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 Looking for A.G. Walker's 1932 Fermi-Walker transport paper
- facenian
- · Replies 6 ·
High School Does time dilation affect the de Broglie wavelength of a muon?
- bobdavis
- · Replies 27 ·
High School What Does Hawking Mean by Negative Energy at the Big Bang?
- Physics Slayer
- · Replies 1 ·
High School Can a mirror reflect parallel light rays in sync?
- OWSOL
- · Replies 45 ·
Undergrad Are Kronecker delta with different index positions equivalent?
- Jim Lai
- · Replies 5 ·
High School Travel 7 Light Years at 50000km/s - How Long?
- Spockishere
- · Replies 12 ·
Undergrad Is Time Dilation Just a Misunderstanding of Clock Errors?
- paul1365
- · Replies 4 ·
High School Time dilation on rotating disk from the clocks' perspective
- Thadriel
- · Replies 21 ·
High School Can general relativity be interpreted as a varying ether?
- DanAil
- · Replies 18 ·
Graduate Christoffel symbols and curvature without a metric
- pervect
- · Replies 1 ·
Undergrad Does energy in the electric field contribute to inertial mass?
- Will Learn
- · Replies 16 ·
Undergrad Physical meaning of a spacelike geodesic
- accdd
- · Replies 62 ·
Graduate Can a conformal flat metric be curved?
- Kurvature
- · Replies 5 ·
Undergrad Radiate Single Charged Particle: Free Fall in Black Hole?
- accdd
- · Replies 1 ·
Undergrad Distance Contraction: Is D or D*sqrt(1-(v/c)^2) Traveled?
- Kairos
- · Replies 27 ·
Insights Rindler motion in special relativity: hyperbolic trajectories
- stevendaryl
- · Replies 29 ·
Graduate Generalize Special Relativity for Flat Spacetime
- Ans
- · Replies 8 ·
Undergrad Gravitoelectromagnetism: Why Equation Differs in Sources
- olgerm
- · Replies 1 ·
Graduate Affine Spaces and Vector Spaces
- vanhees71
- · Replies 82 ·
High School Does gravitational time dilation accumulate on mountaintops over millions of years?
- jeepdriver74
- · Replies 11 ·
High School Length, Time, and Velocity -- Which are fundamental quantities?
- Keith Koenig
- · Replies 50 ·
Undergrad Effects of Supermassive Black Hole Merger on Nearby Bodies
- Hornbein
- · Replies 2 ·
Undergrad Is acceleration an invariant in special relativity?
- Freixas
- · Replies 7 ·
Undergrad Superluminal laser dot on a screen observed by relativistic observer
- Halc
- · Replies 13 ·
Undergrad Difference between proper time and coordinate time
- Silviu
- · Replies 36 ·
Undergrad Length contraction in General Relativity
- knowwhatyoudontknow
- · Replies 64 ·
Graduate Why does Wald rewrite T^{acde}_b using two inverse metrics?
- madsmh
- · Replies 4 ·
High School Why are gravitons needed to explain gravitational attraction?
- lukegregor
- · Replies 8 ·
Undergrad Spacetime Curvature via Triangle
- Narasoma
- · Replies 2 ·
Undergrad How can metric components be defined as scalar products of basis vectors?
- Pencilvester
- · Replies 24 ·
High School Simple reasoning that the equivalence principle suggests curvature
- luinthoron
- · Replies 48 ·
High School Build a Time Dilation Clock for 8th Grade Science Project
- Dc2LightTech
- · Replies 25 ·
Undergrad Wilbert Zweistein's Objection to Equivalence Principle
- ergospherical
- · Replies 13 ·
Undergrad Tensor product of a 4-vector and tensor with shared indices
- Milsomonk
- · Replies 3 ·
Undergrad Can a Basis Vector be Lightlike?
- cianfa72
- · Replies 28 ·
Undergrad Can time run backwards in an accelerating frame?
- Gumby The Green
- · Replies 125 ·
High School Ride Gravitational Waves to Increase Speed?
- wcivch
- · Replies 6 ·
Graduate Proving $g(u,v)≠0$ with Linear Independence
- isaacdl
- · Replies 11 ·
High School Does this thought experiment show that Space must be curved?
- peterraymond
- · Replies 17 ·
Undergrad Relationship between Schwarzschild radius and event horizon
- accdd
- · Replies 11 ·
Undergrad How does the Schwarzschild metric relate to particle absorption?
- accdd
- · Replies 8 ·
Undergrad Why does the Rindler wedge seem timelike but the light cone spacelike?
- knowwhatyoudontknow
- · Replies 4 ·
Undergrad Energy conditions and non-physical phenomena
- accdd
- · Replies 5 ·
High School Do atoms stay bonded when an object crosses a black hole's event horizon?
- accdd
- · Replies 20 ·
High School Why is the BH Information Paradox Called a Paradox?
- Grinkle
- · Replies 8 ·
Graduate Magnetic field from the electromagnetic field tensor in Wald (4.2.22)
- carpinus
- · Replies 18 ·
High School How Can We Observe Black Holes Growing?
- mef
- · Replies 96 ·
Undergrad Newtonian expansion model vs GR explanation of cosmic redshift
- Pony
- · Replies 7 ·
High School Rotation of Galaxies: Mass vs Dark Matter?
- accdd
- · Replies 7 ·
High School Can another force dependent on stress-energy be weaker than gravity?
- accdd
- · Replies 3 ·
Graduate Why Gullstrand-Painlevé and Lemaître coordinates look different
- PAllen
- · Replies 8 ·
Undergrad Problem sets for practical general relativity calculations
- zwoodrow
- · Replies 2 ·
Undergrad Is there really nothing faster than light?
- SvenDahlhaus
- · Replies 40 ·
High School Energy Conservation w/ Charged Battery Time Travel
- Lars Krogh-Stea
- · Replies 3 ·
Undergrad Measuring distance to the event horizon with a rigid ruler
- mef
- · Replies 34 ·
Undergrad What is the Meaning of Lagrangian in Special Relativity?
- jbergman
- · Replies 7 ·
Graduate Anti-self Dual Part (2,2) Riemann Curvature Tensor
- abhinavabhatt
- · Replies 2 ·
High School Gravitational Lensing: Magnification of Galaxies
- Mikael17
- · Replies 5 ·
Undergrad Applying Reisenbach Transf. to EM Wave in Microwave Oven
- wnvl2
- · Replies 16 ·
Undergrad Measuring light speed in curved spacetime near a Schwarzschild black hole
- mef
- · Replies 13 ·
Undergrad Detecting gravitomagnetic deflection of a laser through a spinning cylinder
- olgerm
- · Replies 8 ·
Undergrad Time Travel in Newtonian Spacetime: Is it Possible?
- accdd
- · Replies 2 ·
Undergrad Why does the accelerated traveler's clock show less elapsed time than Earth's?
- Freixas
- · Replies 14 ·
High School Can Accelerate at Constant g in Own FoR?
- S Holtom
- · Replies 33 ·
Undergrad Why are perfect fluids needed in general relativity?
- accdd
- · Replies 15 ·
High School Why is the relative speed of two cars less in Lorentz than Galilean transforms?
- David Lewis
- · Replies 10 ·
Undergrad How Does Time Dilation Affect the Twin Paradox in Special Relativity?
- sennetor
- · Replies 9 ·
Undergrad Does constant velocity motion in relativity prevent radiation emission?
- accdd
- · Replies 23 ·
Undergrad Isotropy of the speed of light
- andrew s 1905
- · Replies 264 ·
Undergrad General Relativity: Is it Local?
- accdd
- · Replies 2 ·
Undergrad Deriving Special Relativity from Particle Indistinguishability
- accdd
- · Replies 3 ·
Undergrad Gravitational vs. Electromagnetic Waves: What's the Difference?
- accdd
- · Replies 20 ·
High School How much energy to create a 1000 kg artificial black hole?
- Devin-M
- · Replies 11 ·
High School Robert Wald's General Relativity: Energy-Momentum Relation
- carpinus
- · Replies 8 ·
Undergrad Proof of Special Relativity w/ Michelson–Morley Experiment
- FMJalink
- · Replies 20 ·
Graduate Alcubierre Metric: York Time Cause and Effect
- MattRob
- · Replies 3 ·
Undergrad Light speed independent of source
- Martyn Arthur
- · Replies 22 ·
Undergrad Understand Poynting Density of Flow of Energy w/Weak Physics Background
- Mike Karr
- · Replies 9 ·
High School Can gravitational waves have wavelengths as large as the solar system?
- DaveC426913
- · Replies 15 ·
Graduate Does Spacetime Absorb Energy in General Relativity?
- Suekdccia
- · Replies 17 ·
Graduate MTW Gravitation: Exercise 5.1 | Beginner GR Stress-Energy Tensor Symmetry
- Mike Karr
- · Replies 15 ·
Undergrad Why distinguish relative motion from relative acceleration in the twin paradox
- Martyn Arthur
- · Replies 16 ·
Undergrad Reichenbach Synchronisation: Proving i=r
- wnvl2
- · Replies 3 ·
Undergrad A paradox for two moving protons?
- FranzDiCoccio
- · Replies 30 ·
Graduate Local phase invariance of complex scalar field in curved spacetime
- Tertius
- · Replies 2 ·
High School Newton's third law for gravity in general relativity
- Giuly
- · Replies 15 ·
Undergrad About global inertial frames in GR
- cianfa72
- · Replies 78 ·
High School What conditions would create a wormhole in general relativity?
- Andre_86
- · Replies 3 ·
High School Can Push Travel Faster Than Light?
- PCNerdz
- · Replies 5 ·
Undergrad Gravity on the Moon vs. on the spinning Earth
- jon2
- · Replies 10 ·
High School Do accelerated and gravitational clocks slow at the same rate?
- calinvass
- · Replies 58 ·
Undergrad Why does a body at rest move if Gravity is not a force?
- zoltrix
- · Replies 70 ·
High School Gravitational Force acting on a massless body
- Lunct
- · Replies 67 ·
Undergrad Rocket landing in cylinder: length contraction paradox
- wnvl2
- · Replies 50 ·
Undergrad Why does -c²t² + x² approach 0 as β → 1 in Lorentz transformations?
- Samama Fahim
- · Replies 33 ·
Undergrad Is general relativity fundamental or an effective theory?
- Jamestein Newton
- · Replies 1 ·
High School A difficulty with the equivalence of all inertial reference frames
- JuanGC
- · Replies 28 ·
High School Is the Bekenstein-Hawking entropy formula based on logarithm base 2?
- gerald V
- · Replies 11 ·
Graduate Energy-Momentum Tensor for 2-Body Problem: Approach
- captainbleak
- · Replies 2 ·
High School Can You Become a Black Hole from Approaching Light Speed?
- bbbl67
- · Replies 25 ·