Light from a lamp or a star, passing through matter, leaves its mark: atoms absorb some colors and let others through. The result is a spectrum — a colored strip with dark lines, like a barcode that reveals the chemical composition. But some atoms and molecules have unpaired electrons — loners that behave unpredictably and complicate calculations.
The authors of the study found a way around this difficulty. They applied two sequential steps: first, they "freeze" the motion of electrons to find the desired state of the atom, then they "turn on" time and watch how the atom interacts with light. This approach is like shooting slow-motion video: first you take a sharp still frame, then you start recording to see the dynamics.
The results matched accurate but slow calculations, while the new method works faster. This is important because the spectra of such systems are needed in astrophysics, atmospheric chemistry, and the creation of new materials.
Now scientists can more quickly decipher the "barcodes" of light from distant stars and earthly laboratories.
An atom's spectrum is like a fingerprint: each element has its own unique set of absorption lines.
In the series "Star Trek," spectral analysis is used to determine the composition of distant planets' atmospheres, the new method would speed up such calculations.