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 Physical meaning of a spacelike geodesic

  • accdd
  • · Replies 62 ·
3
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62

Graduate Can a conformal flat metric be curved?

  • Kurvature
  • · Replies 5 ·
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5

Undergrad Radiate Single Charged Particle: Free Fall in Black Hole?

  • accdd
  • · Replies 1 ·
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1

Undergrad Distance Contraction: Is D or D*sqrt(1-(v/c)^2) Traveled?

  • Kairos
  • · Replies 27 ·
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27

Insights Rindler Motion in Special Relativity: Hyperbolic Trajectories - Comments

  • stevendaryl
  • · Replies 29 ·
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29

Graduate Generalize Special Relativity for Flat Spacetime

  • Ans
  • · Replies 8 ·
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8

Undergrad Gravitoelectromagnetism: Why Equation Differs in Sources

  • olgerm
  • · Replies 1 ·
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1

Graduate Affine Spaces and Vector Spaces

  • vanhees71
  • · Replies 82 ·
3
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82

High School Gravitational Time Dilation on Mountaintops: New Member Questions

  • jeepdriver74
  • · Replies 11 ·
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11

High School Length, Time, and Velocity -- Which are fundamental quantities?

  • Keith Koenig
  • · Replies 50 ·
2
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50

Undergrad Effects of Supermassive Black Hole Merger on Nearby Bodies

  • Hornbein
  • · Replies 2 ·
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2

Undergrad Is Acceleration an Invariant? (Taylor & Wheeler)

  • Freixas
  • · Replies 7 ·
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7

Undergrad Cat Chasing Red Dot Faster Than c: Results & Analysis

  • Halc
  • · Replies 13 ·
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13

Undergrad Difference between proper time and coordinate time

  • Silviu
  • · Replies 36 ·
2
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36

Undergrad Length contraction in General Relativity

  • knowwhatyoudontknow
  • · Replies 64 ·
3
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64

Graduate Wald's Abstract Index Notation: Explaining T^{acde}_b

  • madsmh
  • · Replies 4 ·
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4

High School Why are gravitons needed to explain gravitational attraction?

  • lukegregor
  • · Replies 8 ·
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8

Undergrad Spacetime Curvature via Triangle

  • Narasoma
  • · Replies 2 ·
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2

Undergrad Defining the components of a metric

  • Pencilvester
  • · Replies 24 ·
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24

High School Simple reasoning that the equivalence principle suggests curvature

  • luinthoron
  • · Replies 48 ·
2
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48

High School Build a Time Dilation Clock for 8th Grade Science Project

  • Dc2LightTech
  • · Replies 25 ·
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25

Undergrad Wilbert Zweistein's Objection to Equivalence Principle

  • ergospherical
  • · Replies 13 ·
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13

Undergrad Index Gymnastics: Tensor Product of 4-Vectors & Tensors

  • Milsomonk
  • · Replies 3 ·
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3

Undergrad Can a Basis Vector be Lightlike?

  • cianfa72
  • · Replies 28 ·
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28

Undergrad Can time run backwards in an accelerating frame?

  • Gumby The Green
  • · Replies 125 ·
5
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125

High School Ride Gravitational Waves to Increase Speed?

  • wcivch
  • · Replies 6 ·
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6

Graduate Proving $g(u,v)≠0$ with Linear Independence

  • isaacdl
  • · Replies 11 ·
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11

High School Does this thought experiment show that Space must be curved?

  • peterraymond
  • · Replies 17 ·
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17

Undergrad Differences b/w Schwarzschild Radius & Event Horizon

  • accdd
  • · Replies 11 ·
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11

Undergrad Schwarzschild Metric & Particle Absorption

  • accdd
  • · Replies 8 ·
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8

Undergrad Rindler Wedge: Timelike or Spacelike? Intuition & Light Cone

  • knowwhatyoudontknow
  • · Replies 4 ·
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4

Undergrad Energy conditions and non-physical phenomena

  • accdd
  • · Replies 5 ·
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5

High School Black Hole Event Horizon: Atom Effects & Wave Detection

  • accdd
  • · Replies 20 ·
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20

High School Why is the BH Information Paradox Called a Paradox?

  • Grinkle
  • · Replies 8 ·
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8

Graduate Relation of Electromagnetic Field & Field Tensor

  • carpinus
  • · Replies 18 ·
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18

High School How Can We Observe Black Holes Growing?

  • mef
  • · Replies 96 ·
4
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96

Undergrad Is a Flat, Expanding Universe Compatible with GR and Newtonian Mechanics?

  • Pony
  • · Replies 7 ·
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7

High School Rotation of Galaxies: Mass vs Dark Matter?

  • accdd
  • · Replies 7 ·
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7

High School Gravity-like Force: Is Another Force Weaker Than Gravity?

  • accdd
  • · Replies 3 ·
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3

Graduate Comparing Gullstrand-Painleve & Lemaitre Coordinates

  • PAllen
  • · Replies 8 ·
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8

Undergrad GR: Practical Problem Sets w/ Solutions

  • zwoodrow
  • · Replies 2 ·
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2

Undergrad Is there really nothing faster than light?

  • SvenDahlhaus
  • · Replies 40 ·
2
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40

High School Energy Conservation w/ Charged Battery Time Travel

  • Lars Krogh-Stea
  • · Replies 3 ·
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3

Undergrad Black Hole: Knock on the horizon

  • mef
  • · Replies 34 ·
2
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34

Undergrad What is the Meaning of Lagrangian in Special Relativity?

  • jbergman
  • · Replies 7 ·
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7

Graduate Anti-self Dual Part (2,2) Riemann Curvature Tensor

  • abhinavabhatt
  • · Replies 2 ·
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2

High School Gravitational Lensing: Magnification of Galaxies

  • Mikael17
  • · Replies 5 ·
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5

Undergrad Applying Reisenbach Transf. to EM Wave in Microwave Oven

  • wnvl2
  • · Replies 16 ·
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16

Undergrad How to Measure Speed of Light & Is It Constant?

  • mef
  • · Replies 13 ·
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13

Undergrad Gravitomagnetic Experiment: Possibility & Calculations

  • olgerm
  • · Replies 8 ·
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8

Undergrad Time Travel in Newtonian Spacetime: Is it Possible?

  • accdd
  • · Replies 2 ·
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2

Undergrad Comparing Clock Rates in Accelerated vs Constant Velocity Frames

  • Freixas
  • · Replies 14 ·
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14

High School Can Accelerate at Constant g in Own FoR?

  • S Holtom
  • · Replies 33 ·
2
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33

Undergrad Ideal Fluids & General Relativity: Why Needed?

  • accdd
  • · Replies 15 ·
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15

High School Galilean vs Lorentz Transformations: Correct Understanding?

  • David Lewis
  • · Replies 10 ·
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10

Undergrad How Does Time Dilation Affect the Twin Paradox in Special Relativity?

  • sennetor
  • · Replies 9 ·
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9

Undergrad Constant Velocity Motion in Relativity: Radiation Effects?

  • accdd
  • · Replies 23 ·
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23

Undergrad Isotropy of the speed of light

  • andrew s 1905
  • · Replies 264 ·
9
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264

Undergrad General Relativity: Is it Local?

  • accdd
  • · Replies 2 ·
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2

Undergrad Deriving Special Relativity from Particle Indistinguishability

  • accdd
  • · Replies 3 ·
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3

Undergrad Gravitational vs. Electromagnetic Waves: What's the Difference?

  • accdd
  • · Replies 20 ·
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20

High School Creating Artificial Black Hole: Force Requirements

  • Devin-M
  • · Replies 11 ·
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11

High School Robert Wald's General Relativity: Energy-Momentum Relation

  • carpinus
  • · Replies 8 ·
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8

Undergrad Proof of Special Relativity w/ Michelson–Morley Experiment

  • FMJalink
  • · Replies 20 ·
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20

Graduate Alcubierre Metric: York Time Cause and Effect

  • MattRob
  • · Replies 3 ·
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3

Undergrad Light speed independent of source

  • Martyn Arthur
  • · Replies 22 ·
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22

Undergrad Understand Poynting Density of Flow of Energy w/Weak Physics Background

  • Mike Karr
  • · Replies 9 ·
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9

High School Frequency of Gravitational Waves: Limit & Possibilities

  • DaveC426913
  • · Replies 15 ·
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15

Graduate Does Spacetime Absorb Energy in General Relativity?

  • Suekdccia
  • · Replies 17 ·
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17

Graduate MTW Gravitation: Exercise 5.1 | Beginner GR Stress-Energy Tensor Symmetry

  • Mike Karr
  • · Replies 15 ·
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15

Undergrad Relative Motion vs. 'Relative' Acceleration: Twin 1 & 2

  • Martyn Arthur
  • · Replies 16 ·
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16

Undergrad Reichenbach Synchronisation: Proving i=r

  • wnvl2
  • · Replies 3 ·
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3

Undergrad A paradox for two moving protons?

  • FranzDiCoccio
  • · Replies 30 ·
2
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30

Graduate Local phase invariance of complex scalar field in curved spacetime

  • Tertius
  • · Replies 2 ·
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2

High School General Relativity: Action & Reaction in Gravitation

  • Giuly
  • · Replies 15 ·
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15

Undergrad About global inertial frames in GR

  • cianfa72
  • · Replies 78 ·
3
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78

High School Creating a Wormhole: Process & Theory

  • Andre_86
  • · Replies 3 ·
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3

High School Can Push Travel Faster Than Light?

  • PCNerdz
  • · Replies 5 ·
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5

Undergrad Gravity on the Moon vs. on the spinning Earth

  • jon2
  • · Replies 10 ·
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10

High School Gravity vs Acceleration: The Impact on Clocks in Reference Frame R

  • calinvass
  • · Replies 58 ·
2
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58

Undergrad Why does a body at rest move if Gravity is not a force?

  • zoltrix
  • · Replies 70 ·
3
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70

High School Gravitational Force acting on a massless body

  • Lunct
  • · Replies 67 ·
3
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67

Undergrad Relativity paradox: rocket landing in a cylinder

  • wnvl2
  • · Replies 50 ·
2
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50

Undergrad Deriving Lorentz Transformations: Hyperbolic Functions

  • Samama Fahim
  • · Replies 33 ·
2
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33

Undergrad Discussing General Relativity - Beliefs & Ideas

  • Jamestein Newton
  • · Replies 1 ·
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1

High School A difficulty with the equivalence of all inertial reference frames

  • JuanGC
  • · Replies 28 ·
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28

High School Black Hole Entropy: Basis of Logarithm Explored

  • gerald V
  • · Replies 11 ·
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11

Graduate Energy-Momentum Tensor for 2-Body Problem: Approach

  • captainbleak
  • · Replies 2 ·
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2

High School Can You Become a Black Hole from Approaching Light Speed?

  • bbbl67
  • · Replies 25 ·
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25

Undergrad Understanding Lorentz Factor & Proper Time Invariance

  • e2m2a
  • · Replies 32 ·
2
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32

Graduate What is the Expression for the Waveform of an In-Spiralling Compact Binary?

  • ergospherical
  • · Replies 1 ·
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1

Undergrad Computing Volume in General Relativity: Use of Tensor & Friedmann Eqns

  • Tertius
  • · Replies 8 ·
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8

Undergrad Understanding Gravity with GR: Beginner's Guide by Aerodyn

  • Aerodyn
  • · Replies 10 ·
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10

Undergrad Does Lorentz invariance imply Einstein's synchronization convention?

  • cianfa72
  • · Replies 32 ·
2
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32

Insights Understanding the General Relativity view of gravity on Earth - Comments

  • Dale
  • · Replies 135 ·
5
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135

Graduate Special Relativity: A^μ_ν Differences Explained

  • LagrangeEuler
  • · Replies 6 ·
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6

Undergrad Can Gravity Escape a Black Hole?

  • Vandenburg
  • · Replies 21 ·
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21

Undergrad Proper Time & 4-vectors: Clarification Needed

  • e2m2a
  • · Replies 20 ·
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20

Undergrad Is a Manifold with a Boundary Considered a True Manifold?

  • Dale
  • · Replies 202 ·
7
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202

Undergrad Curved space and gravitational waves

  • Nidhi1007
  • · Replies 6 ·
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6