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 Mathematical problem with Schwarzschild spacetime?

  • Bosko
  • · Replies 26 ·
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26

High School Gravitational potential energy, a thought experiment

  • Lok
  • · Replies 125 ·
5
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125

High School Ship traveling near light speed arriving ahead of its own light

  • Somoth Ergai
  • · Replies 98 ·
4
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98

Undergrad Dirac comment on covariant derivatives

  • Kostik
  • · Replies 7 ·
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7

Undergrad Deriving the relativistic rocket equation with exhaust efficiency

  • halcyon_zomboid
  • · Replies 1 ·
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1

Undergrad Lorentz Transformations Confusion

  • laser
  • · Replies 14 ·
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14

High School Does the age of the Universe differ for observers in expanding space?

  • mister i
  • · Replies 19 ·
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19

Undergrad Newton Galilean spacetime as fiber bundle

  • cianfa72
  • · Replies 29 ·
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29

Graduate Coupling torsion to electromagnetism and torsion tensor decomposition

  • nicopa
  • · Replies 5 ·
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5

Undergrad Galaxy recession and Universe expansion

  • cianfa72
  • · Replies 90 ·
4
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90

Undergrad Is momentum conserved as a body falls through a gravitational field?

  • Herbascious J
  • · Replies 35 ·
2
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35

Undergrad Does Kerr's argument against singularities apply to all black holes?

  • Suekdccia
  • · Replies 12 ·
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12

Undergrad Doppler and Searchlight (Headlight)

  • Albertgauss
  • · Replies 21 ·
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21

Undergrad Difference between the Shapiro Delay and time dilation?

  • dsaun777
  • · Replies 1 ·
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1

Undergrad Is the electromagnetic 4-vector indeed a 4-vector?

  • mbond
  • · Replies 33 ·
2
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33

Undergrad Is Relativistic Action for a beam of light = zero?

  • LarryS
  • · Replies 5 ·
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5

Undergrad Spacetime expansion - time dimension expansion

  • exander
  • · Replies 48 ·
2
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48

Undergrad Perceive Length Contraction VS Terrell Penrose

  • Albertgauss
  • · Replies 14 ·
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14

Undergrad Light clock running faster than light?

  • tagehedin
  • · Replies 4 ·
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4

Undergrad Time dilation vs Differential aging vs Redshift

  • cianfa72
  • · Replies 21 ·
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21

High School Why Does Black Hole Entropy and Information Loss Matter?

  • Omega0
  • · Replies 7 ·
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7

Undergrad Why does length contraction only occur along the direction of motion?

  • Chenkel
  • · Replies 45 ·
2
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45

Undergrad Teaching Minkowski diagrams effectively

  • pervect
  • · Replies 15 ·
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15

Graduate Can We Construct a Coordinate Chart Where Bell Observers Are At Rest?

  • PeterDonis
  • · Replies 11 ·
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11

High School Could you use LIGO-technology to measure gravitational redshift?

  • Isambard
  • · Replies 11 ·
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11

Undergrad Why "time part" represents energy in Four-momentum?

  • PLAGUE
  • · Replies 6 ·
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6

Undergrad How do you resolve seeming contradictions in SR?

  • curiousburke
  • · Replies 76 ·
3
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76

High School Time dilation between moving observers in special relativity

  • joshuadeepak
  • · Replies 10 ·
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10

Undergrad Proof of Invariance of Spacetime Interval

  • PLAGUE
  • · Replies 6 ·
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6

High School What do people mean when they say “space is flat?”

  • BadgerBadger92
  • · Replies 8 ·
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8

Undergrad Potential energy and the gravitational field of a collapsing cloud of gas

  • Herbascious J
  • · Replies 1 ·
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1

Undergrad Curved spacetime bulging in time direction

  • pahenning
  • · Replies 30 ·
2
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30

High School Gravitational Time Dilation Inside the Sun

  • Mikael17
  • · Replies 9 ·
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9

High School General Relativity and Universal Gravitational Constant

  • ktmsud
  • · Replies 27 ·
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27

High School Can odometer analogy detect which starship is moving?

  • FIL
  • · Replies 34 ·
2
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34

Undergrad Why doesn't length contraction affect the charge count in moving vs stationary rods?

  • abdossamad2003
  • · Replies 3 ·
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3

High School How to add an object's multiple relativistic speeds from x, y, and z?

  • syfry
  • · Replies 37 ·
2
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37

Undergrad Can you distinguish gravity from acceleration if the accelerating mass affects gravity?

  • Kuruwee
  • · Replies 29 ·
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29

Undergrad Why doesn't relativity of simultaneity lead to a contradiction?

  • m082844
  • · Replies 17 ·
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17

Undergrad How Does Distance to Proxima Centauri Affect Simultaneous Events?

  • Ben S
  • · Replies 2 ·
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2

Undergrad Energy conservation in general relativity

  • KleinMoretti
  • · Replies 12 ·
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12

Graduate Tom Roberts updated the SR experiments FAQ section

  • jtbell
  • · Replies 3 ·
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3

Undergrad Speed of light after exiting a transparent medium

  • isotherm
  • · Replies 17 ·
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17

Undergrad Is the Lorentz transformation the unique way to preserve light speed invariance?

  • msumm21
  • · Replies 20 ·
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20

Undergrad Explaining time dilation and length contraction to skeptics

  • pellis
  • · Replies 61 ·
3
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61

High School What is m in Kinetic Energy? Relativistic mass or Rest mass?

  • Slimy0233
  • · Replies 55 ·
2
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55

Undergrad Seeing history when crossing event horizon

  • Hill
  • · Replies 41 ·
2
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41

High School Can we see 2 black holes orbiting each other?

  • HansH
  • · Replies 57 ·
2
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57

High School Does Space Recover or Oscillate After Being Distorted by Massive Objects?

  • pforeman
  • · Replies 3 ·
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3

High School Black hole electromagnetic spectrum

  • snorkack
  • · Replies 4 ·
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4

Undergrad Are the Lorentz Transformations False?

  • Leepappas
  • · Replies 54 ·
2
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54

Undergrad Can someone falsify this analogy contradicting time dilation?

  • misterously
  • · Replies 25 ·
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25

High School Does gravitational force act on system or its components?

  • jovi2k
  • · Replies 5 ·
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5

High School Where does the light energy lost due to expansion go?

  • mister i
  • · Replies 13 ·
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13

Undergrad What causes time dilation and length contraction

  • hababsbshshhs
  • · Replies 10 ·
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10

High School A thought experiment regarding special relativity

  • KyriakosTsp
  • · Replies 15 ·
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15

Undergrad Is the Idea of a Continuum Always an Approximation to the Physical?

  • walkeraj
  • · Replies 5 ·
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5

Undergrad Incomplete geodesics in a singularity, do they warrant quantum concerns?

  • walkeraj
  • · Replies 3 ·
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3

High School Would We See the Same Light After Traveling Back to Earth Faster Than Light?

  • markterry
  • · Replies 2 ·
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2

Undergrad Physical meaning of zero time metric

  • madsmh
  • · Replies 10 ·
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10

Graduate Do Black Holes have Singularities?

  • fresh_42
  • · Replies 20 ·
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20

Undergrad Tidal effects on event horizon of binary rotating BHs

  • Christian Thom
  • · Replies 6 ·
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6

Undergrad EFE with cosmological constant

  • grav-universe
  • · Replies 7 ·
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7

Undergrad Why does time dilation appear reversed in the full Lorentz transformation?

  • Chenkel
  • · Replies 101 ·
4
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101

High School Black hole evaporation mechanism

  • Gingerot
  • · Replies 4 ·
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4

Undergrad How Can You Approach Steve Without Being Doppler-Shifted?

  • jcsd
  • · Replies 4 ·
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4

High School Spacetime interval question involving a Pendulum in a Space Ship

  • Chenkel
  • · Replies 7 ·
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7

Undergrad What was the role of frequency in the Michelson-Morley experiment's null result?

  • MrYes
  • · Replies 3 ·
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3

Graduate Is there a basic example that works based on gravitoelectromagnetism?

  • sergioperezf
  • · Replies 9 ·
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9

High School Is the Accelerating Expansion of the Universe Wasting Energy?

  • mister i
  • · Replies 4 ·
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4

Undergrad Does Light Travel the Shortest Path in Curved Space-Time Around a Neutron Star?

  • Bosko
  • · Replies 82 ·
3
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82

High School What Are the Relativistic Implications for Beacon Synchronization?

  • dom_quixote
  • · Replies 25 ·
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25

Undergrad Isn't the speed of light tautologically 299792458 m/s?

  • Kekkuli
  • · Replies 34 ·
2
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34

High School Time dilation geometry in Morin's treatment of moving clocks

  • Chenkel
  • · Replies 73 ·
3
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73

Undergrad The speed of one photon through a transparent medium

  • isotherm
  • · Replies 74 ·
3
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74

Graduate Correspondence between areal radius differences and proper distances

  • PAllen
  • · Replies 4 ·
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4

Undergrad What is Earth's escape velocity?

  • binis
  • · Replies 8 ·
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8

Graduate How to Express the Schwarzschild Metric in Fermi Normal Coordinates?

  • Gleeson
  • · Replies 13 ·
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13

Undergrad Time dilation for a light pulse from Mars observed by a spaceship at 0.985c

  • dirac26
  • · Replies 14 ·
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14

High School How do you project a Killing Vector onto a Schwarzschild field?

  • bobrubino
  • · Replies 6 ·
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6

Undergrad Object accelerating away then stopping near a black hole event horizon

  • Ivo Draschkow
  • · Replies 35 ·
2
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35

Undergrad How Does Special Relativity Affect Perceived Distances Between Planets?

  • dwspacetime
  • · Replies 101 ·
4
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101

Undergrad Invariant definition of acceleration in Newtonian physics vs proper acceleration in GR

  • cianfa72
  • · Replies 30 ·
2
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30

Undergrad Interpretation of (X,T) coordinates in Kruskal diagram

  • Hill
  • · Replies 34 ·
2
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34

High School Is imaginary time a fourth dimension?

  • bobrubino
  • · Replies 13 ·
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13

High School Minkowski Spacetime vs Euclidean Spacetime

  • bobrubino
  • · Replies 11 ·
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11

High School Stationary charge next to a current-carrying wire

  • lightlightsup
  • · Replies 68 ·
3
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68

Undergrad What happens if you place a mirror behind an event horizon?

  • Bosko
  • · Replies 18 ·
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18

High School What does the Minkowski spacetime interval represent and how is it determined?

  • PhanthomJay
  • · Replies 20 ·
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20

High School Very basic questions about visualizing spacetime

  • jaketodd
  • · Replies 7 ·
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7

High School Why does the spaceship rest frame give different elapsed times?

  • Chenkel
  • · Replies 23 ·
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23

Undergrad Schwarzschild spacetime in Kruskal coordinates

  • cianfa72
  • · Replies 43 ·
2
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43

High School Can Motion Exceed the Speed of Light in General Relativity?

  • jaketodd
  • · Replies 20 ·
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20

Undergrad Effects of magnetism on spacetime curvature, and implications

  • jaketodd
  • · Replies 8 ·
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8

Undergrad Equation of state for Einstein field equations

  • grav-universe
  • · Replies 4 ·
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4

Undergrad Principle of relativity and Galileo's group

  • HighPhy
  • · Replies 10 ·
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10

High School How to know what maximal atlas to use for spacetime manifold?

  • Shirish
  • · Replies 12 ·
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12

High School What does symmetry of time dilation really mean?

  • Chenkel
  • · Replies 16 ·
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16

Undergrad Black hole singularity, a time-like surface?

  • Hill
  • · Replies 19 ·
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19

Undergrad Is it only experience that's relative?

  • Elimelech70
  • · Replies 11 ·
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11