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 What Is the Radius of Curvature of Space on Earth's Surface Due to Its Mass?
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Undergrad What Experiments Demonstrate Time Dilation?
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High School What if we use a non physical reference point to measure an object's mass?
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High School Speed vs. time for our Galaxy and an Observer
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Graduate Quantum mechanics and frame dragging
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Undergrad Fermi-Walker transport of proper acceleration along timelike congruence
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Undergrad Mother of all equations for the Lorentz force
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Undergrad Properties of Born rigid congruence
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Undergrad Muon travel distance vs Atmosphere Thickness?
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High School Which term of the Einstein equation is larger?
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Undergrad Can there be a maximum curvature of spacetime?
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Graduate Does deceleration cause linear frame dragging?
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Undergrad For a relativistic spaceship, what is the most recent news the ship gets from Earth?
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Graduate Where Can I Find Detailed Derivation of Teleparallel Gravity Field Equations?
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Undergrad Bell's Spaceship Paradox, Born Rigidity, and the 1-Way Speed of Light
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Undergrad Is there a gravitational effect on spatial measurements
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Undergrad How can the volume of a star be determined?
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Graduate On the order of indices of the Christoffel symbol of the 1st kind
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Undergrad Deriving e=mc^2, how is it possible?
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High School In GR gravity, does "equal and opposite" still hold and what does that mean?
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Undergrad I want a good reference to a discussion of the meaning of "the speed of light is constant"
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Undergrad Potential Energy in a Stretched String in SR
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Undergrad Correct Description of Black Hole Interior
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High School Is crossing a black hole's event horizon possible?
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Undergrad How Does Mass Influence Spacetime Curvature?
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High School How fast are gravitational forces transmitted?
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Undergrad GPS system and general relativity
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High School Why do people care about vacuum solutions in GR?
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Undergrad One-Way Speed of Light: Is it Possible?
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Undergrad Question about Two Clocks in this Relativity scenario
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High School A question about quarks and black holes
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High School Questions about space and matter
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Undergrad Why does general relativity break down at high energies?
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Graduate Can an imminent laser strike ever be observable?
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Undergrad Bell's spaceship paradox unknown? Interpretation?
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High School Does Relativity Impact Gravity's Influence on Fast-Moving Objects?
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Undergrad Why Is the Invariant Interval True for All Values of s?
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Undergrad Twin Paradox - difference between outbound and inbound
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Undergrad I have a question about gravity -- If the value of the energy momentum tensor (Tμν) becomes zero, can it become gravitational-free?
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Undergrad What if particles are moving near light speed and one slows?
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Undergrad Does Phantom Dark Energy Violate Conservation of Energy?
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High School What Are Gravitational Waves?
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Graduate Parallel Transport and Geodesics
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Undergrad Understanding the phrase "simultaneity convention"
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Undergrad EM Faraday tensor transformation for conductor carrying current
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High School E-field of a constant velocity charged particle
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Undergrad Experimental evidence of the existence of an event horizon
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Undergrad Can “speed of light” distinguish all Timelapse videos from real motion?
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Undergrad Spacetime coordinate smoothness requirement
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Undergrad Gallilean v/s Lorentz transformation
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Undergrad Did the Michelson-Morley Experiment Disprove the Ether Theory?
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Undergrad Gravitational wave propagation in GR
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Undergrad Information transfer between moving bodies - sped up or slowed down?
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Graduate Dirac "GTR" Eq. 27.11 -- how to show that a boundary term vanishes?
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Undergrad Does expanding space cause cosmological redshift?
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Undergrad What if one is in 1905 and debating foundational fundamentals?
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Undergrad Couple questions about time re-scaling function in Birkhoff’s theorem
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High School Formation of a black hole using acceleration
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Undergrad Proving speed of light constant “c” is the same in all directions?
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Graduate Proof of covariant derivative of spinor
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Undergrad Intra-Universe Wormhole Metrics
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Undergrad General Relativity and the precession of the perihelion of Mercury
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Undergrad Does gravity bend gravitational waves?
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Undergrad When time is not orthogonal to phi, that means there is a preferred direction in space? How?
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Undergrad Basic Special Relativity question but the math isn’t working
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Undergrad Are gravitons necessary?
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Graduate Proving that Levi-Civita tensor density is invariant
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Undergrad Can you indeed rescue a person from a Black Hole?
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Graduate Relativity: Test charge moving perpendicular to a current carrying wire exhibits a force
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High School How to intuitively understand the formula S² = x² - c²t²
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Undergrad Why isn't TT gauge over constrained?
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Undergrad Minkowski to Euclidean line element from coordinate changes?
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Graduate Diffeo-invariant action for a matter covector field
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Undergrad Final part of proof of timelike Killing w/ Frobenius --> static
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Undergrad Einstein field equations
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Undergrad Online Christoffel Symbols Calculator
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High School Question about bendability of objects in 4 dimensions
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Undergrad A question about Relativity of Time using Time dilation experiment
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Undergrad On the existence of Gravitational energy in General relativity
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Undergrad Null energy condition constrains the metric
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Undergrad SR flat Lorentzian manifold and Anderson simultaneity convention
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Undergrad The generators of a ``Poincare-type'' group in momentum space
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Undergrad Understanding Spacetime simultaneity in twin paradox scenarios
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Undergrad Construct a Diagram that Illustrates The Galilean Law of Addition of Velocities
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Undergrad Standing light waves if the one-way speed of light were not constant?
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Undergrad Evaporating black hole: First principles consideration
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High School Falling into a black hole
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Undergrad Pullback & orthogonal projector
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Undergrad Unruh Radiation and Black Holes
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High School Is velocity the reason for the time dilation effect?
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Undergrad What Would the Universe Look Like as a Manifold with Boundary?
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Undergrad How to get metric field using a path dependent parallel propagator
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Undergrad What are Killing vectors?
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Undergrad Is this a Killing vector field?
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Undergrad Which theory of time is the most evidence-based?
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High School Implications of negative Michelson-Morley result
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Graduate Variation of CMFR mass density ##\rho## along a world line
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Undergrad Time dilation from galactic gravitational mass
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High School Detection of red-shifted photons near an event horizon
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Undergrad Is time dilation a real effect?
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