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 What is the structure of a photon and can it be observed?
- just curious
- · Replies 7 ·
Graduate What does a falling observer see at a black hole event horizon?
- Grogbor
- · Replies 8 ·
Graduate Singularity Theorems: An Accessible Reference
- jinawee
- · Replies 3 ·
Graduate Does temperature in special relativity depend on the frame of observation?
- Ravyan Asro
- · Replies 8 ·
Graduate Time dilation traveling 100 light-years at relativistic speeds
- Saerryan89
- · Replies 4 ·
High School Deriving GR without EFE: Could it be this Simple?
- grav-universe
- · Replies 1 ·
Graduate Observer Falling Into a Black Hole -- What do they see?
- valentin mano
- · Replies 16 ·
Graduate Faster Than Light Communication Through Space-Time Bubbles
- Teslanumber1
- · Replies 2 ·
Graduate Ergosphere and angular velocity
- Neutrinos02
- · Replies 20 ·
Graduate Proof than an equation is Lorentz invariant
- spaghetti3451
- · Replies 8 ·
Undergrad Does relativity say gravity is space pushing us toward Earth?
- CollinsArg
- · Replies 3 ·
Graduate Conservation laws with Killing fields
- Neutrinos02
- · Replies 19 ·
Graduate Does E in E=mc^2 Include Gravity?
- Pjpic
- · Replies 1 ·
Graduate Relativistic Lagrangian and Hamiltonian for a free particle
- dyn
- · Replies 7 ·
Graduate Time Distortion at High Altitudes: Is Now Still Now?
- butchie
- · Replies 4 ·
Graduate Observer dependent event horizon for Schwarzschild black hole
- nilsgeiger
- · Replies 21 ·
Graduate Action and reaction when fast object is pushed
- jartsa
- · Replies 5 ·
Graduate Signal time in Twin Paradox: Fast clocks? Redshift/blueshift
- EliteTeamKiller
- · Replies 3 ·
Graduate Integration by parts in curved space time
- naima
- · Replies 13 ·
Graduate Curvature singularity with well-behaved Kretschmann scalar
- bcrowell
- · Replies 22 ·
Graduate Fun with Carminati-McLenaghan invariants
- bcrowell
- · Replies 2 ·
Graduate Can electron be considered a Source of gravitational field?
- big_bounce
- · Replies 7 ·
Undergrad Faster than the speed of light?
- DonB
- · Replies 28 ·
Graduate What time dilation do muon observers experience?
- DAC
- · Replies 7 ·
Undergrad Twin Paradox: Relation between Age and Speed of light .
- Aero_Arnendu
- · Replies 2 ·
Graduate Kinetic energy of a spinning body
- lightarrow
- · Replies 24 ·
Undergrad Does continuous acceleration eventually create a black hole
- ddesaneis
- · Replies 6 ·
Graduate Local Inertial Frame in General Relativity - Neutrino
- Neutrinos02
- · Replies 16 ·
Graduate LISA Pathfinder Launch on Dec 2: Einstein's Last Theory
- bcrowell
- · Replies 1 ·
Graduate Uniformly accelerating frame of reference
- sweet springs
- · Replies 42 ·
Graduate Calculate Time Dilation for Space Travel w/ Formula
- DET
- · Replies 10 ·
Graduate Time Dilation: Rel. Ref. Frames and Universal Reference Frame
- Big L
- · Replies 7 ·
Graduate Curvature polynomials vanish for plane waves?
- bcrowell
- · Replies 10 ·
Graduate How did Einstein know speed of gravity?
- bluemoonKY
- · Replies 10 ·
High School Does time dilation occur at speeds below light speed?
- iForget
- · Replies 6 ·
Undergrad Should teaching special relativity skip time dilation and length contraction?
- m4r35n357
- · Replies 125 ·
High School Inside the Moving Truck: A Fly's Dilemma
- rakshit1992
- · Replies 3 ·
Undergrad Basic Questions on Time Dilation Implications
- DonB
- · Replies 10 ·
Undergrad Why Is the Proportionality Constant in E=mc² Just c²?
- clinden
- · Replies 15 ·
Graduate Is there a term for distance divided by proper time in relativistic travel?
- Smattering
- · Replies 13 ·
Graduate Speed of an object in a rotating frame
- JVNY
- · Replies 34 ·
Graduate Relativistic Euler Equation in Spherical Coordinates
- Geofleur
- · Replies 3 ·
Graduate Twins flying at the speed of light in opposite directions
- kinimod
- · Replies 68 ·
Graduate Could you express GR in terms of a density of spacetime?
- Dale
- · Replies 23 ·
Graduate Warp drives and event horizons
- gpk
- · Replies 18 ·
Insights The Block Universe - Refuting a Common Argument - Comments
- PeterDonis
- · Replies 146 ·
Graduate Relativistic momentum (Lorentz boost) low velocity limit
- Neutrinos02
- · Replies 1 ·
Graduate Metric in polar coordinate derivation
- DiracPool
- · Replies 2 ·
Undergrad Invariance of Acceleration in Inertial Reference Frames
- 0pt618
- · Replies 11 ·
Graduate Abrahams-Minkowskii Controversy: Is Phonon Momentum Defined?
- pervect
- · Replies 1 ·
Graduate Could Time Be Warped Alongside Space in Sci-Fi Travel Scenarios?
- Ervin
- · Replies 4 ·
Graduate Relativistic Particle Decay: Momentum Conservation
- whatisreality
- · Replies 3 ·
Graduate Advantage/disadvantage of notation
- grzz
- · Replies 4 ·
Graduate Suggested Reading on Newtonian vs Relativity?
- 24forChromium
- · Replies 2 ·
Graduate Humans Move Before Becoming Black Hole
- Ted Baas
- · Replies 2 ·
Graduate Contracting Riemann tensor with itself
- ShayanJ
- · Replies 2 ·
Graduate Color of light in the Light Clock
- SlowThinker
- · Replies 19 ·
Graduate Faster than light - under what circumstances?
- pixel
- · Replies 14 ·
Graduate What can be said about S-T global properties from the EFE?
- loislane
- · Replies 5 ·
Graduate Trans-Planckian Problem for Black Holes: Do Infalling Particles Become BHs?
- T S Bailey
- · Replies 5 ·
Graduate Conservation of angular momentum and RoS
- SlowThinker
- · Replies 82 ·
Graduate Expressing affine connection in tetrad formalism
- lapo
- · Replies 2 ·
High School How does GR explain increase/decrease in speed?
- Jakaha
- · Replies 67 ·
Graduate Why isn't length contraction permanent even though time dilation is?
- Ganesh Ujwal
- · Replies 21 ·
Graduate What Led Einstein to Connect Light and the Speed of C to E?
- halpmaine
- · Replies 6 ·
Graduate Why does the train observer see the right lightning first in Einstein's train experiment?
- GhostLoveScore
- · Replies 66 ·
Graduate Accelerated expansion and perceived gravity
- sickwayne
- · Replies 6 ·
Graduate Karl Schwarzschild's 100th Anniversary: No BH Event Horizon
- StateOfTheEqn
- · Replies 3 ·
Graduate Invariance: What Does it Mean?
- B3NR4Y
- · Replies 5 ·
Graduate Relation between affine connection and covariant derivative
- nilsgeiger
- · Replies 2 ·
Graduate Singularity of spacetime/singularity of the riemanian tensor
- Neutrinos02
- · Replies 5 ·
Undergrad Twin's Paradox: Who is Older A or B?
- yykcw
- · Replies 8 ·
Graduate Why can't light return from a black hole?
- Dephenistrator2
- · Replies 7 ·
Graduate Universe Hubble radius equal to Schwarzschild radius
- Gerinski
- · Replies 64 ·
Graduate Christoffel symbols derivation
- PWiz
- · Replies 5 ·
Graduate Gravitational Waves: What Happens to a Body Experiencing One?
- CassiopeiaA
- · Replies 1 ·
Graduate Einstein-Cartan Theory: Dynamical Definition of Spin Tensor
- lapo
- · Replies 1 ·
Graduate Why can metric tensor components be manipulated like numbers?
- dumbperson
- · Replies 11 ·
Graduate How does GR explain twist at the poles
- CRT
- · Replies 6 ·
Graduate Do non-black hole singularities have observable properties?
- bcrowell
- · Replies 17 ·
High School Why does light have mass if it has zero rest mass?
- SrayD
- · Replies 7 ·
High School On light clocks and reference frames
- Raymond Potvin
- · Replies 62 ·
Graduate Do black hole singularities have zero volume?
- Invutil
- · Replies 4 ·
Graduate Understanding Asymptotes in Rindler Space - Physics Forums
- DiracPool
- · Replies 7 ·
Undergrad What is the Effect of Gravity on Einstein's Train in Special Relativity?
- SlowThinker
- · Replies 219 ·
Graduate What Happens to Wave Measurements When You Sail at the Speed of Light?
- Gaz
- · Replies 3 ·
Undergrad Visual Effects of Special Relativity
- vJames
- · Replies 9 ·
Graduate Conservation of 3-Momentum & Energy in RoS
- greswd
- · Replies 16 ·
High School Why does light have a finite speed and limit all velocities?
- VECT
- · Replies 27 ·
Graduate Why is Schwarzschild singularity not real
- Blackholeinside
- · Replies 13 ·
Graduate Time dilation at the event horizon of a black hole
- Smattering
- · Replies 16 ·
High School How does time dilation appear to a third observer?
- SuperfundMatt
- · Replies 1 ·
Undergrad Is Einstein's warped time the same as gravitational time dilation?
- klen
- · Replies 15 ·
Undergrad Gravitational Field: What Would Happen?
- LeoPedranjo
- · Replies 8 ·
Graduate Why Do We Feel Acceleration If Gravity Is Just Curvature of Space-Time?
- psuedoben
- · Replies 4 ·
Graduate Confusion in General Relativity
- klen
- · Replies 51 ·
Graduate Transitioning from Finite to Infinite Mass in a Black Hole
- Cody Richeson
- · Replies 6 ·
Graduate Can you walk faster than light inside a spacecraft traveling at c?
- abcjake
- · Replies 8 ·
Undergrad Do black holes have internal space where matter can move freely?
- Invutil
- · Replies 4 ·
Graduate Gravitational Lenses: Does Gravity Distort Spacetime?
- FyzikBlbosti
- · Replies 2 ·