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.
High School Measuring the One Way Speed of Light
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High School On the four dimensions of special relativity
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High School Understanding the Relationship Between c and c2 in the Famous Formula e = mc2
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Undergrad Cosmic Censorship: Does it Hold?
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Graduate Understanding Kerr Black Holes: Metric, Killing Vectors & Event Horizons
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Graduate Temp of Moving Body: 110 Yrs of Debate | Current Tech Update?
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High School Explaining Spaghettification w/ Spacetime Curvature
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Undergrad What is the Role of Matter in General Relativity's Lagrangian?
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Graduate Understanding Tensor Notation: What is the Difference?
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Undergrad Relativistic Velocity, Perp. Accel., Momentum: Explained
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High School A few questions about the covariant derivative
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Undergrad Gravity: Compounded Space (Time) Signal?
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Graduate Geodesic Eq Derived from Einstein Field Equations?
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Undergrad Disappearing Sun: A Thought Experiment on the Effects of Gravity and Light
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Undergrad Conservation of energy in general relativity
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Undergrad Recovering Newton's energy conservation law for an Earth's lab
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Undergrad Is coordinate speed affected by gravitational waves?
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Undergrad Hawking Radiation: Info vs Semanticity? - Hossenfelder
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Undergrad Spacetime invariance algebraic proof
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Graduate The g_ij as potentials for the gravitational field
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Undergrad The Sub Photon Sphere Escape Game
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Undergrad Unravelling the Mysteries of the Kerr Black Hole Ergosphere
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Undergrad Radius Excess of Curvature in Relativity: Explained
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High School Understanding the active/passive transformation of a scalar field
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High School Light Clock: Why Aren't Delta T and 2D/c Equal?
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Undergrad Investigating The Photon Sphere
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Undergrad Solving Relativistic Inelastic Collisions: 150 GeV Energy
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High School Transforming the Electric Field Measured by an Observer with 4-velocity U
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Undergrad Solving the Spherically Symmetric Einstein Equation
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High School Gravitational Wave System and Locations
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High School Who Won the 2020 Nobel Prize in Physics and What Did They Discover?
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High School Value of this 'Science' Channel as quick intro
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Undergrad Observing Black Holes in Finite Time
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Undergrad Self-Study General Relativity: After Multivariate Calc in HS
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High School Paradox of Simultaneous Flashing in a Moving Triangle of Lights
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High School How can two ships pass each other twice at the same moment?
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High School Mass Reduction in Combustion: Real or Myth?
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Undergrad Speed of Sound & Light: Is it True?
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High School Contradictory time dilation equations
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Undergrad Is Teleportation & Time Travel Possible?
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Undergrad What software can I use to make space-time diagrams?
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Undergrad Riemann Curvature Tensor on 2D Sphere: Surprising Results
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High School Event horizon for observer within main horizon
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High School E & B Field Oscillation with Time Dilation: Explained
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Undergrad Does time dilation cause different aging rates for people?
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Undergrad Precession of Mercury: Adaptation for Observers
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Undergrad How to communicate between planets?
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Undergrad Thought Exp: Gen Relativity & Time Dilation
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High School Twin Paradox: Radioactive Decay Tested
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Undergrad Velocity Addition and Doppler Effect: Explained
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High School How to derive the continuity equation for a perfect fluid?
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High School First Experimental Confirmation of GR
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Undergrad Are Derivatives of the Metric Different in Flat Spacetime?
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Undergrad Magnetic Field Generated By Moving Charged Objects - Confusion Explained
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Undergrad Dissolving Event Horizon w/Charged & Rotating BH
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High School Time Travel Possibility with Two Black Holes Orbiting Each Other
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High School Experimental Confirmation Length Contraction Velocity Addition
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High School Why can't energy or information go faster than light?
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High School General Relativity and the curvature of space: more space or less than flat?
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Undergrad Const Curvature Scalar & 3-Torus: Is It Maximally Symmetric?
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High School Relativistic Photon Mass: Can It Exist?
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Undergrad Explore Alternative Interpretations of Special Relativity
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Undergrad Einstein Field Eqns: East/West Coast Metrics
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Undergrad Understanding Feynman's Relativistic Electric Field Equation
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Undergrad Explaining the Twin Paradox: A Big Problem?
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Undergrad Is it feasible to measure one way speed of light this way?
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Graduate Levi-Civita Connection & Length of Curves in GR
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Undergrad How to Change Between Unit Systems w/ ##c \ne 1, \hbar \ne 1, G \ne 1##
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High School Twin Paradox: Tom & Jerry Agree on Clock Time But Who is Older?
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High School Einstein's Universe (1979) - Nigel Calder, Peter Ustinov
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High School Transform to accelerating coordinates
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Graduate Gravity Theories: GR vs Alternatives - Post 2018
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High School Visualize 2D Intrinsic Curvature of Spacetime (1s+1t) in 3D
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Undergrad Momentum Conservation in Special Relativity: mwu
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Undergrad Inverting the metric coefficients in the Schwarzschild line element
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Undergrad Proper time to reach the singularity of a Schwarschild black hole
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Undergrad Time Dilation & Superluminal Travel: 2 Questions
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Undergrad Why does an object initially at rest begin to fall?
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Undergrad Does Light Curve Spacetime?
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High School Doubt about the relativity of simultaneity
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Undergrad Interpreting Schwarzschild Metric: Photon Falls Toward Black Hole
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Undergrad Charged Particle Free Fall in Grav Field: Does Anyone Know Answer?
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High School Why and how does the frequency of a moving clock affect its ticking speed?
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Graduate Find 2D Geometry of Line Element in Coordinates
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High School 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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Graduate Covering Group of SO(g) & Understanding Spinors on Curved Spacetime
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High School Lagrangian Point in General Relativity
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High School Looking Out of the Window: Phys & Math Meaning in Postulates & Principles
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High School Shape of Hubble sphere at relativistic velocity
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High School Can someone please explain Feynman's index notation?
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High School Are time and light at the same speed?
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Undergrad Video camera in a moving rocket
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Graduate Block Universe Theory: Implications & Multiverse
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Undergrad Gravitons Replacing General Relativity: Can it Work?
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High School Do we feel the Earth going around the Sun as acceleration?
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Graduate Determining Geometry of Line Element: A General Method?
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High School Light Behaviour at High Speed: Explained
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High School Paradox about black hole evaporation
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Undergrad Is it possible to extend Newtonian gravity to include energy as well as mass?
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