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 Einstein Field Equations, how many?

  • Igorr
  • · Replies 22 ·
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22

Graduate Breakdown of Correspondence Principle: Null Dust Case

  • victorvmotti
  • · Replies 5 ·
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5

Graduate Interplay of space and time in Spacetime invariant interval

  • Ittiandro
  • · Replies 44 ·
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Graduate Phase Velocity Definition: A or B?

  • Helios
  • · Replies 12 ·
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12

Graduate Help Understanding Simultaneity Diagram

  • xDk
  • · Replies 10 ·
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10

Graduate Perception & Relativity: Near-Light Speed Travel

  • udtsith
  • · Replies 7 ·
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7

Undergrad How the standard spacetime model relates to reality

  • name123
  • · Replies 33 ·
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33

Graduate Who Hits Wall First: Light Beam or Light Traveller?

  • aboro
  • · Replies 5 ·
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5

Graduate Mirror Reflection of a Wave: Analyzing the Outgoing Wave

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

  • name123
  • · Replies 7 ·
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7

Graduate Solve the Special Theory of Relativity Confusion

  • Shehreyar Khan
  • · Replies 4 ·
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4

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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2

Undergrad Why does time link gravity and masslessness?

  • toastercombo
  • · Replies 27 ·
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27

Graduate Light Beam Opposite Motion: Einstein Special Theory

  • MZaeemQ
  • · Replies 3 ·
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3

Graduate Time as a dimension, can spatial length be applied to it?

  • mcjosep
  • · Replies 11 ·
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11

Graduate Gravitational Time Dilation & Orbits of Objects

  • Warfen
  • · Replies 4 ·
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4

Graduate On the usual confusion among what it is and what is measure

  • MachPrincipe
  • · Replies 9 ·
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9

Graduate Flat Universe as Torus: Legit Research & Solutions?

  • Zeno Marx
  • · Replies 1 ·
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1

Graduate Confused about the logic of a Special Relativity problem

  • Nantes
  • · Replies 66 ·
3
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66

Graduate Producing a metric with only a single coordinate function

  • grav-universe
  • · Replies 25 ·
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25

Undergrad Relativity of simultaneity, understood, now not so sure.

  • DAC
  • · Replies 12 ·
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12

Graduate What Are the Key Effects of Special Relativity on Time and Mass?

  • fog37
  • · Replies 3 ·
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3

Graduate Electromagnetic Tensor in (-+++) Convention

  • tomdodd4598
  • · Replies 3 ·
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3

Graduate Lorentz Transformation Equation Paradox

  • Rahul Mohan P
  • · Replies 8 ·
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8

High School Lorentz Transformation Equation Paradox - Find Where I Went Wrong

  • Rahul Mohan P
  • · Replies 2 ·
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2

High School FTL Paradox: Grandfather Paradox Explained

  • MysticWizard
  • · Replies 1 ·
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1

Graduate Shape of Space-Time: Warping Explained

  • Fuinne
  • · Replies 4 ·
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4

Graduate Do Moving Objects Return to Original Length After Stopping?

  • Ut-Napishtim
  • · Replies 29 ·
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29

Graduate General vectors and tangent space

  • sunrah
  • · Replies 6 ·
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6

Graduate Question on Einstein original paper

  • DrSirius
  • · Replies 6 ·
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6

Graduate Is Gravity a Physical Entity Like Light Waves?

  • Fuinne
  • · Replies 3 ·
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3

Graduate Assuming Lorentz transform is affine

  • Erland
  • · Replies 26 ·
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26

Graduate Analog of Gauss' law in gravity

  • LagrangeEuler
  • · Replies 2 ·
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2

Graduate Can the Dot Product of Four Vectors Maintain Positive Component Signs?

  • tomdodd4598
  • · Replies 9 ·
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9

Graduate Intergalactic Space & the Minkowski Diagram

  • DiracPool
  • · Replies 14 ·
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14

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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3

Graduate Define Mass: Travels Through Time?

  • toastercombo
  • · Replies 2 ·
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2

Graduate Is There a Hidden Meaning in Integrating the Lorentz Factor with Trig Sub?

  • Astro Boy 327
  • · Replies 2 ·
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2

Graduate Can a "density" of points create curvature?

  • friend
  • · Replies 4 ·
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4

Undergrad Lorentz Transformations or Dilation/Contraction?

  • NiallBucks
  • · Replies 23 ·
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23

Graduate Are length and time Trade-offs in relativity?

  • Dopplershift
  • · Replies 10 ·
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10

Graduate Null geodesic definition (by extremisation?)

  • cesiumfrog
  • · Replies 18 ·
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18

Graduate Independent Killing vector field

  • astrolollo
  • · Replies 3 ·
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3

Graduate Questions of Absolute Light Speed & Mass by an Engineer

  • nandodean
  • · Replies 14 ·
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14

Graduate Question about relativity of simultaneity

  • AlonsoMcLaren
  • · Replies 10 ·
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10

Graduate Does the photon have a 4-velocity in a medium?

  • PFfan01
  • · Replies 82 ·
3
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Graduate Unbounded perturbed geometry due to analyticity

  • CharlesJQuarra
  • · Replies 2 ·
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2

Graduate Statistical Mechanics in GR: Basics & Applications

  • andresB
  • · Replies 15 ·
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15

Undergrad Hyper-Light Speed: What Happens?

  • 5P@N
  • · Replies 4 ·
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4

Graduate Is There More to Special Relativity?

  • arydberg
  • · Replies 6 ·
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6

Graduate Principle of relativity and invariance of c

  • Jose Leal
  • · Replies 1 ·
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1

High School Why is gravitational force always attractive in nature?

  • preitiey
  • · Replies 17 ·
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17

Graduate Speed of Light Since Big Bang: Evidence & Theory

  • Bharath Siva
  • · Replies 2 ·
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2

Graduate Understanding Vaidya Metric & Pure Radiation Stress-Energy

  • victorvmotti
  • · Replies 3 ·
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3

Graduate Is Time Dilation Misunderstood in Popular Science Videos?

  • seb7
  • · Replies 77 ·
3
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77

Graduate Find Perfect Fluid & EM Tensor in Rest Frame

  • victorvmotti
  • · Replies 6 ·
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6

Graduate Why a vector field can not be used to describe gravity?

  • Chhhiral
  • · Replies 9 ·
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9

Graduate Length Contraction & Galaxies: Time Dilation Adjustments

  • vinven7
  • · Replies 8 ·
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8

Graduate Could Length Contraction Provide Insights into Quantum Entanglement Paradoxes?

  • peety
  • · Replies 2 ·
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2

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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4

Graduate Looking for sources for deprecation of relativistic mass

  • MachPrincipe
  • · Replies 8 ·
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8

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 ·
2
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34

Graduate Time Dilation at ISCO for Kerr Black Holes

  • Neutrinos02
  • · Replies 2 ·
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2

Graduate Time in Relativity & Quantum Mechanics: A Philosophical Perspective

  • black hole 123
  • · Replies 3 ·
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3

Graduate Ergoregions and Energy Extraction

  • adsquestion
  • · Replies 36 ·
2
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36

Undergrad What's the fate of neutrons in black hole formation?

  • Aliasa
  • · Replies 23 ·
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23

High School Randall Munroe Explains General Relativity

  • Ygggdrasil
  • · Replies 20 ·
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20

Undergrad Relativistic Doppler Effect: Explaining the Equation

  • I'mnotarobot
  • · Replies 7 ·
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7

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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2

Graduate What is the difference between Boost and Translation?

  • suvendu
  • · Replies 10 ·
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10

Graduate Does the Circular Twin Paradox Challenge Our Understanding of Time Dilation?

  • 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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13

Undergrad Diffraction Redshift and Emission Theory

  • greswd
  • · Replies 3 ·
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3

Graduate Time & The Special Theory of Relativity

  • Ameer Bux
  • · Replies 7 ·
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7

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 Speed of Light & Thought Exp: How to Send Info 186K Miles Instantly

  • Stig Ramone
  • · Replies 1 ·
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1

Graduate Question about Purcell - Electricity and Magnetism

  • 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

Graduate Unpredictable Outcomes: What Happens When Falling into a Black Hole?

  • Grogbor
  • · Replies 8 ·
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8

Graduate Singularity Theorems: An Accessible Reference

  • jinawee
  • · Replies 3 ·
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3

Graduate Does temperature in special relativity depend on the frame of observation?

  • Ravyan Asro
  • · Replies 8 ·
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8

Graduate Time Travel: How Far & Fast to Reach Alien Neighbors?

  • Saerryan89
  • · Replies 4 ·
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4

High School Deriving GR without EFE: Could it be this Simple?

  • grav-universe
  • · Replies 1 ·
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1

Graduate Observer Falling Into a Black Hole -- What do they see?

  • valentin mano
  • · Replies 16 ·
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16

Graduate Faster Than Light Communication Through Space-Time Bubbles

  • Teslanumber1
  • · Replies 2 ·
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2

Graduate Ergosphere and angular velocity

  • Neutrinos02
  • · Replies 20 ·
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20

Graduate Proof than an equation is Lorentz invariant

  • spaghetti3451
  • · Replies 8 ·
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8

Undergrad Theory of Relativity & Gravity: Is Space Pushing Us to Earth?

  • CollinsArg
  • · Replies 3 ·
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3