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 Question About Text: Example 4.1 on Page 35-6

  • mpresic3
  • · Replies 3 ·
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Graduate Interior volume of a black hole

  • PeterDonis
  • · Replies 23 ·
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23

Undergrad Schwarzschild Geometry: Einstein Tensor & Mass Density

  • Joe Prendergast
  • · Replies 18 ·
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18

Undergrad How fast does the particle go through spacetime?

  • student34
  • · Replies 20 ·
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20

High School What is the metric for a bag-of-gold spacetime?

  • Onyx
  • · Replies 9 ·
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9

High School How do Black Holes Grow? A Far-Away Observer's Perspective

  • Rene Dekker
  • · Replies 67 ·
3
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67

Undergrad Inertial Gravity in Relativistic Geodesics - Forum Discussion

  • Thytanium
  • · Replies 11 ·
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11

Undergrad Gravitational field modulation of a moving mass

  • synch
  • · Replies 2 ·
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2

High School Do Gravitational Forces Increase for Objects Moving at Light Speed?

  • Pratyeka
  • · Replies 16 ·
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16

High School Gravity waves and Planck's constant

  • Leonard Begy
  • · Replies 2 ·
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2

High School Speed of Light Reflection: Einstein's Train & Mirrors

  • zasvitim
  • · Replies 38 ·
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38

High School Does Gravitation Start at Black Hole Event Horizon?

  • Shaw
  • · Replies 9 ·
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9

Graduate Origin of BH Entropy & Info Missing Puzzle Resolution

  • sufive
  • · Replies 6 ·
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6

Undergrad Numerical Solution of Complex Systems in GR

  • epovo
  • · Replies 5 ·
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5

Undergrad Sabine Hossenfelder says time dilation is due to acceleration

  • Epic Mythology
  • · Replies 47 ·
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47

Undergrad What is the velocity of a photon through the four dimensions?

  • Epic Mythology
  • · Replies 9 ·
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9

Undergrad Escape from Two Black Holes? Solve the Mystery!

  • Aerodyn
  • · Replies 2 ·
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2

Graduate Why can't we say that photon has very very small mass?

  • Pradyuman
  • · Replies 13 ·
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13

Graduate Minkowski Spacetime 3+1 Dimensions: Conformal Diagram w/Boundary

  • Demystifier
  • · Replies 23 ·
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23

Graduate GW Binary Merger: Riemann Tensor in Source & TT-Gauge

  • MrFlanders
  • · Replies 4 ·
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4

Graduate Special & General Relativity: CTC Metrics in Cylindrical Coordinates

  • YRC
  • · Replies 5 ·
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5

High School A Scenic Trip as a Spaceship at 0.999...c, and questions that arise

  • IroAppe
  • · Replies 36 ·
2
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36

High School The synchronization of clocks and the relativity of motion

  • AlMetis
  • · Replies 84 ·
3
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84

Undergrad Time Paradox: A & B's Clocks Move Differently

  • SaintRodriguez
  • · Replies 6 ·
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6

Undergrad Worldline Curve vs Trajectory: What’s the Difference?

  • SaintRodriguez
  • · Replies 10 ·
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10

High School How do fields retain their uniformity with interposing objects?

  • Clueless123
  • · Replies 4 ·
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4

High School Black Holes: How Do They Move?

  • Clueless123
  • · Replies 22 ·
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22

High School Four Velocity Sign of Time: \dot t>0?

  • Onyx
  • · Replies 3 ·
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3

Graduate Hyperplanes of Simultaneity and BigBang

  • lektroon
  • · Replies 27 ·
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27

Undergrad Universe Expansion: GR vs Hubble Reconciled

  • jeremyfiennes
  • · Replies 5 ·
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5

High School Is Time Dilation About Particle Motion Rather Than Time Itself?

  • teacher94
  • · Replies 53 ·
2
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53

Graduate Solving Geodesics with Metric $$ds^2$$

  • edoofir
  • · Replies 10 ·
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10

Undergrad Can worldlines exist that defy traditional spacetime classifications?

  • SaintRodriguez
  • · Replies 18 ·
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18

High School FRB & Gravitational Wave Link: Scientists Baffled

  • jedishrfu
  • · Replies 4 ·
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4

Undergrad Black holes to explode due to evaporation?

  • HansH
  • · Replies 57 ·
2
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57

Undergrad Do objects gain mass while approaching light speed?

  • LightningInAJar
  • · Replies 25 ·
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25

Insights Why There Are Maximum Mass Limits for Compact Objects

  • PeterDonis
  • · Replies 3 ·
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3

Undergrad Kerr & Nordström Black Hole Evaporation: Q&A

  • snorkack
  • · Replies 3 ·
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3

High School Explaining Distant Time Dilation & Enhanced Gravitation

  • doudou
  • · Replies 4 ·
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4

High School Is Einstein's Space-Time Theory Overfitted or Simply a Visualization Tool?

  • lukephysics
  • · Replies 29 ·
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29

High School The Effect of Binding Energy on Mass

  • Dileep Ramisetty
  • · Replies 5 ·
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5

Undergrad Observed Redshift from Moving Source: Deriving the Result

  • ergospherical
  • · Replies 5 ·
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5

Undergrad Gravitational Field Transformations Under Boosted Velocity

  • Sciencemaster
  • · Replies 14 ·
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14

Undergrad Light-Like Separation: Is It Possible?

  • novice_hack
  • · Replies 4 ·
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4

High School Explaining Galaxy Rotation Speed Discrepancies with GR & Gravitic Fields

  • Sagittarius A-Star
  • · Replies 22 ·
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22

Undergrad How to obtain other inverse metrics than that of Schwarzschild?

  • Bishal Banjara
  • · Replies 50 ·
2
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High School Block universe theory question

  • frankrabbit
  • · Replies 53 ·
2
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53

Undergrad Has anyone measured the speed of light in one direction?

  • OscarCP
  • · Replies 45 ·
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45

High School Spagettification and a singularity

  • HansH
  • · Replies 167 ·
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167

High School The twin paradox and black holes

  • BoraxZ
  • · Replies 31 ·
2
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31

Undergrad Dark Energy Strength in Great Voids of Galaxies

  • Herbascious J
  • · Replies 7 ·
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7

Graduate Solving "const. K" in Gourgoulhon's SR in General Frames

  • Frank Wappler
  • · Replies 4 ·
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4

High School Questions on the Michelson Morley Experiment

  • OneAverageGuy
  • · Replies 47 ·
2
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47

Undergrad Gravitational Field Existence in Void: Philosophical Inquiry

  • Herbascious J
  • · Replies 1 ·
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1

Graduate How Does Linear Framedragging Affect Parallel Moving Masses in Flat Spacetime?

  • BoraxZ
  • · Replies 11 ·
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11

Undergrad Relativity & Simultaneity Convention: Meaning & Impact

  • EclogiteFacies
  • · Replies 12 ·
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12

High School Phase Change in Light: A & B Signal Reflections

  • AlMetis
  • · Replies 31 ·
2
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31

Insights When Discussing the Twin Paradox: Read This First

  • PeterDonis
  • · Replies 2 ·
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2

High School Why Don't We Live Inside a Black Hole?

  • Narasoma
  • · Replies 3 ·
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3

Undergrad Circular Orbit in Schwarzschild: Orbital Period

  • epovo
  • · Replies 5 ·
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5

Undergrad Explore Spacetimes, Metrics & Symmetries in Relativity Theory

  • Suekdccia
  • · Replies 7 ·
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7

Graduate Understanding killing vectors and transformations of metric

  • dwd40physics
  • · Replies 45 ·
2
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45

High School Is Brian or Jim Wrong? (the science of Dr. Who)

  • AtoMick-u235
  • · Replies 10 ·
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10

High School Mick's Spooky Time Dilation Puzzle

  • AtoMick-u235
  • · Replies 3 ·
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3

Graduate Landau's Maximum Mass Limit Derivation in Shapiro & Teukolsky (1983)

  • PeterDonis
  • · Replies 22 ·
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22

Graduate Motivation for Theta = Pi/2 on Wald GR p138

  • strangerep
  • · Replies 5 ·
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5

Undergrad Error in Concepts: Intro to Mechanics Kolenkow & Kleppner

  • Ramanathan k s
  • · Replies 8 ·
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8

Undergrad Can Crafts Reach 2c Relative to Me?

  • Abbott287287
  • · Replies 3 ·
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3

High School What limits the speed of a gravitational wave to c?

  • Rochelobe
  • · Replies 13 ·
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13

High School Relativity of Measures: A vs B Frame & Light Source S

  • AlMetis
  • · Replies 143 ·
5
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143

High School Mechanics behind curved time causing gravitation/geodesics

  • tachi158
  • · Replies 27 ·
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27

High School Speed of light and this Accelerating Rocket scenario

  • John SpaceY
  • · Replies 45 ·
2
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45

Undergrad No Symmetry Spacetimes/Metrics in Theory of Relativity

  • Suekdccia
  • · Replies 7 ·
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7

Undergrad Twin Paradox: Aging Slower with Continuous Acceleration?

  • vibhuav
  • · Replies 13 ·
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13

High School Cherenkov Radiation -- How does this not break causality?

  • peanutaxis
  • · Replies 21 ·
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21

Undergrad Derivation of SR's time-dilatation in 1d?

  • Pony
  • · Replies 60 ·
3
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60

Undergrad What Is the Geometrical Meaning of Principal Null Directions?

  • Umaxo
  • · Replies 3 ·
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3

Graduate Proper Volume on Constant Hypersurface in Alcubierre Metric

  • Onyx
  • · Replies 7 ·
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7

High School Where does the energy of gravity come from?

  • lordoftheselands
  • · Replies 73 ·
3
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73

Undergrad Schwarzschild in Cartesian: Tricks for Transformation

  • epovo
  • · Replies 18 ·
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18

Undergrad Differentiate w/ Respect to Affine Parameter

  • Haorong Wu
  • · Replies 10 ·
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10

Undergrad Understanding Einstein's second postulate of special relativity

  • Erland
  • · Replies 57 ·
2
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57

High School Calculating Fuel Efficiency of Rocket Going Near c

  • Peter564
  • · Replies 2 ·
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2

Undergrad Solving Paradox: Man Running with Pole Reaches Door Before Button is Pressed

  • Jrs580
  • · Replies 27 ·
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27

Undergrad Lack of Symmetry in X & T: Explained for Beginners

  • Chenkel
  • · Replies 13 ·
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13

Undergrad Can time be another basis vector under Galilean relativity?

  • Saw
  • · Replies 146 ·
5
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146

Undergrad Mainstream interpretation of Newton's bucket argument?

  • wisdom
  • · Replies 12 ·
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12

Undergrad Black Holes: Event Horizon Causally Disconnected?

  • Feynstein100
  • · Replies 21 ·
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21

Undergrad Solving Spherically Symmetric Static Star Equations of Motion

  • epovo
  • · Replies 2 ·
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2

Graduate Dirac's Conservation of Matter: A Closer Look

  • Kostik
  • · Replies 7 ·
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7

Undergrad Time dilatopause for black holes

  • Feynstein100
  • · Replies 36 ·
2
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36

Graduate Get GR Tensor II: Where to Buy Program Library

  • toabek
  • · Replies 1 ·
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1

High School How do we identify a stationary system?

  • CClyde
  • · Replies 43 ·
2
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43

High School A thought experiment of the relativity of light

  • CClyde
  • · Replies 76 ·
3
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76

Undergrad Doppler Effect on Light: Constant Speed of Light Confusion

  • InquiringMind
  • · Replies 9 ·
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9

Undergrad Time Dilation Paradox: Geosynchronous Satellites

  • InquiringMind
  • · Replies 5 ·
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5

Graduate Why are General relativity texts so much more formal?

  • paralleltransport
  • · Replies 28 ·
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28

Undergrad How to rule out that the speed of light was different in the past?

  • victorvmotti
  • · Replies 76 ·
3
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76

High School Find Geodesics in Dynamic Ellis Orbits Metric

  • Onyx
  • · Replies 92 ·
4
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92

Undergrad How meaningful is the notion of now here on Earth?

  • EclogiteFacies
  • · Replies 1 ·
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1