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 LIGO Back Online: Upgraded Detector to Spot Fainter Gravitational Waves
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High School Understanding Time Dilation: How Passing Photons Affect Time Measurement
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Undergrad Locally Inertial Frames: Freefall & Relative Velocities
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Undergrad Adler's New Book on Relativity: Misprint on Page 16?
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Undergrad A question about metric compatibility equation
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High School Time Dilation: Is This a Reasonable Explanation?
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High School Triplets Paradox: Is There a Solution?
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High School Perception of Velocity in Special Relativity
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High School How to Add Metres & Seconds for Equal ds2: Einstein's Theory
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Undergrad Why do strong fields complicate our understanding of singularities?
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Question About Text: Example 4.1 on Page 35-6
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Graduate Interior volume of a black hole
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Undergrad Schwarzschild Geometry: Einstein Tensor & Mass Density
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Undergrad How fast does the particle go through spacetime?
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High School What is the metric for a bag-of-gold spacetime?
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High School How do Black Holes Grow? A Far-Away Observer's Perspective
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Undergrad Inertial Gravity in Relativistic Geodesics - Forum Discussion
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High School Do Gravitational Forces Increase for Objects Moving at Light Speed?
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High School Speed of Light Reflection: Einstein's Train & Mirrors
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High School Does Gravitation Start at Black Hole Event Horizon?
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Graduate Origin of BH Entropy & Info Missing Puzzle Resolution
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Undergrad Numerical Solution of Complex Systems in GR
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Undergrad Sabine Hossenfelder says time dilation is due to acceleration
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Undergrad What is the velocity of a photon through the four dimensions?
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Undergrad Escape from Two Black Holes? Solve the Mystery!
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Graduate Why can't we say that photon has very very small mass?
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Graduate Minkowski Spacetime 3+1 Dimensions: Conformal Diagram w/Boundary
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Graduate GW Binary Merger: Riemann Tensor in Source & TT-Gauge
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Graduate Special & General Relativity: CTC Metrics in Cylindrical Coordinates
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High School A Scenic Trip as a Spaceship at 0.999...c, and questions that arise
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High School The synchronization of clocks and the relativity of motion
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Undergrad Time Paradox: A & B's Clocks Move Differently
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Undergrad Worldline Curve vs Trajectory: What’s the Difference?
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High School Black Holes: How Do They Move?
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High School Four Velocity Sign of Time: \dot t>0?
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Graduate Hyperplanes of Simultaneity and BigBang
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Undergrad Universe Expansion: GR vs Hubble Reconciled
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High School Is Time Dilation About Particle Motion Rather Than Time Itself?
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Graduate Solving Geodesics with Metric $$ds^2$$
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Undergrad Can worldlines exist that defy traditional spacetime classifications?
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High School FRB & Gravitational Wave Link: Scientists Baffled
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Undergrad Black holes to explode due to evaporation?
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Undergrad Do objects gain mass while approaching light speed?
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Insights Why There Are Maximum Mass Limits for Compact Objects
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Undergrad Kerr & Nordström Black Hole Evaporation: Q&A
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High School Explaining Distant Time Dilation & Enhanced Gravitation
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High School Is Einstein's Space-Time Theory Overfitted or Simply a Visualization Tool?
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High School The Effect of Binding Energy on Mass
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Undergrad Observed Redshift from Moving Source: Deriving the Result
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Undergrad Gravitational Field Transformations Under Boosted Velocity
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Undergrad Light-Like Separation: Is It Possible?
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High School Explaining Galaxy Rotation Speed Discrepancies with GR & Gravitic Fields
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Undergrad How to obtain other inverse metrics than that of Schwarzschild?
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High School Block universe theory question
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Undergrad Has anyone measured the speed of light in one direction?
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High School Spagettification and a singularity
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High School The twin paradox and black holes
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Undergrad Dark Energy Strength in Great Voids of Galaxies
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Graduate Solving "const. K" in Gourgoulhon's SR in General Frames
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High School Questions on the Michelson Morley Experiment
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Undergrad Gravitational Field Existence in Void: Philosophical Inquiry
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Graduate How Does Linear Framedragging Affect Parallel Moving Masses in Flat Spacetime?
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Undergrad Relativity & Simultaneity Convention: Meaning & Impact
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High School Phase Change in Light: A & B Signal Reflections
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High School Why Don't We Live Inside a Black Hole?
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Undergrad Circular Orbit in Schwarzschild: Orbital Period
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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 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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