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 Do I arrive before a light-speed train if I jump off the front?
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High School Motion to Rest: What Does the Universe Agree On?
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Graduate Math Questions in Lorentzgroup: Covariance/Contravariance Explained
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Graduate A question on a tweek of the Twin Paradox
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High School Why Can't I See the Earth Rotating Below Me?
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Graduate Who first studied variable speed of light? - Einstein
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Graduate Speed of Light: Universe's Expansion After Big Bang
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Graduate What does it mean: transforms like a vector
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Graduate Rank-2 tensor: multiple definitions
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Graduate Does gravity affect to wavelengths?
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Graduate The importance of the relative movement
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Graduate Weyl tensor in 2 dimensions- confused
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Graduate Understanding the Passage of Objects through the Event Horizon of a Black Hole
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Graduate Relativity and matter by Pauli
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Graduate Applying Forces to Particles: Questions Answered
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Undergrad Caught Between Two Gravitational Fields
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Graduate Is General Relativity Dependent on the Existence of a Manifold?
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Graduate Birkhoff's Theorem: Exterior Solution to Einstein's Field Equations
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Graduate Why Does Space/Time Not Cause Friction?
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Graduate When Clocks Meet: Investigating Time in Einstein's Special Relativity
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Graduate Exercise 2.5 in Misner, Thorne and Wheeler
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Graduate Pushing with a lorentz contracting stick
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Graduate Is the Sun invisible at relativistic speeds? Part II
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Graduate Quick question, Komar integral derivation in Wald
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Undergrad Speed of Gravity: 299792458 m/s?
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Graduate Relativity in a Rotating Space Station
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Graduate Black holes , gravity upper limit
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Graduate Recommendaton for Clarifying Special Relativity
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Graduate Formulating Position Vector with f(t)
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Graduate Can Observers See the Future in Relativity?
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Graduate Finding the 4x4 Cofactor of a Covariant Metric Tensor g_{ik}
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Graduate Maxwell's Equations in Curved Space-time
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Graduate Reconciling APOD BH Videos w/ Physics Forums Discussion
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Graduate Classification of Gravitational Theories
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Graduate Why do objects fall through curvature of spacetime?
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Graduate Is a Topological Action Defined by the Underlying Space?
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Graduate Singularity Mechanics? Blackhole Spin
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Graduate The reason why you can't accelerate to light speed
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High School Terminology of Convert: What's the Right Term?
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Graduate Understanding Mass in Relativity Theory: Definitions and Conflicting Views
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Graduate Photon energy changing due to Dopplershift?
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Graduate Measuring velocity in empty space
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Graduate Distances between planet and observer near BH
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Graduate Relativity of simultaneity objections
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Graduate How could a photon travel at lightspeed if it has mass?
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Graduate Accelerating Expansion of Space-Time and Implications for Time Itself
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High School Space Time Explained: Physics & E=mc^2
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Graduate Objects accellerating due to each other's gravity
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Graduate Does Time Really Flow Backwards?
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Graduate Penrose Diagrams - Introduction
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Undergrad Observer S' on a rocket vs an observer S on Earth
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Graduate Need flat spacetime to define mass and spin?
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Graduate Confused about length contraction
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Graduate Time & Speed of Photon: Questions Answered
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Undergrad Does Energy Gravitate? A Check of Understanding
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Graduate Does a photon experience time when slowed down by gravity?
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Graduate Condition for close timelike curve?
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Graduate Mass & Velocity: Gaining Momentum with Speed
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Graduate Seeking clarification of time dilation
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Graduate Why we won't notice anything special when crossing the horizon?
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Graduate Adding subluminal and superluminal velocities.
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Graduate Acceleration and gravity, conceptual problems.
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Graduate Upper limit for black hole’s rotational speed
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Graduate What is the most fundamental axiom of General Relativity?
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Graduate Reading Einstein's book & confused about simultaneous events
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Undergrad Why is light the fastest possible speed
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Undergrad Gravity at its maximum range question.
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Graduate Exterior derivative identity in vacuum space-time
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Graduate Radial Schwarzschild geodesics - again
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Graduate Riemann curvature scalar, Ricci Scalar.What does they measure ?
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Graduate Unified or Fractured? Universe Info Transmission Speed
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Graduate How does matter accelerate in a gravitational field
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Graduate Muon Lifespan: How We Measure Decaying of Muons
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Graduate Can something with zero rest mass (photon) curve spacetime?
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Graduate Moving Masses & Doppler Shifts in Flat Space-Time
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Graduate What is the Form of Riemann Tensor in 3D?
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Graduate Notation for time in a relativistic graph
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Graduate Wald Lemma 8.1.1-help with proof
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Graduate Difference between black hole solutions and wormhole solutions
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Graduate Black Holes & Time: A Collision of Forces
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Undergrad Special relativity and stars' masses
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Graduate Riemann Curvature Scalar Differs in Landau & MTW
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Graduate Questions on Weinberg Cosmology Book
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Graduate Lorentz transformation derivation. What exactly is wrong?
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Graduate Sending information faster than speed of light?
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Undergrad *If* the ISS is freely falling, doesn't that mean it's following
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Graduate Does light exist outside of time ?
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Graduate Time travel + conservation laws
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Undergrad Group velocity and phase velocity of a matter wave
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High School Listening to the Feynman tapes on youtube, and I have a question.
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Undergrad Confusion with Michelson-Morley Experiment
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Undergrad Two questions about Special Relativity
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Graduate More on gravitational time dilation and escape velocity.
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Undergrad Photons Affected by Pseudo Forces | Hyperspace by Michio Kaku
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FAC Suggestion for Clarifying SR Theory
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Graduate Is Schwarzschild metric more intuitive?
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Graduate Change in position/t greater than speed of light?
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Graduate Is LET an Interpretation of SR?
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Graduate Mach's principle, GR and the nature of space
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Graduate Lamp color before and after a phase of acceleration
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