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 Measuring Fictitious Forces in a Closed Box
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Undergrad Spacetime and Events in (x,y,z,t)
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High School Inertial & Gravitational Mass: When Do They Differ?
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Undergrad Electromagnetic Fields and the manipulation of Space-Time
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Undergrad Question about an entanglement paper
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Undergrad How Do Rockets Traveling at High Speeds Observe Each Other's Velocity?
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Undergrad The velocity of a moving frame of reference
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Undergrad Alternative form of geodesic equation for calculating Christoffels
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Undergrad Is it possible to have synchronized clocks in a rotating system?
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High School Can I keep multiple clocks in sync after a ride on a roller coaster?
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Undergrad Question regarding the nature of mass inside a black hole
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High School Rest Energy and a 1 million solar mass black hole
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Undergrad Can an object fall into a black hole at faster that the speed of light?
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Undergrad Radius in Schwarzschild Metric: Definition Explained
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Undergrad Do clocks on Bell’s spaceships stay synchronized?
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Undergrad Tensor Field Notation: Einstein Gravity Explained
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Undergrad Space-Like Hypersurface: Simultaneous Events?
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High School Does my speedy spaceship (.999+C) have a temperature?
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Undergrad Special Relativity: Train in Tunnel Paradox Solved
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High School Can Canceling Orbital Motion Improve Rocket Efficiency?
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Undergrad Covariant derivative of the contracted energy-momentum tensor of a particle
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Graduate Do Moving Masses Slow Down Due to Gravitational Waves?
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High School Train platform -- light speed and time quandry
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Undergrad Is there a solution for the behavioural contradiction in RT?
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Undergrad Measuring Mass of a Bowling Ball Dropped into a Black Hole
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High School Planck Length: Upper Limit on Photon Frequency & Momentum
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Insights Can I Send a Signal Faster than Light by Pushing a Rigid Rod? - Comments
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Undergrad Derivation of Geodesics Eq from EM Tensor of Point Particle
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Undergrad Issue With Derivation of Gravitational Time Dilation
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Undergrad Gravitational Potential Energy in GR
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High School Prereqs for Posting in Special & General Relativity
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Insights Understanding Precession in Special and General Relativity
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High School Why is time orthogonal to space?
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Graduate Thermal State in Relativity Theory: Can It Happen?
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Undergrad Accelerated Triangle and Length Contraction
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High School Effects on time by gravity or motion
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Graduate Forgetting Non-GR Physics: How Specialists Can Stay Sharp
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Undergrad Stress-Energy Tensor: Specified or Calculated?
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High School Is this an adequate thought experiment?
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Undergrad Modifying EFE to Match Newton's Gravity Predictions
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Undergrad Measuring Gravity Wave Time Distortion Accuracy
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Undergrad What is the Strange Solution to the EFE with a Born Frame and Rotating System?
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Undergrad Simultaneity of two light rays in different reference frames
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High School Can we produce black holes by particle accelerators?
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High School Twins Paradox: Dropping a Ball from a Moving Train
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High School Einstein's train and simultaneity
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Undergrad How Do Physical Quantities Relate to Spacetime in Einstein's Field Equations?
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High School Why do things in free fall accelerate?
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Undergrad Boosting to an instantaneous rest frame
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Undergrad Newton vs Einstein: Explaining Other Forces
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Graduate Index Juggling: Angular Momentum Tensor & Inertia Tensor in 3D-Space
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Undergrad Can empty space be considered ‘elastic’ and expandable?
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High School Bell's Spaceship Paradox & Length Contraction
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Graduate Significance of "Change of Signature" in Classical Relativity
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High School Gravitational Effect from Relativistic Mass: Answers & Questions
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Graduate Model Near-Colliding Ultra-Relativistic BHs w/ Colliding PP Waves
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Graduate Solving Møller Energy Distribution Problem in Paper
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Undergrad Gravitational potential gradient in accelerated reference frames?
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High School Bohr's Views on Relativity: What Did He Think?
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Undergrad Is there such a phenomenon as "micro-frame drag"
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Graduate Electromagnetic Stress Energy Tensor Formula (-,+,+,+)
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High School Event Horizon: Understanding the Singularity of a Black Hole
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Undergrad Orthonormal Basis - Definition & Examples
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High School Polarized Electron in a Rotating Reference Frame
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High School Spacetime interval - alternative view - maybe?
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High School Deriving the Lorentz transformations
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Undergrad Invariant Mass in Gravitational Fields: Special Relativity
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Undergrad Are Dimensions Truly Relative to the Observer in the Coastline Paradox?
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Undergrad Length Contraction: Measuring a Difference of 55 Nanometers
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Graduate A couple of interesting black hole papers
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Undergrad Does Curving Space by an Approaching Mass Do Work?
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Graduate Understanding Stokes Theorem and is the variation of the metric a tensor?
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Undergrad Can all fundamental constants be set to 1 in natural unit systems?
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Graduate SR Foundations: Parallax Methods? - Reference Request
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Insights Defining Large-Scale Isotropy: A Formal Definition
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High School Relativator: The circular slide-rule for physicists
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Graduate Relativity Visualization: Aging Twin Paradox - Adam Toons
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Graduate Correcting a Typo in d'Inverno's Lagrangian on Page 172 | Section 11.3 Results
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Graduate Rotating black hole interiors take 2
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Graduate Price's Power Law: Mass-Energy Dampening & h Constant
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Graduate Vanishing twist of time - like killing field
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Graduate EP and active/passive mass
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High School Should the 'time' axis of a Minkowski diagram be time's imaginary unit?
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Undergrad What is ds in ds2 = dx2 - cdt2
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High School Trying to understand Lorentz Transformations
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Graduate Light interferometry as described in Thorne's black holes and time warps ?
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Undergrad Black Holes: Time Bidirectional?
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High School Implications of FTL signals in SR
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Undergrad Fixing Rindler Coordinates when a=0
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Undergrad Is a photon simply a vibration of the spacetime lattice?
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High School Does Time Exist Without Motion?
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Graduate Coord Transf. in Linearized GR: Understanding Metric Transformation
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Graduate Einstein-Hilbert Action -> GR is a saddle point?
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High School Understanding Final Form of Lorentz Transformations
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Graduate Restframe of Photon: Explained
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Graduate Question about "Rest frame of a photon" FAQ
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Graduate Curved-spacetime, but why curved coordinates?
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Graduate Gaussian to MKS Four-vector Conversion
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Graduate Is the Schwarzschild spacetime with negative mass geodesically complete?
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High School Is Time Relative? Understanding Special Relativity
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