Special and General Relativity Forum

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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 Time-Like Events: Spatial Order Not Relevant?
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Undergrad Is this just a typo in Schutz' book on General Relativity?
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Undergrad Metrics of GR Solutions: Comp List, Hist & Viability
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Undergrad Linearized Gravity: Bimetric Theory of General Relativity?
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Undergrad Can Spherical Symmetry Be Achieved Without Varying Line Element?
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Undergrad How is photon momentum compatible with special relativity?
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Undergrad Do AEST (Absolute Euclidean Spacetime) models work?
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Undergrad Hawking Radiation Extrapolation: A Conjecture
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Undergrad Hawking Radiation: Can Particles Appear with Relativistic Velocities?
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Undergrad Time Dilation & Length Contraction: Graphically Explained
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Undergrad Time Dilation in Gravitational Field: Potential vs Field Strength
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Undergrad Observing a Collapsing Shell: Time Dilation Explained
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Undergrad Time Dilation for Photons: Explained
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Undergrad Cosmic Test Reveals Odd Findings for Einstein's Relativity
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Undergrad Twin Paradox with accelerated Motion
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Undergrad Twin paradox for (accelerated) dummies?
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Undergrad Calculating Spacetime Around Multiple Objects
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Undergrad Anti-symmetric part of an equation
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Undergrad What Is the Proper Time in Curved Space?
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Undergrad Michelson–Morley experiment and the velocity of the ether wind
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Undergrad Create movement from leveraging the propagation of magmatism
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Undergrad Lorentz Contraction & Twin Paradox
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Undergrad Einstein's Derivation of Elapsed Time for Remote Comoving Object
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Undergrad Faster-than-Light Causality-Flip: Thought Experiment Reference?
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Undergrad The Christoffel symbols at the origin -- Why zero?
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Undergrad What is Spacelike vs. Timelike Coordinate?
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Undergrad The invariance of the speed of light is not only a hypothesis?
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Undergrad Twin Paradox with radioactive twins
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Undergrad Relativistic length contraction
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Undergrad Instantaneous coordinates of an event in space (special relativity)
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Undergrad Geodesic in Weak Field Limit: Introducing Einstein's Relativity
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Undergrad Resolving the Twin Paradox: Non-Straight Paths and Proper Time in Space-Time
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Undergrad Understanding Three Force: Definition and Application
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Undergrad Bending of Light Along the Sun: Explaining Half w/ Equivalence Principle
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Undergrad What's the definition of angle in a curved space embedded in a higher Eucledian space?
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Undergrad Newton's Gravity & Lorentz Contraction: Is Modification Needed?
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Undergrad An issue with length contraction
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Undergrad Solving for Extrema of Proper Time Integral
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Undergrad Black hole horizon for different observers
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Undergrad Can Curves Live Out of Embedding Diagrams?
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Undergrad Coordinate and time transformations
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Undergrad Theory Without Spacelike Separations: Can It Exist?
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Undergrad Does light take longer to go a set distance on a train?
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Undergrad Force due to acceleration and time flowing differently
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Undergrad Some thoughts about Bell's string paradox alternatives
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Undergrad Understand 4-Vectors & Spacetime: Hartle Gravity Chapter 5
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Undergrad Beginner's Guide to GR: Questions & Answers
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Undergrad Connection & Affine Geodesics: Q&A
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Undergrad Time difference caused by length contraction
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Undergrad Geometries from Line Element $$dl^2=d\theta^2 + \sin^2\theta\, d\varphi^2$$
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Undergrad Calculation of gravitational redshift in an accelerating elevator
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Undergrad Tipler 1976: Clarifying Symbol Meaning
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Undergrad Can we determine the one way speed of light by combined measurements?
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Undergrad Measuring Time & Spatial Distances: Timelike vs Spacelike
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Undergrad What Would it Look Like to Fall into a Black Hole?
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Undergrad Coordinate System Transformation: Lowering/Raising Indices Explained
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Undergrad When and how can I apply Born rigidity condition?
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Undergrad What is the definition of proper time interval according to Wikipedia?
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Undergrad Trying to understand space-time diagrams
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Undergrad Energy of Light in Accelerating Universe: Comparing Cases
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Undergrad Reconciling Lorentz Four-Force Density w/ Spacelike Four-Current (##c = 1##)
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Undergrad What, exactly, are invariants?
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Undergrad Difference Between Lorentz Transformation & Special Relativity
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Undergrad Hartle, Gravity pg 34: Question about Time in Non-Inertial Frames
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Undergrad Why are acceleration, jerk, etc not relative, just like velocity?
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Undergrad Carroll GR: Geodesic Eq from Var Principles
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Undergrad Using position of free particle to measure time
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Undergrad Equations of Motion for Massless Particle in Potential
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Undergrad Def Proper Time GR: Half or Integral Along Path?
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Undergrad Coord Transform in de Sitter Space: Phys Significance &Linearity?
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Undergrad Richard Feynman: Deriving Lorentz Mass Transformation
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Undergrad Appearance of Warp Bubble Internal Volume to Distant Observer
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Undergrad Carroll GR: Tangent Space & Partial Derivatives
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Undergrad Michelson-Morley: Errors in Calculations?
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Undergrad Wormholes & Warp Drives: Can Circular Polarizers Create Them?
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Undergrad Calculate Contraction 2nd & 4th Indices Riemann Tensor
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Undergrad Matter Gaining Energy from Expanding Spacetime?
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Undergrad Difference Between Locally Flat & Locally Inertial?
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Undergrad Does Special and General Relativity Affect Aging of Apollo Astronauts?
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Undergrad Calculate Gaussian Curvature from 4D Metric Tensor
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Undergrad Cosmic Inflation Explained: Constant Velocity of Electromagnetic Radiation
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Undergrad Spacetime interval and basic properties of light
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Undergrad Understanding Simultaneity Through Male & Female Clocks Meeting
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Undergrad Karl Schwarzschild: Solving GR on the Eastern Front
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Undergrad Effect of Black Hole Spin on Gravity
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Undergrad Spatially Homogeneous Scalar Field on Spacetime: Showing $\nabla^2 f$
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Undergrad Being at the position of a singularity before it is formed
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Undergrad 4D d'Alembert Green's function for linearised metric
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Undergrad Calculating Particle Redshift at Time t_0 & t_1
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Undergrad The Derivative Nature of Time and Its Relation to Earth's Rotation and Speed
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Undergrad Follow Up on M. LeBellac & J.M. Levy-Leblond's "Galilean Electromagnetism
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Undergrad How is proper time visualized in the FLRW metric's 4D spacetime geometry?
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Undergrad Only Minkowski or Galilei from Commutative Velocity Composition
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Undergrad Gravity Wave Speed: Deriving Constancy from Maxwell Eqs.
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Undergrad Understanding Covariant and Partial Derivatives in General Relativity
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Undergrad Lorentz Transformation Derivation: Assumptions Req'd?
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Undergrad What Happens Inside BH Event Horizon?
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Undergrad Calculating Relative Change in Travel Time Due to Spacetime Perturbation
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Undergrad Please help with my spacetime diagrams (relativity problem)
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Undergrad Diagonal Matrix of Stress-Energy Tensor: Why?
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