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 Integration of energy-momentum pseudotensor for Kerr BH
  • anuttarasammyak
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Undergrad Why is the speed of light the same everywhere in the Universe?
  • Rick16
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Graduate Jackson: justification of the Poynting vector by GR
  • coquelicot
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Undergrad Relativity of simultaneity in actuality
  • vibhuav
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High School Reciprocal time dilation
  • fuentes1979
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High School Photon Energy Without Rest Mass – How?
  • Uncle Thi
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Undergrad The wave equation interpretation of special relativity
  • gentzen
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High School Is there a white hole inside every black hole?
  • marees
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Undergrad Synchronizing clocks at different locations to measure speed of light
  • ESponge2000
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Undergrad An invariant while crossing the horizon
  • Tomas Vencl
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Undergrad I don't see how a black hole's event horizon can be crossed
  • Foretranimal
  • · Replies 73 ·
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Undergrad Variation of the lightning train thought experiment
  • FeynmanFtw
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High School Project GRE^2AT - GR on Mt. Ranier
  • DaveC426913
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Undergrad How Is Intrinsic Curvature Measured in Higher Dimensions Like 4D Spacetime?
  • geordief
  • · Replies 19 ·
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Undergrad Conventionality of the One-Way Speed of Light
  • MrRobotoToo
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High School Trying to calculate proper time of worldlines using rotating frames
  • Karin Helene Elise
  • · Replies 35 ·
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Graduate Reconciling units for the Einstein and Landau-Lifshitz pseudotensors
  • Kostik
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Undergrad What Are the Limits of the Universe According to Cosmologists?
  • .Scott
  • · Replies 47 ·
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Graduate Dirac's integral for the energy-momentum of the gravitational field
  • Kostik
  • · Replies 38 ·
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Graduate Help me understand why “Block Universe” is not scientifically proven
  • ojitojuntos
  • · Replies 45 ·
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High School Could we ever create a black hole?
  • atlanticus
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Undergrad Follow-up Einstein Definition of Simultaneity for Langevin Observers
  • cianfa72
  • · Replies 3 ·
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Undergrad Symmetry of motion in the special theory of relativity
  • qnt200
  • · Replies 37 ·
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Undergrad Hawking After 54 Years Confirmed: BH surfaces don't shrink
  • fresh_42
  • · Replies 9 ·
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Undergrad A sufficient condition for integrability of equation ##\nabla g=0##
  • Jianbing_Shao
  • · Replies 71 ·
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Undergrad Follow-up on the Expanding Universe Insight article
  • cianfa72
  • · Replies 2 ·
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Insights Relativator (Circular Slide-Rule): Simulated with Desmos - Insight
  • Greg Bernhardt
  • · Replies 1 ·
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Undergrad How do Tensors "work" in relation to linear algebraic objects?
  • Sciencemaster
  • · Replies 7 ·
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Undergrad Confused about time dilation -- motion vs energy
  • mr John wheeler
  • · Replies 9 ·
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Graduate 1-Way Speed of Light
  • James Hasty
  • · Replies 42 ·
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Graduate Gravitational Analysis of Wide Binaries
  • juggler
  • · Replies 13 ·
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Undergrad Mass conservation in black holes
  • Ranku
  • · Replies 8 ·
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High School How can a black hole absorb matter?
  • Line_112
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Undergrad Please explain how length contraction and time dilation result in a constant c
  • Amin2014
  • · Replies 4 ·
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Undergrad Can this experiment break Lorentz symmetry?
  • Asaad-Hamad
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Undergrad MTW exercise 21.26: junction conditions for a thin shell of dust
  • JimWhoKnew
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Undergrad Eddington’s margin of error
  • Jedothek
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High School Can frame dragging do this?
  • Ankit Doshi
  • · Replies 1 ·
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Undergrad Understanding the historical shift away from absolute simultaneity
  • Iskandarani
  • · Replies 25 ·
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Graduate Is there any topology behind factor 2 in Schwarzschild radius?
  • Anton Rize
  • · Replies 11 ·
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Graduate Is the constancy of c a postulate or a derivable theorem?
  • Iskandarani
  • · Replies 13 ·
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Undergrad How do non-diagonal indices of a metric allow for local flatness?
  • Sciencemaster
  • · Replies 22 ·
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Undergrad Transformation for Lemaitre coordinates
  • Dale
  • · Replies 8 ·
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High School What reference frame is used for the velocity v in the Lorentz transformation?
  • Huangdongcheng
  • · Replies 53 ·
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High School Oberth Effect Near Sag A*
  • Devin-M
  • · Replies 35 ·
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Graduate Error in Landau-Lifshitz Vol 2, equation (2), page 277
  • shin1980
  • · Replies 10 ·
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High School Debating the Validity of a Conversion Factor for Mass-Energy Equivalence
  • suoercat
  • · Replies 13 ·
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High School Can an expanding EM be quantized: E=mc^2?
  • physicsforman
  • · Replies 11 ·
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Undergrad Gravitation (MTW) Misner Thorne Wheeler - 50 years (RIP) C.W.Misner
  • robphy
  • · Replies 9 ·
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High School Conservation of kinetic energy in expanding space
  • rocknrollkieran
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Graduate A global energy conservation law in general relativity
  • Kostik
  • · Replies 36 ·
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Undergrad Gravitational lensing of gravitational waves - real?
  • Al_
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Graduate Uncertainties in the proof of Proposition 4.4.2 in Hawking and Ellis
  • gasgas
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Graduate Weinberg's proof of ##{T^{\mu\nu}}_{,\nu}=0## for a perfect fluid
  • Kostik
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Graduate How do you convert the Pound–Rebka redshift into time variation?
  • ARChohan
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High School Relativistic contraction factor
  • south
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Graduate Looking for linear frame dragging formula
  • Jonathan Scott
  • · Replies 3 ·
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Undergrad Freefall and gravity
  • Ranku
  • · Replies 10 ·
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Graduate Dirac's "comprehensive action principle" -- independent equations
  • Kostik
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High School Time dilation for two clocks at different altitudes on Earth
  • zuz
  • · Replies 14 ·
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Graduate Dirac's "GTR" Eq (27.4): how momentum ##p^\mu## varies
  • Kostik
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Undergrad How does GR deal with pointlike objects with mass?
  • JC_Silver
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Undergrad Shwartzschild coordinate system
  • omidj
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Undergrad How to calculate basis vectors from metric tensor (as a matrix)?
  • Tachytaenius
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Graduate Weyl tensor and coordinate acceleration
  • Povel
  • · Replies 12 ·
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High School Geometric and arithmetic means and contraction factor
  • south
  • · Replies 6 ·
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Undergrad Question about a Square Light Clock
  • south
  • · Replies 8 ·
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High School Gravity and speed of information for orbiting planets
  • HansH
  • · Replies 22 ·
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High School A question about warp bubbles and navigation
  • Luis
  • · Replies 22 ·
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Graduate Question about Weinberg's GR book
  • LordShadow_05
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Graduate Singularity Formation and Breakdown Ricci Tensor
  • Alien101
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Graduate The Causal Bootstrap Paradox in General Relativity
  • Alien101
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Undergrad Theoretically, can perfectly flat spacetime exist in the Universe?
  • John Constantine
  • · Replies 31 ·
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Undergrad Reframing Light Bending Using Density Instead of Radius
  • Owe Kristiansen
  • · Replies 20 ·
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Undergrad Why Is the Speed of Light Essential in 4-Velocity Invariance?
  • omidj
  • · Replies 11 ·
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Undergrad Intuitive look at bending of light by gravity
  • Owe Kristiansen
  • · Replies 25 ·
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Undergrad A "continous" gravitational field formula r=0 to infinity
  • Owe Kristiansen
  • · Replies 16 ·
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Graduate Question on Dirac's derivatives of the 4-velocity w.r.t. coordinates
  • Kostik
  • · Replies 53 ·
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Graduate Sidney Coleman's Lectures on Relativity: New Book by CUP
  • physicsworks
  • · Replies 5 ·
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Graduate Does the New Paper on Singularities Offer Proof of Their Existence?
  • windy miller
  • · Replies 6 ·
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Graduate Tensors in null basis
  • Antarres
  • · Replies 9 ·
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Undergrad ##\epsilon_{ijk}## in terms of ##\delta's##
  • brotherbobby
  • · Replies 3 ·
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High School Does the gravitational distortion of mass still exist in the past?
  • Giblet
  • · Replies 28 ·
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Undergrad Missing proof of the Shell theorem in General Relativity
  • Bosko
  • · Replies 34 ·
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Graduate A Question on the TOV Limit: Continuous Forces vs. a Discrete Trigger
  • euquila
  • · Replies 10 ·
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Undergrad Effect of Radiation Pressure on a Moving Object
  • wnvl2
  • · Replies 31 ·
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Graduate Does the EP imply that a free-falling observer follows a geodesic?
  • Kostik
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Undergrad Temporal length vs. Temporal displacement
  • LeeE
  • · Replies 10 ·
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Graduate Covariant form of Maxwell's (inhomogeneous) equations (in GR)
  • Kostik
  • · Replies 9 ·
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Graduate "TImescape" models
  • pervect
  • · Replies 5 ·
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High School Mass of a gyroscope when rotating or not rotating
  • HansH
  • · Replies 13 ·
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High School A photon always travels in a black hole
  • Koning_D
  • · Replies 9 ·
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Undergrad Going Up-Down Elevator G-forces vs Bouncing off a Spring G-force
  • ESponge2000
  • · Replies 5 ·
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High School Michelson Morley experiment and the Doppler effect
  • Luyo_66
  • · Replies 21 ·
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Undergrad A thought about visualizing space-time
  • InquiringMind
  • · Replies 24 ·
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High School Relativity and Biological Aging: How Time Dilation Slows Cell Activity
  • faz19_
  • · Replies 14 ·
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Graduate Minimal property of Spacelike geodesics in GR/curved spacetime?
  • Kostik
  • · Replies 76 ·
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High School An issue about the twin paradox
  • dwspacetime
  • · Replies 24 ·
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High School Can mass/energy simply be distorted spacetime?
  • physicsisdope
  • · Replies 9 ·
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Undergrad Principle of relativity in the proof of invariance of interval
  • Mike_bb
  • · Replies 53 ·
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