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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Graduate 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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Graduate Relativity Insights: FAQs on Photons, Gravity, Time Dilation, and More!
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High School Why does a Wormhole not look like an hourglass?
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High School Need tips to understand Relativistic Energy in Special Relativity
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5
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412
High School Traveling through space at zero km/s
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11
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540
Graduate Kruskal Coordinates in Schwartzchild metric
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9
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465
Undergrad Convention for writing $\binom{1}{1}$ tensors in matrix form?
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Undergrad EPR revisited
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Undergrad Derive the Lorentz transformation in Minkowski four-dimensional spacetime spacetime
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Undergrad Relational event horizons?
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553
Graduate Stumped by a Lagrangian in Einstein's 1916 paper
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414
High School Am I understanding the concept of proper frame of reference?
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High School Why is the constant speed of light so unique?
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Undergrad Synchronizing clocks in an inertial frame if light is anisotropic
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High School Why Do Events Freeze For Me at the Speed of Light?
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4
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736
Undergrad Revisiting the Light Clock
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Undergrad Question about Parallel Transport
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High School Thought Experiment: Behavior of shadow of object moving at speed c
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Undergrad Can a Gyroscope in a Satellite Detect Orbit?
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Undergrad Physical Interpretation of Frame Field
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Undergrad Is this another "paradox" or a veritasium mistake?
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Graduate Assumptions of Hawking-Penrose 1970 Singularity Theorem
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35
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Undergrad Gyroscope angular momentum: direction and curvature
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Undergrad Euclidean geometry and gravity
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162
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Undergrad Does a person's mass affect time?
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6
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Undergrad About the notion of non-standard inertial frame
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Undergrad Is using r as a coordinate in Birkhoff's theorem a limitation?
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22
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Undergrad Question about special relativity and magnetism
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5
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Undergrad The Einstein Clock aka Light Clock
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High School Train Fall Paradox
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Undergrad Integration of energy-momentum pseudotensor for Kerr BH
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4
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Undergrad Why is the speed of light the same everywhere in the Universe?
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Graduate Jackson: justification of the Poynting vector by GR
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Undergrad Relativity of simultaneity in actuality
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12
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High School Reciprocal time dilation
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15
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High School Photon Energy Without Rest Mass – How?
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Undergrad The wave equation interpretation of special relativity
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Graduate Is the variation of the metric ##\delta g_{\mu\nu}## a tensor?
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High School Is there a white hole inside every black hole?
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Undergrad Synchronizing clocks at different locations to measure speed of light
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Undergrad An invariant while crossing the horizon
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Undergrad I don't see how a black hole's event horizon can be crossed
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Undergrad Variation of the lightning train thought experiment
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High School Project GRE^2AT - GR on Mt. Ranier
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Undergrad How Is Intrinsic Curvature Measured in Higher Dimensions Like 4D Spacetime?
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Undergrad Conventionality of the One-Way Speed of Light
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High School Trying to calculate proper time of worldlines using rotating frames
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Graduate Reconciling units for the Einstein and Landau-Lifshitz pseudotensors
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Undergrad What Are the Limits of the Universe According to Cosmologists?
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Graduate Dirac's integral for the energy-momentum of the gravitational field
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Graduate Help me understand why “Block Universe” is not scientifically proven
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High School Could we ever create a black hole?
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Undergrad Follow-up Einstein Definition of Simultaneity for Langevin Observers
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Undergrad Symmetry of motion in the special theory of relativity
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Undergrad Hawking After 54 Years Confirmed: BH surfaces don't shrink
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Undergrad A sufficient condition for integrability of equation ##\nabla g=0##
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Undergrad 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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Undergrad How do Tensors "work" in relation to linear algebraic objects?
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Undergrad Confused about time dilation -- motion vs energy
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Graduate 1-Way Speed of Light
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Graduate Gravitational Analysis of Wide Binaries
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Undergrad Mass conservation in black holes
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High School How can a black hole absorb matter?
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Undergrad Please explain how length contraction and time dilation result in a constant c
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Undergrad Can this experiment break Lorentz symmetry?
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Undergrad MTW exercise 21.26: junction conditions for a thin shell of dust
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Undergrad Eddington’s margin of error
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High School Can frame dragging do this?
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580
Undergrad Understanding the historical shift away from absolute simultaneity
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Graduate Is there any topology behind factor 2 in Schwarzschild radius?
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Graduate Is the constancy of c a postulate or a derivable theorem?
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Undergrad How do non-diagonal indices of a metric allow for local flatness?
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Undergrad Transformation for Lemaitre coordinates
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High School What reference frame is used for the velocity v in the Lorentz transformation?
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High School Oberth Effect Near Sag A*
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Graduate Error in Landau-Lifshitz Vol 2, equation (2), page 277
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High School Debating the Validity of a Conversion Factor for Mass-Energy Equivalence
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High School Can an expanding EM be quantized: E=mc^2?
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Undergrad Gravitation (MTW) Misner Thorne Wheeler - 50 years (RIP) C.W.Misner
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High School Conservation of kinetic energy in expanding space
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Graduate A global energy conservation law in general relativity
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Undergrad Gravitational lensing of gravitational waves - real?
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Graduate Uncertainties in the proof of Proposition 4.4.2 in Hawking and Ellis
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Graduate Weinberg's proof of ##{T^{\mu\nu}}_{,\nu}=0## for a perfect fluid
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Graduate How do you convert the Pound–Rebka redshift into time variation?
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High School Relativistic contraction factor
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Graduate Looking for linear frame dragging formula
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Undergrad Freefall and gravity
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Graduate Dirac's "comprehensive action principle" -- independent equations
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High School Time dilation for two clocks at different altitudes on Earth
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Graduate Dirac's "GTR" Eq (27.4): how momentum ##p^\mu## varies
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Undergrad How does GR deal with pointlike objects with mass?
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Undergrad Shwartzschild coordinate system
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Undergrad How to calculate basis vectors from metric tensor (as a matrix)?
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6
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High School Can Curved Spacetime Enable Faster-Than-Light Travel?
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Graduate Weyl tensor and coordinate acceleration
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Undergrad With gravitational lensing, which way is down?
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Graduate The Lagrangian of a free particle ##L=-m \, ds/dt##
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High School Geometric and arithmetic means and contraction factor
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Undergrad Question about a Square Light Clock
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8
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High School Gravity and speed of information for orbiting planets
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