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.
Threads
Undergrad Klein-Gordon: Schwarzschild Metric, Physically Acceptable?
- Vitani1
- · Replies 7 ·
Undergrad Is the premise of the Michelson–Morley argument still valid?
- Killtech
- · Replies 31 ·
Undergrad Interpretation of Potential Energy as Field Property
- zonde
- · Replies 5 ·
Undergrad Compute EOM for Spin Connection from Einstein-Palatini Action
- Lactose
- · Replies 1 ·
Undergrad Can time dilation explain galaxy rotation curves?
- sha1000
- · Replies 7 ·
Undergrad Solving the Flickering Light Paradox
- astrodummy
- · Replies 20 ·
Undergrad Computing extrinsic curvature of a bubble brane in GR
- John Greger
- · Replies 3 ·
Undergrad Source of Gravity of heavy mass as per GTR
- eaglechief
- · Replies 14 ·
High School Does a supernova explosion reach distant objects instantly or after light travel time?
- vcandy
- · Replies 17 ·
High School Is time a true variable in the scheme of things?
- Suppaman
- · Replies 73 ·
Undergrad Why doesn't gravity release people on the opposite side of Earth?
- Brooksie
- · Replies 8 ·
Undergrad Movement of a guitar string at relativistic speeds
- Joda
- · Replies 61 ·
Graduate The "no metric, no nothing" view
- jake jot
- · Replies 2 ·
Undergrad Can Time Travel Into the Future Really Happen?
- Azrion
- · Replies 19 ·
Undergrad 4 spaceships are pulling a membrane through an asteroid belt
- eaglechief
- · Replies 8 ·
High School Why do you need a light clock?
- Atstill77
- · Replies 7 ·
High School Why don't units cancel when comparing rates in time dilation?
- jaketodd
- · Replies 24 ·
Undergrad What is the four-momentum of a photon?
- jbergman
- · Replies 17 ·
Undergrad Can GTR and STR work in a 9-dimensional spacetime?
- eaglechief
- · Replies 6 ·
High School Measuring the One Way Speed of Light
- RandyD123
- · Replies 171 ·
High School On the four dimensions of special relativity
- trees and plants
- · Replies 22 ·
High School Why doesn't c² equal c if c is a constant?
- curiousat61
- · Replies 8 ·
Undergrad Cosmic Censorship: Does it Hold?
- john baez
- · Replies 2 ·
Graduate Killing vectors and event horizons in the Kerr metric
- JD_PM
- · Replies 8 ·
Graduate Has relativistic thermodynamics temperature debate been resolved?
- johnscitech
- · Replies 20 ·
High School How do tidal forces arise from spacetime curvature without invoking forces?
- Karl Coryat
- · Replies 25 ·
Undergrad What is the Role of Matter in General Relativity's Lagrangian?
- dsaun777
- · Replies 10 ·
Graduate Difference between Λ^ν_μ and Λ^ν_μ in tensor notation
- LagrangeEuler
- · Replies 16 ·
Undergrad Why does the particle's northward velocity decrease when the observer accelerates east?
- em3ry
- · Replies 6 ·
High School A few questions about the covariant derivative
- etotheipi
- · Replies 7 ·
Undergrad Gravity: Compounded Space (Time) Signal?
- CuriousGiles
- · Replies 5 ·
Graduate Geodesic Eq Derived from Einstein Field Equations?
- Intrastellar
- · Replies 25 ·
Undergrad If the sun disappeared, would gravity persist for 8 minutes?
- Byron Forbes
- · Replies 20 ·
Undergrad Conservation of energy in general relativity
- Qwet
- · Replies 42 ·
Undergrad Recovering Newton's energy conservation law for an Earth's lab
- epovo
- · Replies 35 ·
Undergrad Is coordinate speed affected by gravitational waves?
- Haorong Wu
- · Replies 17 ·
Undergrad Hawking Radiation: Info vs Semanticity? - Hossenfelder
- gerald V
- · Replies 4 ·
Undergrad Spacetime invariance algebraic proof
- john t
- · Replies 8 ·
Graduate The g_ij as potentials for the gravitational field
- dx
- · Replies 108 ·
Undergrad The Sub Photon Sphere Escape Game
- .Scott
- · Replies 8 ·
Undergrad Kerr black hole ergosphere and faster-than-light displacements
- Marilyn67
- · Replies 19 ·
Undergrad How does the radius excess formula relate to the mass of a sphere?
- italicus
- · Replies 6 ·
High School Active and passive transformations of scalar fields
- etotheipi
- · Replies 15 ·
High School Light clock: why don't Δt and 2D/c match in the stationary frame?
- Point Conception
- · Replies 17 ·
Undergrad Escape trajectories near a Schwarzschild black hole photon sphere
- .Scott
- · Replies 3 ·
Undergrad Solving Relativistic Inelastic Collisions: 150 GeV Energy
- Eirik
- · Replies 8 ·
High School Transforming the Electric Field Measured by an Observer with 4-velocity U
- etotheipi
- · Replies 2 ·
Undergrad Solving the Spherically Symmetric Einstein Equation
- Tomas Vencl
- · Replies 3 ·
High School Gravitational Wave System and Locations
- Eumeme
- · Replies 2 ·
High School 2020 Nobel Prize in Physics
- martinbn
- · Replies 48 ·
High School Value of this 'Science' Channel as quick intro
- D.S.Beyer
- · Replies 38 ·
Undergrad Observing Black Holes in Finite Time
- kmm
- · Replies 10 ·
Undergrad Self-Study General Relativity: After Multivariate Calc in HS
- SirMadame
- · Replies 3 ·
High School Paradox of Simultaneous Flashing in a Moving Triangle of Lights
- O Great One
- · Replies 18 ·
High School How can two ships pass each other twice at the same moment?
- O Great One
- · Replies 15 ·
High School Does combustion convert a tiny amount of mass to energy?
- iVenky
- · Replies 12 ·
Undergrad Sound and light speed: which statements are true?
- TheGeneMan
- · Replies 1 ·
High School Contradictory time dilation equations
- O Great One
- · Replies 13 ·
Undergrad Can instantaneous teleportation from point A to B cause time travel?
- danielhaish
- · Replies 17 ·
Undergrad What software can I use to make space-time diagrams?
- phoenix-anna
- · Replies 5 ·
Undergrad Why does the Riemann curvature tensor vary on a 2D sphere?
- epovo
- · Replies 4 ·
High School Event horizon for observer within main horizon
- Swamp Thing
- · Replies 1 ·
High School How do E and B fields oscillate if time dilation approaches zero for light?
- jaketodd
- · Replies 3 ·
Undergrad Does time dilation cause different aging rates for people?
- richengle
- · Replies 27 ·
Undergrad Does Mercury's precession depend on the observer's gravitational field?
- Mickey1
- · Replies 11 ·
Undergrad How to communicate between planets?
- Haorong Wu
- · Replies 26 ·
Undergrad Thought Exp: Gen Relativity & Time Dilation
- starkreactor
- · Replies 4 ·
High School Does a traveling radioactive mass decay slower due to time dilation?
- Kairos
- · Replies 15 ·
Undergrad Velocity Addition and Doppler Effect: Explained
- Kairos
- · Replies 5 ·
High School How to derive the continuity equation for a perfect fluid?
- etotheipi
- · Replies 17 ·
High School First Experimental Confirmation of GR
- phoenix-anna
- · Replies 8 ·
Undergrad Are Derivatives of the Metric Different in Flat Spacetime?
- etotheipi
- · Replies 6 ·
Undergrad Does a magnetic needle rotate when a charged line moves past an observer?
- hjwu
- · Replies 2 ·
Undergrad Can you create a naked singularity by charging an extreme Kerr black hole?
- arusse02
- · Replies 2 ·
High School Time Travel Possibility with Two Black Holes Orbiting Each Other
- slimak
- · Replies 14 ·
High School Experimental Confirmation Length Contraction Velocity Addition
- jeremyfiennes
- · Replies 27 ·
High School Why can't energy or information go faster than light?
- danielhaish
- · Replies 32 ·
High School Does spacetime curvature increase or decrease the distance between two points?
- Martian2020
- · Replies 62 ·
Undergrad Does constant scalar curvature determine if a 3-torus is finite or infinite?
- George Keeling
- · Replies 12 ·
High School Can photons have relativistic mass from E=mc²?
- virgil1612
- · Replies 13 ·
Undergrad Do time dilation and length contraction both have to be true in special relativity?
- Charlie K Trout
- · Replies 6 ·
Undergrad Einstein Field Eqns: East/West Coast Metrics
- DuckAmuck
- · Replies 6 ·
Undergrad Understanding Feynman's Relativistic Electric Field Equation
- bryanso
- · Replies 3 ·
Undergrad Which clock runs slow when twins move apart symmetrically?
- Marilyn67
- · Replies 33 ·
Undergrad Is it feasible to measure one way speed of light this way?
- kostarak
- · Replies 52 ·
Graduate Levi-Civita Connection & Length of Curves in GR
- Blub
- · Replies 9 ·
Undergrad How to Change Between Unit Systems w/ ##c \ne 1, \hbar \ne 1, G \ne 1##
- Haorong Wu
- · Replies 4 ·
High School In the twin paradox without acceleration, who ages less?
- imsmooth
- · Replies 5 ·
High School Einstein's Universe (1979) - Nigel Calder, Peter Ustinov
- robphy
- · Replies 2 ·
High School Transform to accelerating coordinates
- etotheipi
- · Replies 18 ·
Graduate Gravity Theories: GR vs Alternatives - Post 2018
- andrew s 1905
- · Replies 1 ·
High School Visualize 2D Intrinsic Curvature of Spacetime (1s+1t) in 3D
- Martian2020
- · Replies 14 ·
Undergrad Momentum Conservation in Special Relativity: mwu
- Feynmanisthegoat
- · Replies 3 ·
Undergrad Inverting the metric coefficients in the Schwarzschild line element
- Bishal Banjara
- · Replies 32 ·
Undergrad Proper time to reach the singularity of a Schwarschild black hole
- Reggid
- · Replies 4 ·
Undergrad Why don't relative time dilation and velocity addition lead to paradoxes?
- jkbhagatio
- · Replies 11 ·
Undergrad Why does an object initially at rest begin to fall?
- Grasshopper
- · Replies 24 ·
Undergrad Does Light Curve Spacetime?
- trees and plants
- · Replies 11 ·
High School CMB temperature measurements and relativity of simultaneity
- Ideassimples
- · Replies 33 ·
Undergrad Does a photon falling toward a black hole slow down in Schwarzschild coordinates?
- snoopies622
- · Replies 18 ·