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 A problem with time dilation help?
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Graduate What is the relationship between space-time density and gravity?
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Graduate What if a black hole had a negative size ?
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Undergrad Hydrogen atom to 90% the speed of light
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Graduate *May be a stupid question* Does Oxygen/Nitrogen bend space-time?
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Graduate Is Spacetime Always Flat in Regions Without Mass?
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Undergrad Confusion regarding Time dilation ?
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Graduate Torsion in GR and Einstein-Cartan theory
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Graduate Bacteria Space Travel: Does Speed Affect Cell Division?
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Graduate How is twin paradox resolved in case of no/zero acceleration?
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Graduate Relativity Explained Via Movement, Not Time
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High School Gravity & Mass: Question about Affecting Something with No Mass
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Graduate What is the relationship between relativistic currents and Ohm's Law?
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Graduate Open and Closed Models in Cosmology
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Graduate Is Center-of-Mass Supraliminal?
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Graduate Relativistic Momentum: Is It a Vector in Relativistic Energy?
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Graduate How can I access to the following reference?
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Graduate Why does action have to be invariant?
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Graduate Gravity's Impact on Oxygen and Particle Movement: A Scientific Inquiry
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Graduate Issues with predicting Mercury's Orbit
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Graduate Conservation of energy in gravitational red shift
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Graduate Interchangeability of time and space
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Graduate Postulate of SR re speed of light
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Graduate What is the concept of four velocity and four force in special relativity?
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Undergrad Our 'Background' Speed and How it Fits with Time Dilation
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Graduate How is gravity described mathematically in general relativity?
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Graduate Understanding Proper Time and Arc-Length in GR Geodesic Curves
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Graduate Time Dilation Concept Confusion
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Graduate Question about time in Lorentz Tranformation
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Graduate Escaping the Schwarzchild Radius
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Graduate Studying Relativity: Speed Limit of c in All Inertial Frames?
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Graduate Can Equivalence Principle Be Violated?
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Undergrad Speed of light in non inertial frames
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Graduate Relativity & Light: Explaining an Observation Phenomenon
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Graduate In <Cosmology> written by Weinberg, in page 109
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Graduate Is length contraction an actual occurrence or merely an optical illusion?
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Graduate Whose Clock Wins in the Alice and Bob Time Dilation Paradox?
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Graduate Absolute Velocity of the Earth?
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Graduate Is Time Subjective or Objective in Spacetime?
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Graduate Understanding Space Distortion in General Relativity
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Einstein's The Field Equations of Gravitation Paper
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Graduate Covariant Derivative: Understanding $\partial_i e_j=\Gamma^{k}_{ij} e_k$
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Undergrad Is the speed of expansion of the universe faster than light?
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Graduate Laypersons problems understanding Black Holes
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Graduate What is the mathematical explanation behind red/blue shift caused by gravity?
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Graduate Time-Invariant Space: Metric ds^2 and Coordinates
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Graduate Help Me Reconcile This Thought Experiment | 65 Characters
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Graduate How can we test space-time for pseudo-Riemannian-ness?
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Graduate Does time stands still at c? And is room a point then?
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Graduate Are there any similarities between GR tensorial
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Undergrad Is Faster than Light Time Travel Possible?
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Graduate Question on Time Dilation Experiment
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Undergrad Speed of Gravity the Same in All Reference Frames?
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Graduate Gravitational Time Dilation - Is my head older than my feet?
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Undergrad Origins of the idea of a tachyon? (and a greeting)
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Undergrad Thoughts travelling faster than c
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Graduate Which Clock Slows Down with Time Dilation?
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Graduate Gradient of a tensor in cylindrical coordinates
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Graduate Does the expansion of Space require continuous energy?
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Graduate Polarization states via relativistic effect
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Graduate Where is potential energy in relativistic formula of energy?
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Graduate Can Electrons Overcome Gravity in a Black Hole?
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Graduate Gravity: A Matter of Spacetime Compression?
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Graduate How Does Relativity Affect Observations of Light by Alice and Bob?
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Graduate Writing Sci-fiction Graphic Novel need advisement in space travel
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Graduate Equivalence Classes in Physics: Tutorial Papers & Relationship to Units
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Graduate Wormholes & Conservation of Energy
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Graduate Connecting Two endpoints in space using a Wormhole.
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Posting Diagrams Multiple Times: Is it Possible?
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Undergrad I remember reading somewhere about how a wormhole lets you see
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Graduate Entropy as a measure of time in relativity
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Undergrad Can We Physically Handle Extreme Speeds in Spacecraft and Simulated Gravity?
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Graduate Action at a distance v curvative of space
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Graduate What Are the Radial and Tangential Accelerations in the Kerr Metric?
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Graduate Help with energy momentum relation.
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Undergrad Would a Conveyor Belt from Earth to Mars Have a Time Delay?
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Graduate Understanding Homothetic Vector Fields: Intuition and References
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Graduate Photon Time: 10B Years, 0 Seconds?
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Graduate Empirical verification of conditions for Hawking singularity theorem when Λ≠0?
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Graduate What is Einstein Notation for Curl and Divergence?
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Graduate Can we truly know the fate of objects in black holes?
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Graduate Mass of trapped photons vs. Mass of potential energy
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Graduate Don't fully get Lorentz equations
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Graduate Why is the Time component in the Space Time Interval negative?
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Graduate Momentum of massive classical free field
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Graduate How can local gravity be calculated in a gravitational field?
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Graduate Does Mach's Principle Work Both Ways?
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Graduate De Broglie wavelength shift in gravitational fields
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Graduate Is a (-,-,-,-) metric signature meaningful?
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Graduate How Does Gravitational Time Dilation Relate to Gravitational Red-Shift?
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Graduate Lorentz covaraince of differntial operator
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Undergrad Does the concept of a singularity defy the laws of nature?
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Undergrad Can a Box be Bigger on the Inside? | Dr. Who Fans
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Graduate Is Walking at Constant Latitude with Your Arm Pointing North Parallel Transport?
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Graduate A question about the relationship between light and time.
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Graduate Plausibility arguments for noninteraction of parallel beams of light
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Undergrad Discovering the Paradox of Being Your Own Grandfather in Futurama
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Graduate Hand-wavy proof of (part of) Birkhoff's theorem
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Graduate Can't make a clock out of light
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Graduate Can calculus find the momentum of light?
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