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 Question about a Square Light Clock
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High School Gravity and speed of information for orbiting planets
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High School A question about warp bubbles and navigation
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Graduate Question about Weinberg's GR book
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Graduate Singularity Formation and Breakdown Ricci Tensor
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Graduate The Causal Bootstrap Paradox in General Relativity
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Undergrad Theoretically, can perfectly flat spacetime exist in the Universe?
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Undergrad Reframing Light Bending Using Density Instead of Radius
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Undergrad Why Is the Speed of Light Essential in 4-Velocity Invariance?
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Undergrad Intuitive look at bending of light by gravity
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Undergrad A "continous" gravitational field formula r=0 to infinity
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Graduate Question on Dirac's derivatives of the 4-velocity w.r.t. coordinates
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Graduate Sidney Coleman's Lectures on Relativity: New Book by CUP
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Graduate Does the New Paper on Singularities Offer Proof of Their Existence?
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Graduate Tensors in null basis
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Undergrad Another Time Dilation Question
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Undergrad ##\epsilon_{ijk}## in terms of ##\delta's##
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High School Does the gravitational distortion of mass still exist in the past?
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Undergrad Missing proof of the Shell theorem in General Relativity
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Graduate A Question on the TOV Limit: Continuous Forces vs. a Discrete Trigger
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Undergrad Effect of Radiation Pressure on a Moving Object
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Graduate Does the EP imply that a free-falling observer follows a geodesic?
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Undergrad Temporal length vs. Temporal displacement
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Graduate Covariant form of Maxwell's (inhomogeneous) equations (in GR)
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Graduate Error in Landau-Lifshitz Vol 2, Fig. 20, page 310
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Graduate "TImescape" models
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High School Mass of a gyroscope when rotating or not rotating
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High School A photon always travels in a black hole
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Undergrad Going Up-Down Elevator G-forces vs Bouncing off a Spring G-force
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High School Michelson Morley experiment and the Doppler effect
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Undergrad A thought about visualizing space-time
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High School Relativity and Biological Aging: How Time Dilation Slows Cell Activity
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Graduate Minimal property of Spacelike geodesics in GR/curved spacetime?
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High School An issue about the twin paradox
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High School Can mass/energy simply be distorted spacetime?
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Undergrad Principle of relativity in the proof of invariance of interval
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Undergrad Why are we looking for a graviton?
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Undergrad Epstein diagrams and a traveling ship
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High School Lorentz Transformation of Electric & Magnetic Fields Visualized
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Graduate Ricci tensor for Fermi normal coordinates
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High School Time Travel: Is it Physically Possible? | Scientific American
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Undergrad Question about geometrical engineering (placeholder name)
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Graduate "Looks" of gravitational wave emissions for an eclipsing ternary compact object?
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Graduate Is parallel transport exactly norm-preserving or only approximately?
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High School No object actually approaches the speed of light
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Undergrad What does g00 element of the Schwarzschild metric tensor tell us?
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High School Can anything work (including human brains) inside a black hole?
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Undergrad Integral subbundle of 6 KVFs gives a spacetime foliation by 3d hypersurfaces
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Undergrad A textbook passage describing coordinate lines in physical space
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High School When I jump up and down what is the Einsteinian way to describe it?
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Undergrad Twin Paradox Resolution
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Undergrad Notion of parallel worldlines in curved geometry
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High School Question about “Inertia arises from interaction with the Universe’s mass”
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Graduate Landau-Lifshitz pseudotensor - expressing the EM tensor ##T^{ik}##
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High School Space travel and time dilation
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Undergrad Where is the mass in a black hole?
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Undergrad Can light be reflected in a black hole?
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Undergrad Reconciling smooth spacetime with variable, rotating, earth gravity
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High School Is Gravity an illusion of a force but really a curvature of spacetime?
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High School Meaningfulness of the speed of light
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Undergrad Measuring the Spacetime Interval with a Ruler
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Undergrad Does the metric in general relativity depend only on position because of the equivalence principle?
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High School One-Way Speed of Light
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High School If light beam travels through a vacuum, then through diamond, then through more vacuum...
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Undergrad About the meaning of "expanding universe"
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Undergrad CTC on FLRW cosmological models
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Graduate Vanishing of an integral of a divergence over a closed surface
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Undergrad Spacetime topology of the Universe
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Undergrad Clock rate in hyperbolic space-time manifold
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Undergrad E=mc^2 and acceleration
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Undergrad [SR] light shot at an angle in a moving train
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Graduate Velocity Verlet for relativistic simulation
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Undergrad Relativistic Doppler effect and refraction
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Undergrad "Exploring Time Perception Across Different Regions of Space"
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Undergrad Black hole and coordinate time from the perspective of Alice outside
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High School Do all events in my past lightcone have fewer past events in theirs?
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Graduate Dirac on localization of energy in the gravitational field
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Undergrad Field equation interpretation
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Undergrad Black hole formation and infinite redshift
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Undergrad Two-way light speed invariance
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High School A question about the self consistency principle
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High School Prove the velocity of a moving object is absolute in one IRF?
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Undergrad Are equations for spacetime intervals correct?
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Undergrad Is there a maximum relativistic acceleration?
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High School Drawing a Minkowski diagram to show multiple Points of View
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Undergrad Why is Rømer's light speed measurement not one-way?
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High School Does Spacetime Have Physical Existence?
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Graduate Value of quintessence while studying black hole thermodynamics
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Undergrad Relativity of Simultaneity question (use Einstein synchronization)
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Undergrad How to correctly mark event B on the picture?
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Undergrad Non-Inertial Relativistic Dynamics
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Graduate The wave vector ##k_\mu## in curved spacetime
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Undergrad Chain of lights falling into a black hole
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Graduate Spacetime model of evaporating black hole
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Undergrad An alternative derivation of the equation of motion in General Relativity
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Undergrad Alive in one frame and dead relative to other?
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Undergrad You can't actually enter a blackhole?
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Graduate Spacetime interval in Galilean relativity
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Graduate Dirac's derivation of the action/Lagrangian for a free particle
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Undergrad Relating orthogonal accelerations in special relativity
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