BNL’s Anze Slosar looks at how the universe behaves
Distant clouds, light and shadows, black energy are all part of his research
Anze Slosar has his head in the clouds. No, not the ones that drop rain or that provide a welcome respite from the sun in July, but the ones at the edge of the universe, as many as 11 billion light years away.
An assistant professor at Brookhaven National Lab, Slosar is a cosmologist who looks at the way hydrogen clouds absorb light and change its color as it makes the long journey to Earth.
The way light from quasars — bright regions that can be a trillion times brighter than the sun — passes through hydrogen gas clouds helps paint a picture of the expanding universe.Slosar will be examining light from thousands of points of light to create a three dimensional map. He is currently analyzing 60,000 quasars and has another 100,000 in hand.
“I sometimes fool myself into thinking I’m like Christopher Columbus, discovering new structure in the world,” he offered.
He looks at the graphs that show statistical properties of those clouds. Slosar’s promising work in creating maps with the Lyman Alpha Forest — as this technique of using the shadows through hydrogen gas to recreate maps of the early universe is known — has earned him distinctions.
Last year, his proposal was one of only 65 chosen for funding from 1,150 submitted by researchers around the country. The funding will support five years of research.
He likens his efforts to put together a picture for a Chinese puppet show, where he sees traces of objects through the clouds.
He is participating in the Sloan Digital Sky Survey, which operates one of the world’s largest digital cameras, based in Apache Point, N.M. Slosar said he doesn’t look through the lens of the telescope at the images. Rather, he collects the digital data and uses computer programs to analyze, interpret and make sense of the nature of the universe.
The universe had a tremendous explosion of energy — the Big Bang — billions of years ago. After the Big Bang, the pieces of the universe would be expected to stop moving away from each other, and might even turn over and begin to collapse, he explained. Instead, they are expanding at an accelerated rate.
Physicists believe so-called dark energy is responsible.
Explaining dark energy using familiar objects, Slosar suggests “imagine throwing a stone in the air. You would expect it to slow down completely and start returning. You could also expect it to never return if you threw it so energetically that it would leave the Earth and travel in empty space. However, you wouldn’t expect it to suddenly start to speed up and this is what is happening with dark energy.”
“It’s undeniably there,” Slosar said. “You can’t touch it, but we can measure its effects on the expansion of the universe.”
While he feeds his scientific interests by looking back in time at a map of the universe, he said the pursuit itself includes challenges and frustrations.
More often than he’d like, he comes to his office and sits “at my computer and I swear, because the program doesn’t work the way it should,” he laughed.
Slosar recognizes the pursuit of basic science itself doesn’t improve the productivity of a crop, lower the cost of gasoline or create a sturdier structure that won’t collapse in a strong wind. It can and does provide other benefits, including feeding the minds of those curious enough to ask questions about the universe.
“There are always nice side effects from science,” he said. “The Internet came from fundamental research. The side effect of developing rocket science is going to the moon. Whenever you try to do something hard, you inevitably learn new things.”
A permanent resident of the United States, Slosar lives in Queens with his wife Maja Bovcon, who was his high school sweetheart when they grew up in Slovenia. Bovcon got her Ph.D. in political science from Oxford, while Slosar earned his doctorate from Cambridge “as if we were both British aristocrats, but instead we are from working-class families from Slovenia.”
Bovcon is at the end of a three-month-long study in Senegal.
Slosar explained that his work is “trying to make sense of how the universe behaves as a physical system. What is it made of, how did it begin and how will it end up?”