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 Car, wheels and Lorentz contraction of the road: Is this a Paradox?
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Undergrad Invariant Mass-Energy in FRW Spacetime
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Undergrad Galilean relativity in terms of homogeneity
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Undergrad What was the four-momentum meant to include?
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Undergrad Noether's second theorem: two questions
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Undergrad Condition for Centering Starlight in a Water-Filled Telescope?
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Undergrad Did Born Rigidity Lead Einstein to Conclude Spacetime is Curved?
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Undergrad Quasi-local mass as a measure of the gravitational energy?
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High School Trying to understand what "time" is (layperson)
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Undergrad Lorentz Transformation: Premises + Derivation
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Undergrad Coulomb’s Law in a Moving Reference Frame
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Undergrad Measuring Time Dilation from 25Kg Lead Brick w/3 Cesium Oscillators
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Undergrad Covariant Derivative Rank 2 Contravariant Tensor
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High School What is the Experimental Basis of Special Relativity?
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Undergrad Observer on Earth watching a spaceship traveling at c/2
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High School How to compare the proper times of two spatially distant mass points?
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High School What is the effect of the twin paradoxon?
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High School A scenario to help understand the twin paradox in SR
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High School Why does length contraction occur and how does it relate to time dilation?
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Undergrad Three inertial particles: Separating the twins from the paradox
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Undergrad Yet another spacetime-bending layman question
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Graduate What's the relationship between RMS framework and the Lorentz group?
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Graduate Papapetrou transformation: Conditions to be satisfied to achieve transformation
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High School Max Speed of Molecules: 1 Electron Stripped?
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Undergrad Does the past of an observer still actually exist in their "now"?
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High School Time dilation in a planet-moon system
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High School Are planetary orbits elliptical because of a space–time conic section?
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Undergrad Forces and gravitational time dilation
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Undergrad How to derive irreducible representations/tensors?
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High School Measuring Speed of Light: Transit Time & Interference
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High School Length Contraction: Apple Hanging from Tree & Earth
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Undergrad How does an observer moving at relativistic speeds perceive a pulsar?
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High School If gravity was a force wouldn't going back in time cause us to float?
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High School Transfer speeds of forces affected by time dilation?
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Undergrad Is There an Atomic Clock Experiment on the Moon Testing Relativity?
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High School The expansion of the Universe and time travel (By a non-scientist)
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High School What does 3-dimensional space deform into, in the presence of gravity?
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Undergrad Relevant/irrelevant clocks for experimental tests of relativity
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High School Photons on a perpendicular bisector path from a black hole's core
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Undergrad Atomic Clock Speed graph between two stationary masses
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Undergrad Event Horizon movie, with some interesting concepts (papers cited)
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Undergrad Any advancements in the feasibility of Alcubierre warp drive science?
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High School Detecting cosmological redshift in an empty part of the Universe
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Undergrad Stress-energy tensor and energy/momentum conservation clarification
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High School Define a vector that transfers the reference systems to the future
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Undergrad Why is there nothing faster than light?
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Undergrad Constancy of Speed of Light: Postulate or Assumption?
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Undergrad Radiatively efficient accretion onto BHs
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Undergrad Time Measurement in Extremely Curved Space Regions
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Graduate Preserving Covariant Derivatives of Null Vectors Under Variation
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High School Does the fact that gravity moves at the speed of light affect how planets move?
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Graduate Continuation of Coordinates Across Black Hole Horizons
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Undergrad Mass Density of Photons in Refractive Medium
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Undergrad Taylor Expansion of Metric Transformation in RNCs
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High School Sun's Mass Loss: 4 Billion kg/sec from Sunlight & Ejected Particles
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Undergrad Compatibility of Classical Electromagnetism & Relativity
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High School Can Relativistic Mass Create a Black Hole?
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High School Pound & Rebka Experiment: Earth's Spin Rotation Speed
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Undergrad 3 clocks thought experiment - Absolute vs. relative aspects?
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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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Undergrad 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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Undergrad Gravitational field modulation of a moving mass
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High School Do Gravitational Forces Increase for Objects Moving at Light Speed?
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High School Gravity waves and Planck's constant
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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 How do fields retain their uniformity with interposing objects?
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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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