How Earthly Atomic Nuclei Reveal the Size of Neutron Stars ⚡ экспресс
Neutron stars are among the most mysterious objects in the cosmos, but studying them directly is difficult. It turns out that their sizes can be determined by experiments on ordinary atomic nuclei here on Earth. A new formula links how nuclei respond to an electric field to how tightly packed a neutron star is. In this way, Earth-based laboratories unlock the secrets of unimaginably distant worlds.
A neutron star is the ultra-dense remnant of a supernova explosion, whose existence was predicted by Fritz Zwicky back in the 1930s. Later, Jocelyn Bell Burnell detected them as pulsars — rotating sources of strictly periodic radio signals.
The precise radius of a neutron star depends on the stiffness of nuclear matter — its ability to resist compression. This quantity can’t be measured directly for the star, but it can be calculated in the lab. The atomic nucleus is like a sponge: squeeze it, and its compressibility tells you how soft the star-sphere is in distant space. Chandrasekhar laid the groundwork for such a connection; recent work found a universal rule that equates the behavior of protons and neutrons in a nucleus to the properties of stellar matter — and all this fits within the standard model.
Measurements on lead nuclei showed: if the star weighs as much as 1.4 Suns, its radius is roughly 12 kilometers. The tiniest change in the nucleus's deformability shifts this estimate by kilometers. So, by squeezing a tiny sample in an earthly lab, physicists refine the size of an object thousands of light-years away. The cosmos and the microcosmos have come together not in fiction, but in precise calculation.
🎯 Due to the monstrous gravity of a neutron star, its surface is almost perfectly smooth: mountains there can't be taller than a few millimeters — any bump gets instantly crushed.
🎬 In the sci-fi novel 'Dragon's Egg', a civilization is described living on a neutron star, where time flows thousands of times faster than on Earth.