Left-right arrow in Einstein equation

Context: Undergrad
Thread starter etotheipi
Start date Apr 3, 2021
Tags

Einstein Einstein equation

Join the discussion

Registration is free. Ask a follow-up in this thread, or start your own.

2 replies · 2K views

etotheipi

Thread starter
Apr 3, 2021

Short, probably stupid, question; what does this left-right arrow ##a \leftrightarrow b## at the bottom-right mean? [It's this paper for ref.]

Does it just mean the last term repeated, except this time with ##a## and ##b## indices exchanged? Thanks.

Discussion

Physics news on Phys.org

Theoretical framework expands directional light control beyond ordered crystal structures
Copper's surprising melting behavior provides insights into future fusion design
Melting diamond could unlock triple fusion gain and the secrets of ice giant planets

anuttarasammyak

Homework Helper

Gold Member

Apr 3, 2021

LHS is symmetric as for a nd b so RHS is also. So your thought seems reasonable.

Demystifier

Science Advisor

Insights Author

Apr 10, 2021

Why is this thread on the Last week's most popular topics list?

Left-right arrow in Einstein equation

Discussion

Undergrad Why is gravity a fictitious force?

Undergrad Why is 0.9g more efficient than 1.5g to Tau Ceti in Project Hail Mary?

Undergrad KE of rotating disc

Graduate How valid is the Block Universe theory?

Undergrad Why is the Lorentz Force always perpendicular to velocity?

Undergrad An alternative derivation of the equation of motion in General Relativity

Undergrad Is the weak field limit valid for the Brans-Dicke scalar field?

Graduate Energy-to-angular momentum ratio in EM v. gravity quadrupole radiation

Graduate How to show spin ##= \pm 2/\omega## for a circ-polarized gravity wave

Insights Revisiting the Velocity-Time Function

Insights Remote Operated Gate Control System

Insights AI Enriched Problem Solving

Insights Thinking Outside The Box Versus Knowing What’s In The Box

Insights Why Entangled Photon-Polarization Qubits Violate Bell’s Inequality

Insights Quantum Entanglement is a Kinematic Fact, not a Dynamical Effect

Left-right arrow in Einstein equation

Discussion

Similar threads

High School Which term of the Einstein equation is larger?

Undergrad Is the sign of the Einstein equation right in Chandrasekhar's Black holes?

Undergrad Solving the Spherically Symmetric Einstein Equation

Undergrad Deriving Einstein Equations: Questions on Linearity & Symmetry

Graduate Why aren't other Einstein equation components derived in the Newtonian limit?

Undergrad Is the Einstein equation E=Mc^2 correct?

Graduate Einstein equation and particle jets

Finding exact plane wave solution from Einstein equation constraint

Graduate Curvature and Stress-Energy: Solving the Einstein Equation with Tensor Densities

Graduate Understanding Wald's Book: Appendix E and the Einstein Equation