Special and General Relativity Forum

Post thread
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.
Undergrad Reconciling Simultaneity & Relativity: Navigating the Spacetime Maze
  • · Replies 8 ·
Replies
8
Views
2K
Undergrad Black Hole & Spacetime Curvature: Can Mass Decrease It?
  • · Replies 4 ·
Replies
4
Views
2K
Undergrad Time Dilation Explained: Muon Decay & Reaching Earth
  • · Replies 3 ·
Replies
3
Views
2K
High School Who Compresses More: Obj1 or Obj2 at C Speeds?
  • · Replies 11 ·
Replies
11
Views
2K
High School Twin Paradox Visualization: Understanding with Java & Diagrams
  • · Replies 5 ·
Replies
5
Views
3K
Undergrad SR Pseudo-Paradox: Photons Affected by Emitter?
  • · Replies 4 ·
Replies
4
Views
2K
High School Some basic questions about length contraction in SR
  • · Replies 16 ·
Replies
16
Views
2K
Undergrad Time Dilation & Differential Aging: Defined
  • · Replies 4 ·
Replies
4
Views
2K
High School Crashing into an event horizon
  • · Replies 20 ·
Replies
20
Views
2K
Undergrad Could it be meaningful to speak of the "density of space"?
  • · Replies 18 ·
Replies
18
Views
3K
Undergrad Is there any 2D surface whose metric tensor is eta?
  • · Replies 4 ·
Replies
4
Views
1K
High School Deriving Special Relativity Formulae Steps
  • · Replies 4 ·
Replies
4
Views
2K
High School Question about Michelson-Morley experiment
  • · Replies 29 ·
Replies
29
Views
7K
Undergrad Quantum Mechanics & Relativity: Vacuum Connection?
  • · Replies 5 ·
Replies
5
Views
2K
High School Understand Proper Distances in SR/GR: A Layman's Guide
  • · Replies 11 ·
Replies
11
Views
2K
Undergrad Relativistic Momentum Invariance in Perpendicular Boosts
  • · Replies 3 ·
Replies
3
Views
1K
Undergrad Galilean Equivalence Principle: Extended Objects
  • · Replies 8 ·
Replies
8
Views
2K
Undergrad Fixed Stars Moving Faster Than Light? Problem?
  • · Replies 6 ·
Replies
6
Views
1K
Undergrad Opposite of Black Hole - Matter Repulsion?
  • · Replies 3 ·
Replies
3
Views
2K
Graduate Interpretation of [itex]\partial_\nu T^{\mu \nu}[/itex]
  • · Replies 8 ·
Replies
8
Views
3K
Undergrad Special relativity of two clocks
  • · Replies 4 ·
Replies
4
Views
2K
High School Does time stop at the center of a black hole?
  • · Replies 16 ·
Replies
16
Views
3K
High School Connected events at opposite ends of a photon's travel
  • · Replies 24 ·
Replies
24
Views
3K
Graduate How Does the Penrose Process Allow for Energy Extraction from a Black Hole?
  • · Replies 3 ·
Replies
3
Views
2K
Graduate Which Representation of Christoffel Symbols is Correct?
  • · Replies 14 ·
Replies
14
Views
3K
Graduate Deriving Einstein's Equation: Calculating ##R_{00}##
  • · Replies 2 ·
Replies
2
Views
1K
High School Derivation of E=Mc2? For the common man
  • · Replies 3 ·
Replies
3
Views
2K
High School What Does it Mean When a Black Hole is Spinning?
  • · Replies 10 ·
Replies
10
Views
2K
Undergrad Small back hole merging more massive body
  • · Replies 6 ·
Replies
6
Views
1K
Undergrad Looking out from a event horizon
  • · Replies 18 ·
Replies
18
Views
3K
Undergrad Gravitational Mass of Photons: Passive & Active
  • · Replies 7 ·
Replies
7
Views
2K
High School Time Dilation Model & Wave Interference: Newbie Questions Answered
  • · Replies 2 ·
Replies
2
Views
1K
High School How well is Time understood i. Space time?
  • · Replies 4 ·
Replies
4
Views
1K
High School Space-Time & Strings: Current Thinking?
  • · Replies 1 ·
Replies
1
Views
1K
Insights A Problem from "Incandescence" - Comments
  • · Replies 4 ·
Replies
4
Views
2K
Graduate Einstein & Light Deviation: Compute w/o Schwarzschild Metric
  • · Replies 4 ·
Replies
4
Views
2K
Undergrad Do Fields Affect 4-Momentum Conservation?
  • · Replies 4 ·
Replies
4
Views
1K
Undergrad Time dilation in special vs. general relativity
  • · Replies 10 ·
Replies
10
Views
3K
Undergrad Maxwell's Homogeneous Eqns: Notation Explained | Mick
  • · Replies 2 ·
Replies
2
Views
1K
Undergrad How Do You Correctly Apply Indices in Tensor Calculus for Curvature?
  • · Replies 3 ·
Replies
3
Views
1K
Graduate Stress-Energy Tensor: Basics & Questions
  • · Replies 3 ·
Replies
3
Views
2K
High School Calculating Mass for Gravitational Time Dilation
  • · Replies 4 ·
Replies
4
Views
3K
High School Gravity Effects on EM Wave Phase Change
  • · Replies 8 ·
Replies
8
Views
2K
Graduate Are temperature and pressure related by relativity?
  • · Replies 3 ·
Replies
3
Views
2K
Graduate Conservation of Electromagnetic Energy-Momentum Tensor
  • · Replies 1 ·
Replies
1
Views
3K
Undergrad Light Beam Bending by Mass: Equation & Explanation
  • · Replies 2 ·
Replies
2
Views
1K
Undergrad Tensor Formalism in GR: Why We Need Tensors
  • · Replies 12 ·
Replies
12
Views
2K
Undergrad Permeability/permittivity constants and one way speed of c
  • · Replies 14 ·
Replies
14
Views
3K
Undergrad Raising index on covariant derivative operator?
  • · Replies 15 ·
Replies
15
Views
7K
High School Do Higher-Dimensional Objects Experience Length Contraction in 3D Space?
  • · Replies 9 ·
Replies
9
Views
1K
Undergrad Qs re Hawking Radiation – Part I
  • · Replies 4 ·
Replies
4
Views
2K
High School Why r=0 is inevitable when crossing horizon?
  • · Replies 9 ·
Replies
9
Views
2K
Undergrad Hawking Radiation: Qs re Energy Density at r > Rc
  • · Replies 9 ·
Replies
9
Views
2K
Undergrad 2D Time dilation simulation with several clocks?
  • · Replies 12 ·
Replies
12
Views
2K
Undergrad Cosmological Constant: Expanding Universe & Data Contradiction
  • · Replies 4 ·
Replies
4
Views
2K
Undergrad Space and time as fields of mass-energy
  • · Replies 8 ·
Replies
8
Views
2K
Graduate Subtraction of Christoffel symbol
  • · Replies 8 ·
Replies
8
Views
2K
Undergrad Field equations fully written out
  • · Replies 3 ·
Replies
3
Views
5K
Undergrad GR vs SR: Is a Connection Necessary?
  • · Replies 5 ·
Replies
5
Views
2K
Undergrad Consequences of length contraction
  • · Replies 18 ·
Replies
18
Views
3K
Undergrad Gravitational potential energy and rest mass
  • · Replies 19 ·
Replies
19
Views
4K
Undergrad Time dilation in relativistic Doppler effect
  • · Replies 21 ·
Replies
21
Views
3K
High School Energy required to change speed?
  • · Replies 5 ·
Replies
5
Views
2K
Graduate Are Killing Horizon and Stationary Limit Surface the same?
  • · Replies 30 ·
2
Replies
30
Views
5K
High School How to simply solve for E=MC^2?
  • · Replies 13 ·
Replies
13
Views
3K
Graduate Why Do Torsion Tensor Derivations Differ Between Sources?
  • · Replies 29 ·
Replies
29
Views
6K
High School Gravity & Acceleration: Is Space Shortening Explained?
  • · Replies 14 ·
Replies
14
Views
2K
Undergrad Calculating Radius and Mass of Disc for Velocity 0.75C
  • · Replies 9 ·
Replies
9
Views
2K
Graduate Anti-symmetric Christoffel symbol
  • · Replies 6 ·
Replies
6
Views
3K
Graduate Interpretation of the EM tensor as a rotation matrix
  • · Replies 8 ·
Replies
8
Views
3K
High School Virtual Particle Speed: Is It Measurable?
  • · Replies 3 ·
Replies
3
Views
1K
Graduate Curvature tensor in all flat space coordinates
  • · Replies 4 ·
Replies
4
Views
2K
High School Einstein's Greatest Mistake? Examining the Lorentz Transformation
  • · Replies 11 ·
Replies
11
Views
2K
High School Rod falling radially towards the center of a mass
  • · Replies 58 ·
2
Replies
58
Views
6K
Undergrad Is the universe a larger version of a black hole?
  • · Replies 2 ·
Replies
2
Views
2K
High School Can gravitational wave escape a black hole
  • · Replies 12 ·
Replies
12
Views
3K
Undergrad MOND: Explaining the “Missing Mass” Problem in Galaxies
  • · Replies 4 ·
Replies
4
Views
2K
Undergrad Metric Conservation Law in 2D Spacetime
  • · Replies 2 ·
Replies
2
Views
1K
Undergrad Do Distant Planets Move Faster Than Light Seen From Earth?
  • · Replies 8 ·
Replies
8
Views
2K
Graduate Q: Scalar Boundary Condition & U(1) Isometry - Lewkowycz & Maldacena
  • · Replies 1 ·
Replies
1
Views
1K
High School Can a Spaceship Use a Planet's Gravity Like a Treadmill?
  • · Replies 2 ·
Replies
2
Views
2K
Graduate What is the coordinate free stress-energy-momentum tensor
  • · Replies 6 ·
Replies
6
Views
3K
Undergrad Velocity of Timelike Curve in Special Relativity
  • · Replies 3 ·
Replies
3
Views
2K
Undergrad Clarifying Equivalence Principle
  • · Replies 18 ·
Replies
18
Views
3K
Graduate Field of Moving Masses: EM Purcell
  • · Replies 4 ·
Replies
4
Views
1K
Undergrad Taylor and Wheeler's Spacetime Physics (1st Edition)
  • · Replies 4 ·
Replies
4
Views
3K
High School The Nature of Light: A Scientific Exploration.
  • · Replies 29 ·
Replies
29
Views
3K
Graduate Was the LIGO team over-hasty to claim black holes confirmed?
  • · Replies 4 ·
Replies
4
Views
2K
Undergrad Morin's Rocket Example: Chapter 12, Page 606
  • · Replies 8 ·
Replies
8
Views
2K
High School Why do gravitational waves propagate at the speed of light?
  • · Replies 4 ·
Replies
4
Views
2K
Graduate Mapping Tangent Space to Manifold - Questions & Answers
  • · Replies 3 ·
Replies
3
Views
2K
High School Understanding the Sign of Relative Velocity in Approaching Observers
  • · Replies 10 ·
Replies
10
Views
3K
High School Kinetic Energy Dependent on Frame of Reference?
  • · Replies 4 ·
Replies
4
Views
2K
High School Black Hole SHM: Gravitational Force
  • · Replies 3 ·
Replies
3
Views
1K
Undergrad Show 4-Potential is 4-Vector in Lorenz Gauge
  • · Replies 3 ·
Replies
3
Views
2K
Graduate Least Action Principle Applied to Vector Field ##A_{\mu}##
  • · Replies 3 ·
Replies
3
Views
1K
Undergrad Speed of light or Speed limit of Spacetime?
  • · Replies 18 ·
Replies
18
Views
2K
High School Time travel with tachyons cause infinite dilemma?
  • · Replies 10 ·
Replies
10
Views
2K
Undergrad Communicating at Near-Light Speed - Time Dilation
  • · Replies 5 ·
Replies
5
Views
2K
Undergrad Motivation for the usage of 4-vectors in special relativity
  • · Replies 32 ·
2
Replies
32
Views
5K