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 What (if anything) limits the speed of something falling into a black hole?
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High School Relativistic Mass of Sub-Atomic Particles: What Does it Mean?
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Undergrad Maxwell's Equations, Hodge Operators & Tensor Analysis
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Undergrad Einstein Field Eqs: Stress Energy Tensor Explained
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High School Can General Relativity and Quantum Field Theory Be Reconciled?
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Undergrad Finding distance in polar coordinates with metric tensor
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Undergrad Speed of gravity vs. speed of light
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Undergrad Relativistic Mass Calculation with 4th Dimensional Vector
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Undergrad Contradiction between two fundamentals
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Undergrad Torsion & Non-Closed Rectangle in Feynman & Penrose
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Undergrad Spinning disk, length contraction, & equivalence principle
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Undergrad Theorem Proved: Universal Speed C in SR?
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Graduate Can Weyl Tensor Look Like Negative Mass?
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High School Speed of light and modern physics
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Undergrad How do I apply weak field approximation to the Einstein field equation?
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Undergrad Why must the spacetime we inhabit be a geodesically complete manifold?
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High School According to General Relativity, would the Earth be 'flat'?
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Undergrad GR in Newtonian Limit: Understanding Weak Fields & Inequalities
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High School Is Light Traveling Through Time?
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High School Time Dilation: Moving Rocket 0.5c vs Accelerating Rocket 0.5c
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Undergrad Where Did LIGO Find Merging Black Holes?
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Undergrad Gravitational Wave Modeling: A Thought Experiment
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Undergrad Understanding the Proof of Delta Variation for Determinant of Metric
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Undergrad Einstein Hilbert action
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High School Volumes and Hyper Volumes Related Special Relativity
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Undergrad Gradient in the rate of time vs acceleration
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Graduate Taylor Expansion of Metric Tensor: Troubles & Logic
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Undergrad How do you calculate the time component of a 4-Vector
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High School Gravitational waves and "warp drive"
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Undergrad EM Force vs. Gravity: Modeling Spatio-Temporal Curvature
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High School How is light influenced really close to the event horizon?
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Graduate Calculating Ricci tensor in AdS space
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High School Is Einstein's explanation of gravity just a geometrical replacement?
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High School Transforming Relativistic Kinetic Energy: A Concise Mathematical Trick
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Undergrad Schwarzschild equation of motion: initial conditions
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High School Faraday's disk and "absolute" magnetic fields
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High School Einstein Proven Right by 2017 Eclipse? Investigation
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Undergrad Shape of Vacuum Space: Constant Spatial Volume with Time
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Undergrad LIGO and light speed constancy
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High School Do Gravitational Waves Always Travel at the Speed of Light?
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Graduate Does the inverse square law hold indefinitely for gravity?
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Undergrad Are Local Lorentz Transformations Possible with Varying ##\vec{x}##?
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Undergrad Are Electric and Gravitational Fields Different for Moving Objects?
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Undergrad Speed of light on a moving platform
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High School Relative Rotation: Physics Approach for Newton's Bucket in Empty Universe
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Undergrad Stress Energy Tensor: How Does It Implicate Flow of Energy?
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High School Postulates of General Relativity
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Undergrad Can two gravitational waves orbit each other?
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Undergrad Positive Charge Magnetic Fields: Real World Examples
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Graduate Black Hole Merger: Analytical or Numerical Solutions?
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Undergrad Velocity Addition Formula: u_y > c?
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Undergrad Unexpected result on Lorentz transformation
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Undergrad Understanding Stress Energy Tensor of Fluids
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Undergrad Index Gymnastics: Matrix Representations & Rank-2 Tensor Components
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Undergrad Does Feynman's Work on Gravitons Clarify Quantum Gravity?
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Graduate Derive the Bianchi identities from a variational principle?
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High School What happens when you solve for c?
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High School Concept of the stability of the speed of light
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High School Can Relativity Theories Actually Permit Faster-Than-Light Travel?
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Undergrad Pressure term in the energy stress tensor
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High School Newb question about relativistic mass
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Undergrad How does Einstein define simultaneity in his 1905 paper?
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Undergrad Comparing Vacuum Solutions to Topologies of Einstein Space
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Graduate How Does Physics Behave in 2+2 Dimensional Spacetimes?
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Undergrad Is Gravity Invariant During Motion?
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High School Electric+Magnetic Force Between a & b Charges: Inertial Frames
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Undergrad Twin paradox in SR and its applicability to radioactive decay
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High School Center of momentum and mass energy equivalence
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Undergrad Proper time to reach the singularity - rocket acceleration
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Undergrad How does this not get me traveling to another star FTL?
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High School Understanding Mass and Density in Relativity Theory: A Critical Analysis
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High School Could this FTL idea with a fast moving large mass be possibl
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Undergrad Photon states should not evolve?
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Undergrad How can information possibly be created?
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Undergrad How much would time pass between watching the sun set ....?
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High School The "why" behind time dilation
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High School How does time behave in overlapping gravitational fields?
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Undergrad Time in QFT vs. QM: Exploring Differences in Treatment
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High School Can Light Speed Travel Change Our Perception of Time at Proxima Centauri?
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Undergrad Gravitational time dilation in Weinberg's "Cosmology"
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High School Solving Mysterious Relativity Paradox: New Derivation of E=mc^2
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Undergrad Non-radial geodesics in Schwarzschild spacetime
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Undergrad My conclusions regarding "the laws of nature"
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High School Einstein's theory of relativity and time travel
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Graduate What is the significance of the nonholonomity condition in General Relativity?
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Undergrad Domain of Applicability of Post-Newtonian Formalism
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Graduate Unstable 5D Theories: The Search for Stable Black Holes in Higher Dimensions
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Graduate Corollaries of Lorentz Invariance: Overview & Explanation
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High School Is there any proof that gravity is an attractive force?
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Undergrad Why do people keep saying photons are timeless?
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Undergrad Force on an Object according to the General theory of relativity
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Undergrad Could Gravity Ever Be Negative?
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High School Does gravitational time dilation cause gravity's attraction?
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High School Does Gravity Have the Power to Slow Down Light?
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Undergrad Relativistic Aberration: Intuitive Understanding
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High School Minkowski metric, scalar product, why the minus sign?
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Undergrad Derivation of geodesic equation from the action - quick question
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High School Newton's law under Lorentz transformation
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Undergrad Mechanical clocks and time dilation
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Undergrad Is the Massless Photon Explanation for E=mc2 Valid?
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