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 Questions About Speed of Light & Time

  • uk9999
  • · Replies 35 ·
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Undergrad Why does refraction of light involve a difference in speed?

  • Evans of Sprot
  • · Replies 3 ·
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3

Undergrad Physics Crisis: Faith in Gravity Clarified

  • T@P
  • · Replies 14 ·
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14

Graduate Who does time really slow down for?

  • eNathan
  • · Replies 22 ·
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22

Graduate What are the earliest online publications discussing the Twin Paradox?

  • Prague
  • · Replies 2 ·
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2

High School E =mc{squared} How Did He Arrive At This ?

  • nu_paradigm
  • · Replies 30 ·
2
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30

Graduate Time travel and cosmic strings

  • Hercule Poirot
  • · Replies 3 ·
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3

How Can I Use My Spaceship to Reset My Clock?

  • The Rev
  • · Replies 8 ·
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8

Graduate Discover the AEther Bunny: Understanding Lorentz Relativity and Twin Aging

  • RandallB
  • · Replies 2 ·
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Graduate How Does Time Dilation Affect Colony Ships A and B in Relativity Theory?

  • Dropout
  • · Replies 45 ·
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Graduate Does anybody have a better analogy of describing space-time curvature?

  • Dropout
  • · Replies 9 ·
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9

Graduate How Does Gravity Affect Time Near Earth's Core?

  • RandallB
  • · Replies 2 ·
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2

Graduate Time Dilation and Video Transmission in Relativistic Spaceships

  • Kilroy-was-here
  • · Replies 3 ·
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3

Graduate Relativity situation. Questions.

  • hedons
  • · Replies 2 ·
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2

Graduate Gravity & Photons: Dynamics of a Hypothetical Closed Universe

  • moving finger
  • · Replies 13 ·
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13

Undergrad I know how to travel faster than light :\

  • eNathan
  • · Replies 6 ·
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6

Undergrad Lorentz transformations explanation?

  • guevaramartyr
  • · Replies 11 ·
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11

Graduate Could Time Dilation Explain the Huge Redshifts Observed in Distant Stars?

  • NewImage
  • · Replies 7 ·
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7

Undergrad Energy to Matter: Unlocking E=mc^2

  • oldunion
  • · Replies 10 ·
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10

Graduate Does light bending doubly violate the equivalence principle?

  • wisp
  • · Replies 5 ·
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5

Undergrad An odd sort of symmetry about E=MC^2

  • Dropout
  • · Replies 4 ·
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4

Graduate Conservation Principle Related to Expanding Space?

  • jrdev
  • · Replies 4 ·
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4

Undergrad Why Can One Train Start Up Faster Than the Other After Braking Nose to Nose?

  • Jimmy Snyder
  • · Replies 26 ·
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26

Graduate The Twin Paradox Revisited: A Local Case Study

  • Garth
  • · Replies 44 ·
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44

High School Magnetism & Gravity: Unravelling the Mysteries

  • Someone502
  • · Replies 8 ·
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8

Undergrad The Twins Paradox: A Controversial Truth or a Perplexing Paradox?

  • cire
  • · Replies 129 ·
5
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Undergrad What do you see at light speed?

  • Raptor483
  • · Replies 7 ·
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7

High School Understanding Speed and Time: The Impact of Reaching the Speed of Light

  • bayan
  • · Replies 18 ·
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18

Graduate What Are the Degrees of Freedom for a Massive Spin 1 Particle?

  • joshuaw
  • · Replies 16 ·
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16

Graduate Question about GR - movement in space-time

  • X-43D
  • · Replies 6 ·
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6

Graduate An exercise in eloquence: Basic GTR

  • Crosson
  • · Replies 2 ·
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2

Graduate Is Phase Velocity Greater than c in Spacetime?

  • spacetime
  • · Replies 24 ·
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24

Graduate What's the Flaw in the Relativity Paradox of Gravity and Speed?

  • Shaw
  • · Replies 4 ·
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4

Undergrad Ether Drag Hypothesis Explained - 65 Characters

  • Reshma
  • · Replies 105 ·
4
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105

Undergrad Using four-vectors in derivations and proofs

  • JFo
  • · Replies 6 ·
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6

Undergrad Fleeing earth at the speed of light

  • Pengwuino
  • · Replies 5 ·
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5

Undergrad Race Between Light and Runner: Who Wins?

  • Razor436
  • · Replies 24 ·
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24

Undergrad Twins paradox need clarification

  • Lakshminarayanan.V
  • · Replies 17 ·
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17

Graduate Definition of 4-vector quantities

  • steveurkell
  • · Replies 3 ·
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3

Graduate Reverse engineering relativity?

  • selfAdjoint
  • · Replies 6 ·
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6

Graduate What Are the Effects of Mass and Energy on the Universe's Future?

  • DMuitW
  • · Replies 2 ·
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Time machine possible or impossilble

  • Qyamat
  • · Replies 29 ·
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29

Graduate Tensor gradient and maxwell's equation

  • steveurkell
  • · Replies 2 ·
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2

Undergrad Understanding Matter, Energy & Relativity - How This Can Be?

  • Vereinsamt
  • · Replies 5 ·
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Graduate Invariants in general relativity

  • eljose
  • · Replies 2 ·
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2

Graduate Derivation of Lorentz Transformations

  • Ed Quanta
  • · Replies 12 ·
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12

Graduate Did the Fitzgerald-Lorentz Contraction Explain the Michelson-Morley Experiment?

  • HannonRJ
  • · Replies 7 ·
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7

Graduate Second Postulate of Special Relativity

  • Icebreaker
  • · Replies 7 ·
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7

Graduate Are Both Twins Equivalent in a Torus Universe with the Twin Paradox?

  • touqra
  • · Replies 32 ·
2
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32

Graduate What Does 'Velocity' Mean for a Ray of Light?

  • Symbreak
  • · Replies 5 ·
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5

Einstein Conference: US & Canada Events

  • RandallB
  • · Replies 2 ·
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2

Graduate Question from I. KINEMATICAL PART § 1. Definition of Simultaneity

  • arrell
  • · Replies 19 ·
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Graduate Why is time dilation expressed as t' in special relativity?

  • DB
  • · Replies 9 ·
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9

High School E=MC^2 - Do I have this right?

  • ShadowKnight
  • · Replies 8 ·
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8

Undergrad Is there a thread or website to learn the theory of relativity from A-Z?

  • guevara0001
  • · Replies 11 ·
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11

Graduate Explaining a Paradox in Modern Physics

  • genxhis
  • · Replies 22 ·
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22

Graduate Black Holes in the Very Early Universe

  • DrChinese
  • · Replies 9 ·
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9

Graduate A little problem in general relativity;momentum

  • haushofer
  • · Replies 13 ·
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13

Graduate What is the Limits of Lorentz Transformation when (v/c->1)?.

  • controlfreak
  • · Replies 8 ·
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8

Graduate GR: Black Hole - Electrical Charge

  • RandallB
  • · Replies 2 ·
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2

Graduate What explains the increase in mass at high speeds?

  • Symbreak
  • · Replies 10 ·
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10

Graduate Harmless Lorentz transformation question

  • Physicsguru
  • · Replies 101 ·
4
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101

Graduate Is only GR enough for proved the event horizon

  • hypernova
  • · Replies 4 ·
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4

Graduate How Do Lorentz Transformations Work with Y and Z Components of Speed?

  • quasar987
  • · Replies 29 ·
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29

Graduate Relativistic Mass of an Orbiting Billiard Ball

  • Physicsguru
  • · Replies 44 ·
2
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44

Undergrad Relativistic Mass: Fact or Fiction?

  • misogynisticfeminist
  • · Replies 16 ·
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16

Graduate Derivation of the momentum-energy relation

  • misogynisticfeminist
  • · Replies 10 ·
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10

Graduate Is the General Theory of Relativity Worth Learning from a Troll?

  • ClarkKent
  • · Replies 7 ·
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7

Graduate New to Relativity:Need Answers

  • Raptor483
  • · Replies 4 ·
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4

Graduate Relativity and temperature question

  • Physicsguru
  • · Replies 52 ·
2
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52

Einstein's Mass-Energy Equivalence

  • quasar987
  • · Replies 7 ·
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7

Graduate Unification of GR and classical E&M

  • metrictensor
  • · Replies 26 ·
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26

Graduate Why Does Light Have No Rest Mass While Other Particles Do?

  • munky99999
  • · Replies 10 ·
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10

Graduate Weighing Mass of Photons in Different Directions

  • gonzo
  • · Replies 16 ·
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16

Graduate Is matter truly keeping pace with the expansion of space?

  • wolram
  • · Replies 26 ·
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26

Graduate Help with a little Gedanken experiment please?

  • cepheid
  • · Replies 5 ·
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5

Undergrad Plank & Bullet Experiment: Questions Explained

  • Infamo
  • · Replies 2 ·
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2

Undergrad Galilean Transformation Question

  • misogynisticfeminist
  • · Replies 4 ·
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4

Graduate Time Reversed: Can Humans Think?

  • eNathan
  • · Replies 6 ·
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6

Graduate RF SR: What If I'm Anchored to a Moving Train?

  • misogynisticfeminist
  • · Replies 2 ·
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2

Undergrad Derivation of relativistic energy

  • misogynisticfeminist
  • · Replies 2 ·
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2

Graduate Is time dialation really *time* dialation?

  • CarpetFilter
  • · Replies 5 ·
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5

Graduate Hamilton-Jacobi equation for Gr

  • eljose
  • · Replies 2 ·
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2

Graduate Relativistic effects in non-vacuous media

  • freemind
  • · Replies 3 ·
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3

Graduate Possible solution for dark energy

  • wolram
  • · Replies 14 ·
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14

Graduate Question About Relativistic Acceleration

  • Physicsguru
  • · Replies 84 ·
3
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84

Undergrad What Experiments Provide Evidence for General Relativity?

  • djmike
  • · Replies 8 ·
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8

Undergrad Unraveling the Gamma Factor Equation

  • Infamo
  • · Replies 4 ·
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4

Undergrad Why does E=MC^2 require the speed of light and why is it squared?

  • KingNothing
  • · Replies 5 ·
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5

Graduate How to retrieve the lenght-contraction from the LT?

  • quasar987
  • · Replies 6 ·
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6

Graduate What is the accuracy of world time and can it be improved?

  • wisp
  • · Replies 3 ·
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3

Graduate Einstein's Quadrapole Model for Gravity Waves

  • yogi
  • · Replies 23 ·
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23

Graduate Time Travel: Examining the Possibilities

  • CeeAnne
  • · Replies 19 ·
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19

Graduate Quick question for a confused English major

  • Eldian
  • · Replies 4 ·
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4

Graduate Is gravitation faster than light?

  • CarstenDierks
  • · Replies 90 ·
4
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90

Graduate Stationary Einstein-Vlasov system

  • JohanL
  • · Replies 3 ·
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3

Has anyone heard any more about this guy

  • Cosmo16
  • · Replies 5 ·
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5

Graduate What is the Mass Density of a Magnetic Field in Relativity?

  • pmb_phy
  • · Replies 2 ·
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2

High School The Sun revolves around the Earth?

  • eNathan
  • · Replies 12 ·
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12

Graduate How Does Sectional Curvature Define Spacetimes in General Relativity?

  • hellfire
  • · Replies 2 ·
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2