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 Why are we looking for a graviton?
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Undergrad Epstein diagrams and a traveling ship
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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 CTC on FLRW cosmological models
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Undergrad About the meaning of "expanding universe"
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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 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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High School Simplest symmetrical time dilation question
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High School Einstein thought experiment confusion: “light clock in a moving frame”
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Undergrad Angles between 4-vectors in special relativity?
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Undergrad Confusion about Cauchy surfaces
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High School Is SpaceTime just DistanceTime?
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Undergrad Lecture on Newtonian spacetime
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High School The ONE Ring has been Found
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High School Theories about light and time near a black hole
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High School Lowering a rope through the event horizon
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Undergrad Path independence redshift photon
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Undergrad Charged particles and electromagnetic waves in transparent media
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Undergrad Lasting effects of Mass and Distance Dilation
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Undergrad The Faraday disk in the context of the theory of relativity
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Undergrad 2 objects of enormous volume each in relative motion very close to c
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Undergrad When Does a Train Passenger Experience Complete Darkness in a Tunnel?
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Undergrad Matrix form of metric component transformation?
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Undergrad Energy and reference frames
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Undergrad GR as Gauge Theory
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High School Can we say that everything on the planet is made up of energy or matter?
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Graduate A better way of talking about time?
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Undergrad Are Space and Time Just an Illusion in General Relativity?
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Graduate Curvature with different connections on the two-sphere
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Undergrad Determinism & General Relativity: A Physics Primer
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Undergrad Transformation Riemann tensor to an accelerating frame
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Undergrad SR: GA Multivector vs. Tensor notation, Maxwell's equations
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Undergrad Time dilation for two observers in relative motion
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Undergrad Electromagnetic field in different reference frames
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Graduate Speed of Light for Bonnor Beam
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Undergrad Time dilation and the human body
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Undergrad If electrons can be pointlike particles, why can't black holes?
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High School Is time travel... travelling from one 3 dimensional space time to another 3 dimensional space time?
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Graduate Is Fatio–Le Sage's theory of gravitation an entropic gravity?
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High School Is time an illusion?
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High School Can we measure absolute motion of Earth and Sun?
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Undergrad Definition of tangent vector to a timelike geodesic
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Undergrad Tensor field from a covariant derivative operator (affine connection)
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Undergrad Can anyone clarify the relativistic twin paradox for me?
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Graduate Calculating geodesic equation from Hamiltonian in presence of EM
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