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 Universal Block Theory: Free Will
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High School Proving Special Relativity w/ Standard Equipment
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High School Confused about time dilation and cosmic speed limit
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Graduate Sign of Curvature in Flamm's Paraboloid: Negative?
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High School One way speed of light in one reference frame measurement
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Graduate Question on Equation in Zee's Gravity in a Nutshell P107
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High School Finding One-Way Speed of Light: Use One Clock
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Undergrad Could Tachyons Discredit Relativity?
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High School Black Holes: Can Anything Reduce Their Size?
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Undergrad Lorentz Invariance of Q in Weinberg: Justifying Transformation
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Graduate Unruh & Minkowski Modes: Analytic Extension Explained
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Undergrad Gravity: Force or Acceleration?
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Graduate Is gravity simply an interaction in the gauge theory of gravity?
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Graduate Prove Fermi-Walker Transport of Gyroscope's Spin Vector w/No Applied Moment
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Undergrad Normalization Constant in Einstein-Hilbert Action
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Undergrad Falling into a Black Hole: Blueshift Questions Explored
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High School FAQs about Bobrick & Martire's Warp Drive & Lentz's Paper
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Undergrad Do Fictitious Forces Still Matter in General Relativity?
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Undergrad Linearized Gravity & Metric Perturbation when Indices Raised
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Undergrad Variation of Four-Velocity Vector w/ Respect to Metric Tensor
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Graduate Merger of Extremal BHs Causes Naked Singularity?
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Graduate Tony Rothman Questions E=mc^2 in American Scientist
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High School Paradox in the block universe interpretation
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High School Time Dilation: How Does Speed Affect Aging?
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High School I have a few questions about Warp drives? I am a layman.
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High School Understanding Entangled Particles in Different Time Frames
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Undergrad Black hole inside of a black hole.... can it be done?
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Undergrad Clarification on Rindler coordinates definition
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Undergrad The Universe filled with a "homogeneous perfect fluid"
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High School Do black holes determine time's arrow?
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Undergrad A problem with the solution to the ladder paradox
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High School Basic introduction to gravitation as curved spacetime
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Undergrad Is the sign of the Einstein equation right in Chandrasekhar's Black holes?
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High School Can we see matter crossing the Event Horizon with a powerful telescope?
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Undergrad Assumption in the derivation of the Lorentz transformation
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High School Gravitons: Relationship to Space-Time & Black Holes
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High School Is length contraction (Lorentz transformation) an illusion or real?
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Undergrad Understanding Jacobian Matrix Transformation in Special Relativity
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Undergrad Definition of Rindler Horizon: A Global View
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Undergrad Absolute meaning of spatial deviaton angle of light around the sun
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Graduate Rindler Horizon Subtleties: Advanced Discussion
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Undergrad Bondi ##k##-factor concept from first principles
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High School Equivalence Principle and Rindler Horizons
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Insights Geodesic Congruences in FRW, Schwarzschild and Kerr Spacetimes
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High School Free fall floating in a closed spaceship near a gravity source
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High School Distance Length Contraction at Light Speed
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Undergrad Observer Inside Collapsing Shell
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Undergrad Reference Frame, Difference in Kinetic Energy, Fuel Consumed
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High School Why does it require an infinite amount of energy to reach the speed of light?
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High School Is there an inside to a Black Hole?
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Undergrad Is acceleration absolute or relative - follow up
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Undergrad Reference frame vs coordinate chart
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Undergrad Uncover Traps in Spacetime Diagrams: Bob & Alice's Cases
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Undergrad Request for Input: 2D Minkowski Spacetime Diagram Generator
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Graduate Radial Excess Calc: GR, 4πGρ & R00
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Undergrad Time Dilation on 3D Torus: Clock Speed & Why It Matters
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Undergrad Detecting Gravitational Waves w/ Interferometers: Explained
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Insights Relativity using the Bondi k-Calculus - Comments
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Undergrad Gravitational Field of Electromagnetic Waves: How is it Generated?
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Insights Relativity Variables: Velocity, Doppler-Bondi k, and Rapidity - Comments
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Undergrad A computation of an integral on page 344 of Schutz's textbook
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Undergrad Hafele-Keating Exp: Balancing SR Effects in Plane Ref Frame
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High School How does curvature of spacetime affect the motion of test particles?
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Undergrad Merging black holes: gravitational waves and information
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Undergrad Angle-Preserving Linear Transformations in 2D Space for Relativity
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Graduate Understanding Frame Fields in GR: A Beginner's Guide
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Undergrad Time Dilation: Gravitational & Velocity Effects Explained
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Graduate Orbiting spaceship just above a black hole horizon
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Undergrad Conservation of momentum in a collision
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Undergrad Kinetic vs Gravitational Time Dilation: Perceived Speed
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High School L = 0 in the equation for effective potential energy?
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High School Can't Avoid Invoking Preferred Frame: A Look at Free Falling Into a Black Hole
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Undergrad Solving Spinorial Maxwell's Equations with Wald
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Undergrad Synchronous Reference Frame: Definition and Usage
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Undergrad Black hole formation watched from a distance
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Undergrad Proving Lorentz Metric on Real Type (1,0;1,0) Tensors in Wald Ch. 13
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Undergrad Cartan's Understanding of Einstein Field Equation
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Undergrad Kerr Black Hole: Superradiance Flux - Show Negative when 0<ω<mΩH
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Undergrad E Vector in E=mc2? Scalar Multiplication & Vectors
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Undergrad Relativistic Force & Velocity Relation to Acceleration
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High School Time Dilation in a Galaxy: Calculating Mass Effects
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Undergrad Does Time Drive Black Hole Travelers to a Central Singularity?
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Undergrad How Long Does it Take to Fall into a Black Hole?
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Undergrad GW detectors -- How much has their sensitivity improved since 2008?
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High School Understanding Spacetime Diagrams from "Reality is not What it Seems
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Undergrad Principle of relativity for proper accelerating frame of reference
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Undergrad Shape of de Sitter Universe: Is Hyperboloid Misleading?
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Undergrad Time travel is a fact or fiction.?
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High School Charged Particle on Earth's Surface: Will It Emit Radiation?
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Undergrad Does time dilation occur due to the speed limit of light or c?
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Undergrad Understanding Frequency in Rindler Coordinates for a Scalar Massless Field
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High School Twin Paradox: Orbital Geodesics, Gravity, & Time Dilation
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Undergrad Future null infinity confusion
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Undergrad Distinguishing Einstein Cartan from GR: Experiments
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High School Time Dilation: Traveling to a Distant Star in 4.5yr
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Undergrad Rindler Transformation & 't Hooft's Introduction to General Relativity
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High School Space-Time Expansion: Objects Accelerating Without Force?
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High School How Matter Bends Space & Slows Time: Physical Mechanism
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Undergrad Natural direction of pushforwards and pullbacks
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Graduate Condition for a spacelike surface to be achronal
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