Where Physics Starts SweatingField reports from the edge of known physics: neutron stars, black holes, dark matter, and the places where our best theories still fail.https://physics.nixfred.com/en-usWhy We Can't Measure Gravity Inside a Neutron Starhttps://physics.nixfred.com/articles/01-gravity-inside-neutron-star/https://physics.nixfred.com/articles/01-gravity-inside-neutron-star/Neutron star interiors are inferred indirectly from pulsar timing, X-ray measurements, binary systems, and gravitational waves. The exact interior gravitational profile depends on the equation of state of ultra-dense matter, which remains uncertain.Thu, 28 May 2026 00:00:00 GMTneutron starsgravityequation of stategeneral relativityThe Most Misnamed Object in the Universehttps://physics.nixfred.com/articles/02-most-misnamed-object/https://physics.nixfred.com/articles/02-most-misnamed-object/Despite the name, neutron star cores may contain layers where matter changes form, including superfluid neutrons, hyperons, deconfined quarks, or other exotic phases, depending on the true equation of state.Thu, 28 May 2026 00:00:00 GMTneutron starsquark matterhyperonsQCDThe Star That Makes Time Run Slowhttps://physics.nixfred.com/articles/03-star-that-makes-time-run-slow/https://physics.nixfred.com/articles/03-star-that-makes-time-run-slow/General relativity predicts gravitational time dilation. Clocks deeper in a gravitational field tick more slowly relative to distant observers. Neutron stars create extreme gravitational fields, making relativistic effects essential rather than negligible.Thu, 28 May 2026 00:00:00 GMTtime dilationgeneral relativityneutron starsThe Matter We Have Never Seenhttps://physics.nixfred.com/articles/04-matter-we-have-never-seen/https://physics.nixfred.com/articles/04-matter-we-have-never-seen/Most of the matter in the universe appears to be invisible. We infer dark matter from galaxy rotation curves, gravitational lensing, galaxy cluster dynamics, and the cosmic microwave background, but its fundamental nature remains unknown.Thu, 28 May 2026 00:00:00 GMTdark mattercosmologygravitygalaxy rotationThe Missing Objects Between Stars and Black Holeshttps://physics.nixfred.com/articles/05-missing-objects-mass-gap/https://physics.nixfred.com/articles/05-missing-objects-mass-gap/The compact-object mass gap refers to uncertainty or scarcity in observed objects between the heaviest neutron stars and the lightest black holes. Ongoing gravitational-wave detections continue to refine this picture.Thu, 28 May 2026 00:00:00 GMTmass gapblack holesgravitational wavescompact objects