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 Gravitational Effects on Aging

  • Benfield
  • · Replies 13 ·
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13

Undergrad Velocity Addition: Angled Motion Explained

  • 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 Inquiry on Matrix Tensor Notation & Meaning 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 Derive 4-Velocity Components: Anyone Know How?

  • 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 Derivation of the Lorentz transformations

  • 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 Explore Clock Synchronisation in a Moving 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 Black Holes & Warp Bubbles - Event Horizon Considerations

  • 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 Spacetime Curve: Mass Effects & 5th Dimension

  • diazdaiz
  • · Replies 4 ·
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4

Undergrad Photon Absorption & Electrons: Mass, Energy & Releasing Photons

  • 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 Accelerator Particles: Speed of Light & Mass Increase

  • Chemong
  • · Replies 18 ·
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18

High School Relativity: Twin Paradox - Is Age Determinable?

  • 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 Universe Expansion: Does Speed of Motion Matter?

  • 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 Solve E=mc2 Condundrum: Views on Logic & Reasoning

  • 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 Is Mach's Principle the Key to Understanding Rotatory Motion?

  • 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 Hawking Radiation Inside a Black Hole: Theory & Possibilities

  • 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 Reimann Tensor Component Form: Charles&Wheeler

  • 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 Black Holes, Gravitational Waves & Gravitons Explained

  • 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 GR Predicts Earth's Orbit Around Sun: Geodesic Path & Curvature

  • 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 Explained: Visualize and Grasp It!

  • 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 Inertial & Gravitational Mass: When Do They 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 Question about an entanglement paper

  • 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 Radius in Schwarzschild Metric: Definition Explained

  • 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 Tensor Field Notation: Einstein Gravity Explained

  • 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 Planck Length: Upper Limit on Photon Frequency & Momentum

  • negativzero
  • · Replies 7 ·
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7

Insights Can I Send a Signal Faster than Light by Pushing a Rigid Rod? - Comments

  • Multiple_Authors
  • · Replies 21 ·
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21

Undergrad Derivation of Geodesics Eq from EM Tensor of Point Particle

  • sergiokapone
  • · Replies 7 ·
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7

Undergrad Issue With Derivation of Gravitational Time Dilation

  • bsalha
  • · Replies 16 ·
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16

Undergrad Gravitational Potential Energy in GR

  • Karl Coryat
  • · Replies 13 ·
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13

High School Prereqs for Posting in Special & General Relativity

  • nearc
  • · Replies 1 ·
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1

Insights Understanding Precession in Special and General Relativity

  • Bill_K
  • · Replies 16 ·
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16

High School Why is time orthogonal to space?

  • jk22
  • · Replies 39 ·
2
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39

Graduate Thermal State in Relativity Theory: Can It Happen?

  • DaTario
  • · Replies 7 ·
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7

Undergrad Accelerated Triangle and Length Contraction

  • Foppe Hoekstra
  • · Replies 40 ·
2
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40

High School Effects on time by gravity or motion

  • Suppaman
  • · Replies 31 ·
2
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31

Graduate Forgetting Non-GR Physics: How Specialists Can Stay Sharp

  • TomServo
  • · Replies 5 ·
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5