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 Synchronizing clocks in an inertial frame if light is anisotropic
- James Hasty
- · Replies 67 ·
High School Why Do Events Freeze For Me at the Speed of Light?
- RobbyQ
- · Replies 4 ·
Undergrad Revisiting the Light Clock
- DmitryS
- · Replies 25 ·
Undergrad How does parallel transport on a sphere work physically?
- geordief
- · Replies 58 ·
High School Does a shadow contract when an object moves at speed c?
- Mohiaz
- · Replies 14 ·
Undergrad Can a Gyroscope in a Satellite Detect Orbit?
- zanick
- · Replies 51 ·
Undergrad Physical Interpretation of Frame Field
- cianfa72
- · Replies 41 ·
Undergrad Is this another "paradox" or a veritasium mistake?
- mgkii
- · Replies 28 ·
Graduate Assumptions of Hawking-Penrose 1970 Singularity Theorem
- Cerenkov
- · Replies 35 ·
Undergrad Gyroscope angular momentum: direction and curvature
- HansH
- · Replies 2 ·
Undergrad Does a person's mass affect time?
- Johndough_
- · Replies 6 ·
Undergrad About the notion of non-standard inertial frame
- cianfa72
- · Replies 22 ·
Undergrad Is using r as a coordinate in Birkhoff's theorem a limitation?
- Pencilvester
- · Replies 22 ·
Undergrad Length contraction of electrons versus nuclei in magnetism explanation
- curiousP
- · Replies 5 ·
Undergrad The Einstein Clock aka Light Clock
- DmitryS
- · Replies 34 ·
High School Train Fall Paradox
- anuttarasammyak
- · Replies 6 ·
Undergrad Integration of energy-momentum pseudotensor for Kerr BH
- anuttarasammyak
- · Replies 4 ·
Undergrad Why is the speed of light the same everywhere in the Universe?
- Rick16
- · Replies 64 ·
Graduate Does general relativity uniquely determine the Poynting vector?
- coquelicot
- · Replies 38 ·
Undergrad Relativity of simultaneity in actuality
- vibhuav
- · Replies 12 ·
High School Reciprocal time dilation
- fuentes1979
- · Replies 15 ·
High School Photon Energy Without Rest Mass – How?
- Uncle Thi
- · Replies 19 ·
Undergrad The wave equation interpretation of special relativity
- gentzen
- · Replies 10 ·
High School Is there a white hole inside every black hole?
- marees
- · Replies 22 ·
Undergrad Synchronizing clocks at different locations to measure speed of light
- ESponge2000
- · Replies 58 ·
Undergrad An invariant while crossing the horizon
- Tomas Vencl
- · Replies 7 ·
Undergrad I don't see how a black hole's event horizon can be crossed
- Foretranimal
- · Replies 73 ·
Undergrad Variation of the lightning train thought experiment
- FeynmanFtw
- · Replies 26 ·
High School Project GRE^2AT - GR on Mt. Ranier
- DaveC426913
- · Replies 5 ·
Undergrad How Is Intrinsic Curvature Measured in Higher Dimensions Like 4D Spacetime?
- geordief
- · Replies 19 ·
Undergrad Conventionality of the One-Way Speed of Light
- MrRobotoToo
- · Replies 6 ·
High School Trying to calculate proper time of worldlines using rotating frames
- Karin Helene Elise
- · Replies 35 ·
Graduate Reconciling units for the Einstein and Landau-Lifshitz pseudotensors
- Kostik
- · Replies 3 ·
Undergrad What Are the Limits of the Universe According to Cosmologists?
- .Scott
- · Replies 47 ·
Graduate Dirac's integral for the energy-momentum of the gravitational field
- Kostik
- · Replies 38 ·
Graduate Does relativity necessarily imply the block universe model?
- ojitojuntos
- · Replies 45 ·
High School Could we ever create a black hole?
- atlanticus
- · Replies 5 ·
Undergrad Follow-up Einstein Definition of Simultaneity for Langevin Observers
- cianfa72
- · Replies 3 ·
Undergrad Symmetry of motion in the special theory of relativity
- qnt200
- · Replies 37 ·
Undergrad Hawking area law confirmed from GW250114 black hole merger
- fresh_42
- · Replies 9 ·
Undergrad A sufficient condition for integrability of equation ##\nabla g=0##
- Jianbing_Shao
- · Replies 71 ·
Undergrad Follow-up on the Expanding Universe Insight article
- cianfa72
- · Replies 2 ·
Insights Relativator (Circular Slide-Rule): Simulated with Desmos - Insight
- Greg Bernhardt
- · Replies 1 ·
Undergrad How do Tensors "work" in relation to linear algebraic objects?
- Sciencemaster
- · Replies 7 ·
Undergrad Does kinetic energy cause time dilation instead of motion itself?
- mr John wheeler
- · Replies 9 ·
Graduate 1-Way Speed of Light
- James Hasty
- · Replies 42 ·
Graduate Gravitational Analysis of Wide Binaries
- juggler
- · Replies 13 ·
Undergrad Mass conservation in black holes
- Ranku
- · Replies 8 ·
High School How can a black hole absorb matter?
- Line_112
- · Replies 31 ·
Undergrad How length contraction and time dilation explain constant c in opposite directions
- Amin2014
- · Replies 4 ·
Undergrad Can this experiment break Lorentz symmetry?
- Asaad-Hamad
- · Replies 35 ·
Undergrad MTW 21.26: deriving junction condition a+ + a− = 0 for dust shell
- JimWhoKnew
- · Replies 5 ·
Undergrad Eddington’s margin of error
- Jedothek
- · Replies 4 ·
High School Can frame dragging do this?
- Ankit Doshi
- · Replies 1 ·
Undergrad Why did physicists abandon absolute simultaneity for relativity of simultaneity?
- Iskandarani
- · Replies 25 ·
Graduate Is there any topology behind factor 2 in Schwarzschild radius?
- Anton Rize
- · Replies 11 ·
Graduate Is the constancy of c a postulate or a derivable theorem?
- Iskandarani
- · Replies 13 ·
Undergrad How do non-diagonal indices of a metric allow for local flatness?
- Sciencemaster
- · Replies 22 ·
Undergrad Transformation for Lemaitre coordinates
- Dale
- · Replies 8 ·
High School What reference frame is used for the velocity v in the Lorentz transformation?
- Huangdongcheng
- · Replies 53 ·
High School Oberth Effect Near Sag A*
- Devin-M
- · Replies 35 ·
Graduate Error in Landau-Lifshitz Vol 2, equation (2), page 277
- shin1980
- · Replies 10 ·
High School Debating the Validity of a Conversion Factor for Mass-Energy Equivalence
- suoercat
- · Replies 13 ·
High School Can expanding electromagnetic radiation be quantized using E=mc²?
- physicsforman
- · Replies 11 ·
Undergrad Gravitation (MTW) Misner Thorne Wheeler - 50 years (RIP) C.W.Misner
- robphy
- · Replies 9 ·
High School Conservation of kinetic energy in expanding space
- rocknrollkieran
- · Replies 25 ·
Graduate A global energy conservation law in general relativity
- Kostik
- · Replies 36 ·
Undergrad Gravitational lensing of gravitational waves - real?
- Al_
- · Replies 3 ·
Graduate Uncertainties in the proof of Proposition 4.4.2 in Hawking and Ellis
- gasgas
- · Replies 2 ·
Graduate Weinberg's proof of ##{T^{\mu\nu}}_{,\nu}=0## for a perfect fluid
- Kostik
- · Replies 2 ·
Graduate How do you convert the Pound–Rebka redshift into time variation?
- ARChohan
- · Replies 6 ·
High School Relativistic contraction factor
- south
- · Replies 8 ·
Graduate Looking for linear frame dragging formula
- Jonathan Scott
- · Replies 3 ·
Undergrad Freefall and gravity
- Ranku
- · Replies 10 ·
Graduate Dirac's comprehensive action principle: why equations are not all independent
- Kostik
- · Replies 1 ·
High School Time dilation for two clocks at different altitudes on Earth
- zuz
- · Replies 14 ·
Graduate Deriving Dirac's Eq. (27.4) for momentum density variation in dust
- Kostik
- · Replies 50 ·
Undergrad How does GR deal with pointlike objects with mass?
- JC_Silver
- · Replies 5 ·
Undergrad Shwartzschild coordinate system
- omidj
- · Replies 5 ·
Undergrad How to calculate basis vectors from metric tensor (as a matrix)?
- Tachytaenius
- · Replies 6 ·
Graduate Weyl tensor and coordinate acceleration
- Povel
- · Replies 12 ·
High School Geometric and arithmetic means and contraction factor
- south
- · Replies 6 ·
Undergrad Does a square light clock depend on speed?
- south
- · Replies 8 ·
High School Gravity and speed of information for orbiting planets
- HansH
- · Replies 22 ·
High School Navigation inside a warp bubble and causality violation
- Luis
- · Replies 22 ·
Graduate Why does Weinberg discard fourth-order spatial Ricci components in chapter 9?
- LordShadow_05
- · Replies 5 ·
Graduate Singularity Formation and Breakdown Ricci Tensor
- Alien101
- · Replies 3 ·
Graduate The Causal Bootstrap Paradox in General Relativity
- Alien101
- · Replies 10 ·
Undergrad Theoretically, can perfectly flat spacetime exist in the Universe?
- John Constantine
- · Replies 31 ·
Undergrad Reframing Light Bending Using Density Instead of Radius
- Owe Kristiansen
- · Replies 20 ·
Undergrad Why does ct appear in the Lorentz transformation for 4-velocity invariance?
- omidj
- · Replies 11 ·
Undergrad Intuitive look at bending of light by gravity
- Owe Kristiansen
- · Replies 25 ·
Undergrad A "continous" gravitational field formula r=0 to infinity
- Owe Kristiansen
- · Replies 16 ·
Graduate Question on Dirac's derivatives of the 4-velocity w.r.t. coordinates
- Kostik
- · Replies 53 ·
Graduate Sidney Coleman's Lectures on Relativity: New Book by CUP
- physicsworks
- · Replies 5 ·
Graduate Does the New Paper on Singularities Offer Proof of Their Existence?
- windy miller
- · Replies 6 ·
Graduate Tensors in null basis
- Antarres
- · Replies 9 ·
Undergrad ##\epsilon_{ijk}## in terms of ##\delta's##
- brotherbobby
- · Replies 3 ·
High School Does the gravitational distortion of mass still exist in the past?
- Giblet
- · Replies 28 ·
Undergrad Missing proof of the Shell theorem in General Relativity
- Bosko
- · Replies 34 ·