physics Mean Time is an Illusion?
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A Covering Group of SO(g) & Understanding Spinors on Curved Spacetime
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B Lagrangian Point in General Relativity
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B Looking Out of the Window: Phys & Math Meaning in Postulates & Principles
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B Shape of Hubble sphere at relativistic velocity
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B Can someone please explain Feynman's index notation?
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B Are time and light at the same speed?
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I Video camera in a moving rocket
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Block Universe Theory: Implications & Multiverse
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I Gravitons Replacing General Relativity: Can it Work?
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B Do we feel the Earth going around the Sun as acceleration?
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A Determining Geometry of Line Element: A General Method?
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B Light Behaviour at High Speed: Explained
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B Paradox about black hole evaporation
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I Is it possible to extend Newtonian gravity to include energy as well as mass?
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A Black Holes & White Holes: Same or Different?
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I Temporal Gradients at Event Horizons of Black Holes
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I Electrodynamics of Dielectrics: 4D to 3D
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B Bob & Ted See Different Ages for Alice on Earth
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I The Speed of Light: Can it Travel in Opposite Directions?
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I EM Field Strength in Curved Spacetime: Is it Unchanged?
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B Why is the speed of light constant?
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I The center of mass & relativistic collisions
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I Q re de Sitter–Schwarzschild metric
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I How Does Relativity of Simultaneity Clash w/Thermodynamics?
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I Special Relativity: Intuition & Quantities Explained
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I Check for geodesically-followed path in a coordinate-free way
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I Logic question on relativity- no math
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I Riemann Tensor, Stoke's Theorem & Winding Number
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B Understanding Strong Equivalence Principle Errors & Misunderstandings
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I Finite Lorentz Transformation via Poisson Bracket
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I Special Relativity & Non-Instantaneous Force Equations
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A Axisymmetric vs Spherical Metric Comparison
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B Particle Horizon & Coformal Time Near c - Observer Effects
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I Gravity transition directly at the underside of a "shell planet"
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I Another spacetime visualization
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I Variation of Ricci scalar wrt derivative of metric
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I Acceleration in Special Relativity
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B Twin paradox explained for laymen
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B Black hole horizon and Hawking evaporation
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A Parallel plate capacitor in the Rindler metric
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I Can Newtonian Gravity be Thought of as a Theory of Curved Time?
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I Geodesics using 2 Variables: Time & Radius from Mass
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I Speed of light for a Rindler observer
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B Special Cases of Stress-Energy Tensor in GR
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I Do you accelerate through time when you stand still on Earth?
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B Shankar on Lorentz Transformation: Does x' = ct'?
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I What initiates gravitational movement?
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I Mercury Perihelion Precession: Analytic Derivation
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I Deriving vacuum FRW equations directly from action
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