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 Michelson-Morley: Errors in Calculations?

  • vchal
  • · Replies 6 ·
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6

Undergrad Can circular polarizers generate wormholes and warp drives?

  • sddfds
  • · Replies 12 ·
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12

Undergrad How do you contract the 2nd and 4th indices of the Riemann tensor?

  • GR191511
  • · Replies 24 ·
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24

High School Does Force Travel Faster Than Light?

  • MrSimp
  • · Replies 8 ·
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8

High School Does the gravitational time dilation factor have a name?

  • IXWELL
  • · Replies 2 ·
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2

Undergrad Matter Gaining Energy from Expanding Spacetime?

  • Suekdccia
  • · Replies 7 ·
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7

Undergrad Are locally flat and locally inertial frames equivalent?

  • GR191511
  • · Replies 33 ·
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33

Undergrad Does Special and General Relativity Affect Aging of Apollo Astronauts?

  • PeterDonis
  • · Replies 10 ·
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10

High School Does separating two masses increase system mass via gravitational binding energy?

  • andrew s 1905
  • · Replies 4 ·
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4

Undergrad Calculate Gaussian Curvature from 4D Metric Tensor

  • Sciencemaster
  • · Replies 14 ·
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14

High School Do high frequency photons bend more in gravity?

  • mdeng
  • · Replies 10 ·
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10

Undergrad Does the speed of light vary with the energy-to-mass ratio in the universe?

  • 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 How do moving clocks stay synchronized if light reaches them at different times?

  • 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 Why does a relativistic rocket need less fuel in Hail Mary?

  • 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 Particle velocity relation in FLRW spacetime

  • 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 Galilean electromagnetism in LeBellac and Levy-Leblond (1973)

  • 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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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 Are cosmic inflation and cosmic censorship still being corrected or validated?

  • 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 Why does an event appear far away in Object B's rest frame spacetime diagram?

  • student34
  • · Replies 27 ·
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27

High School What does Einstein mean by time is what we read on the clock?

  • DanAil
  • · Replies 26 ·
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26

Undergrad Why must a diagonal stress-energy tensor be a multiple of the identity?

  • 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 Why is time dilation a ratio, not a difference?

  • rgtr
  • · Replies 15 ·
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15

Undergrad When are off-diagonal stress-energy tensor components zero?

  • 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 What is a physical frame in cosmology?

  • 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 Can spacetime be modeled as a fiber bundle with time as base and R^3 fibers?

  • Thytanium
  • · Replies 10 ·
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10

Undergrad Does a spaceship at relativistic speed increase gravitational effects?

  • 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 Why does the event horizon tilt 45 degrees on Penrose diagrams?

  • 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 Finding a Britgrav paper on rotating spacetime with Weyl tensor waves

  • 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 Why does a leg exceed the hypotenuse in spacetime diagrams?

  • DavidBalut
  • · Replies 17 ·
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17

Graduate Why does M⁴ > J² work dimensionally in Kerr solution?

  • swampwiz
  • · Replies 3 ·
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3

High School Does Minkowski spacetime actually exist in the real universe?

  • 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 What does orthogonality between time and space mean in non-inertial frames?

  • lindberg
  • · Replies 14 ·
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14

Undergrad Why is co-moving coordinates always possible 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 Can you use relativistic velocity addition on a rotating disk rim?

  • lindberg
  • · Replies 18 ·
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18

Undergrad How can Shape Dynamics match GR and SR predictions without time or simultaneity?

  • 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 How to find eigenvalues of the electromagnetic and 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 Extra term in the relativistic Euler equation for fluids

  • 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 Minkowski metric index notation in Lorentz transformations

  • 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 Do charged particles gain or lose kinetic energy through wormholes?

  • 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 Does the Doppler shift argument resolve the twin paradox?

  • 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 Could extraterrestrial signals be on frequencies we can't detect?

  • 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