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

High School Questions about Einstein and the Block Universe

  • Quantum Alchemy
  • · Replies 1 ·
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1

High School Matter & Spacetime: How Tightly Coupled Are They?

  • kfielder
  • · Replies 16 ·
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16

Undergrad Is there a complete list of exact stationary solutions to Einstein's field equations?

  • Creedence
  • · Replies 8 ·
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8

Undergrad Realistic Time Dilation for Objects > Subatomic Particles

  • dsaun777
  • · Replies 10 ·
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10

Undergrad Why do relativistic effects let us reach distant galaxies faster than light seems to?

  • SpookyAction_
  • · Replies 2 ·
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2

Undergrad Faster Than Light Particle: Could it Create the Universe?

  • Mike Downey
  • · Replies 3 ·
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3

High School Speed of Light: Michelson-Morley Experiment Revisited

  • x-vision
  • · Replies 9 ·
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9

Undergrad Do observers at different locations measure different fall times?

  • adosar
  • · Replies 3 ·
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3

Undergrad Usefulness of Diagrams for Relativity: 1-5

  • kent davidge
  • · Replies 7 ·
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7

Undergrad Visualizing geodesics of falling bodies around Earth

  • bland
  • · Replies 4 ·
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4

Undergrad Relativistic centrifugal force

  • Alan McIntire
  • · Replies 59 ·
2
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59

High School Gravitational Effects on Aging

  • Benfield
  • · Replies 13 ·
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13

Undergrad How do you add velocities at an angle?

  • Myslius
  • · Replies 8 ·
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8

High School Does Dark Energy Explain the Expansion of Space in Relativity?

  • Sachabloke
  • · Replies 4 ·
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4

Undergrad Unknown velocity vector of a rail carraige

  • RossBlenkinsop
  • · Replies 12 ·
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12

Graduate What does the notation g_μν,αβ mean and why can't it vanish in curved spacetime?

  • berlinspeed
  • · Replies 10 ·
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10

Undergrad Proper vs. coordinate acceleration

  • bob012345
  • · Replies 37 ·
2
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37

Undergrad Hubble's Law and Star Velocity

  • Gege01
  • · Replies 40 ·
2
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40

Graduate Deriving 4-velocity components from proper time

  • berlinspeed
  • · Replies 6 ·
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6

High School Gravity -- a force or a cause of a force?

  • zanick
  • · Replies 16 ·
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16

Undergrad Deriving tensor transformation laws

  • Daniel_C
  • · Replies 3 ·
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3

Undergrad How Does Time Dilation Affect Space Travel Duration?

  • Arman777
  • · Replies 7 ·
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7

High School Attribution of Reference Frame: A Dilettante's Question

  • SteveF
  • · Replies 5 ·
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5

Undergrad How many ways can the Lorentz transformations be derived?

  • kent davidge
  • · Replies 28 ·
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28

Graduate Understanding gravitational waves (GR)

  • JD_PM
  • · Replies 43 ·
2
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43

Graduate Solve for "conv" in ##x^0=t=ct_{conv}##

  • berlinspeed
  • · Replies 2 ·
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2

Undergrad Clock synchronisation in a circular rotating train frame

  • Foppe Hoekstra
  • · Replies 32 ·
2
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32

High School Confirm General Relativity: Eddington's Starlight Experiment

  • Bob R
  • · Replies 4 ·
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4

High School Why is E=MC2 Squared and not Cubed?

  • Trooper149
  • · Replies 7 ·
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7

High School Why Does Proper Time in Lorentz Geometry Use t²-x² Instead of t²+x²?

  • berlinspeed
  • · Replies 15 ·
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15

Undergrad Why 3-momenta + lorentz invariance = large energy?

  • lucas_
  • · Replies 10 ·
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10

High School Can a warp bubble moving at 10c avoid a black hole's event horizon?

  • bob012345
  • · Replies 7 ·
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7

High School Doppler Effect: Light Blueshifted When Source Moving Towards Observer

  • kent davidge
  • · Replies 5 ·
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5

Undergrad Gravitational Mass of a Ball of Photons: Concept Q10.4 in Gen Relativity

  • PeterDonis
  • · Replies 7 ·
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7

High School Does mass curving spacetime mean it curves into a 5th dimension?

  • diazdaiz
  • · Replies 4 ·
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4

Undergrad Does absorbing a photon increase the electron's mass?

  • dsaun777
  • · Replies 8 ·
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8

Undergrad Is the Alcubierre Warp Drive possible?

  • swampwiz
  • · Replies 82 ·
3
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82

Undergrad Why can't accelerator particles exceed the speed of light?

  • Chemong
  • · Replies 18 ·
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18

High School Does the traveling twin in the twin paradox age less?

  • Buckethead
  • · Replies 208 ·
7
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208

High School Curve Space-time from Spinning disc?

  • lucas_
  • · Replies 49 ·
2
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49

Undergrad Deciphering the Units of Continuity Equation in GR

  • dsaun777
  • · Replies 23 ·
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23

High School Applicability of GR in Tidal Gravity Problems?

  • metastable
  • · Replies 14 ·
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14

Undergrad Does expansion redshift affect time dilation like ordinary motion?

  • DuckAmuck
  • · Replies 10 ·
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10

Undergrad Is Space-Time Continuous or Quantized?

  • GregoryC
  • · Replies 10 ·
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10

Graduate Semicolon notation in component of covariant derivative

  • berlinspeed
  • · Replies 5 ·
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5

High School Is Time Really Flowing in Relativity?

  • TheQuestionGuy14
  • · Replies 2 ·
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2

Graduate Dimensional analysis of E=mc²: is this reasoning valid?

  • JSHD2019
  • · Replies 7 ·
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7

Insights The Einstein Field Equation in a Static, Spherically Symmetric Spacetime

  • PeterDonis
  • · Replies 23 ·
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23

High School Does rotation have absolute status in Mach's principle?

  • Alfredo Tifi
  • · Replies 6 ·
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6

Graduate How Do You Derive the Riemann Component?

  • berlinspeed
  • · Replies 2 ·
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2

Graduate Can inner regions of black holes emit Hawking radiation?

  • PSR1257II
  • · Replies 7 ·
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7

Undergrad Adding Extra Dimension for Calculations in Curved Spaces

  • Kairos
  • · Replies 5 ·
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5

High School Is There Evidence of Physical Matter Existing Beyond the Present Moment?

  • David W Thomson
  • · Replies 21 ·
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21

Graduate How is the Riemann tensor component form derived?

  • berlinspeed
  • · Replies 2 ·
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2

High School Is the case for a Universal Speed Limit experimental or theoretical?

  • geordief
  • · Replies 41 ·
2
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41

High School Why do gravitational waves escape black holes but electromagnetic waves don't?

  • Raffaele
  • · Replies 5 ·
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5

High School Length contraction of a pair of electrons

  • DaveC426913
  • · Replies 54 ·
2
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54

Undergrad Approximating a Black Hole Merger Using a Schwarzschild Model

  • BlackWhole
  • · Replies 1 ·
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1

Undergrad Binding Mass Distribution in Gravitating Bodies

  • zonde
  • · Replies 13 ·
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13

High School How does GR predict Earth's orbit around the sun?

  • Bob R
  • · Replies 7 ·
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7

Graduate Gravity on Planets: Does Mass Affect Free Fall?

  • Sciolo
  • · Replies 4 ·
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4

Undergrad Inverse results in special relativity

  • Kairos
  • · Replies 30 ·
2
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30

Undergrad What is the experience of a photon?

  • Brian Preece
  • · Replies 4 ·
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4

Undergrad Solving the HUGE Issue with Lorentz Transformations and Lightning Strikes

  • JMart12
  • · Replies 7 ·
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7

Undergrad General Lorentz transformation with arbitrary relative motion direction

  • Sang-Hyeon Han
  • · Replies 1 ·
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1

Undergrad Two Observers Moving Opposite Dir Rel to Each Other

  • Sang-Hyeon Han
  • · Replies 5 ·
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5

Undergrad The Singularity and the Schwarzschild radius

  • stg213
  • · Replies 25 ·
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25

Undergrad Why Are Coordinates in General Relativity Independent?

  • TomServo
  • · Replies 7 ·
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7

High School Professional debates about Spacetime

  • lucas_
  • · Replies 39 ·
2
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39

High School Total % of Photons Redshifted While Moving Away From a Black Hole?

  • metastable
  • · Replies 53 ·
2
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53

Undergrad Length contraction viewed with Heaviside equations

  • learn.steadfast
  • · Replies 42 ·
2
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42

Graduate Is Time Constant Across the Universe or Does it Change Over Billions of Years?

  • Ed Slade
  • · Replies 1 ·
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1

Undergrad Why Is the Green Observer Always the Bent One in the Twin Paradox?

  • SamRoss
  • · Replies 106 ·
4
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106

Undergrad Do ##\vec E## and ##\vec B## change in a moving frame?

  • JD_PM
  • · Replies 49 ·
2
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49

High School Measuring Fictitious Forces in a Closed Box

  • metastable
  • · Replies 16 ·
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16

Undergrad Spacetime and Events in (x,y,z,t)

  • RossBlenkinsop
  • · Replies 11 ·
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11

High School When do inertial and gravitational mass differ?

  • jeremyfiennes
  • · Replies 18 ·
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18

Undergrad Electromagnetic Fields and the manipulation of Space-Time

  • Dinoduck94
  • · Replies 9 ·
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9

Undergrad Does retro-causal entanglement violate special relativity?

  • exmarine
  • · Replies 52 ·
2
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52

Undergrad How Do Rockets Traveling at High Speeds Observe Each Other's Velocity?

  • some bloke
  • · Replies 6 ·
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6

Undergrad The velocity of a moving frame of reference

  • RossBlenkinsop
  • · Replies 111 ·
4
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111

Undergrad Alternative form of geodesic equation for calculating Christoffels

  • Jason Bennett
  • · Replies 1 ·
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1

Undergrad Is it possible to have synchronized clocks in a rotating system?

  • Foppe Hoekstra
  • · Replies 55 ·
2
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55

High School Can I keep multiple clocks in sync after a ride on a roller coaster?

  • metastable
  • · Replies 17 ·
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17

Undergrad Question regarding the nature of mass inside a black hole

  • Buzz Bloom
  • · Replies 39 ·
2
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39

High School Rest Energy and a 1 million solar mass black hole

  • metastable
  • · Replies 48 ·
2
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48

Undergrad Can an object fall into a black hole at faster that the speed of light?

  • Herbascious J
  • · Replies 7 ·
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7

Undergrad What does proper radius mean in the Schwarzschild metric?

  • kelly0303
  • · Replies 7 ·
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7

Undergrad Do clocks on Bell’s spaceships stay synchronized?

  • Foppe Hoekstra
  • · Replies 27 ·
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27

Undergrad Why is ∂xk/∂x'h = Rhk and not Rkh in Zee's tensor notation?

  • Noobnoob
  • · Replies 14 ·
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14

Undergrad Space-Like Hypersurface: Simultaneous Events?

  • Apashanka
  • · Replies 2 ·
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2

High School Does my speedy spaceship (.999+C) have a temperature?

  • Suppaman
  • · Replies 31 ·
2
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31

Undergrad Special Relativity: Train in Tunnel Paradox Solved

  • Agalal1
  • · Replies 6 ·
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6

High School Can Canceling Orbital Motion Improve Rocket Efficiency?

  • metastable
  • · Replies 90 ·
4
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90

Undergrad Covariant derivative of the contracted energy-momentum tensor of a particle

  • sergiokapone
  • · Replies 22 ·
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22

Graduate Do Moving Masses Slow Down Due to Gravitational Waves?

  • Cato
  • · Replies 5 ·
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5

High School Train platform -- light speed and time quandry

  • uniqueland
  • · Replies 14 ·
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14

Undergrad Is there a solution for the behavioural contradiction in RT?

  • Foppe Hoekstra
  • · Replies 35 ·
2
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35

Undergrad Measuring Mass of a Bowling Ball Dropped into a Black Hole

  • Herbascious J
  • · Replies 31 ·
2
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31

High School What happens if a photon has wavelength at the Planck length?

  • negativzero
  • · Replies 7 ·
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7