Special and General Relativity Forum

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.

Threads

Graduate Poisson, Einstein, Weak Energy Condition

  • astrolollo
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Graduate Exterior Schwarzschild Spacetime Defined

  • Sasha_Tw
  • · Replies 3 ·
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Graduate When do total differentials cancel with partial derivatives

  • sunrah
  • · Replies 4 ·
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Undergrad Black holes and the relativity of simultaneity

  • rjbeery
  • · Replies 3 ·
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Undergrad Is the speed of all waves constant?

  • mrsmitten
  • · Replies 12 ·
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Graduate Comparing GR multibody solutions to experiments across different gauges

  • Igorr
  • · Replies 13 ·
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Graduate What's the meaning of the norm of Poynting 4-vector?

  • andresB
  • · Replies 16 ·
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Undergrad Why don't we run out of gravitational force?

  • fredreload
  • · Replies 5 ·
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Graduate Can Gyroscopes Curvature of Space Explain Precession Motion?

  • Dukon
  • · Replies 18 ·
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Graduate More twin paradox and acceleration

  • DiracPool
  • · Replies 4 ·
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Graduate Einstein Field Equations, how many?

  • Igorr
  • · Replies 22 ·
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Graduate Breakdown of Correspondence Principle: Null Dust Case

  • victorvmotti
  • · Replies 5 ·
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Graduate Interplay of space and time in Spacetime invariant interval

  • Ittiandro
  • · Replies 44 ·
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Graduate Which definition of relativistic phase velocity is correct?

  • Helios
  • · Replies 12 ·
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Graduate Why does B conclude event Q happened before P in this relativity diagram?

  • xDk
  • · Replies 10 ·
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Graduate Is near-light speed travel relative to the observer's frame?

  • udtsith
  • · Replies 7 ·
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Undergrad How the standard spacetime model relates to reality

  • name123
  • · Replies 33 ·
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Graduate Who Hits Wall First: Light Beam or Light Traveller?

  • aboro
  • · Replies 5 ·
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Graduate Wave reflection from a moving mirror in Minkowski spacetime

  • cedricyu803
  • · Replies 2 ·
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Graduate Length contraction experiment results

  • name123
  • · Replies 7 ·
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Graduate Solve the Special Theory of Relativity Confusion

  • Shehreyar Khan
  • · Replies 4 ·
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High School What Determines the Speed of Light Limit?

  • thetexan
  • · Replies 30 ·
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Graduate Ratio of time dilation relation in different potentials

  • sunrah
  • · Replies 3 ·
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3

Graduate Question on Phenomena beyond General Relativity

  • Harry Wang
  • · Replies 2 ·
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Undergrad Why does time link gravity and masslessness?

  • toastercombo
  • · Replies 27 ·
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Graduate Light Beam Opposite Motion: Einstein Special Theory

  • MZaeemQ
  • · Replies 3 ·
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Graduate Time as a dimension, can spatial length be applied to it?

  • mcjosep
  • · Replies 11 ·
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Graduate Gravitational Time Dilation & Orbits of Objects

  • Warfen
  • · Replies 4 ·
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Graduate On the usual confusion among what it is and what is measure

  • MachPrincipe
  • · Replies 9 ·
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Graduate Toroidal solutions to Einstein's field equations

  • Zeno Marx
  • · Replies 1 ·
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Graduate Twin paradox: seeing the traveling twin arrive before light signals catch up

  • Nantes
  • · Replies 66 ·
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Graduate Producing a metric with only a single coordinate function

  • grav-universe
  • · Replies 25 ·
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Undergrad Relativity of simultaneity, understood, now not so sure.

  • DAC
  • · Replies 12 ·
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Graduate What Are the Key Effects of Special Relativity on Time and Mass?

  • fog37
  • · Replies 3 ·
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Graduate Electromagnetic Tensor in (-+++) Convention

  • tomdodd4598
  • · Replies 3 ·
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Graduate Lorentz Transformation Equation Paradox

  • Rahul Mohan P
  • · Replies 8 ·
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High School Lorentz Transformation Equation Paradox - Find Where I Went Wrong

  • Rahul Mohan P
  • · Replies 2 ·
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High School Why FTL motion doesn't create a grandfather paradox

  • MysticWizard
  • · Replies 1 ·
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Graduate If spacetime can be warped, what is its shape?

  • Fuinne
  • · Replies 4 ·
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Graduate Do Moving Objects Return to Original Length After Stopping?

  • Ut-Napishtim
  • · Replies 29 ·
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Graduate General vectors and tangent space

  • sunrah
  • · Replies 6 ·
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Graduate Question on Einstein original paper

  • DrSirius
  • · Replies 6 ·
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Graduate Is Gravity a Physical Entity Like Light Waves?

  • Fuinne
  • · Replies 3 ·
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Graduate Assuming Lorentz transform is affine

  • Erland
  • · Replies 26 ·
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Graduate Analog of Gauss' law in gravity

  • LagrangeEuler
  • · Replies 2 ·
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Graduate Can the Dot Product of Four Vectors Maintain Positive Component Signs?

  • tomdodd4598
  • · Replies 9 ·
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Graduate Does the Minkowski diagram apply to intergalactic space and cosmic expansion?

  • DiracPool
  • · Replies 14 ·
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Graduate Is the train in the circular track paradox similar to the barn/pole paradox?

  • JVNY
  • · Replies 66 ·
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Graduate Has Speed of Light Always Stayed Same?

  • JHA
  • · Replies 3 ·
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Graduate Define Mass: Travels Through Time?

  • toastercombo
  • · Replies 2 ·
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Graduate Is There a Hidden Meaning in Integrating the Lorentz Factor with Trig Sub?

  • Astro Boy 327
  • · Replies 2 ·
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Graduate Can a "density" of points create curvature?

  • friend
  • · Replies 4 ·
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Undergrad Lorentz Transformations or Dilation/Contraction?

  • NiallBucks
  • · Replies 23 ·
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Graduate Are length and time Trade-offs in relativity?

  • Dopplershift
  • · Replies 10 ·
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Graduate Null geodesic definition (by extremisation?)

  • cesiumfrog
  • · Replies 18 ·
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Graduate Independent Killing vector field

  • astrolollo
  • · Replies 3 ·
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Graduate Why does light have constant speed for all observers?

  • nandodean
  • · Replies 14 ·
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Graduate Why the midpoint of a moving train remains the midpoint

  • AlonsoMcLaren
  • · Replies 10 ·
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Graduate Does the photon have a 4-velocity in a medium?

  • PFfan01
  • · Replies 82 ·
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Graduate Unbounded perturbed geometry due to analyticity

  • CharlesJQuarra
  • · Replies 2 ·
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Graduate Does general relativity have a statistical mechanics like classical mechanics?

  • andresB
  • · Replies 15 ·
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Undergrad Hyper-Light Speed: What Happens?

  • 5P@N
  • · Replies 4 ·
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Graduate Is There More to Special Relativity?

  • arydberg
  • · Replies 6 ·
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Graduate Principle of relativity and invariance of c

  • Jose Leal
  • · Replies 1 ·
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High School Why is gravitational force always attractive in nature?

  • preitiey
  • · Replies 17 ·
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Graduate Has the speed of light been constant since the big bang?

  • Bharath Siva
  • · Replies 2 ·
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Graduate Why is pure radiation stress-energy a product of null vectors?

  • victorvmotti
  • · Replies 3 ·
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Graduate Is Time Dilation Misunderstood in Popular Science Videos?

  • seb7
  • · Replies 77 ·
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Graduate Rest frame concept for perfect fluid energy-momentum tensor

  • victorvmotti
  • · Replies 6 ·
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Graduate Why a vector field can not be used to describe gravity?

  • Chhhiral
  • · Replies 9 ·
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Graduate Why don't we account for length contraction of receding galaxies?

  • vinven7
  • · Replies 8 ·
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Graduate Does length contraction explain quantum entanglement correlations?

  • peety
  • · Replies 2 ·
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Graduate Could FTL Communication be Achieved via Mechanical Connection?

  • Glenstr
  • · Replies 5 ·
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5

Undergrad Gravitational Field Strength of 1

  • Einstein's Cat
  • · Replies 4 ·
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4

Undergrad Can someone falling into a black hole see the entire future of the universe?

  • Daniel K
  • · Replies 6 ·
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6

Graduate Reference book for ADM formalism

  • Gregg Narbett
  • · Replies 4 ·
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Graduate Looking for sources for deprecation of relativistic mass

  • MachPrincipe
  • · Replies 8 ·
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Graduate Explanation of time dilation due to c being the maximum speed

  • MachPrincipe
  • · Replies 29 ·
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29

Graduate Speed of light relative to observers?

  • dayalanand roy
  • · Replies 34 ·
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Graduate Time Dilation at ISCO for Kerr Black Holes

  • Neutrinos02
  • · Replies 2 ·
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Graduate Why does relativity say time doesn't exist but quantum mechanics treats it as flowing?

  • black hole 123
  • · Replies 3 ·
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3

Graduate Ergoregions and Energy Extraction

  • adsquestion
  • · Replies 36 ·
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Undergrad What's the fate of neutrons in black hole formation?

  • Aliasa
  • · Replies 23 ·
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High School Randall Munroe Explains General Relativity

  • Ygggdrasil
  • · Replies 20 ·
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Undergrad Relativistic Doppler Effect: Explaining the Equation

  • I'mnotarobot
  • · Replies 7 ·
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Undergrad Is X's Clock Really Slower Than Y's in the STR Argument?

  • Andy Lee
  • · Replies 11 ·
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11

Undergrad Andrei Lebed: Hydrogen Spectral Transitions Without Gravity

  • greswd
  • · Replies 2 ·
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Graduate What is the difference between Boost and Translation?

  • suvendu
  • · Replies 10 ·
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10

Graduate Circular train scenario with differential aging at equal speeds

  • JVNY
  • · Replies 29 ·
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29

High School Relationship between Mass and Speed of Light

  • Sunanda Goh
  • · Replies 4 ·
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4

Graduate Eigenvalues of curvature tensors as curvature scalars?

  • bcrowell
  • · Replies 13 ·
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Undergrad Diffraction Redshift and Emission Theory

  • greswd
  • · Replies 3 ·
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3

Graduate Can time slow down and speed up simultaneously for the same observer?

  • Ameer Bux
  • · Replies 7 ·
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Graduate Can Gravitational Binding Energy Cause Negative Effective Mass?

  • Neutrinos02
  • · Replies 6 ·
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6

Graduate Hawking radiation no change to black hole mass?

  • waywardtom
  • · Replies 16 ·
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16

High School Can a rigid rod transmit force faster than light?

  • Stig Ramone
  • · Replies 1 ·
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1

Graduate Purcell's relativity argument for magnetic force and charge distribution

  • Diaz Lilahk
  • · Replies 3 ·
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3

Graduate Is Hawking's statement of Raychaudhuri's equation wrong?

  • jinawee
  • · Replies 6 ·
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6

Graduate What is Einstein's Hamiltonian for the Gravitational Field?

  • Physicist97
  • · Replies 7 ·
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7

Undergrad What is the structure of a photon and can it be observed?

  • just curious
  • · Replies 7 ·
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7