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 Twin Paradox (3 objects version)
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Undergrad Calculating Particle Redshift at Time t_0 & t_1
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Undergrad The Derivative Nature of Time and Its Relation to Earth's Rotation and Speed
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Undergrad Follow Up on M. LeBellac & J.M. Levy-Leblond's "Galilean Electromagnetism
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Graduate What assumptions underly the Lorentz transformation?
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Undergrad How is proper time visualized in the FLRW metric's 4D spacetime geometry?
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Undergrad Only Minkowski or Galilei from Commutative Velocity Composition
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Undergrad Gravity Wave Speed: Deriving Constancy from Maxwell Eqs.
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Undergrad Understanding Covariant and Partial Derivatives in General Relativity
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Undergrad Lorentz Transformation Derivation: Assumptions Req'd?
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High School Calculating Time Dilation w/ Light Clock - Implications & Mistakes?
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High School Cosmic Inflation & Censorship: Validation or Corrections?
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Undergrad What Happens Inside BH Event Horizon?
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Undergrad Calculating Relative Change in Travel Time Due to Spacetime Perturbation
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Undergrad Please help with my spacetime diagrams (relativity problem)
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High School Time: What We Read On The Clock?
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Undergrad Diagonal Matrix of Stress-Energy Tensor: Why?
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Undergrad Why Does Covariant Index Represent Partial Derivative in Special Relativity?
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Undergrad Conserved Quantity Along Affine Parameter
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Undergrad Light Clock Relativity: Why Divide T_moving/T_stationary?
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Undergrad Question about Stress-Energy Tensor: A First Course in GR
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Graduate Is Gravity Just the Electrostatic Force?
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High School Can Particles Escape a Black Hole? The Hawking Radiation Improbability
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Undergrad Uniform gravitational field possible in GR?
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Graduate Connectedness of Boundary Points in Schwarzschild Penrose Chart
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Undergrad Why do we still say “the speed of light” instead of “c”?
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Undergrad Definition of "Physical Frame": All You Need To Know
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Undergrad Is the concept of a one-way speed of light meaningful and measurable?
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High School Object Weight on Magnetar vs Neutron Star: Attract or Repel?
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Graduate Special Relativity Fiber Bundle: R^3 & Lorentz Metric
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Undergrad Speed of Light: Spaceship & Gravity Law Impact
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Undergrad Why is Number-Flux Four-Vector Frame-Independent?
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Undergrad Velocity addition via k-calculus
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High School Penrose Diag Black Hole: Riddle Me This
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Undergrad The Length of World Line: Prerequisite for Proper Time
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Graduate Britgrav Weyl Tensor Research: Find Paper Authors, Title & Accessibility
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Undergrad Why Is Minkowski Spacetime Non-Euclidean?
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Undergrad Weak principle of equivalence (Galileo, Newton)
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High School Does Mass Have Lasting Gravitational Effect Over Time?
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Undergrad The Theoretical Minimum: Length Contraction and Time Dilation
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Graduate Units of Kerr Understanding Mass & Angular Momentum
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High School Free Fall in Curved Spacetime: Does Minkowski Spacetime Exist?
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Undergrad Searching for "Why Is Minkowski Spacetime Non-Euclidean" by Cronkhite
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Undergrad Constraints on Lorentz Velocity Transformation
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Undergrad Does Space Curvature Account for Gravity Between Individual Atoms?
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Undergrad Can Maxwell's Equations Explain Gravitation Through Retarded Wave Solutions?
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Graduate Schwarzschild Geometry: Evaluating Proper Distance
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High School Orthogonality in Minkowski Spacetime: Meaning & Visualization
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Undergrad Co-Moving Coordinates & Lapse Function N(t) in ADM Decomposition
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Undergrad Will a spherical mass be set in motion by a spherical shell rotating around it?
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High School Proving Reciprocity Of Time Dilation
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Undergrad Applying Velocity Addition in Rotating Frame: Is It Correct?
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Undergrad Shape Dynamics: How Can It Offer Same Predictions as GR & SR?
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Undergrad Questions concerning the geometry of spacetime
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High School Can Black Hole Gravity Be Overpowered?
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Undergrad Relativistic Velocity Addition: Calculating Electron Speed
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Undergrad Does the Light's One/Two-Way Speed Distinction Mean Anything?
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Undergrad Calculate Eigenvalues of Electromagnetic & Stress-Energy Tensors
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Graduate Worked examples Cartan Formalism
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Graduate Relativistic Hydrodynamics Eqn for Perfect Fluid: Insight Needed
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Undergrad Why am I getting the wrong conclusion from my spacetime diagram?
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Undergrad Instrument Size & Wavelength: What's the Relationship?
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Undergrad Raising & Lowering Indices: Q&A on Relativity
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High School Can a Planet Made of Glass Generate Free Energy?
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Undergrad Potential Energy in Wormholes: Charged Particles & Electric Fields
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High School Sagnac effect for matter beams
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Undergrad Is the Killer Crate Paradox Resolved?
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Undergrad Doppler Analysis of Twin Experiment: Valid Argument?
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Undergrad How Can Outward Normal Vector Point Inwards?
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Undergrad Einstein Definition of Simultaneity for Langevin Observers
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Undergrad Infinite Frequencies & Extraterrestrial Signals: What Are We Missing?
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Undergrad The Units of the Cosmological Constant: eV^2
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Undergrad Simulating GR: Worth the Effort?
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Undergrad Fermi-Walker Transport: History & 1932 Paper
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High School Time Dilation & Muon De Broglie Wavelength: Explained
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High School What Does Hawking Mean by Negative Energy at the Big Bang?
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High School Parallel light reflection for a one-way speed of light measurement setup
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Undergrad Kronecker Delta: Order of Indices Explained
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High School Travel 7 Light Years at 50000km/s - How Long?
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Undergrad Is Time Dilation Just a Misunderstanding of Clock Errors?
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High School Time Dilation on Rotating Disk: Clocks on Disk Perspective
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High School General Relativity & Ether: Clarifying a Contradiction?
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Graduate Curvature & Connection Without Metric
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Undergrad Energy Density in E Field: Does it Contribute to Inertial Mass?
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Undergrad Physical meaning of a spacelike geodesic
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Graduate Can a conformal flat metric be curved?
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Undergrad Radiate Single Charged Particle: Free Fall in Black Hole?
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Undergrad Distance Contraction: Is D or D*sqrt(1-(v/c)^2) Traveled?
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Insights Rindler Motion in Special Relativity: Hyperbolic Trajectories - Comments
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Graduate Generalize Special Relativity for Flat Spacetime
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Undergrad Gravitoelectromagnetism: Why Equation Differs in Sources
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Graduate Affine Spaces and Vector Spaces
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High School Gravitational Time Dilation on Mountaintops: New Member Questions
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High School Length, Time, and Velocity -- Which are fundamental quantities?
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Undergrad Effects of Supermassive Black Hole Merger on Nearby Bodies
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Undergrad Is Acceleration an Invariant? (Taylor & Wheeler)
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Undergrad Cat Chasing Red Dot Faster Than c: Results & Analysis
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Undergrad Difference between proper time and coordinate time
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Undergrad Length contraction in General Relativity
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Graduate Wald's Abstract Index Notation: Explaining T^{acde}_b
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