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

Undergrad Cosmic Inflation Explained: Constant Velocity of Electromagnetic Radiation

  • JonathanMFreedman
  • · Replies 3 ·
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3

Graduate Relativistic Relative Velocity Comp.: Bini, D. et al. (1995)

  • More_anonymous
  • · Replies 9 ·
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9

High School Differences in Predictions between SR and LR?

  • alexandrinushka
  • · Replies 20 ·
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20

Undergrad Spacetime interval and basic properties of light

  • HansH
  • · Replies 141 ·
5
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141

Graduate Can discrete temporal symmetries exist in general relativity?

  • Tertius
  • · Replies 22 ·
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22

Undergrad Understanding Simultaneity Through Male & Female Clocks Meeting

  • Master Wayne
  • · Replies 12 ·
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12

Undergrad Karl Schwarzschild: Solving GR on the Eastern Front

  • BWV
  • · Replies 4 ·
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4

Undergrad Effect of Black Hole Spin on Gravity

  • BWV
  • · Replies 18 ·
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18

High School What Causes Mass to Exert Gravitational Pull?

  • Palasta
  • · Replies 1 ·
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1

Graduate Solving Equation 15.43 Line 2 to 3 in Tevian Dray's Differential Forms

  • gnnmartin
  • · Replies 4 ·
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4

Undergrad Spatially Homogeneous Scalar Field on Spacetime: Showing $\nabla^2 f$

  • ergospherical
  • · Replies 3 ·
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3

Graduate (paper) Stability properties of Kerr BH's

  • malawi_glenn
  • · Replies 12 ·
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12

Undergrad Being at the position of a singularity before it is formed

  • HansH
  • · Replies 84 ·
3
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84

High School Can gravitational time dilation explain the galaxy rotation curve?

  • sha1000
  • · Replies 11 ·
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11

Undergrad 4D d'Alembert Green's function for linearised metric

  • ergospherical
  • · Replies 4 ·
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4

High School Andy Weir's "Hail Mary": Question About Relativistic Rocket

  • GTOM
  • · Replies 13 ·
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13

High School Twin Paradox (3 objects version)

  • h1a8
  • · Replies 32 ·
2
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32

Undergrad Calculating Particle Redshift at Time t_0 & t_1

  • ergospherical
  • · Replies 6 ·
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6

Undergrad The Derivative Nature of Time and Its Relation to Earth's Rotation and Speed

  • sumfor
  • · Replies 38 ·
2
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38

Undergrad Follow Up on M. LeBellac & J.M. Levy-Leblond's "Galilean Electromagnetism

  • otennert
  • · Replies 17 ·
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17

Graduate What assumptions underly the Lorentz transformation?

  • Ad VanderVen
  • · Replies 120 ·
5
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120

Undergrad How is proper time visualized in the FLRW metric's 4D spacetime geometry?

  • Ennio
  • · Replies 6 ·
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6

Undergrad Only Minkowski or Galilei from Commutative Velocity Composition

  • Sagittarius A-Star
  • · Replies 1 ·
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1

Undergrad Gravity Wave Speed: Deriving Constancy from Maxwell Eqs.

  • Narasoma
  • · Replies 34 ·
2
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34

Undergrad Understanding Covariant and Partial Derivatives in General Relativity

  • GR191511
  • · Replies 5 ·
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5

Undergrad Lorentz Transformation Derivation: Assumptions Req'd?

  • Pencilvester
  • · Replies 5 ·
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5

High School Calculating Time Dilation w/ Light Clock - Implications & Mistakes?

  • rgtr
  • · Replies 4 ·
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4

High School Cosmic Inflation & Censorship: Validation or Corrections?

  • Le Tenie
  • · Replies 1 ·
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1

Undergrad What Happens Inside BH Event Horizon?

  • kochanskij
  • · Replies 7 ·
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7

Undergrad Calculating Relative Change in Travel Time Due to Spacetime Perturbation

  • cicero
  • · Replies 3 ·
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3

Undergrad Please help with my spacetime diagrams (relativity problem)

  • student34
  • · Replies 27 ·
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27

High School Time: What We Read On The Clock?

  • DanAil
  • · Replies 26 ·
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26

Undergrad Diagonal Matrix of Stress-Energy Tensor: Why?

  • GR191511
  • · Replies 17 ·
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17

Undergrad Why Does Covariant Index Represent Partial Derivative in Special Relativity?

  • GR191511
  • · Replies 22 ·
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22

Undergrad Conserved Quantity Along Affine Parameter

  • Dale
  • · Replies 8 ·
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8

Undergrad Light Clock Relativity: Why Divide T_moving/T_stationary?

  • rgtr
  • · Replies 15 ·
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15

Undergrad Question about Stress-Energy Tensor: A First Course in GR

  • GR191511
  • · Replies 8 ·
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8

Graduate Is Gravity Just the Electrostatic Force?

  • TruthSeeker777
  • · Replies 6 ·
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6

High School Can Particles Escape a Black Hole? The Hawking Radiation Improbability

  • pforeman
  • · Replies 3 ·
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3

Undergrad Uniform gravitational field possible in GR?

  • JandeWandelaar
  • · Replies 22 ·
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22

Graduate Connectedness of Boundary Points in Schwarzschild Penrose Chart

  • PeterDonis
  • · Replies 7 ·
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7

Undergrad Why do we still say “the speed of light” instead of “c”?

  • katakuri
  • · Replies 12 ·
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12

Undergrad Definition of "Physical Frame": All You Need To Know

  • Vincentius
  • · Replies 23 ·
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23

Undergrad Is the concept of a one-way speed of light meaningful and measurable?

  • Freixas
  • · Replies 25 ·
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25

High School Object Weight on Magnetar vs Neutron Star: Attract or Repel?

  • kuartus4
  • · Replies 8 ·
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8

Graduate Special Relativity Fiber Bundle: R^3 & Lorentz Metric

  • Thytanium
  • · Replies 10 ·
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10

Undergrad Speed of Light: Spaceship & Gravity Law Impact

  • abdossamad2003
  • · Replies 15 ·
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15

Undergrad Why is Number-Flux Four-Vector Frame-Independent?

  • GR191511
  • · Replies 4 ·
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4

Undergrad Velocity addition via k-calculus

  • pervect
  • · Replies 3 ·
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3

High School Penrose Diag Black Hole: Riddle Me This

  • sbaker8688
  • · Replies 24 ·
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24

Undergrad The Length of World Line: Prerequisite for Proper Time

  • GR191511
  • · Replies 4 ·
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4

Graduate Britgrav Weyl Tensor Research: Find Paper Authors, Title & Accessibility

  • gnnmartin
  • · Replies 2 ·
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2

Undergrad Why Is Minkowski Spacetime Non-Euclidean?

  • Trysse
  • · Replies 63 ·
3
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63

Undergrad Weak principle of equivalence (Galileo, Newton)

  • qnt200
  • · Replies 5 ·
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5

High School Does Mass Have Lasting Gravitational Effect Over Time?

  • kyle1320
  • · Replies 19 ·
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19

Undergrad The Theoretical Minimum: Length Contraction and Time Dilation

  • DavidBalut
  • · Replies 17 ·
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17

Graduate Units of Kerr Understanding Mass & Angular Momentum

  • swampwiz
  • · Replies 3 ·
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3

High School Free Fall in Curved Spacetime: Does Minkowski Spacetime Exist?

  • DanAil
  • · Replies 21 ·
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21

Undergrad Searching for "Why Is Minkowski Spacetime Non-Euclidean" by Cronkhite

  • Trysse
  • · Replies 14 ·
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14

Undergrad Constraints on Lorentz Velocity Transformation

  • alhuebel
  • · Replies 6 ·
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6

Undergrad Does Space Curvature Account for Gravity Between Individual Atoms?

  • Martyn Arthur
  • · Replies 2 ·
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2

Undergrad Can Maxwell's Equations Explain Gravitation Through Retarded Wave Solutions?

  • paige turner
  • · Replies 12 ·
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12

Graduate Schwarzschild Geometry: Evaluating Proper Distance

  • kirkr
  • · Replies 9 ·
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9

High School Orthogonality in Minkowski Spacetime: Meaning & Visualization

  • lindberg
  • · Replies 14 ·
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14

Undergrad Co-Moving Coordinates & Lapse Function N(t) in ADM Decomposition

  • Tertius
  • · Replies 8 ·
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8

Undergrad Will a spherical mass be set in motion by a spherical shell rotating around it?

  • JandeWandelaar
  • · Replies 36 ·
2
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36

High School Proving Reciprocity Of Time Dilation

  • DanAil
  • · Replies 44 ·
2
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44

Undergrad Applying Velocity Addition in Rotating Frame: Is It Correct?

  • lindberg
  • · Replies 18 ·
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18

Undergrad Shape Dynamics: How Can It Offer Same Predictions as GR & SR?

  • lindberg
  • · Replies 14 ·
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14

Undergrad Questions concerning the geometry of spacetime

  • student34
  • · Replies 111 ·
4
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111

High School Can Black Hole Gravity Be Overpowered?

  • Picalilli
  • · Replies 9 ·
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9

Undergrad Relativistic Velocity Addition: Calculating Electron Speed

  • lindberg
  • · Replies 4 ·
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4

Undergrad Does the Light's One/Two-Way Speed Distinction Mean Anything?

  • Pony
  • · Replies 5 ·
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5

Undergrad Calculate Eigenvalues of Electromagnetic & Stress-Energy Tensors

  • ergospherical
  • · Replies 3 ·
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3

Graduate Worked examples Cartan Formalism

  • zwoodrow
  • · Replies 3 ·
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3

Graduate Relativistic Hydrodynamics Eqn for Perfect Fluid: Insight Needed

  • Bruno Cardin
  • · Replies 10 ·
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10

Undergrad Why am I getting the wrong conclusion from my spacetime diagram?

  • student34
  • · Replies 24 ·
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24

Undergrad Instrument Size & Wavelength: What's the Relationship?

  • accdd
  • · Replies 5 ·
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5

Undergrad Raising & Lowering Indices: Q&A on Relativity

  • GR191511
  • · Replies 5 ·
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5

High School Can a Planet Made of Glass Generate Free Energy?

  • Pony
  • · Replies 1 ·
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1

Undergrad Potential Energy in Wormholes: Charged Particles & Electric Fields

  • Haorong Wu
  • · Replies 4 ·
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4

High School Sagnac effect for matter beams

  • alexandrinushka
  • · Replies 40 ·
2
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40

Undergrad Is the Killer Crate Paradox Resolved?

  • Gamma Anon
  • · Replies 60 ·
3
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60

Undergrad Doppler Analysis of Twin Experiment: Valid Argument?

  • Kairos
  • · Replies 37 ·
2
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37

Undergrad How Can Outward Normal Vector Point Inwards?

  • GR191511
  • · Replies 17 ·
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17

Undergrad Einstein Definition of Simultaneity for Langevin Observers

  • cianfa72
  • · Replies 11 ·
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11

Undergrad Infinite Frequencies & Extraterrestrial Signals: What Are We Missing?

  • Spockishere
  • · Replies 18 ·
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18

Undergrad The Units of the Cosmological Constant: eV^2

  • Safinaz
  • · Replies 4 ·
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4

Undergrad Simulating GR: Worth the Effort?

  • accdd
  • · Replies 4 ·
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4

Undergrad Fermi-Walker Transport: History & 1932 Paper

  • facenian
  • · Replies 6 ·
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6

High School Time Dilation & Muon De Broglie Wavelength: Explained

  • bobdavis
  • · Replies 27 ·
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27

High School What Does Hawking Mean by Negative Energy at the Big Bang?

  • Physics Slayer
  • · Replies 1 ·
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1

High School Parallel light reflection for a one-way speed of light measurement setup

  • OWSOL
  • · Replies 45 ·
2
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45

Undergrad Kronecker Delta: Order of Indices Explained

  • Jim Lai
  • · Replies 5 ·
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5

High School Travel 7 Light Years at 50000km/s - How Long?

  • Spockishere
  • · Replies 12 ·
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12

Undergrad Is Time Dilation Just a Misunderstanding of Clock Errors?

  • paul1365
  • · Replies 4 ·
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4

High School Time Dilation on Rotating Disk: Clocks on Disk Perspective

  • Thadriel
  • · Replies 21 ·
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21

High School General Relativity & Ether: Clarifying a Contradiction?

  • DanAil
  • · Replies 18 ·
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18

Graduate Curvature & Connection Without Metric

  • pervect
  • · Replies 1 ·
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1

Undergrad Energy Density in E Field: Does it Contribute to Inertial Mass?

  • Will Learn
  • · Replies 16 ·
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16