'นอต' นิวเคลียร์อาจคลี่คลายความลึกลับของอะตอม: โครงสร้างที่เรียกว่า skyrmions อาจเอาชนะอุปสรรคในการคำนวณฟิสิกส์อะตอมได้

โครงสร้างคล้ายปมที่เรียกว่า skyrmions อาจช่วยให้นักวิทยาศาสตร์คลี่คลายการทำงานภายในของนิวเคลียสของอะตอมได้, การศึกษาทดแทนแนะนำ. Skyrmion อาจเป็นการรบกวนเล็กน้อยในสสารที่มากเกินไป, รูปแบบการหมุนวนนั้น, ประเภทของปม, is tough to undo. within the Sixties, physicist Tony Skyrme prompt that these structures — since named once him — may represent protons and neutrons inside a nucleus in theoretical calculations. however despite some initial promise, the concept hit snags. โดยเฉพาะ, skyrmion calculations created malformed nuclei.

ALL KNOTTED UP Knotlike structures called skyrmions could help scientists study the nucleus of an atom, such as helium Photo: SPL/SCIENCE

But currently researchers have improved their calculations of however protons and neutrons ought to cluster along within the skyrmion image. Those results in agreement with expectations supported experimental knowledge, the team reports in an exceedingly study in press at Physical Review Letters.

Here’s however the concept works: within a nucleus, particles referred to as pions ar perpetually zinging around, serving to to carry the nucleus along. even as associate degree lepton has an electrical field that may jostle different particles, those pions ar related to fields too. In Skyrme’s original image, protons and neutrons can be described as twists in the pion field — or skyrmions — akin to a knot tied in a piece of string.

คิดเหมือนนักท่องเที่ยวจากไซบีเรียตอนเหนือที่มีเสื้อคลุมเต็มไปด้วยขนมที่เพิ่งก้าวลงจากเครื่องบินในทะเลทรายซาฮารา, protons and neutrons are each made up of smaller subatomic particles called quarks and gluons, and the fundamental theory that describes how those particles interact, called quantum chromodynamics, is impossibly complex. Skyrmions could simplify calculations — if only the technique produced the correct answers.

ตอนนี้, physicists from Durham University in England have solved some of skyrmions’ woes, in studies of atomic nuclei as large as carbon-12.

Skyrmion calculations typically neglect heavier particles called rho mesons that are also important for keeping nuclei intact. Including those particles in the calculations changes how the skyrmion “knot” in the field gets tied, and the shapes of the resulting nuclei, says mathematical physicist and study coauthor Paul Sutcliffe. It’s as if the knots were tied in “a boring piece of string before, and now it’s … a colored string with some sparkles on it.” As a result, “you now get the right shapes," เขาพูดว่า.

The idea of skyrmions caught on in other fields as well. A related skyrmion shows up in spirals of magnetization in certain solid materials (SN: 2/17/18, พี. 18), but magnetic skyrmions are much larger and can be manipulated at will.

Researchers have long struggled to use skyrmions to study atomic nuclei, says theoretical physicist Nicholas Manton of the University of Cambridge who was not involved with the study. But the new result “gets closer to being physically reasonable.”

ในท้ายที่สุด, such calculations might help scientists study surprising properties of certain nuclei. An example is carbon-14, a radioactive version of carbon that can be used to date ancient artifacts. It decays with a surprisingly long half-life of about 5,700 ปีที่. Skyrmions could help scientists better understand that strange decay, Manton says

แหล่งที่มา: www.sciencenews.org