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 Is Acceleration an Invariant? (Taylor & Wheeler)
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I Cat Chasing Red Dot Faster Than c: Results & Analysis
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I Difference between proper time and coordinate time
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I Length contraction in General Relativity
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A Wald's Abstract Index Notation: Explaining T^{acde}_b
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I Spacetime Curvature via Triangle
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I Defining the components of a metric
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B Simple reasoning that the equivalence principle suggests curvature
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B Build a Time Dilation Clock for 8th Grade Science Project
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I Wilbert Zweistein's Objection to Equivalence Principle
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I Index Gymnastics: Tensor Product of 4-Vectors & Tensors
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I Can a Basis Vector be Lightlike?
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I Can time run backwards in an accelerating frame?
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B Ride Gravitational Waves to Increase Speed?
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A Proving $g(u,v)≠0$ with Linear Independence
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B Does this thought experiment show that Space must be curved?
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I Differences b/w Schwarzschild Radius & Event Horizon
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I Schwarzschild Metric & Particle Absorption
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I Rindler Wedge: Timelike or Spacelike? Intuition & Light Cone
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I Energy conditions and non-physical phenomena
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B Black Hole Event Horizon: Atom Effects & Wave Detection
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B Why is the BH Information Paradox Called a Paradox?
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A Relation of Electromagnetic Field & Field Tensor
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B How Can We Observe Black Holes Growing?
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I Is a Flat, Expanding Universe Compatible with GR and Newtonian Mechanics?
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B Rotation of Galaxies: Mass vs Dark Matter?
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B Gravity-like Force: Is Another Force Weaker Than Gravity?
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A Comparing Gullstrand-Painleve & Lemaitre Coordinates
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I GR: Practical Problem Sets w/ Solutions
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Is there really nothing faster than light?
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B Energy Conservation w/ Charged Battery Time Travel
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I Black Hole: Knock on the horizon
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I What is the Meaning of Lagrangian in Special Relativity?
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A Anti-self Dual Part (2,2) Riemann Curvature Tensor
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B Gravitational Lensing: Magnification of Galaxies
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I Applying Reisenbach Transf. to EM Wave in Microwave Oven
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I How to Measure Speed of Light & Is It Constant?
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I Gravitomagnetic Experiment: Possibility & Calculations
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I Time Travel in Newtonian Spacetime: Is it Possible?
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I Comparing Clock Rates in Accelerated vs Constant Velocity Frames
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B Can Accelerate at Constant g in Own FoR?
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I Ideal Fluids & General Relativity: Why Needed?
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B Galilean vs Lorentz Transformations: Correct Understanding?
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I How Does Time Dilation Affect the Twin Paradox in Special Relativity?
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I Constant Velocity Motion in Relativity: Radiation Effects?
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I Isotropy of the speed of light
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I General Relativity: Is it Local?
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I Deriving Special Relativity from Particle Indistinguishability
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I Gravitational vs. Electromagnetic Waves: What's the Difference?
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B Creating Artificial Black Hole: Force Requirements
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B Robert Wald's General Relativity: Energy-Momentum Relation
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I Proof of Special Relativity w/ Michelson–Morley Experiment
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Alcubierre Metric: York Time Cause and Effect
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I Light speed independent of source
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I Understand Poynting Density of Flow of Energy w/Weak Physics Background
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B Frequency of Gravitational Waves: Limit & Possibilities
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A Does Spacetime Absorb Energy in General Relativity?
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A MTW Gravitation: Exercise 5.1 | Beginner GR Stress-Energy Tensor Symmetry
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I Relative Motion vs. 'Relative' Acceleration: Twin 1 & 2
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I Reichenbach Synchronisation: Proving i=r
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I A paradox for two moving protons?
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A Local phase invariance of complex scalar field in curved spacetime
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B General Relativity: Action & Reaction in Gravitation
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I About global inertial frames in GR
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B Creating a Wormhole: Process & Theory
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B Gravity vs Acceleration: The Impact on Clocks in Reference Frame R
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I Why does a body at rest move if Gravity is not a force?
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I Relativity paradox: rocket landing in a cylinder
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I Deriving Lorentz Transformations: Hyperbolic Functions
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I Discussing General Relativity - Beliefs & Ideas
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B A difficulty with the equivalence of all inertial reference frames
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B Black Hole Entropy: Basis of Logarithm Explored
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A Energy-Momentum Tensor for 2-Body Problem: Approach
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B Can You Become a Black Hole from Approaching Light Speed?
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I Understanding Lorentz Factor & Proper Time Invariance
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A What is the Expression for the Waveform of an In-Spiralling Compact Binary?
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I Computing Volume in General Relativity: Use of Tensor & Friedmann Eqns
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I Understanding Gravity with GR: Beginner's Guide by Aerodyn
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I Does Lorentz invariance imply Einstein's synchronization convention?
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Insights Understanding the General Relativity view of gravity on Earth - Comments
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A Special Relativity: A^μ_ν Differences Explained
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I Can Gravity Escape a Black Hole?
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I Proper Time & 4-vectors: Clarification Needed
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I Is a Manifold with a Boundary Considered a True Manifold?
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I Curved space and gravitational waves
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I Klein Gordon Invariance in General Relativity
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I Definition of "Spatial X Direction" in Spacetime Context
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I Cauchy Stress Tensor in Applied Strength of Materials
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I Question on the space shuttle Challenger experimentation, in 1985
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I Adapting Schwarzschild Metric for Nonzero Λ
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A Vec norm in polar coordinates differs from norm in Cartesian coordinates
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B Light Speed in Vacuum: Does It Reach Cosmic Limit?
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B Constant Speed of Light: Low Speed Explained
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B Experience Travel on a Photon: Hitch-Hiker's Guide to the Universe
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B Can We "See" Effect Before Its Cause?
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B Time and Space Distortions of Photons: What Am I Misunderstanding?
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I Time Dilation along Multiple Axes
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A Understand (k,l) Tensors in Gen. Relativity
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B Time Dilation: 2 Clocks in Same Ref Frame?
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I Essential Math Topics for GR: Semi-Riemannian Geometry (Newman)
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