General-Relativity | Sebastian Spicker

2026

1 article

15 Jan 2026 Try to Relax — and Other Things That Prevent Themselves “Try to relax” can recruit the monitoring that keeps tension salient. Traversable wormholes face a very different constraint: sustaining their geometry requires stress-energy that violates classical energy conditions. The comparison is an analogy about constraints, not one mechanism shared by psychology and spacetime. physicsgeneral-relativitywormholes

2023

1 article

7 Jul 2023 The Milky Way Is a Gravitational Wave Detector LIGO uses 4-kilometre laser arms to detect gravitational waves at hundreds of hertz. Pulsar timing arrays use millisecond pulsars scattered across the Milky Way — arms measured in light-years — to detect gravitational waves at nanohertz frequencies, ten orders of magnitude lower. In June 2023, four collaboration papers reported evidence for a stochastic gravitational wave background. The Milky Way itself was the detector. gravitational-wavesastronomypulsars

2022

1 article

17 Oct 2022 What Black Hole Images Actually Show (and Why a Wormhole Would Look Different) The EHT images of M87* and Sgr A* are remarkable not because they surprised us, but because they confirmed a century-old prediction at microarcsecond precision. The more interesting question: what would a wormhole look like? Completely different — and we have never seen that. astrophysicsblack-holesgeneral-relativity