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.
High School Experimental Confirmation Length Contraction Velocity Addition
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High School Why can't energy or information go faster than light?
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High School General Relativity and the curvature of space: more space or less than flat?
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Undergrad Const Curvature Scalar & 3-Torus: Is It Maximally Symmetric?
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High School Relativistic Photon Mass: Can It Exist?
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Undergrad Explore Alternative Interpretations of Special Relativity
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Undergrad Einstein Field Eqns: East/West Coast Metrics
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Undergrad Understanding Feynman's Relativistic Electric Field Equation
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Undergrad Explaining the Twin Paradox: A Big Problem?
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Undergrad Is it feasible to measure one way speed of light this way?
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Graduate Levi-Civita Connection & Length of Curves in GR
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Undergrad How to Change Between Unit Systems w/ ##c \ne 1, \hbar \ne 1, G \ne 1##
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High School Twin Paradox: Tom & Jerry Agree on Clock Time But Who is Older?
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High School Einstein's Universe (1979) - Nigel Calder, Peter Ustinov
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High School Transform to accelerating coordinates
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Graduate Gravity Theories: GR vs Alternatives - Post 2018
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High School Visualize 2D Intrinsic Curvature of Spacetime (1s+1t) in 3D
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Undergrad Momentum Conservation in Special Relativity: mwu
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Undergrad Inverting the metric coefficients in the Schwarzschild line element
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Undergrad Proper time to reach the singularity of a Schwarschild black hole
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Undergrad Time Dilation & Superluminal Travel: 2 Questions
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Undergrad Why does an object initially at rest begin to fall?
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Undergrad Does Light Curve Spacetime?
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High School Doubt about the relativity of simultaneity
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Undergrad Interpreting Schwarzschild Metric: Photon Falls Toward Black Hole
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Undergrad Charged Particle Free Fall in Grav Field: Does Anyone Know Answer?
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High School Why and how does the frequency of a moving clock affect its ticking speed?
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Graduate Find 2D Geometry of Line Element in Coordinates
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High School Where Does Momentum Go Near Merging Black Holes?
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Insights Does the Block Universe of Physics Mean Time is an Illusion?
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Graduate Covering Group of SO(g) & Understanding Spinors on Curved Spacetime
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High School Lagrangian Point in General Relativity
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High School Looking Out of the Window: Phys & Math Meaning in Postulates & Principles
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High School Shape of Hubble sphere at relativistic velocity
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High School Can someone please explain Feynman's index notation?
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High School Are time and light at the same speed?
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Undergrad Video camera in a moving rocket
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Graduate Block Universe Theory: Implications & Multiverse
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Undergrad Gravitons Replacing General Relativity: Can it Work?
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High School Do we feel the Earth going around the Sun as acceleration?
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Graduate Determining Geometry of Line Element: A General Method?
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High School Light Behaviour at High Speed: Explained
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High School Paradox about black hole evaporation
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Undergrad Is it possible to extend Newtonian gravity to include energy as well as mass?
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Graduate Black Holes & White Holes: Same or Different?
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Undergrad Temporal Gradients at Event Horizons of Black Holes
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Undergrad Electrodynamics of Dielectrics: 4D to 3D
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High School Bob & Ted See Different Ages for Alice on Earth
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Undergrad The Speed of Light: Can it Travel in Opposite Directions?
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Undergrad EM Field Strength in Curved Spacetime: Is it Unchanged?
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High School Why is the speed of light constant?
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Undergrad The center of mass & relativistic collisions
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Undergrad Q re de Sitter–Schwarzschild metric
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Undergrad How Does Relativity of Simultaneity Clash w/Thermodynamics?
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Undergrad Special Relativity: Intuition & Quantities Explained
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Undergrad Check for geodesically-followed path in a coordinate-free way
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Undergrad Logic question on relativity- no math
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Undergrad Riemann Tensor, Stoke's Theorem & Winding Number
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High School Understanding Strong Equivalence Principle Errors & Misunderstandings
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Undergrad Finite Lorentz Transformation via Poisson Bracket
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Undergrad Special Relativity & Non-Instantaneous Force Equations
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Graduate Axisymmetric vs Spherical Metric Comparison
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High School Particle Horizon & Coformal Time Near c - Observer Effects
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Undergrad Gravity transition directly at the underside of a "shell planet"
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Undergrad Another spacetime visualization
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Undergrad Variation of Ricci scalar wrt derivative of metric
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Undergrad Acceleration in Special Relativity
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High School Twin paradox explained for laymen
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High School Black hole horizon and Hawking evaporation
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Graduate Parallel plate capacitor in the Rindler metric
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Undergrad Can Newtonian Gravity be Thought of as a Theory of Curved Time?
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Undergrad Geodesics using 2 Variables: Time & Radius from Mass
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Undergrad Speed of light for a Rindler observer
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High School Special Cases of Stress-Energy Tensor in GR
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Undergrad Do you accelerate through time when you stand still on Earth?
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High School Shankar on Lorentz Transformation: Does x' = ct'?
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Undergrad What initiates gravitational movement?
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Undergrad Mercury Perihelion Precession: Analytic Derivation
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Undergrad Deriving vacuum FRW equations directly from action
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Graduate GR: Is Schwarzschild Spacetime Time-Independent?
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Undergrad Would light keep on a straight path after it bends?
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High School Kugelblitz at the speed of light misconception
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Undergrad General Generator of Lorentz Transformation in Hamiltonian Formalism
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Undergrad Gravitational waves as not "proximal"?
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High School On time dilation and length contraction
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Graduate Energy condition respecting warp drives in Einstein Cartan theory
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Undergrad Rotation or acceleration defined without relation to something else
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Undergrad Length Contraction & Time Dilation: Proving It
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High School Frame Dragging Rate: Mass Proportionality?
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Graduate Explore Carroll's Theory on Dual Space and Real Numbers
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High School Near the speed of light time slows down but not at everyday speeds?
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Undergrad Connection coefficient transformation law
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Graduate Alternative theories to General Relativity
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Undergrad Space Travel: Possibilities & Questions
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Graduate Is time real (in a physical sense)?
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High School Is the gamma-factor for Tachyons real?
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Undergrad The Energy - Momentum Equation vs the Energy - Mass Equation
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Undergrad Special Relativity and Velocity
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Undergrad Particle Perspective: How Relativity Affects Us
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High School Just a question about the tangent basis
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