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 Rindler coordinates and proper acceleration of observers

  • cianfa72
  • · Replies 16 ·
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16

Undergrad The Universe filled with a "homogeneous perfect fluid"

  • MathematicalPhysicist
  • · Replies 30 ·
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30

High School Do black holes determine time's arrow?

  • shlosmem
  • · Replies 124 ·
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124

Undergrad A problem with the solution to the ladder paradox

  • student34
  • · Replies 15 ·
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15

High School Basic introduction to gravitation as curved spacetime

  • cianfa72
  • · Replies 57 ·
2
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57

Undergrad Is the sign of the Einstein equation right in Chandrasekhar's Black holes?

  • timeant
  • · Replies 13 ·
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13

High School Can we see matter crossing the Event Horizon with a powerful telescope?

  • wsullivan
  • · Replies 21 ·
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21

Undergrad Assumption in the derivation of the Lorentz transformation

  • Kyouran
  • · Replies 33 ·
2
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33

High School Do gravitons relate to spacetime curvature and can they escape black holes?

  • Kairos
  • · Replies 4 ·
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4

High School Is length contraction (Lorentz transformation) an illusion or real?

  • student34
  • · Replies 24 ·
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24

Undergrad Understanding Jacobian Matrix Transformation in Special Relativity

  • Harry Case
  • · Replies 8 ·
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8

Undergrad Defining the Rindler horizon for observers in all spacetimes

  • PAllen
  • · Replies 10 ·
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10

Undergrad Absolute meaning of spatial deviaton angle of light around the sun

  • wnvl2
  • · Replies 2 ·
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2

Graduate Rindler horizons for radial Rindler trajectories in Schwarzschild spacetime

  • ergospherical
  • · Replies 21 ·
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21

Undergrad Bondi ##k##-factor concept from first principles

  • Shirish
  • · Replies 41 ·
2
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41

High School Equivalence Principle and Rindler Horizons

  • sbaker8688
  • · Replies 36 ·
2
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36

Insights Geodesic Congruences in FRW, Schwarzschild and Kerr Spacetimes

  • ergospherical
  • · Replies 8 ·
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8

High School Free fall floating in a closed spaceship near a gravity source

  • roineust
  • · Replies 4 ·
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4

High School Distance Length Contraction at Light Speed

  • MikeeMiracle
  • · Replies 1 ·
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1

Undergrad Observer Inside Collapsing Shell

  • Tomas Vencl
  • · Replies 6 ·
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6

Undergrad Reference Frame, Difference in Kinetic Energy, Fuel Consumed

  • MattGeo
  • · Replies 19 ·
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19

High School Why does it require an infinite amount of energy to reach the speed of light?

  • mucker
  • · Replies 130 ·
5
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130

High School Is there an inside to a Black Hole?

  • stevil
  • · Replies 63 ·
3
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63

Undergrad Is acceleration absolute or relative - follow up

  • cianfa72
  • · Replies 38 ·
2
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38

Undergrad Reference frame vs coordinate chart

  • cianfa72
  • · Replies 61 ·
3
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61

Undergrad Pitfalls in reading spacetime diagrams with Bob and Alice

  • Freixas
  • · Replies 33 ·
2
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33

Undergrad 2D Minkowski spacetime diagram generator specification review

  • Freixas
  • · Replies 6 ·
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6

Graduate Deriving radial excess from the Ricci tensor component

  • Thytanium
  • · Replies 16 ·
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16

Undergrad Why does a clock tick slower at constant speed on a 3D torus?

  • appot89
  • · Replies 3 ·
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3

Undergrad Can null paths detect geodesic deviation in gravitational wave interferometers?

  • cianfa72
  • · Replies 11 ·
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11

Insights Relativity using the Bondi k-Calculus - Comments

  • robphy
  • · Replies 21 ·
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21

Undergrad Gravitational Field of Electromagnetic Waves: How is it Generated?

  • MartinG
  • · Replies 8 ·
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8

Insights Relativity variables: velocity, Doppler-Bondi k, and rapidity

  • robphy
  • · Replies 13 ·
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13

Undergrad A computation of an integral on page 344 of Schutz's textbook

  • MathematicalPhysicist
  • · Replies 4 ·
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4

Undergrad Hafele-Keating experiment: what balances SR effects in the plane frame?

  • name123
  • · Replies 54 ·
2
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54

High School How does curvature of spacetime affect the motion of test particles?

  • sqljunkey
  • · Replies 3 ·
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3

Undergrad Does information survive in gravitational waves from merging black holes?

  • arusse02
  • · Replies 12 ·
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12

Undergrad Angle-Preserving Linear Transformations in 2D Space for Relativity

  • Shirish
  • · Replies 2 ·
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2

Graduate Frame fields in Rovelli's approach to general relativity

  • joneall
  • · Replies 7 ·
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7

Undergrad How do time dilation effects combine for a fast-moving ship near massive objects?

  • ronald_hinh
  • · Replies 8 ·
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8

Graduate Orbiting spaceship just above a black hole horizon

  • AndreiB
  • · Replies 2 ·
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2

Undergrad Conservation of momentum in a collision

  • Grasshopper
  • · Replies 67 ·
3
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67

Undergrad Kinetic vs Gravitational Time Dilation: Perceived Speed

  • Involute
  • · Replies 5 ·
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5

High School L = 0 in the equation for effective potential energy?

  • sqljunkey
  • · Replies 3 ·
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3

High School Why does the falling observer's proper time seem more real than the ship observer's?

  • Grinkle
  • · Replies 6 ·
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6

Undergrad Solving Spinorial Maxwell's Equations with Wald

  • ergospherical
  • · Replies 1 ·
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1

Undergrad Synchronous coordinates and hypersurface orthogonality

  • cianfa72
  • · Replies 16 ·
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16

Undergrad Black hole formation watched from a distance

  • haushofer
  • · Replies 37 ·
2
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37

Undergrad Proving Lorentz Metric on Real Type (1,0;1,0) Tensors in Wald Ch. 13

  • ergospherical
  • · Replies 2 ·
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2

Undergrad Cartan's Understanding of Einstein Field Equation

  • dx
  • · Replies 1 ·
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1

Undergrad Kerr Black Hole: Superradiance Flux - Show Negative when 0<ω<mΩH

  • ergospherical
  • · Replies 2 ·
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2

Undergrad Can energy be a vector in E=mc2 if it's a product of scalars?

  • andrecoelho
  • · Replies 12 ·
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12

Undergrad Inverting the relativistic force equation for acceleration

  • lriuui0x0
  • · Replies 20 ·
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20

High School Time Dilation in a Galaxy: Calculating Mass Effects

  • sha1000
  • · Replies 7 ·
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7

Undergrad Does Time Drive Black Hole Travelers to a Central Singularity?

  • .Scott
  • · Replies 13 ·
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13

Undergrad How Long Does it Take to Fall into a Black Hole?

  • Jackzim
  • · Replies 43 ·
2
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43

Undergrad GW detectors -- How much has their sensitivity improved since 2008?

  • MathematicalPhysicist
  • · Replies 1 ·
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1

High School Understanding Spacetime Diagrams from "Reality is not What it Seems

  • fee_de
  • · Replies 6 ·
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6

Undergrad Principle of relativity for proper accelerating frame of reference

  • cianfa72
  • · Replies 144 ·
5
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144

Undergrad Shape of de Sitter Universe: Is Hyperboloid Misleading?

  • gerald V
  • · Replies 2 ·
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2

Undergrad Time travel is a fact or fiction.?

  • Zeeshan Ahmad
  • · Replies 9 ·
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9

High School Does a charged particle on Earth's surface emit radiation?

  • Amaterasu21
  • · Replies 13 ·
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13

Undergrad Does time dilation occur due to the speed limit of light or c?

  • mucker
  • · Replies 47 ·
2
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47

Undergrad Understanding Frequency in Rindler Coordinates for a Scalar Massless Field

  • Haorong Wu
  • · Replies 2 ·
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2

High School Does the twin in curved spacetime age differently following geodesics around a planet?

  • D.S.Beyer
  • · Replies 25 ·
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25

Undergrad Future null infinity confusion

  • Dale
  • · Replies 30 ·
2
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30

Undergrad Distinguishing Einstein Cartan from GR: Experiments

  • Dale
  • · Replies 5 ·
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5

High School Time Dilation: Traveling to a Distant Star in 4.5yr

  • versine
  • · Replies 4 ·
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4

Undergrad Deriving the factor ρ^−2g(ζ) in 't Hooft's Rindler transformation

  • wnvl2
  • · Replies 1 ·
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1

High School Can objects appear to accelerate as spacetime expands?

  • Martin Philpott
  • · Replies 11 ·
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11

High School What physical mechanism causes matter to bend space and slow time?

  • TheTuringTester
  • · Replies 11 ·
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11

Undergrad Natural direction of pushforwards and pullbacks

  • ergospherical
  • · Replies 4 ·
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4

Graduate Condition for a spacelike surface to be achronal

  • PAllen
  • · Replies 16 ·
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16

Undergrad Does the non-relativistic aberration formula apply to sound or real systems?

  • Kairos
  • · Replies 7 ·
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7

High School Photon Mass: Does Light Have Direction?

  • Lucas Nunes Rosa
  • · Replies 6 ·
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6

Undergrad Information traveling faster than light? (thought experiment)

  • kurosama
  • · Replies 6 ·
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6

Graduate A question on proper time in special relativity

  • user1139
  • · Replies 58 ·
2
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58

Graduate Some algebra in Schutz's textbook

  • MathematicalPhysicist
  • · Replies 12 ·
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12

Undergrad Understanding Papapetrou's Spinning Test Particles in GR

  • ergospherical
  • · Replies 2 ·
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2

Undergrad Violation of Special Relativity Principle?

  • PhysicsTruth
  • · Replies 23 ·
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23

Graduate Gauge invariance and Einstein equations in 11D supergravity

  • ergospherical
  • · Replies 5 ·
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5

Undergrad Is Spacetime Curvature Misunderstood in Eddington's Experiment?

  • Carpe Physicum
  • · Replies 29 ·
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29

Undergrad Why use covariant and contravariant indices in tensor calculus

  • AndersF
  • · Replies 10 ·
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10

Undergrad Parallel Transport of a Tensor: Understand Equation

  • AndersF
  • · Replies 2 ·
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2

Undergrad Time Dilation in Gravitational Fields vs Acceleration on Earth

  • mcgnms
  • · Replies 7 ·
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7

Undergrad Geodesics in Schwarzschild metric

  • Haorong Wu
  • · Replies 42 ·
2
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42

Undergrad Deriving Contravariant Form of Levi-Civita Tensor

  • AndersF
  • · Replies 1 ·
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1

Undergrad Showing Determinant of Metric Tensor is a Tensor Density

  • AndersF
  • · Replies 4 ·
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4

Undergrad Relativity of Simultaneity Questions

  • mucker
  • · Replies 62 ·
3
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62

Undergrad Can a universe have absolute acceleration or absolute velocity?

  • guptasuneet
  • · Replies 18 ·
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18

Undergrad Expressing Vectors of Dual Basis w/Metric Tensor

  • AndersF
  • · Replies 8 ·
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8

Undergrad Does a Magnet Curve Spacetime More Than a Non-Magnetic Mass?

  • Will Learn
  • · Replies 20 ·
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20

Undergrad Why can both perspectives be true in the pole and barn paradox?

  • RH111
  • · Replies 16 ·
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16

Undergrad How does relativistic force and acceleration work in an electrostatic field?

  • MichPod
  • · Replies 3 ·
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3

Undergrad GPS clock synchronization in ECI frame

  • cianfa72
  • · Replies 34 ·
2
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34

Undergrad Mass of Water Increasing with Heating

  • Ebi Rogha
  • · Replies 10 ·
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10

Undergrad FTL Travel: The Matryoshka Paradox

  • Sirius_Prime
  • · Replies 6 ·
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6

High School Reactionless Drive Using Light Bouncing Off Moving Mirrors

  • alas666
  • · Replies 2 ·
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2

Undergrad What is the Meaning of Foliate in Physics and Spacetime?

  • Haorong Wu
  • · Replies 9 ·
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9

High School Do forces reveal the only real inertial frame of reference?

  • Lisastronomy
  • · Replies 7 ·
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7