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 Did the Michelson-Morley Experiment Disprove the Ether Theory?
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Undergrad Gravitational wave propagation in GR
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Undergrad Information transfer between moving bodies - sped up or slowed down?
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Graduate Dirac "GTR" Eq. 27.11 -- how to show that a boundary term vanishes?
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Undergrad Does expanding space cause cosmological redshift?
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Undergrad What if one is in 1905 and debating foundational fundamentals?
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Undergrad Couple questions about time re-scaling function in Birkhoff’s theorem
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High School Formation of a black hole using acceleration
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Undergrad Proving speed of light constant “c” is the same in all directions?
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Graduate Proof of covariant derivative of spinor
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Undergrad Intra-Universe Wormhole Metrics
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Undergrad General Relativity and the precession of the perihelion of Mercury
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Undergrad Does gravity bend gravitational waves?
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Undergrad When time is not orthogonal to phi, that means there is a preferred direction in space? How?
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Undergrad Basic Special Relativity question but the math isn’t working
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Undergrad Are gravitons necessary?
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Graduate Proving that Levi-Civita tensor density is invariant
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Undergrad Can you indeed rescue a person from a Black Hole?
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Graduate Relativity: Test charge moving perpendicular to a current carrying wire exhibits a force
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High School How to intuitively understand the formula S² = x² - c²t²
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Undergrad Why isn't TT gauge over constrained?
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Undergrad Minkowski to Euclidean line element from coordinate changes?
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Graduate Diffeo-invariant action for a matter covector field
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Undergrad Final part of proof of timelike Killing w/ Frobenius --> static
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Undergrad Einstein field equations
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Undergrad Online Christoffel Symbols Calculator
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High School Question about bendability of objects in 4 dimensions
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Undergrad A question about Relativity of Time using Time dilation experiment
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Undergrad On the existence of Gravitational energy in General relativity
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Undergrad Null energy condition constrains the metric
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Undergrad SR flat Lorentzian manifold and Anderson simultaneity convention
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Undergrad The generators of a ``Poincare-type'' group in momentum space
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Undergrad Understanding Spacetime simultaneity in twin paradox scenarios
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Undergrad Construct a Diagram that Illustrates The Galilean Law of Addition of Velocities
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Undergrad Standing light waves if the one-way speed of light were not constant?
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Undergrad Evaporating black hole: First principles consideration
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High School Falling into a black hole
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Undergrad Pullback & orthogonal projector
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Undergrad Unruh Radiation and Black Holes
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High School Is velocity the reason for the time dilation effect?
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Undergrad What Would the Universe Look Like as a Manifold with Boundary?
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Undergrad How to get metric field using a path dependent parallel propagator
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Undergrad What are Killing vectors?
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Undergrad Is this a Killing vector field?
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Undergrad Which theory of time is the most evidence-based?
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High School Implications of negative Michelson-Morley result
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Graduate Variation of CMFR mass density ##\rho## along a world line
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Undergrad Time dilation from galactic gravitational mass
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High School Detection of red-shifted photons near an event horizon
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Undergrad Is time dilation a real effect?
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Undergrad Falling through the event horizon of an evaporating black hole
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High School Mass defect and electron transition
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Graduate Synchronous to Newtonian gauge
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Undergrad A. P. French "Matter and Radiation: The Inertia of Energy"
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High School Excellent Free Course On Einsten, Relativity, His Views Etc from Harvard
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Undergrad Killing fields commute if they are asymptotically coordinate?
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Undergrad Meaning of the invariants built from the angular momentum tensor
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Undergrad Conservation of stress-energy tensor
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Undergrad Can the expansion of the Universe reduce the energy of a photon to 0?
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Graduate Boundary conditions in ##\delta I=0## to derive Einstein's equations
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Undergrad Orbital Period In General Relativity
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Undergrad Strange index notation for linear transformation matrix
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Undergrad Israel Junction Conditions: Finding Continuous Metric Across Shell
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Undergrad Dark energy and conservation of energy
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Undergrad On the physical meaning of Minkowski's spacetime model
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Undergrad Why Does a Charged Box Exhibit Higher Inertia Due to Mass-Energy Equivalence?
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High School Why is it impossible to go faster than the speed of light?
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Undergrad Linearised gravity approach to Lense Thirring metric
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Undergrad Black Holes Colliding Exactly Head On
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Graduate What does Dirac mean by "the suffixes would not balance"?
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Graduate How do we interpret measurements of Mercury's position?
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Graduate Dirac comment on tensor densities (Dirac GTR, p. 37)
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Undergrad Transition of spherically symmetric gravitation
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Graduate Dirac's coordinates ##(\tau, \rho)## for the Schwarzschild metric with ##r \le 2m##
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Graduate Variation of the kinetic term in scalar field theory
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High School Do observers always agree on the number of waves in a beam of light?
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Undergrad Questions about Hawking radiation and extremal black holes...?
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Undergrad Coordinate Transformation versus Change of Synchrony Convention
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High School Help understanding the Relativity of Simultaneity
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High School Entering a black hole -- I know I must be wrong (Help me understand why)
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Undergrad Einstein brother-in-law elevator
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Undergrad Bell's spaceship paradox
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Undergrad Ricci tensor from this action
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Undergrad How Relativistic Speeds Affect Time Perception on a Spaceship
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High School How are 'fringe shifts' in the Michelson-Morley experiment calculated?
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Undergrad Explanation for Galaxy Rotation Curves
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Undergrad One difference between GR and quantum mechanics
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Undergrad Move Stress-Energy tensor to the left side of EFE?
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Undergrad Would moving the mouths of a wormhole affect the internal distance?
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Undergrad Photon in a mirrored box moving in direction of travel
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High School Energy loss of a photon
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Undergrad Battery life on VERY fast moving object
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High School Time and right angle traveling twins paradox
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Undergrad A problem in the equations for Einstein's Special Theory of Relativity
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Undergrad What is the fabric of space-time made up of?
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Undergrad Does the speed of light pop out of other theories than EM?
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Undergrad Why are rotated parallel axes still parallel?
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High School Prove that metric tensor is covariant constant
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Undergrad How relative is the magnetic field of a current carrying conductor?
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Undergrad The answer for the total mass of the Universe?
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