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.
Undergrad Explore Spacetimes, Metrics & Symmetries in Relativity Theory
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Graduate Understanding killing vectors and transformations of metric
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High School Is Brian or Jim Wrong? (the science of Dr. Who)
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High School Mick's Spooky Time Dilation Puzzle
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Graduate Landau's Maximum Mass Limit Derivation in Shapiro & Teukolsky (1983)
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Graduate Motivation for Theta = Pi/2 on Wald GR p138
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Undergrad Error in Concepts: Intro to Mechanics Kolenkow & Kleppner
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Undergrad Can Crafts Reach 2c Relative to Me?
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High School What limits the speed of a gravitational wave to c?
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High School Relativity of Measures: A vs B Frame & Light Source S
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High School Mechanics behind curved time causing gravitation/geodesics
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High School Speed of light and this Accelerating Rocket scenario
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Undergrad No Symmetry Spacetimes/Metrics in Theory of Relativity
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Undergrad Twin Paradox: Aging Slower with Continuous Acceleration?
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High School Cherenkov Radiation -- How does this not break causality?
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Undergrad Derivation of SR's time-dilatation in 1d?
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Undergrad What Is the Geometrical Meaning of Principal Null Directions?
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Graduate Proper Volume on Constant Hypersurface in Alcubierre Metric
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High School Where does the energy of gravity come from?
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Undergrad Schwarzschild in Cartesian: Tricks for Transformation
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Undergrad Differentiate w/ Respect to Affine Parameter
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Undergrad Understanding Einstein's second postulate of special relativity
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High School Calculating Fuel Efficiency of Rocket Going Near c
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Undergrad Solving Paradox: Man Running with Pole Reaches Door Before Button is Pressed
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Undergrad Lack of Symmetry in X & T: Explained for Beginners
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Undergrad Can time be another basis vector under Galilean relativity?
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Undergrad Mainstream interpretation of Newton's bucket argument?
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Undergrad Black Holes: Event Horizon Causally Disconnected?
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Undergrad Solving Spherically Symmetric Static Star Equations of Motion
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Graduate Dirac's Conservation of Matter: A Closer Look
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Undergrad Time dilatopause for black holes
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Graduate Get GR Tensor II: Where to Buy Program Library
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High School How do we identify a stationary system?
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High School A thought experiment of the relativity of light
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Undergrad Doppler Effect on Light: Constant Speed of Light Confusion
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Undergrad Time Dilation Paradox: Geosynchronous Satellites
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Graduate Why are General relativity texts so much more formal?
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Undergrad How to rule out that the speed of light was different in the past?
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High School Find Geodesics in Dynamic Ellis Orbits Metric
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Undergrad How meaningful is the notion of now here on Earth?
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Graduate Going from Cauchy Stress Tensor to GR's Energy Momentum Tensor
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Undergrad Effects of time dilation for near-speed-of-light travel
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Undergrad Orbital Precession Calculation: Unit Explained
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Undergrad Can Vacuum Energy Alter Our Understanding of Gravity?
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High School Proposed Experiment - Speed of Light
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Graduate Popular Pseudoscience Video on General Relativity: Analysis & Criticism
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Graduate Can an Oscillating Eternal Universe be Described without Singularity?
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Graduate Cosmological Density Perturbation vs Homogeneity: Questions Answered
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High School Spaghettification & Black Holes: Classical & Einsteinian
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High School Does General Relativity Really Support Nonlocality?
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High School Questions about the Speed of Light, Time, etc.
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Undergrad Proof of Lorentz Gauge Existence: Help Understanding Schutz 8.3
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Undergrad Modeling the Earth and Sun (2 body orbits) using general relativity?
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Graduate Small and large extra dimension(s) of the physical space
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High School Calc Excess Rad on Earth in Curved 3D Space | Feynman Lectures 6-2
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Undergrad Does Special Relativity Change Our Perception of Others?
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Undergrad Conservation of Energy in GR: A-B System Analysis
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High School Time Travel: Can Humans Go Faster Than Ordinary Speed?
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Undergrad Light in an accelerated elevator
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Insights Oppenheimer-Snyder Model of Gravitational Collapse: Implications
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High School Derivation of time dilation without light clocks
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Undergrad Muon Decay Example from Morin's Book: Issues Explained
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Undergrad Gravity of the Sun: Einstein's Calculation and Beyond
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Undergrad Why Are the Two Diagrams in the Twin Paradox Not Symmetric?
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High School Relativity & Gravity: Resolving the Discrepancy
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Graduate Two degrees of freedom in GR after boundary conditions specified?
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Undergrad Train Simulation: Observer A and B Contradiction?
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High School Light Speed In Forward and Backward Directions
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Undergrad Visualising Torsion Tensor: Is There a Picture?
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Undergrad Special Relativity philosophy and anxiety
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Undergrad Physics Error in Larry Niven's "Neutron Star
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High School Can Matter Enter a Black Hole Intact? Debate & Advice
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Undergrad Contracting the stress energy tensor
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Graduate Oppenheimer-Snyder Model of Gravitational Collapse: Mathematical Details
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Undergrad Gravitation Machine Invented? Research Idea
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Graduate Do Astrophysical Black Holes Contain CTCs?
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High School Speed of Light Unaffected by Moving Emitter
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Undergrad How do angular displacement and rapidity relate in special relativity?
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Undergrad Time Dilation & Aging: Why Do Astronauts Age More Slowly in Space?
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Undergrad How can time only have one direction?
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Insights Oppenheimer-Snyder Model: Overview of Gravitational Collapse
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Graduate Static Gravitational Field: Why Must ##g_{m0} = 0##?
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High School Can there be time without mass?
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High School What if a needle hits Jupiter at nearly speed of light?
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Undergrad From Einstein Summation to Matrix Notation: Why?
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Undergrad Calculate Length Contraction for Accelerated Motion to Proxima Centauri
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High School My paraphrased explanation of the Twin Paradox
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Undergrad SR vs GR: Logical Necessity of Signal Propagation
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Graduate Two Questions about Novikov Coordinates
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Undergrad Arguments leading to the speed of light as a dimensionless constant
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High School Eddington Exp vs Newton: Comparing Starlight Deflection
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Undergrad Best Derivation of E=mc^2 - Fdx = V^2 dm
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High School The One-Way Speed of Light: Speculation of a Tired Mind
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Undergrad Need to resort to spherical wavefront to derive the LTs?
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Undergrad Charge conservation and special relativity
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High School Could Traveling at Near-Light Speed Create Black Holes?
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Graduate Decomposing Rank-2 Tensors in Dirac's "General Theory of Relativity
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Graduate Differential Forms Integration Exercise
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Undergrad Doppler Shift & Christoffel Symbols Issues
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High School Deep Space Speed Limit: What Prevents Exceeding Light Speed?
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