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 When Does a Train Passenger Experience Complete Darkness in a Tunnel?
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Undergrad Matrix form of metric component transformation?
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Undergrad Energy and reference frames
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Undergrad GR as Gauge Theory
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High School Can we say that everything on the planet is made up of energy or matter?
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Graduate A better way of talking about time?
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Undergrad Are Space and Time Just an Illusion in General Relativity?
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Graduate Curvature with different connections on the two-sphere
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Undergrad Determinism & General Relativity: A Physics Primer
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Undergrad Transformation Riemann tensor to an accelerating frame
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Undergrad SR: GA Multivector vs. Tensor notation, Maxwell's equations
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Undergrad Time dilation for two observers in relative motion
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Undergrad Electromagnetic field in different reference frames
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Graduate Speed of Light for Bonnor Beam
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Undergrad Time dilation and the human body
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Undergrad If electrons can be pointlike particles, why can't black holes?
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Graduate Is Fatio–Le Sage's theory of gravitation an entropic gravity?
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High School Is time an illusion?
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Undergrad Definition of tangent vector to a timelike geodesic
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Undergrad Tensor field from a covariant derivative operator (affine connection)
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Undergrad Can anyone clarify the relativistic twin paradox for me?
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Graduate Calculating geodesic equation from Hamiltonian in presence of EM
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Undergrad Why does laser beam hit the same target when fired?
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Undergrad Lorentz transformation on mode functions
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Undergrad A six-vector is related to a 2nd rank antisymmetric tensor in Minkowski Spacetime?
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Undergrad Is the weak field limit valid for the Brans-Dicke scalar field?
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Undergrad Robert B. Laughlin (Physics Nobel Laureate, Stanford University)
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Undergrad What about the Big Ben Paradox?
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Undergrad Using 4-derivative
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High School Special relativity thought: Traveling to the future relative to a particle
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High School Imaginary distance is nonsense
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High School c^2 in Einstein‘s theory of relativity
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Graduate Special Relativity in Rotating Reference frame
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Undergrad A question about the speed of light and electromagnetism
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Undergrad The Lorentz factor gamma and proper time
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Undergrad Can the intersection point of two light beams exceed the speed of light?
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Undergrad Need opinions on Youtube video: "From constant moving charge to SR"
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Undergrad A thought experiment on simultaneity
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Undergrad Speed of Light & Bullet
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Undergrad Question about length contraction and repulsive force
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Undergrad A matter of time dilation: how much time has actually passed?
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Graduate Different time coordinates due to different velocities
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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 Why can coefficient "a" between spacetime intervals depend on velocity between systems?
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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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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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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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