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 Simultaneity agreeing in different frames
- DAC
- · Replies 13 ·
Graduate Why does special relativity fail where general relativity is needed?
- kaushikquanta
- · Replies 10 ·
Undergrad Understanding Light Clock Confusion on Moving Trains - A Discussion
- DAC
- · Replies 44 ·
Graduate The Infalling Traveler's Perspective on Time and Mass in a Black Hole
- zylon
- · Replies 14 ·
Graduate Particle in Minkowski Space: Motion in a Flat Universe
- adsquestion
- · Replies 4 ·
Graduate Time Dilation and different clock types
- DAC
- · Replies 56 ·
Graduate Rotation in special relativity
- klen
- · Replies 15 ·
Graduate Why doesn't a ball roll off a moving platform in a relativistic frame?
- Pelion
- · Replies 4 ·
Graduate Time, spacelike foliations and timelike vector fields in GR
- ShayanJ
- · Replies 7 ·
Graduate Is "now" relative or absolute?
- Lombasto
- · Replies 14 ·
Graduate Gravitational Fields: Same or Different?
- Shaw
- · Replies 6 ·
Undergrad Why unify gravity with other forces if it's fictitious
- Iheartscience
- · Replies 23 ·
Graduate Space-Time Curvature in General Relativity
- klen
- · Replies 9 ·
Graduate Deriving 8πG/c^4 in General Relativity
- shounakbhatta
- · Replies 1 ·
Graduate Momentarily co-moving inertial frames
- Geofleur
- · Replies 7 ·
Graduate Does Length Contraction affect measured velocity?
- taylorules
- · Replies 7 ·
High School Inertial Frames of Reference - Understanding Special Relativity for 11-Year-Olds
- Mahdi Al Sabad
- · Replies 8 ·
Graduate Does mass or gravity curve spacetime and bend light?
- Dukon
- · Replies 22 ·
High School How Does Michelson-Morley Interferometer Measure Space-Time?
- Alex299792458
- · Replies 1 ·
Undergrad Does traveling near light speed shorten a 20 AU path through length contraction?
- EbolaHost
- · Replies 1 ·
Graduate Creating Mass w/ Velocity: Effects on EM Wave?
- marlowgs
- · Replies 5 ·
Graduate Can faster-than-light travel reverse event ordering between distant observers?
- JohnnyGui
- · Replies 19 ·
Graduate Derivation of Kirchhoff's Formula in Gravitational Radiation
- jstrunk
- · Replies 10 ·
Graduate Did Synge's world function concept influence modern relativity literature?
- facenian
- · Replies 3 ·
Undergrad Can we say Earth orbits the sun if the origin can be placed anywhere?
- houlahound
- · Replies 22 ·
Graduate Are spatial and temporal dimensions interchangeable?
- R. E. Nettleton
- · Replies 7 ·
High School Could Everything on Earth Float Without Spacetime?
- George Akba
- · Replies 42 ·
Graduate How does gravity affect the path of light?
- Ron777
- · Replies 4 ·
Undergrad Gravitational Time Dilation: A Layman's Explanation
- Hihello
- · Replies 5 ·
Undergrad What does Purcell actually say about electromagnetism and relativity?
- bcrowell
- · Replies 32 ·
Graduate SR as Geometrical Constructions
- bcrowell
- · Replies 5 ·
High School Do black holes make the universe appear to expand away from the observer?
- Joe_Limon
- · Replies 6 ·
Graduate What is the difference between standard and isotropic metrics?
- Emilie.Jung
- · Replies 9 ·
Graduate Cosmological constant times the metric tensor
- Isaac0427
- · Replies 12 ·
Graduate Is the equivalence principle related to the principle of relativity?
- Hihello
- · Replies 2 ·
Graduate Do event horizons have an inside, or just a frozen shell of energy?
- Alicowie
- · Replies 2 ·
Undergrad SR Proves Eternalism: Is It Physically Substantial?
- guygerst
- · Replies 5 ·
Graduate Can You Truly Achieve No Motion in Space?
- AlanC
- · Replies 18 ·
Graduate Derivation from Landau and Liffshitz, vol 6
- Geofleur
- · Replies 21 ·
Graduate Are Gravitational Waves Lossy?
- Grinkle
- · Replies 5 ·
Graduate Alternative definitions of geodesic
- bcrowell
- · Replies 45 ·
Graduate Covariant fields and new physics
- giulio_hep
- · Replies 5 ·
High School Is time dilation just a problem with our clocks?
- Edriven
- · Replies 84 ·
Graduate What is a gravity wave detector measuring?
- Grinkle
- · Replies 5 ·
Graduate Is the center of mass fixed in Relativity?
- fast_squirrel
- · Replies 9 ·
Undergrad What is the Principle of Equivalence and how was it determined?
- Emilie.Jung
- · Replies 76 ·
High School Where are the known stellar black holes and what are their properties?
- DarioC
- · Replies 2 ·
Graduate Why doesn't the vertical light beam get out of a black hole?
- John Duffield
- · Replies 41 ·
Graduate Does gravity expand space or just curve it in all dimensions?
- pforeman
- · Replies 1 ·
Graduate Using Light as a absolute frame of reference?
- FrancisClinton
- · Replies 55 ·
Graduate Why does a reflecting photon show time dilation but other particles don't?
- Aniket1
- · Replies 19 ·
Graduate Einstein-Hilbert action origin
- Emilie.Jung
- · Replies 18 ·
Graduate Einstein's synchronous clocks in § 2 of relativity paper
- bahamagreen
- · Replies 10 ·
Graduate How to prove that something is a non-curvature singularity?
- bcrowell
- · Replies 23 ·
Graduate Understanding Invariance of Spacetime Intervals
- nomadreid
- · Replies 2 ·
Graduate What tidal effects would a person feel falling through Earth's center?
- Adrian F
- · Replies 11 ·
Graduate What Would Happen if 2 People Were 1 Light Hour Apart?
- Paras Patel
- · Replies 2 ·
Graduate Where does the four-momentum concept come from in special relativity?
- Sobhan
- · Replies 6 ·
Graduate What's the 3d equation of the Alcubierre warp?
- Teslanumber1
- · Replies 8 ·
Graduate What is the relativity of simultaneity measuring?
- DAC
- · Replies 20 ·
Graduate Traversable wormhole without negative energy (paper)
- MTd2
- · Replies 10 ·
Who discovered the concept of time
- DAC
- · Replies 12 ·
Graduate 4 velocity in Schwarzchild metric
- Big Guy
- · Replies 11 ·
Graduate Why don't my two formulas for force in relativistic motion match?
- greswd
- · Replies 2 ·
Undergrad Relative Time in Space: What Speed for 1 Day Equals 1 Day on Earth?
- mileymo
- · Replies 9 ·
Graduate Twin paradox: how can Jim reach Alkaid in 7.92 years Earth time?
- aliens123
- · Replies 30 ·
Graduate Time Dilation by Light Alone? A Software Engineer's Exploration
- stringpoet
- · Replies 13 ·
Graduate Observing the event horizon of a black hole
- Peter953
- · Replies 6 ·
Graduate Inertial observers explanation for unruh thermalization
- T S Bailey
- · Replies 9 ·
Graduate Muons hitting Earth half-life explanation in SR
- loislane
- · Replies 12 ·
Graduate Why does a photon move through space and time on Minkowski diagrams?
- DiracPool
- · Replies 5 ·
Graduate How long and far to accelerate a spaceship to light speed and back?
- mileymo
- · Replies 3 ·
Undergrad Why is the Constant in Mass-Energy Equivalence C^2?
- Manel
- · Replies 7 ·
Graduate Do gravitational waves propogate slower when blocked by mass
- NotJimmy
- · Replies 5 ·
Graduate Does time dilation relate to differences in entropy rates?
- newjerseyrunner
- · Replies 5 ·
Graduate Why does a black hole appear to accelerate after the towing mass detaches?
- jartsa
- · Replies 8 ·
Graduate Does acceleration curve spacetime?
- DaniV
- · Replies 10 ·
Graduate Is Gravity Really the Weakest Force in the Universe?
- FredrikJ
- · Replies 5 ·
Undergrad Why does a black hole get bigger when it consumes mass?
- Mark Lees
- · Replies 10 ·
Graduate Problem with Purcell's model of electromagnetism
- John Duffield
- · Replies 24 ·
Graduate Why does the traveling twin age less if all reference frames are equal?
- Heatherfield
- · Replies 16 ·
Insights Time Dilation and Redshift for a Static Black Hole - Comments
- stevebd1
- · Replies 42 ·
Graduate Gravity, Time Dilation & Black Holes: Q&A
- mileymo
- · Replies 4 ·
Graduate Redshift effect And photon energy loss
- ujellytek
- · Replies 3 ·
Graduate Proving Non-linear Wave Equation for Riemann Tensor
- dman12
- · Replies 3 ·
Graduate Barut's Electrodynamics Identity Problem
- facenian
- · Replies 17 ·
High School Electromagnets are a relativistic phenom?
- DaveC426913
- · Replies 47 ·
Graduate Very precise Michelson-Morley experiments
- wmikewells
- · Replies 22 ·
Undergrad What is the 2D Concept of Spacetime and How Does It Work?
- Dimitri655
- · Replies 20 ·
Graduate What is the interpretation of a Misner string in Bonnor's theory?
- bcrowell
- · Replies 6 ·
Undergrad Struggling with the Special Relativity and simultaneity
- Ut-Napishtim
- · Replies 60 ·
Graduate Why must a length-preserving rotation matrix be orthogonal?
- brotherbobby
- · Replies 5 ·
Graduate How long does constant acceleration near lightspeed last?
- wondercosmos
- · Replies 3 ·
Undergrad Does time depend on speed; or on velocity?
- Shafat Hasan
- · Replies 8 ·
Graduate Calculating Total Time Dilation in a Falling Photon Experiment
- Josh3to107
- · Replies 7 ·
Graduate Space-Time Curvature: Evidence of Mass Effect?
- Muhammad Sabih
- · Replies 6 ·
Undergrad Why is time not simply a measure of energy's change in position?
- Maxila
- · Replies 28 ·
Graduate Gravity's Effects on Light: Why Light Doesn't Always Follow a Straight Line
- Muhammad Sabih
- · Replies 2 ·
Graduate Orientability of Null Submanifold w/ Boundary - Stokes' Theorem
- ifidamas
- · Replies 2 ·
Undergrad Why is special relativity a local phenomenon?
- sunrah
- · Replies 7 ·