The mystery of the supercomputer crack open neutron star

Inside the most extreme objects in the universe, the behavior of matter causes Einstein’s head to rotate.

Neutron stars package our sun mass into a sphere 12 miles wide, forming a density so strong that teaspoons weigh 6 billion tons. Now, MIT researchers have used the world’s most powerful supercomputers to stare at these star remnants, revealing secrets about the fundamental forces that manage the universe’s most compressed problems.

Using the Oak Ridge National Laboratory’s border supercomputer (which may exceed the calculations per second), the team maps how stress and density interact in neutron stars in unprecedented conditions. Their findings published in the Physical Review Letter provide the first strict quantum chromosomal dynamics constraints on the equations of the neutron star equations in states, with effects far beyond astrophysics.

When stars become physics lab

When a large star collapses, neutron stars form, squeezing protons and electrons together until they merge into the neutron. The result is contrary to earthly experience: matter is so dense that the nucleus touches, so that conditions cannot be replicated in any laboratory.

“Neutron stars are super dense environments, and we know a few things, but not very big. It’s not a matter we can create in the lab and test, but it’s something we can try to do with theoretical predictions,” said William Detmold, a leading researcher at the project and a professor in the MIT Department of Physics.

The challenge is understanding the equation of state of a neutron star – basically how changes in density or temperature affect internal pressure. This relationship determines key characteristics, such as maximum mass, because neutron stars exist in a constant tug of war between gravity collapse and internal pressure pushing outward.

Quantum chromosome dynamics challenge

At the density of neutron stars, the familiar atomic world disappeared. Instead, matter is composed of quarks and excitants – the basic components dominated by quantum chromosome dynamics (QCD), a theory that describes strong nuclear power. However, the mathematical complexity of QCD makes direct calculations nearly impossible, especially under extreme conditions.

The MIT team used a lattice QCD that maps quarks and vibrations to a four-dimensional spatiotemporal grid. Their computing grids represent some attempts to do such calculations ever, requiring mathematical matrices that reach sizes of 10 billion to 10 billion.

“The key component of these lattice QCD calculations is called quark propagators, which encodes the probability of quarks moving from one place to another. If you write them out as entries in the matrix, the matrix will be 10 to 10 to 10 to 10 to 10 to 10, which is very big,” Detmold explained.

Isospin: Hidden dimensions

The researchers focused on silicin density, a quantum property that distinguishes neutrons from protons. Most ordinary stars have almost equal neutrons and protons, bringing them to a homologous density of near zero. However, as the name suggests, neutron stars mainly contain neutrons, thus producing substantial sibling density, which fundamentally changes the behavior of matter.

“What we basically do in this project is to calculate how changing the homophone density will affect the problem we see. This is the first time that we can plot the change of pressure as you change that density. Now, we do have equations of state mapped across the entire density axis,” DeTmold said.

This ISOSPIN method provides a computational backdoor to understand neutron stars. Although direct calculations involving equal numbers of neutrons and protons encounter insurmountable mathematical obstacles (notorious “marking problem”), the calculations of sibling concentration intensity are still draggable while providing strict boundaries for real neutron star properties.

Extreme superconductivity

At the highest density of the study, the team found evidence of an exotic superconducting state in which the Quark-Antiquark pair formed a Cooper pair, similar to that of superconductivity in Earth’s materials that are more extreme than superconductivity. The calculations show a superconducting gap that matches theoretical predictions but is much higher than previous estimates.

This color superconductivity represents an important stage in one stage that is different from the ground experience. The gap – basically breaking down these Cooper pairs of energy required – provides key insights into the behavior of matter under the most extreme conditions in the universe.

By comparing its lattice QCD results with perturbation calculations that are efficient at ultra-high density, the researchers can extract this gap with unprecedented accuracy, providing the first direct computational evidence for color superconductivity in dense quark matter.

Break the sound barrier

One of the most surprising findings involves the speed of sound in neutron star matter. The team found that sound waves travel faster than the “conformal limit,” a theoretical maximum derived from the assumption of matter, that is, the behavior of matter is like gases without mass particles.

This discovery challenges the basic assumptions about dense matter. For decades, physicists have believed that sound speeds in any strongly interactive system cannot exceed this limit. MIT results show that quantum chromosomal dynamics allow (perhaps required) the invasion of such constraints in dense stellar matter.

The meaning goes beyond neutron stars. If sound can propagate faster in the core of neutron star, similar behavior may occur from the moment after the Big Bang to the collision of heavy nuclei in particle accelerator.

Calculate Olympus

These calculations even pushed Frontier’s extraordinary abilities to its limits. The team spent eight months nearly continuous computing time, producing snapshots of the quark and Gluon configurations before applying the new algorithm to extract the thermodynamic properties.

“In terms of parallel computing power and storage, systems such as Frontier provide a scale that is almost a necessary condition for performing such computing. For example, in terms of computing power and storage.

Abbott’s statement hints at the extraordinary scope of these simulations. “The system we are studying is of course the most particles in any lattice QCD calculation. Most lattice calculations study up to three to four particles, and we are using thousands of particles.”

Innovation that makes it possible

In addition to the original computing power, the team has also developed new algorithmic methods, which greatly improves efficiency. Their key innovations allow researchers to explore different densities using the same basic calculations, rather than starting from scratch each time.

“The new algorithms we developed allow us to analyze them without generating new samples every time,” Detmold noted. “We can basically use the same sample set and change the number we are trying to calculate on them. So we can access the system at different densities and just change the density as much as possible.”

This breakthrough in algorithms not only represents mere computational efficiency, but also opens up entirely new research possibilities by making previously impossible routine access to computations.

Bridge theory and observation

This study provides a crucial theoretical basis for explaining the observation of neutron star probes. Latest gravitational wave detection of neutron star mergers provides new data on these objects, but understanding the meaning of observations requires the theoretical framework provided by this work.

“One of the key questions here is whether there is quark matter inside a neutron star. In fact, the answer says you will never have a neutron star in a detector and test it. So you will have to predict what happens if that or not happens and fight the experiment,” Detmold explained.

The team’s calculations set strict quantum mechanical boundaries on the properties of neutron stars for the first time. These boundaries do not depend on approximate models or phenomenological assumptions, and they emerge directly from the fundamental theories that control strong interactions.

As Detmold reflects, “Science never really involves certainty. You come up with a theory that you can limit it from experiments, but you really learn only what you learn from the data you have. There will always be some ambiguity, and you can really understand something that is ambiguity to really understand the scope of that meaning.

In deferring this ambiguity, these calculations bring us closer to understanding neutron stars and the fundamental nature of matter itself under the most extreme conditions the universe can create.

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