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
High School Can Relativistic Mass Create a Black Hole?
- Aerodyn
- · Replies 4 ·
High School Pound & Rebka Experiment: Earth's Spin Rotation Speed
- BeedS
- · Replies 32 ·
Undergrad 3 clocks thought experiment - Absolute vs. relative aspects?
- Friggle
- · Replies 50 ·
High School LIGO Back Online: Upgraded Detector to Spot Fainter Gravitational Waves
- phinds
- · Replies 2 ·
High School Does time dilation change the measured speed of an event?
- Speady
- · Replies 35 ·
Undergrad Can two objects in freefall have different relative velocities?
- Ranku
- · Replies 26 ·
Undergrad Lorentz metric sign convention in Adler's relativity book
- mpresic3
- · Replies 32 ·
Undergrad Constraints on metric-compatible connections from compatibility equations
- Jianbing_Shao
- · Replies 62 ·
High School Does time dilation work like relative velocity with light speed constant?
- gatztopher
- · Replies 45 ·
High School Can two travelers have different proper times without knowing their relative motion?
- villy
- · Replies 51 ·
High School Perception of Velocity in Special Relativity
- BadgerBadger92
- · Replies 42 ·
High School Why does Einstein multiply dt by c in the spacetime interval ds2?
- Pedroski55
- · Replies 22 ·
Undergrad Why do strong fields complicate our understanding of singularities?
- iuvalclejan
- · Replies 33 ·
Undergrad Notation for down-arrow and subscript 1 in equations 4.6
- mpresic3
- · Replies 3 ·
Graduate Interior volume of a black hole
- PeterDonis
- · Replies 23 ·
Undergrad Why is the Einstein tensor zero in Schwarzschild geometry if there's a central mass?
- Joe Prendergast
- · Replies 18 ·
Undergrad How fast does the particle go through spacetime?
- student34
- · Replies 20 ·
High School What is the metric for a bag-of-gold spacetime?
- Onyx
- · Replies 9 ·
High School How do Black Holes Grow? A Far-Away Observer's Perspective
- Rene Dekker
- · Replies 67 ·
Undergrad Inertial Gravity in Relativistic Geodesics - Forum Discussion
- Thytanium
- · Replies 11 ·
Undergrad Gravitational field modulation of a moving mass
- synch
- · Replies 2 ·
High School Do Gravitational Forces Increase for Objects Moving at Light Speed?
- Pratyeka
- · Replies 16 ·
High School Gravity waves and Planck's constant
- Leonard Begy
- · Replies 2 ·
High School Speed of reflected light from moving mirrors in Einstein's train
- zasvitim
- · Replies 38 ·
High School Does Gravitation Start at Black Hole Event Horizon?
- Shaw
- · Replies 9 ·
Graduate Bekenstein-Hawking entropy from Over Cross Oscillation and information recovery
- sufive
- · Replies 6 ·
Undergrad Numerical Solution of Complex Systems in GR
- epovo
- · Replies 5 ·
Undergrad Sabine Hossenfelder says time dilation is due to acceleration
- Epic Mythology
- · Replies 47 ·
Undergrad What is the velocity of a photon through the four dimensions?
- Epic Mythology
- · Replies 9 ·
Undergrad Can two black holes' spacetime curvatures cancel to let you escape?
- Aerodyn
- · Replies 2 ·
Graduate Why can't we say that photon has very very small mass?
- Pradyuman
- · Replies 13 ·
Graduate Why does the conformal diagram of Minkowski spacetime show a timelike boundary?
- Demystifier
- · Replies 23 ·
Graduate GW Binary Merger: Riemann Tensor in Source & TT-Gauge
- MrFlanders
- · Replies 4 ·
Graduate Converting CTC metrics to cylindrical coordinates
- YRC
- · Replies 5 ·
High School Observable universe from a spacecraft at 0.999c
- IroAppe
- · Replies 36 ·
High School The synchronization of clocks and the relativity of motion
- AlMetis
- · Replies 84 ·
Undergrad Why do both astronauts see each other's clock running slow?
- SaintRodriguez
- · Replies 6 ·
Undergrad Is a worldline a curve or a trajectory?
- SaintRodriguez
- · Replies 10 ·
High School How do fields retain their uniformity with interposing objects?
- Clueless123
- · Replies 4 ·
High School How can particles inside black holes move if gravity increases towards the singularity?
- Clueless123
- · Replies 22 ·
High School Four Velocity Sign of Time: \dot t>0?
- Onyx
- · Replies 3 ·
Graduate Hyperplanes of Simultaneity and BigBang
- lektroon
- · Replies 27 ·
Undergrad Universe Expansion: GR vs Hubble Reconciled
- jeremyfiennes
- · Replies 5 ·
High School Is Time Dilation About Particle Motion Rather Than Time Itself?
- teacher94
- · Replies 53 ·
Graduate Solving Geodesics with Metric $$ds^2$$
- edoofir
- · Replies 10 ·
Undergrad Can worldlines exist that defy traditional spacetime classifications?
- SaintRodriguez
- · Replies 18 ·
High School Fast radio burst detected near gravitational wave event
- jedishrfu
- · Replies 4 ·
Undergrad Black holes to explode due to evaporation?
- HansH
- · Replies 57 ·
Undergrad Do objects gain mass while approaching light speed?
- LightningInAJar
- · Replies 25 ·
Insights Why There Are Maximum Mass Limits for Compact Objects
- PeterDonis
- · Replies 3 ·
Undergrad How does the Kerr parameter change as a Kerr black hole evaporates?
- snorkack
- · Replies 3 ·
High School Can we distinguish between redshift, space contraction, and frequency change?
- doudou
- · Replies 4 ·
High School Is Einstein's Space-Time Theory Overfitted or Simply a Visualization Tool?
- lukephysics
- · Replies 29 ·
High School The Effect of Binding Energy on Mass
- Dileep Ramisetty
- · Replies 5 ·
Undergrad Observed Redshift from Moving Source: Deriving the Result
- ergospherical
- · Replies 5 ·
Undergrad Gravitational Field Transformations Under Boosted Velocity
- Sciencemaster
- · Replies 14 ·
Undergrad Light-Like Separation: Is It Possible?
- novice_hack
- · Replies 4 ·
High School Can the Lense-Thirring effect explain galaxy rotation curves?
- Sagittarius A-Star
- · Replies 22 ·
Undergrad How to obtain other inverse metrics than that of Schwarzschild?
- Bishal Banjara
- · Replies 50 ·
High School Block universe theory question
- frankrabbit
- · Replies 53 ·
Undergrad Can the one-way speed of light be measured?
- OscarCP
- · Replies 45 ·
High School Spagettification and a singularity
- HansH
- · Replies 167 ·
High School The twin paradox and black holes
- BoraxZ
- · Replies 31 ·
Undergrad Dark Energy Strength in Great Voids of Galaxies
- Herbascious J
- · Replies 7 ·
Graduate Solving "const. K" in Gourgoulhon's SR in General Frames
- Frank Wappler
- · Replies 4 ·
High School Questions on the Michelson Morley Experiment
- OneAverageGuy
- · Replies 47 ·
Undergrad Gravitational Field Existence in Void: Philosophical Inquiry
- Herbascious J
- · Replies 1 ·
Graduate How Does Linear Framedragging Affect Parallel Moving Masses in Flat Spacetime?
- BoraxZ
- · Replies 11 ·
Undergrad How meaningful is the relativity of simultaneity at large distances?
- EclogiteFacies
- · Replies 12 ·
High School Phase change in light signal reflections between moving rods
- AlMetis
- · Replies 31 ·
High School Why Don't We Live Inside a Black Hole?
- Narasoma
- · Replies 3 ·
Undergrad Circular Orbit in Schwarzschild: Orbital Period
- epovo
- · Replies 5 ·
Undergrad Poincaré symmetries in spacetimes without symmetries
- Suekdccia
- · Replies 7 ·
Graduate Understanding killing vectors and transformations of metric
- dwd40physics
- · Replies 45 ·
High School Is Brian or Jim Wrong? (the science of Dr. Who)
- AtoMick-u235
- · Replies 10 ·
High School Mick's Spooky Time Dilation Puzzle
- AtoMick-u235
- · Replies 3 ·
Graduate Landau's Maximum Mass Limit Derivation in Shapiro & Teukolsky (1983)
- PeterDonis
- · Replies 22 ·
Graduate Motivation for Theta = Pi/2 on Wald GR p138
- strangerep
- · Replies 5 ·
Undergrad Why does the second-order Taylor approximation give a parabola instead of a hyperbola?
- Ramanathan k s
- · Replies 8 ·
Undergrad Can Crafts Reach 2c Relative to Me?
- Abbott287287
- · Replies 3 ·
High School What limits the speed of a gravitational wave to c?
- Rochelobe
- · Replies 13 ·
High School Do A and B observe mirror-image light paths when a source between them emits a flash?
- AlMetis
- · Replies 143 ·
High School Mechanics behind curved time causing gravitation/geodesics
- tachi158
- · Replies 27 ·
High School Speed of light and this Accelerating Rocket scenario
- John SpaceY
- · Replies 45 ·
Undergrad No Symmetry Spacetimes/Metrics in Theory of Relativity
- Suekdccia
- · Replies 7 ·
Undergrad Twin paradox: does continuous circular acceleration slow aging more?
- vibhuav
- · Replies 13 ·
High School Cherenkov Radiation -- How does this not break causality?
- peanutaxis
- · Replies 21 ·
Undergrad Derivation of SR's time-dilatation in 1d?
- Pony
- · Replies 60 ·
Undergrad What Is the Geometrical Meaning of Principal Null Directions?
- Umaxo
- · Replies 3 ·
Graduate Proper Volume on Constant Hypersurface in Alcubierre Metric
- Onyx
- · Replies 7 ·
High School Where does the energy of gravity come from?
- lordoftheselands
- · Replies 73 ·
Undergrad Transforming Schwarzschild to Cartesian coordinates
- epovo
- · Replies 18 ·
Undergrad Differentiate w/ Respect to Affine Parameter
- Haorong Wu
- · Replies 10 ·
Undergrad Understanding Einstein's second postulate of special relativity
- Erland
- · Replies 57 ·
High School Calculating Fuel Efficiency of Rocket Going Near c
- Peter564
- · Replies 2 ·
Undergrad Pole vaulter at relativistic speed reaches door before button opens
- Jrs580
- · Replies 27 ·
Undergrad Asymmetry between Galilean and Lorentz transformations
- Chenkel
- · Replies 13 ·
Undergrad Is spacetime a vector space under Galilean relativity?
- Saw
- · Replies 146 ·
Undergrad Mainstream interpretation of Newton's bucket argument?
- wisdom
- · Replies 12 ·
Undergrad Can causally disconnected events inside a black hole affect the outside universe?
- Feynstein100
- · Replies 21 ·