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

Insights Principle explanations of modern physics mysteries

  • RUTA
  • · Replies 131 ·
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131

Undergrad Relative Speed of Light Between Objects

  • Skaperen
  • · Replies 3 ·
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3

Undergrad Does a star's mass cause gravitational redshift of its own light?

  • gptejms
  • · Replies 26 ·
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26

Undergrad Questions regarding traveling speed in time and gravity as a force

  • ffp
  • · Replies 95 ·
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95

Undergrad Does Special Relativity Affect Mass?

  • The_Baron
  • · Replies 1 ·
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1

Undergrad What does general relativity explain beyond its basic assumptions?

  • ohwilleke
  • · Replies 22 ·
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22

Undergrad Can You Derive \(T^{\mu\nu}\) From the Given Lagrangian?

  • samalkhaiat
  • · Replies 6 ·
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6

Undergrad Transpose and Inverse of Lorentz Transform Matrix

  • devd
  • · Replies 89 ·
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89

Undergrad Schwarzschild Metric Singularity: Why?

  • Charles_Xu
  • · Replies 4 ·
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4

High School Does gravitational time dilation cause gravity according to Greene's Hidden Reality?

  • Curious Cat
  • · Replies 26 ·
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26

Undergrad Force on scale from car moving relativistically in accelerating rocket

  • Sagittarius A-Star
  • · Replies 33 ·
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33

Graduate Some questions about the derivation steps in the Gravitational deflection of light section in Schutz

  • MathematicalPhysicist
  • · Replies 2 ·
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2

High School How do we know what would happen if time reversed?

  • olamosey
  • · Replies 1 ·
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1

High School Derive Special Relativity: Alternative Paths

  • user_12345
  • · Replies 7 ·
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7

Graduate Can the geodesic equation be derived from the EFE in a certain limit?

  • john baez
  • · Replies 40 ·
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40

High School What is the distance at which gravity and the cosmological force are equal?

  • J O Linton
  • · Replies 46 ·
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46

Undergrad Equivalence principle question

  • mucker
  • · Replies 36 ·
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36

Undergrad Why can't you define a position vector in curved spacetime?

  • NSRG
  • · Replies 8 ·
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8

High School How does cosmic expansion affect a neutron's energy and momentum?

  • J O Linton
  • · Replies 11 ·
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11

High School Do photons in a perfectly reflecting box experience cosmological redshift?

  • J O Linton
  • · Replies 132 ·
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132

High School How Do Points M and O' Move Relative to Point O in Space and Time?

  • ilasus
  • · Replies 25 ·
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25

High School Faster than speed of light due to time dilation?

  • Drizy
  • · Replies 27 ·
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27

Undergrad Gravity at Schwarzschild Radius of a Black Hole

  • Roberto Pavani
  • · Replies 17 ·
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17

Undergrad Deriving Lorentz transformations from relative motion of three objects

  • ilasus
  • · Replies 53 ·
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53

Undergrad Is Covariant Derivative Notation Misleading in Vector Calculus?

  • stevendaryl
  • · Replies 124 ·
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124

High School Is Relativity the Evolution of Classical Physics?

  • askor
  • · Replies 9 ·
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9

Undergrad What variables affect time dilation besides speed and gravity?

  • LightningInAJar
  • · Replies 7 ·
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7

Undergrad Left Invariant Metric: What I Don't Understand

  • ergospherical
  • · Replies 2 ·
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2

High School Okay, so is Mach's principle true, or not?

  • Paige_Turner
  • · Replies 6 ·
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6

Undergrad Interior Schwarzschild proper length and Gaussian curvature

  • D.S.Beyer
  • · Replies 2 ·
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2

Undergrad Gravity: Introduction to Einstein's General Relativity

  • marco_shaw
  • · Replies 1 ·
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1

Undergrad A short derivation of the relativistic forms of energy and momentum

  • stevendaryl
  • · Replies 36 ·
2
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36

Undergrad Wavelength of Light Ray Affected by Gravity

  • GeniVasc
  • · Replies 7 ·
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7

High School Need to Check GR Beliefs? Integrity Filter Here!

  • Paige_Turner
  • · Replies 27 ·
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27

High School Why Does Mass Pull on Other Stuff?

  • Paige_Turner
  • · Replies 15 ·
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15

Undergrad How do forces change with speed?

  • Hyperspaced
  • · Replies 3 ·
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3

High School Light Speed Traveling: Cosmic Background Radiation Effects

  • David Lewis
  • · Replies 9 ·
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9

High School Gravitational Lensing: Refraction or Something Else?

  • Paige_Turner
  • · Replies 4 ·
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4

Undergrad Derive Escape Velocity GR: Source for Schwarzschild Metric

  • snoopies622
  • · Replies 7 ·
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7

High School Does negative gravitational energy cancel a pendulum's upward momentum?

  • Paige_Turner
  • · Replies 2 ·
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2

Undergrad Why is the spacetime interval computed as distance squared minus time squared?

  • Paige_Turner
  • · Replies 14 ·
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14

Undergrad If gravity is not a force, what is holding us down?

  • sawer
  • · Replies 61 ·
3
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61

High School Does Jim Woodward's MEGA drive violate conservation of momentum?

  • Randy Subers
  • · Replies 8 ·
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8

Undergrad Why should the time component of 4-momentum equal energy?

  • George Keeling
  • · Replies 14 ·
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14

Undergrad Calculating Covariant Derivative of Riemann Tensor in Riemann Normal Coordinates

  • minits
  • · Replies 5 ·
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5

High School Explanation of light speed limit

  • Thecla
  • · Replies 9 ·
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9

High School Why does a traveling observer see your time slow down if yours slows for them?

  • AdvaitDhingra
  • · Replies 10 ·
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Undergrad Coordinate System for Minkowskian Spacetime Relative to Event

  • Halc
  • · Replies 8 ·
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8

Undergrad General relativistic comparison to Newtonian physics

  • Myslius
  • · Replies 21 ·
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21

Undergrad What is the confusion surrounding time as a coordinate in general relativity?

  • AHSAN MUJTABA
  • · Replies 23 ·
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23

Graduate What makes black hole horizons crossable but FLRW horizons not?

  • Bandersnatch
  • · Replies 9 ·
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9

Undergrad Stress-Energy of Star Collapsing into Black Hole

  • timmdeeg
  • · Replies 13 ·
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13

Graduate Fluid Flow Symmetry: Showing $\pi_b G^b$ is Constant

  • ergospherical
  • · Replies 4 ·
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4

Graduate Thermality vs non-thermality in Hawking-Unruh radiation

  • bukhari
  • · Replies 1 ·
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1

Undergrad "Testing the black-hole area law with GW150914"

  • robphy
  • · Replies 0 ·
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0

Undergrad Calculating Time Elapsed in Rocket Collision

  • Abhishek11235
  • · Replies 18 ·
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18

Graduate Geodesic Expansion: Finding the $\theta_{\pm}$ Factor

  • ergospherical
  • · Replies 2 ·
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2

High School Sine-Gordon model for better understanding of special relativity?

  • Jarek 31
  • · Replies 14 ·
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14

Undergrad Do electromagnetic fields curve space-time like gravity does?

  • crastinus
  • · Replies 13 ·
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13

Undergrad What is gradient energy in scalar field theory?

  • Haorong Wu
  • · Replies 5 ·
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5

Graduate Gravitational Quadrupole Formula: Polarization Tensor

  • pervect
  • · Replies 4 ·
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4

High School What Drives the Acceleration of the Universe's Expansion?

  • jeremyfiennes
  • · Replies 6 ·
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6

Undergrad Transforming a circular orbit to a different reference frame

  • Killtech
  • · Replies 12 ·
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12

Undergrad Does the Topology of AdS4 Affect Global Hyperbolicity?

  • ergospherical
  • · Replies 5 ·
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5

Undergrad The bending of starlight is twice the Newtonian prediction

  • J O Linton
  • · Replies 90 ·
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90

Graduate Computing Null Geodesics in Schwarzschild Geometry

  • stevendaryl
  • · Replies 4 ·
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4

Graduate Expressing Lie derivatives of vectors and tensors using covariant derivatives

  • Arman777
  • · Replies 11 ·
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11

Undergrad Light clock simulator app for special and general relativity

  • joekahr
  • · Replies 2 ·
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2

High School Time Dilation Effect: Corrections to Clocks on ISS

  • saddlestone-man
  • · Replies 5 ·
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5

High School SR equation seems to depend on orientation of the 'light clock'

  • bwana
  • · Replies 65 ·
3
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65

High School Is E=mc^2 a Bidirectional Equation in Physics?

  • saddlestone-man
  • · Replies 70 ·
3
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70

Undergrad Does charging my phone increase its gravitational force?

  • Ebi
  • · Replies 3 ·
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3

Undergrad When does correlation become causation?

  • entropy1
  • · Replies 28 ·
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28

Undergrad When are two manifolds equivalent under coordinate transformation?

  • Will Learn
  • · Replies 16 ·
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16

Undergrad Equation for orbital energy loss from gravitational waves

  • Buzz Bloom
  • · Replies 6 ·
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6

Undergrad GR: Can Units Tell You if Quantity is Covariant or Contravariant?

  • Twigg
  • · Replies 3 ·
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3

High School What Is the Proper Time of the CMB and Its Implications?

  • D.S.Beyer
  • · Replies 9 ·
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9

High School Time like spacetime interval, proper time, and time dilation

  • Point Conception
  • · Replies 37 ·
2
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37

Graduate Deriving absolute time dilation for the Kerr metric

  • Dukon
  • · Replies 19 ·
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19

Undergrad How Does the Twin Paradox Apply to Light and Sound Waves?

  • Killtech
  • · Replies 48 ·
2
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48

Graduate Gravitational field of an infinite flat slab

  • Ibix
  • · Replies 14 ·
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14

High School What Happens to Time and Space Near a Black Hole's Event Horizon?

  • Roberto Pavani
  • · Replies 3 ·
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3

Graduate Is there a simple equation for finding Killing vectors of any metric?

  • Arman777
  • · Replies 12 ·
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12

Undergrad C in a Vacuum: Evidence of Constant?

  • pkc111
  • · Replies 7 ·
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7

Undergrad What observable quantity corresponds to boost generators?

  • nicholas_eng
  • · Replies 1 ·
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1

Undergrad Why don't train observers age differently if their clocks lag in the ground frame?

  • Grasshopper
  • · Replies 20 ·
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20

Graduate Can you sum stress-energy tensors in Einstein's nonlinear gravitational theory?

  • empdee4
  • · Replies 15 ·
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15

Undergrad Can mechanical waves travel faster than EM waves in some medium?

  • Barblorrane
  • · Replies 1 ·
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1

Undergrad Twin Paradox: Spacetime Physics Ch.4 & 202 Year Difference

  • Office_Shredder
  • · Replies 27 ·
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27

High School Does relativistic mass increase with velocity?

  • Victorifrj
  • · Replies 41 ·
2
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41

Undergrad Configuring Laws of Motion: Static/Dynamic

  • Maniac_XOX
  • · Replies 1 ·
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1

Undergrad Could spacetime be non-orientable?

  • Jarek 31
  • · Replies 49 ·
2
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49

Undergrad Summation notation and general relativity derivatives

  • Maniac_XOX
  • · Replies 38 ·
2
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38

Undergrad Proca equation with nonlinear operator A²∂·A

  • Maniac_XOX
  • · Replies 44 ·
2
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44

Undergrad Does Time Slow Down in a Deep Osmium Room?

  • alpha_michi
  • · Replies 31 ·
2
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31

Undergrad Deriving equations of motion from a modified Lagrangian with vector field coupling

  • Maniac_XOX
  • · Replies 11 ·
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11

Undergrad Why does length contraction have an extraneous solution l=1?

  • Office_Shredder
  • · Replies 33 ·
2
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33

High School Will a relativistic helium balloon fall if it contracts denser than air?

  • Freaky Fred
  • · Replies 17 ·
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17

Undergrad What exactly was Lorentz ether theory?

  • bhobba
  • · Replies 1 ·
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1

Undergrad Riemann Curvature: Understanding Parallel Transport on 1D Rings

  • Narasoma
  • · Replies 2 ·
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2