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.
Graduate Can We Flatten Space with York Decomposition?
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High School Question about the Entropy of a Black Hole Singularity
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High School But how does something start moving?
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High School Events vs Effect of Events in Relativity of Simultaneity
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Undergrad Speed of light one more time
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Undergrad Principal and Gaussian curvature of the FRW metric
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High School How does Einstein's equation work? Why do we need to square c?
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Insights Addition of Velocities (Velocity Composition) in Special Relativity
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Undergrad Physical Difference Between Co- and Contravariant Vectors
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High School Let me ask a thing about the Speed of Light
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Undergrad Co- and Contravariance
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Undergrad Determining a stationary point of reference to base all absolute motion
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High School Crossing the Bekenstein Bound at Black Hole Event Horizon
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Undergrad Relativity and a Mirror
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Undergrad Validity of Birkhoff's theorem in flat Minkowski spacetime
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High School Challenging the notion of "crossing" a black hole's event horizon
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Undergrad Follow-up on Index notation for inverse Lorentz transform
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Undergrad Canonical energy momentum tensor: Quick question
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Undergrad Embedding Diagram of Weyl Metric in ##R^3##
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Undergrad Higgs Field & GR: Are They Related or Not?
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High School Calculating Time taken to reach speed with Time Dilation
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Undergrad How does an arbitrary choice of the origin affect real observations?
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Undergrad Asteroid hits static black hole
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Graduate Overall perturbation for two free-falling particles in flat spacetime
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Undergrad Does everything move at the speed of light?
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High School What is the relationship between speed and time dilation in special relativity?
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Undergrad How Can Tensors Be Evaluated to Scalars?
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High School Pole-barn paradox, one question
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High School Is Time Travel Possible Near Black Holes?
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High School What Are Closed Timelike Curves and Common Misunderstandings About Them?
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High School What is the essence of the ladder paradox in relativity?
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Undergrad Researchers calculate how much faster time passes on the Moon
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High School How far away can a World So Newly Born Be at relativistic velocities?
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High School Speed of light seen by a moving observer
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Graduate Show Lagrangian is invariant under a Lorentz transformation without using generators
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Graduate Kerr to Schwarzschild to white transition
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Undergrad Proof of Lorentz transformation
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Undergrad Questions about a thought experiment involving time dilation
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Undergrad Is Measuring the One-Way Speed of Light Possible Near a Black Hole?
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Undergrad Black hole and singularity
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Graduate What kind of topology change does this Lorentzian metric describe?
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Undergrad General relativity question: Gravity clock
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Undergrad Formulating the Poincare group and its double cover
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High School Why Does the Speed of Light Max Out at 186,282 Miles Per Second?
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Undergrad Geodesics in Schwarzschild: Reparametrizing the Equations
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High School Very simple exercises in General Relativity
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Undergrad On the possibility of exploding a black hole
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Undergrad Basic questions about E=mc^2 energy conversion
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Undergrad Do black holes have magnetic fields?
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Undergrad SR-time dilation vs GR-time dilation on rotating Earth
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Undergrad Affine parameter and non-geodesic null curves
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Undergrad Where is the mistake in this derivation of Length Contraction?
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Graduate Energy-to-angular momentum ratio in EM v. gravity quadrupole radiation
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Graduate Quadrupole radiation formula for gravity
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Undergrad Special relativity & Synchronization of clocks
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Undergrad Frame fields and congruences of worldlines
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Undergrad Lorentz invariance of the 4-momentum
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High School Would an object in orbit change facing or orientation?
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Graduate A very peculiar emergent definition of gravity
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Undergrad The uniqueness of D=4
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Undergrad Why do objects follow a geodesic?
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Undergrad Increase in surface charge density in different frames of reference
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High School General relativity and frame of reference
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Undergrad Line element in Kerr coordinates at singularity
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Undergrad Trying to Fully Understand Mass Increase of Unstable Bonds
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Undergrad Help understanding proof of ds=ds' in Classical Theory of Fields
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High School Nalini Joshi's Time Travel Ideas
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Undergrad Constants of motion symmetric spacetimes
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Undergrad Speed of information-carrying radiation
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Graduate Zeroth law of black hole thermodynamics
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Undergrad Is Spacetime a Real Physical Entity or Merely a Conceptual Framework in Physics?
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Undergrad Quaternions and Special Relativity
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Undergrad Escape velocity near a black hole: Newtonian or Special Relativity?
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Undergrad Circumnavigating the Universe in Cosmos (1980)
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Undergrad Definition of time-independent scalar field in GR
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Undergrad Congruence of curves in spacetime
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Undergrad Distance between two light pulses
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Graduate Timelike curves on event horizon
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Undergrad Solution To Photon Trajectory Equation
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Graduate How to show spin ##= \pm 2/\omega## for a circ-polarized gravity wave
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Undergrad Inertial reference frame and Bondi k-calculus
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Undergrad Regarding centrifugal effects on the time dilation of a moving clock
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Undergrad A question about Curved Spaces: Gauss and Riemann (Einstein Gravity in a Nutshell by Zee)
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Graduate Stationary solutions to Klein Gordon equation in spherical symmetry
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Graduate Exact meaning of the mass M in the Kerr metric event horizon formula?
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Undergrad Handshake paradox involving the Starship Enterprise
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Graduate Metric of the "space" of 3d rotations
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Undergrad Spatial homogeneity condition for a free particle Lagrangian
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Undergrad Comparing Tick rates of clocks across Frames
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Undergrad What causes an accelerated clock to record less events
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Undergrad Symmetrical acceleration of Synchronised clocks
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Undergrad Doppler effect in transparent media and the index of refraction
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Undergrad Spaceship drive using symmetrical frame dragging?
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High School Can the same ruler have two different sizes?
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Undergrad Can Propeller Speeds and Wave Breaks Challenge the Speed of Light?
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Graduate Making sense of Dirac's rotation operator in "General Theory of Relativity"
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Undergrad Derivative w.r.t. time of relative position in special relativity
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Undergrad How Can I Get Published Without an Endorsement?
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Graduate Inferring coordinate change from the form of the metric
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High School Can We Use Space/Time Fabric to See the Past?
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