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 How Can I Design an Experiment to Ensure Simultaneous Light Arrival?
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Undergrad A Hidden Zero in Einstein's Simple Derivation
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Undergrad Observation of the effect of gravity on the motion of antimatter
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Undergrad The Mirror Paradox: Exploring Special Relativity Theory
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Undergrad Why are Kruskal coordinates related to a freely falling observer?
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Undergrad I think the special theory of relativity self-contradicts
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Undergrad Ricci Scalar For Astronomical Body
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High School Thought experiment: The twin paradox, observed from far away
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Undergrad Is Simultaneity Absolute or Relative in the Theory of Relativity?
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High School How fast do space-time changes propagate?
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Undergrad Eddington-Finkelstein coordinates for Schwarzschild metric
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Graduate Galactic Rotation and Energy-Momentum Tensor
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Undergrad Physical meaning of null spacetime interval
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High School Creating Metric Describing Large Disk
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High School Can Dark Flow Be measured, based on Special Relativity?
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Graduate How is eq. 1.5.3 written using three-vectors and how does it lead to eq. 1.5.4?
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Undergrad How do you differentiate between the inner and lower indices on a Lambda tensor?
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Undergrad Spacetime distance and ruler-measured length on an XT chart
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Undergrad A question about static spacetime in GR
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Undergrad A question about geodesics and notion of parallelism
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Undergrad What is the proper time of a vertically moving inertial clock?
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Undergrad How can a square-based lattice turn into a circular-based one?
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Undergrad Is an accelerating frame the same as an inertial frame at a point?
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High School How to measure time in reference frame with clock?
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Undergrad Obtaining the matter Lagrangian from the stress energy tensor
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High School Further Understanding Simultaneity Conventions
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Graduate General equation for hyperbolic motion in a 2D plane -- Help needed please
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Undergrad What are the effects on a stationary observer for Kerr metric?
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Undergrad Action of metric tensor on Levi-Civita symbol
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Undergrad Covariant divergence of vector; physical meaning with contracted Tuv
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High School Video: Mathologer on visual logarithms (and hyperbolic trig)
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Undergrad Are photons definitely massless?
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High School Another special relativity related "paradox"
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High School Is there a lining to our Universe?
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Undergrad Help Understanding Equation 3.6 in Covariant Physics by Moataz H. Emam
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Undergrad What is the Connection Between Black Holes and the Big Bang?
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Undergrad Inverse Square Law for Black Holes
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Undergrad Can you increase the mass of a closed system with information?
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High School What is the distinction between the Weak and Strong Equivalence Principles?
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Undergrad Asymmetry in Length contraction?
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High School Is Time Defined by Relative Motion in SR and GR?
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Undergrad Special Relativity Paradox "Terrorist and Spaceship"
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Undergrad Car, wheels and Lorentz contraction of the road: Is this a Paradox?
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Undergrad Invariant Mass-Energy in FRW Spacetime
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Undergrad Galilean relativity in terms of homogeneity
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Undergrad What was the four-momentum meant to include?
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Undergrad Noether's second theorem: two questions
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Undergrad Condition for Centering Starlight in a Water-Filled Telescope?
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Undergrad Did Born Rigidity Lead Einstein to Conclude Spacetime is Curved?
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Undergrad Quasi-local mass as a measure of the gravitational energy?
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High School Trying to understand what "time" is (layperson)
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Undergrad Lorentz Transformation: Premises + Derivation
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Undergrad Coulomb’s Law in a Moving Reference Frame
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Measuring Time Dilation from 25Kg Lead Brick w/3 Cesium Oscillators
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Undergrad Covariant Derivative Rank 2 Contravariant Tensor
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High School What is the Experimental Basis of Special Relativity?
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Undergrad Observer on Earth watching a spaceship traveling at c/2
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High School How to compare the proper times of two spatially distant mass points?
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High School What is the effect of the twin paradoxon?
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High School A scenario to help understand the twin paradox in SR
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High School Why does length contraction occur and how does it relate to time dilation?
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Undergrad Three inertial particles: Separating the twins from the paradox
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Undergrad Yet another spacetime-bending layman question
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Graduate What's the relationship between RMS framework and the Lorentz group?
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Graduate Papapetrou transformation: Conditions to be satisfied to achieve transformation
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High School Max Speed of Molecules: 1 Electron Stripped?
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Undergrad Does the past of an observer still actually exist in their "now"?
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High School Time dilation in a planet-moon system
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High School Are planetary orbits elliptical because of a space–time conic section?
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Undergrad Forces and gravitational time dilation
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Undergrad How to derive irreducible representations/tensors?
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High School Measuring Speed of Light: Transit Time & Interference
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High School Length Contraction: Apple Hanging from Tree & Earth
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Undergrad How does an observer moving at relativistic speeds perceive a pulsar?
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High School Transfer speeds of forces affected by time dilation?
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Undergrad Is There an Atomic Clock Experiment on the Moon Testing Relativity?
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High School The expansion of the Universe and time travel (By a non-scientist)
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High School What does 3-dimensional space deform into, in the presence of gravity?
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Undergrad Relevant/irrelevant clocks for experimental tests of relativity
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High School Photons on a perpendicular bisector path from a black hole's core
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Undergrad Atomic Clock Speed graph between two stationary masses
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Undergrad Event Horizon movie, with some interesting concepts (papers cited)
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Undergrad Any advancements in the feasibility of Alcubierre warp drive science?
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High School Detecting cosmological redshift in an empty part of the Universe
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Undergrad Stress-energy tensor and energy/momentum conservation clarification
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High School Define a vector that transfers the reference systems to the future
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Undergrad Why is there nothing faster than light?
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Undergrad Constancy of Speed of Light: Postulate or Assumption?
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Undergrad Radiatively efficient accretion onto BHs
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Undergrad Time Measurement in Extremely Curved Space Regions
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Graduate Preserving Covariant Derivatives of Null Vectors Under Variation
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High School Does the fact that gravity moves at the speed of light affect how planets move?
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Graduate Continuation of Coordinates Across Black Hole Horizons
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Undergrad Mass Density of Photons in Refractive Medium
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Undergrad Taylor Expansion of Metric Transformation in RNCs
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High School Sun's Mass Loss: 4 Billion kg/sec from Sunlight & Ejected Particles
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Undergrad Compatibility of Classical Electromagnetism & Relativity
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High School Can Relativistic Mass Create a Black Hole?
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High School Pound & Rebka Experiment: Earth's Spin Rotation Speed
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Undergrad 3 clocks thought experiment - Absolute vs. relative aspects?
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