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

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12

Undergrad What is the relative speed of an object standing still on Earth?

  • yogiwp
  • · Replies 18 ·
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18

Graduate If Time and Space Are Relative Concepts, Then

  • Curious6
  • · Replies 17 ·
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17

Graduate Interpretation of GR: Einstein vs. Contemporary Physicists

  • humanino
  • · Replies 6 ·
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6

Graduate Schwarzschild metric and BH mass

  • kurious
  • · Replies 78 ·
3
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78

Graduate Is Block Time in General Relativity Proof of a Fixed Future or Many-Worlds?

  • Gerinski
  • · Replies 23 ·
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23

Graduate The End of the Universe from the Outside In - as free-faller nears singularity

  • Ray Eston Smith Jr
  • · Replies 2 ·
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2

Undergrad Is Gravitational Red-Shift a Valid Concept?

  • Entropy
  • · Replies 13 ·
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13
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25

Graduate Why can't we use a photon's frame of reference?

  • JoeWade
  • · Replies 44 ·
2
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44

Graduate How Does Earth's Rotation Speed Influence Frame Dragging Effects?

  • kurious
  • · Replies 2 ·
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2

Graduate How Do Time Cones Illustrate the Concept of Space-Time?

  • Gale
  • · Replies 2 ·
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2

Undergrad Evidence of length contraction

  • Adam
  • · Replies 7 ·
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7

Graduate Do Wormholes Require Antimatter Singularities to Function?

  • chosenone
  • · Replies 19 ·
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19

Graduate Bee Swarm Relativity: Calculating Time with a Messenger Bee

  • Vern
  • · Replies 2 ·
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2

Graduate Spaceship accelerating inside a Black Hole

  • quasar987
  • · Replies 7 ·
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7

Graduate Clarifications on time in various physics models

  • Olias
  • · Replies 2 ·
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2

High School Older faster if the universe wouldn't be expanding?

  • niko2000
  • · Replies 4 ·
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4

Graduate There is only one True Singularity and It is at the Center

  • Ray Eston Smith Jr
  • · Replies 43 ·
2
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43

Graduate What is a time-like killing vector?

  • kurious
  • · Replies 4 ·
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4

Graduate What is the Unverifiable Nature of Black Hole Internal States?

  • blue_sky
  • · Replies 6 ·
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6

Graduate Why does gravity rotate with the Earth?

  • Gfoxboy
  • · Replies 8 ·
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8

Graduate Change in relativistic momentum

  • kurious
  • · Replies 5 ·
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5

Undergrad How can we know what distant objects looked like if they're moving away?

  • dcbobo
  • · Replies 33 ·
2
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33

Undergrad Gravitation Speed/Acceleration/Velocity

  • Olias
  • · Replies 7 ·
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7

Graduate Why is action at a distance ruled out in gravity but allowed in quantum entanglement?

  • wolram
  • · Replies 4 ·
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4

Graduate What software do people use for tensor manipulation in general relativity?

  • pervect
  • · Replies 2 ·
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2

Graduate E = mc^2: Identity or equality

  • pmb_phy
  • · Replies 2 ·
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2

Graduate Is gravity really just acceleration? And what about gravitons?

  • mee
  • · Replies 2 ·
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2

Graduate Where are we on gravitational waves/graviton?

  • quasar987
  • · Replies 6 ·
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6

Graduate Calculating mass and speed from kinetic energy and linear momentum

  • niko2000
  • · Replies 12 ·
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12

Undergrad Does Gravity Expand and Collapse or is it Always Present?

  • Zeteg
  • · Replies 3 ·
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3

Graduate Special Relativity. timespace correlation.

  • mlip
  • · Replies 10 ·
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10

Undergrad Is Einstein's Theory of Relativity Flawed?

  • A 15 year old
  • · Replies 76 ·
3
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76

Graduate Can particles traveling near the speed of light create a time reversal effect?

  • John_M
  • · Replies 28 ·
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28

Graduate How Does Dark Energy Exert Pressure in the Universe?

  • kurious
  • · Replies 5 ·
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5

Graduate Event Horizon vs Singularity: Are They the Same Thing in Black Hole Physics?

  • Ray Eston Smith Jr
  • · Replies 2 ·
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2

Graduate What Determines the Direction of Space Curvature by Mass in General Relativity?

  • Erus
  • · Replies 6 ·
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6

Graduate Why does cosmic background radiation appear lower frequency on Earth?

  • J79
  • · Replies 12 ·
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12

Graduate Do matter and event horizon stay at fixed distance from distant objects?

  • Ray Eston Smith Jr
  • · Replies 7 ·
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7

Graduate Can two events be perceived in reverse order due to relativistic effects?

  • Gerinski
  • · Replies 7 ·
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7

Graduate Escape velocity outside event horizon

  • Ray Eston Smith Jr
  • · Replies 6 ·
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6

Graduate Can a falling feather inside a rocket ship create a black hole?

  • Ray Eston Smith Jr
  • · Replies 6 ·
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6

Undergrad Why Doesn't a Photon's Energy Knock Us Out?

  • CBR600RR
  • · Replies 35 ·
2
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35

Graduate Conservation of energy in GR and symmetry

  • kurious
  • · Replies 12 ·
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12

Graduate Can an Accelerating Universe Rotate According to GR Principles?

  • blue_sky
  • · Replies 14 ·
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14

Graduate FTL travel and going to the past in spacetime diagrams

  • Gerinski
  • · Replies 7 ·
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7

Graduate Do black holes have zero spatial radius at the event horizon?

  • Ray Eston Smith Jr
  • · Replies 9 ·
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9

Graduate Those who use relativistic mass and why

  • pmb_phy
  • · Replies 89 ·
3
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89

Graduate Are There Any Alternative Models to Explain Gravity?

  • Tom McCurdy
  • · Replies 2 ·
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2

Graduate Stresses in a rotating object?

  • billyboy
  • · Replies 2 ·
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2

Graduate Measuring the Speed of Light from Distant Sources: How Do We Know It's Constant?

  • Prometheus
  • · Replies 4 ·
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Graduate Is time relative motion of matter or a human construct?

  • what_are_electrons
  • · Replies 2 ·
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Graduate So we have problems with clocks measureing time ?

  • Doctordick
  • · Replies 215 ·
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Undergrad How can we explain special relativity to skeptics?

  • VantagePoint72
  • · Replies 13 ·
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13

Undergrad Solving the Twins Paradox: Could Einstein be Wrong?

  • Gfoxboy
  • · Replies 8 ·
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8

Graduate Can an Arbitrary Co-ordinate System Be Used for Observers in GR?

  • blue_sky
  • · Replies 12 ·
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12

Graduate The fundenental law of relativity

  • C. Michael Turner
  • · Replies 21 ·
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21

Graduate Oh My God Particle - Fourmilab

  • whydoyouwanttoknow
  • · Replies 2 ·
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2

Undergrad Is Time Travel Backwards Theoretically Possible?

  • ArmoSkater87
  • · Replies 7 ·
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7

Graduate Solving a Random Equation: a=dt_o/t^3sqrt(1-v^2/c^2)

  • IooqXpooI
  • · Replies 4 ·
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4

Graduate Infinitie tidal forces at event horizon?

  • Ray Eston Smith Jr
  • · Replies 3 ·
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3

Graduate Why does η^μβ h_νσ,β = h_νσ^,μ in general relativity?

  • da_willem
  • · Replies 12 ·
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12

Graduate Can Special Relativity's Equations Be Modified to Avoid Infinities and Zeroes?

  • kurious
  • · Replies 25 ·
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25

Graduate Relative velocity of two spaceships moving perpendicular to each other

  • niko2000
  • · Replies 11 ·
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11

Graduate Velocity of one spacecraft relative to another at relativistic speeds

  • relativitydude
  • · Replies 5 ·
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5

What Would Sound Like at the Speed of Light?

  • NiceJerkGuy
  • · Replies 5 ·
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5

Graduate Spacetime and Euclidean Geometry-Jacobson

  • Olias
  • · Replies 2 ·
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2

Graduate Speed light travels on earth and in our solar system

  • Hat_Man
  • · Replies 2 ·
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2

Graduate Why does the metric tensor have 3 parameters per spatial dimension?

  • Entropy
  • · Replies 3 ·
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3

Graduate Practical Use For Length Contraction?

  • zoobyshoe
  • · Replies 13 ·
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13

Graduate Can Humans See Bodies Traveling at the Speed of Light?

  • Sana
  • · Replies 26 ·
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26

Graduate Latest Developments on Black and White Hole-Theory and Anti-Gravity

  • marlon
  • · Replies 10 ·
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10

Graduate Matter <--> Energy Conversions: A Phase Transition?

  • Glenn
  • · Replies 4 ·
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4

Graduate Can Matter and Energy Truly Be Annihilated According to Relativity?

  • Erus
  • · Replies 7 ·
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7

Graduate Do Gravitons Play a Role in Simulated Gravity on a Rotating Spacestation?

  • Glenn
  • · Replies 3 ·
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3

Graduate Do Einstein's Theories of Relativity Contradict Each Other?

  • Garth
  • · Replies 70 ·
3
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70

Graduate What is the nature of mass and its relationship to movement?

  • Vern
  • · Replies 33 ·
2
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33

Graduate Does relativistic mass have a gravitational component?

  • j8hart
  • · Replies 60 ·
3
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60

Graduate Is Time a Mobius Dimension in Relativity Theory?

  • Neo
  • · Replies 8 ·
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8

Graduate The Pinwheel Paradox: What's the Solution?

  • Zanket
  • · Replies 19 ·
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19

Graduate What conditions must a universe model satisfy to be viable?

  • Gale
  • · Replies 17 ·
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17

Graduate Does wave-particle duality emerge at relativistic speeds?

  • Neo
  • · Replies 5 ·
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5

Undergrad How Does Water Slow Down Light Without Violating Special Relativity?

  • Jake
  • · Replies 2 ·
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2

Graduate Can I learn general relativity from Schutz before upper division physics?

  • Gza
  • · Replies 22 ·
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22

Graduate Does G.Relativity Violate Energy Basics?

  • omin
  • · Replies 27 ·
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27

Graduate Why is the speed of light constant for all observers?

  • Reflector
  • · Replies 105 ·
4
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105

Graduate Correction to length contraction equation

  • kurious
  • · Replies 35 ·
2
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35

Graduate Can simultaneous events in one frame trigger different outcomes in another?

  • John_M
  • · Replies 11 ·
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11

Graduate How Does Einstein's Theory Explain the Nature of Space?

  • omin
  • · Replies 22 ·
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22

Graduate Is a change in earth's surface gravity detectable?

  • Creator
  • · Replies 9 ·
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9

Graduate Does light produce gravitational effects in general relativity?

  • woodysooner
  • · Replies 28 ·
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28

Graduate What is the Entropy Value of a 5 Solar Mass Black Hole?

  • kurious
  • · Replies 2 ·
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2

High School The difference b/t free fall and outer space

  • HungryChemist
  • · Replies 2 ·
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2

Graduate Length Contraction and the Bomb Paradox

  • HungryChemist
  • · Replies 7 ·
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7

Graduate What is the Speed of Light, Dark Matter?

  • jaguar99
  • · Replies 2 ·
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2

Graduate Do observers in different frames agree on an object's energy?

  • Moose352
  • · Replies 40 ·
2
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40

Graduate Does a ruler attached tangent to a rotating wheel contract?

  • Silverious
  • · Replies 9 ·
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9

Undergrad What Starter Texts Can Help Understand Differential Geometry for GTR?

  • srp
  • · Replies 6 ·
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6

Graduate Do magnetic or electrostatic forces resist spacetime expansion?

  • wolram
  • · Replies 3 ·
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3