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

Graduate Derivation of Einstein Field Equations w/o Poisson or Least Action

  • EagleH
  • · Replies 4 ·
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4

Graduate How to calculate the Riemann curvature at r=2GM?

  • Bishal Banjara
  • · Replies 62 ·
3
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62

High School Does a Black Hole with Lower Density Than Water Float or Sink?

  • fluidistic
  • · Replies 20 ·
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20

High School Second Postulate of Special Relativity Explained

  • Wolfgang Stracke
  • · Replies 21 ·
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21

High School MinutePhysics Special Relativity Series

  • ZapperZ
  • · Replies 43 ·
2
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43

High School New Paradox: Gamma Light & Relativistic Doppler Effect

  • Alfredo Tifi
  • · Replies 4 ·
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4

Undergrad Traveling at Light Speed: Is a Photon Stationary?

  • Joe
  • · Replies 6 ·
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6

Undergrad Simultaneity and the Twin Paradox

  • Freixas
  • · Replies 138 ·
5
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138

Graduate Reporting my own post to bring this to the attention of a moderator.

  • e-pie
  • · Replies 39 ·
2
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39

Graduate Explore Potential Energy, Pressure & Newtonian Gravity

  • Jonathan Scott
  • · Replies 16 ·
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16

High School Is Lorentz Contraction Bona Fide or Just A "Perspective"?

  • Wolfgang Stracke
  • · Replies 13 ·
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13

High School Simulation of a neutron star's impact on a supermassive black hole?

  • The Bill
  • · Replies 24 ·
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24

High School What are the implications of a 24-light-hour tower at the Earth's equator?

  • My_name_is_Peter
  • · Replies 4 ·
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4

Undergrad Alcubierre Metric: Explaining Dark Matter Halo Speed

  • Jetro
  • · Replies 8 ·
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8

Undergrad EoM via varying action - covariant derivative when integrate

  • binbagsss
  • · Replies 12 ·
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12

Undergrad Relative Simultaneity: Flashlight in Moving Ship

  • Kiley
  • · Replies 39 ·
2
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39

Graduate Topology of Black Holes: Decomposing the Manifold and the Role of Knots

  • nateHI
  • · Replies 12 ·
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12

Graduate Problem with a basic theorem in Wald's GR book

  • facenian
  • · Replies 8 ·
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8

High School Is There a Formula for Gm/r in Gravitational Potential?

  • concernedhuman
  • · Replies 2 ·
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2

High School Ideas for Teaching Relativity to High School Kids

  • Luis Babboni
  • · Replies 13 ·
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13

Undergrad Metric Compatibility: Is It Forbidden?

  • kent davidge
  • · Replies 12 ·
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12

Undergrad Can Gravitational Waves Explain Uniform Space Expansion in the Universe?

  • l0st
  • · Replies 16 ·
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16

Undergrad Satellite Orbit synchronization

  • name123
  • · Replies 126 ·
5
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126

Undergrad Is E=mc^2 Explained Correctly?

  • Brian1952
  • · Replies 3 ·
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3

Undergrad Effect of Relativity on Laser Sail Acceleration

  • Sebastiaan
  • · Replies 15 ·
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15

High School Mass-Energy Equivalence: Matter as Potential Energy?

  • Aidyan
  • · Replies 16 ·
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16

Graduate Calculating Christoffel Symbol with Rotating Metric

  • MathematicalPhysicist
  • · Replies 25 ·
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25

Undergrad What is the Term for ds in Spacetime Interval Equation?

  • nomadreid
  • · Replies 16 ·
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16

Undergrad Lorentz Group: Tensor Representation Explained

  • chingel
  • · Replies 4 ·
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4

High School Observational Effects of "FTL" spotlight from laser pointer?

  • AndromedaRXJ
  • · Replies 50 ·
2
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50

Undergrad Relativistic formula for motion with constant acceleration

  • bobie
  • · Replies 55 ·
2
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55

Undergrad What I understand about Time Dilation

  • name123
  • · Replies 83 ·
3
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83

Graduate Given a Metric, find the constants of motion

  • MathematicalPhysicist
  • · Replies 12 ·
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12

High School Understanding Minkowski: Einstein, Relativity & Absolute Simultaneity

  • Joao
  • · Replies 10 ·
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10

Undergrad Force on Moving Charge: Lorentz Transformation & Point Charge

  • QuasarBoy543298
  • · Replies 2 ·
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2

Undergrad Deriving Maxwell's Equations from Field Tensor (Griffith 4ed)

  • omega_minus
  • · Replies 6 ·
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6

Undergrad Can Wormholes Be Created Without Exotic Particles?

  • Umaxo
  • · Replies 1 ·
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1

Undergrad Reconciling two observers in two frames

  • Freixas
  • · Replies 56 ·
2
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56

Undergrad Covariant Derivative Equivalence: Exploring an Intriguing Result

  • kent davidge
  • · Replies 4 ·
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4

Undergrad Extreme Length Contraction: Classical to Quantum?

  • Silviu
  • · Replies 16 ·
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16

High School Why is the speed of light a constant?

  • Sjm_dynamo
  • · Replies 18 ·
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18

Graduate Rods, Clocks & Free Fall: Metric & Connections in GR

  • shahbaznihal
  • · Replies 11 ·
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11

Graduate What are the possible radii for free falling motion in a rocket trip?

  • MathematicalPhysicist
  • · Replies 2 ·
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2

High School Speed of Light Slowed for SuperBig Observer?

  • Romanko
  • · Replies 9 ·
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9

Undergrad Gravity & Time: Is it Possible?

  • jim77
  • · Replies 5 ·
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5

Graduate The Metric Matrix: How Can I Invert a Non-Diagonal Matrix?

  • MathematicalPhysicist
  • · Replies 12 ·
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12

High School Motion vs Time: Does Time Affect Motion?

  • Fernando Freire
  • · Replies 10 ·
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10

High School Universe's Flatness: Mass, Gravity, Dark Energy Explained

  • robbierobb
  • · Replies 9 ·
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9

Graduate On metric and connection independence

  • shahbaznihal
  • · Replies 15 ·
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15

Undergrad Can We Choose a Coordinate System for a Levi-Civita Connection on Manifolds?

  • kent davidge
  • · Replies 34 ·
2
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34

High School How can any physical body truly be at rest?

  • platosuniverse
  • · Replies 24 ·
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24

Graduate Discuss Open Problems in Gravity & Cosmology | Join the Conversation

  • shahbaznihal
  • · Replies 1 ·
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1

Undergrad Solving Tensor Calculus Question from Schutz Intro to GR

  • shahbaznihal
  • · Replies 7 ·
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7

Undergrad Will a spring extend more when going at relativistic speeds?

  • Idunno
  • · Replies 55 ·
2
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55

High School Fresnel's Formula & Ether Drag: Resnick Book Confusion

  • Arup Biswas
  • · Replies 1 ·
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1

High School Can Anything Go Through a Black Hole?

  • Gonzalo
  • · Replies 12 ·
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12

Undergrad Comparing tensors at different points

  • Pencilvester
  • · Replies 2 ·
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2

Undergrad Does infinite one-way speed of light violate p conservation?

  • Sorcerer
  • · Replies 28 ·
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28

Undergrad Measuring 1-Way Speed of Light: 15m Fibers & 1GHz Pulse Generator

  • CompSci
  • · Replies 15 ·
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15

High School Why Albert Einstein's Original Concept for a Black Hole?

  • K. Doc Holiday
  • · Replies 18 ·
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18

Undergrad Can Black Holes Transport Mass Back in Time?

  • FyrenEyce
  • · Replies 11 ·
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11

Undergrad Nearly Lorentz Coordinate System Explained

  • Silviu
  • · Replies 11 ·
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11

High School Understanding the Meaning of "Proper Time"

  • Zephaniah
  • · Replies 36 ·
2
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36

Undergrad Tensors: Bar Symbol Over Functions or Indices?

  • kent davidge
  • · Replies 5 ·
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5

High School Does the size of the Universe change with motion?

  • platosuniverse
  • · Replies 13 ·
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13

Undergrad Principle of Equivalence: Are You in a Gravitational Field?

  • Sandeep T S
  • · Replies 7 ·
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7

Undergrad EFE: Deriving Speed of Gravity, Gravitational Waves?

  • SamRoss
  • · Replies 4 ·
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4

Undergrad Difference Between T_{a}^{b} & T^{a}_{b}: (1,1) Tensors

  • quickAndLucky
  • · Replies 3 ·
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3

High School Dark Matter & Quantum Gravity: Is Unknown Property at Play?

  • joelr
  • · Replies 8 ·
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8

Undergrad Circle tangential velocity approaching c

  • Osvaldo
  • · Replies 27 ·
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27

High School Express Velocity in Formula: Find Answer

  • hugo_faurand
  • · Replies 15 ·
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15

High School Electric Field in Accelerating Elevator

  • jartsa
  • · Replies 15 ·
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15

Undergrad Alcubierre Warp Drive: 2nd Law of Thermodynamics Impossibility?

  • Randy Subers
  • · Replies 3 ·
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3

High School Einstein's Theories: Fact or Fiction? Research Q&A

  • Charles Shahar
  • · Replies 4 ·
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4

Undergrad Why special relativity is unsuitable to describe gravity

  • Adel Makram
  • · Replies 63 ·
3
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63

Undergrad Levi-Civita Contraction Meaning: Undergrad Research

  • cmcraes
  • · Replies 1 ·
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1

High School Beginner Question: Causality & Relativity in Quantum Mechanics

  • Joao
  • · Replies 9 ·
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9

Undergrad 2as = v^2 an other equations dealing with the past

  • spino
  • · Replies 3 ·
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3

Undergrad Still have questions about photon mass

  • SamRoss
  • · Replies 22 ·
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22

Undergrad Maxwell's Equations & GR: How Scientists Got Away With It

  • Sorcerer
  • · Replies 4 ·
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4

Undergrad Local meaning of the equivalence principle

  • craigthone
  • · Replies 29 ·
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29

High School Einstein's Thought Experiment on Simultaneity | Newbie Q&A

  • paulie2018
  • · Replies 14 ·
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14

High School Could frame dragging explain dark matter on a large scale?

  • RonH
  • · Replies 3 ·
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3

Undergrad Compton Scattering w/Moving Electron: Turner's Eq 5.29

  • Ken Miller
  • · Replies 2 ·
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2

Undergrad Geodesic Deviation: Definition of Connecting Vector

  • Silviu
  • · Replies 6 ·
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6

Undergrad Can an object be both a black hole and not a black hole?

  • friend
  • · Replies 3 ·
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3

High School Relativistic Energy: Change of Consts. of Integration

  • SamRoss
  • · Replies 3 ·
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3

Undergrad Paradox: Electron Radiates in a Gravitational Field

  • Gene Naden
  • · Replies 114 ·
4
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114

Undergrad Non-coordinate Basis: Explained

  • Silviu
  • · Replies 7 ·
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7

High School Comparing Ages: Spaceship Rider vs Earthbound

  • Zephaniah
  • · Replies 9 ·
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9

Undergrad Understanding Time Dilation and Differential Aging in the Twin Paradox

  • t_ras
  • · Replies 12 ·
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12

Undergrad Can a Magnetic Field Create Gravity?

  • essenmein
  • · Replies 6 ·
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6

Insights The Speed of Light and of Galilean Relativity - Comments

  • klotza
  • · Replies 37 ·
2
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37

Graduate Calc Magnitude of Proper Accel w/ 3-Vectors & 4-Vectors

  • pervect
  • · Replies 11 ·
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11

High School Maxwell's EM Theory vs Principle of Relativity

  • HAF
  • · Replies 6 ·
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6

Undergrad Equivalence Principle: Controversy & Misinterpretations

  • facenian
  • · Replies 12 ·
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12

Undergrad Reconciling Spacetime & Quantum Uncertainty

  • bahamagreen
  • · Replies 22 ·
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22

Undergrad Commutator of two vector fields

  • Pencilvester
  • · Replies 8 ·
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8

Undergrad Calculating different time frames

  • Dhruv007
  • · Replies 33 ·
2
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33

Undergrad Black Holes: Draining Empty Spacetime?

  • Islam Hassan
  • · Replies 18 ·
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18