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.
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FAQ: Experimental Basis of Special Relativity
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Insights When Discussing the Twin Paradox: Read This First
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Insights Maxwell’s Equations in a Static, Spherically Symmetric Spacetime
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Insights An Introduction to the Generation of Mass from Energy
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Relativity Insights: FAQs on Photons, Gravity, Time Dilation, and More!
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I Can a Gyroscope in a Satellite Detect Orbit?
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I Physical Interpretation of Frame Field
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I Is this another "paradox" or a veritasium mistake?
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A Assumptions of Hawking-Penrose 1970 Singularity Theorem
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I Gyroscope angular momentum: direction and curvature
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I Euclidean geometry and gravity
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I About the notion of non-standard inertial frame
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I Is using r as a coordinate in Birkhoff's theorem a limitation?
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I Question about special relativity and magnetism
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I The Einstein Clock aka Light Clock
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B Train Fall Paradox
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I Integration of energy-momentum pseudotensor for Kerr BH
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I Question about Parallel Transport
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A Jackson: justification of the Poynting vector by GR
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I Relativity of simultaneity in actuality
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I EPR revisited
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B Why Do Events Freeze For Me at the Speed of Light?
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B Reciprocal time dilation
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B Photon Energy Without Rest Mass – How?
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I The wave equation interpretation of special relativity
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A Is the variation of the metric ##\delta g_{\mu\nu}## a tensor?
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I Synchronizing clocks at different locations to measure speed of light
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I Convention for writing $\binom{1}{1}$ tensors in matrix form?
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I Synchronizing clocks in an inertial frame if light is anisotropic
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I An invariant while crossing the horizon
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I I don't see how a black hole's event horizon can be crossed
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I Variation of the lightning train thought experiment
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B Project GRE^2AT - GR on Mt. Ranier
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I How Is Intrinsic Curvature Measured in Higher Dimensions Like 4D Spacetime?
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I Conventionality of the One-Way Speed of Light
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B Trying to calculate proper time of worldlines using rotating frames
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A Reconciling units for the Einstein and Landau-Lifshitz pseudotensors
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I What Are the Limits of the Universe According to Cosmologists?
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A Dirac's integral for the energy-momentum of the gravitational field
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Help me understand why “Block Universe” is not scientifically proven
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B Could we ever create a black hole?
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I Follow-up Einstein Definition of Simultaneity for Langevin Observers
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I Symmetry of motion in the special theory of relativity
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I Hawking After 54 Years Confirmed: BH surfaces don't shrink
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I A sufficient condition for integrability of equation ##\nabla g=0##
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I Follow-up on the Expanding Universe Insight article
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Insights Relativator (Circular Slide-Rule): Simulated with Desmos - Insight
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I How do Tensors "work" in relation to linear algebraic objects?
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I Confused about time dilation -- motion vs energy
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A 1-Way Speed of Light
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A Gravitational Analysis of Wide Binaries
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I Mass conservation in black holes
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B How can a black hole absorb matter?
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I Please explain how length contraction and time dilation result in a constant c
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I Can this experiment break Lorentz symmetry?
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I MTW exercise 21.26: junction conditions for a thin shell of dust
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I Eddington’s margin of error
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B Can frame dragging do this?
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I Understanding the historical shift away from absolute simultaneity
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A Is there any topology behind factor 2 in Schwarzschild radius?
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A Is the constancy of c a postulate or a derivable theorem?
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I How do non-diagonal indices of a metric allow for local flatness?
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I Transformation for Lemaitre coordinates
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B What reference frame is used for the velocity v in the Lorentz transformation?
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B Oberth Effect Near Sag A*
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A Error in Landau-Lifshitz Vol 2, equation (2), page 277
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B Debating the Validity of a Conversion Factor for Mass-Energy Equivalence
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B Can an expanding EM be quantized: E=mc^2?
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I Gravitation (MTW) Misner Thorne Wheeler - 50 years (RIP) C.W.Misner
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A A global energy conservation law in general relativity
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I Gravitational lensing of gravitational waves - real?
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A Uncertainties in the proof of Proposition 4.4.2 in Hawking and Ellis
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A Weinberg's proof of ##{T^{\mu\nu}}_{,\nu}=0## for a perfect fluid
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A How do you convert the Pound–Rebka redshift into time variation?
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B Relativistic contraction factor
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A Looking for linear frame dragging formula
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I Freefall and gravity
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A Dirac's "comprehensive action principle" -- independent equations
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B Time dilation for two clocks at different altitudes on Earth
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A Dirac's "GTR" Eq (27.4): how momentum ##p^\mu## varies
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I How does GR deal with pointlike objects with mass?
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I Shwartzschild coordinate system
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I How to calculate basis vectors from metric tensor (as a matrix)?
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B Can Curved Spacetime Enable Faster-Than-Light Travel?
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A Weyl tensor and coordinate acceleration
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I With gravitational lensing, which way is down?
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A The Lagrangian of a free particle ##L=-m \, ds/dt##
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B Geometric and arithmetic means and contraction factor
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I Question about a Square Light Clock
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B Gravity and speed of information for orbiting planets
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B A question about warp bubbles and navigation
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A Question about Weinberg's GR book
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A Singularity Formation and Breakdown Ricci Tensor
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A The Causal Bootstrap Paradox in General Relativity
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I Theoretically, can perfectly flat spacetime exist in the Universe?
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I Why Is the Speed of Light Essential in 4-Velocity Invariance?
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A Question on Dirac's derivatives of the 4-velocity w.r.t. coordinates
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A Sidney Coleman's Lectures on Relativity: New Book by CUP
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A Does the New Paper on Singularities Offer Proof of Their Existence?
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A Tensors in null basis
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I Another Time Dilation Question
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I ##\epsilon_{ijk}## in terms of ##\delta's##
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B Does the gravitational distortion of mass still exist in the past?
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I Missing proof of the Shell theorem in General Relativity
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A A Question on the TOV Limit: Continuous Forces vs. a Discrete Trigger
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