The Ultimate Stiffness Limit of Neutron Stars ⚡ экспресс
The center of the most massive neutron star is squeezed tighter than anything else in the Universe. Scientists have figured out just how much matter can be compressed before the star collapses. It turns out that pressure cannot exceed 38.5% of the energy density — it's like a spring compressed almost to its limit, but not quite. Curious, what would happen if you added just a tiny bit more?
Just as in a crowded room each new person sharply increases the pressure on the walls, in a neutron star increasing density leads to a rise in internal resistance. But even this resistance has an absolute ceiling. Physicists describe it with the ratio of pressure to energy density (the quantity φ) — a sort of measure of matter's "stubbornness." From special relativity, φ cannot exceed 1 anyway (otherwise signals inside the star would outpace the speed of light). And general relativity, adding spacetime curvature, tightens the limit even further. The key ingredient is the stability condition: the star's mass must increase from center to edge without gaps. With it, φ does not exceed 0.385. This number works for any conceivable star filling, from ordinary neutrons to quark soup. Surprisingly, the same law applies to water in a glass — it's just realized at negligible fractions of a percent, so we don't feel it.
🎯 A teaspoon of neutron star material weighs as much as Mount Everest.