UD’s Swati Singh receives National Science Fo
Swati Singh of the University of Delaware was a curious child. If you ask her parents, they’ll likely recount the many times she took her toys apart while trying to figure out how they worked. She broke a lot of things for the same reason.
In college, Singh realized that she could harness this curiosity as a scientist, after a crucial conversation with her father. She had asked her father how a light bulb worked. The answer, she said, comes down to electrons.
“He said, ‘But have you ever seen an electron? “I told him no and he said, ‘Just believe it,'” she said of the conversation. “I still haven’t seen an electron, but there are reasons I think it exists.”
Singh, now an assistant professor at UD in electrical and computer engineering, is still searching for answers about the unknown. These days, her focus is on understanding dark matter and dark energy, the mysterious substances that make up over 95% of the universe but cannot be measured using existing devices. Together, dark matter and dark energy are known as the dark sector.
It’s a fitting field for the girl who once believed in something she couldn’t see that science claimed was there, and the much-respected quantum physicist and electrical engineer she has become. In his work, Singh has carved out a niche for himself by researching ways to reuse existing tabletop sensors for dark matter detection.
Now, the National Science Foundation has awarded Singh a Five-Year, $ 400,000 Early Career Development Award (NSF CAREER) to explore new methods of studying the dark sector using additional mechanical devices operating in the dark sector. classical and quantum domains.
Singh hopes this foundational work will lead to new precision measurement systems to detect astrophysical signals.
Studying the Dark Sector
So, a quick primer: Ordinary matter includes all things that emit light, like gas, dust, stars, planets, and us. Dark matter includes everything else – it doesn’t emit light, but researchers know it exists through its gravitational effects. Dark energy, on the other hand, is an unknown form of energy / matter present throughout the universe which is responsible for the accelerated expansion of the universe.
When normal matter is coupled with dark matter or dark energy, it can manifest itself through a mechanical effect, such as stresses, recoils or accelerations. Accurate monitoring of mechanical movement could give scientists unprecedented access to these tiny signals, Singh said. She wishes to integrate new results from quantum physics, where recent work offers interesting avenues for looking for very weak signals.
To begin with, Singh plans to answer some basic questions about the nature of dark matter itself. For example, instead of swimming in a sea of dark matter like her research had assumed, what if there was a wave of dark matter passing through her at specific times? According to Singh, this would alter the resulting signal.
She also plans to use a fiber-based broadband detector to search for dark matter in the infrasonic range, which is below 20 hertz, the threshold for human hearing. Things that produce sound in this frequency range include earthquakes or volcanoes.
“We plan to take some of the best fiber optic cables, put them in a low noise environment, and use them as a ruler to try and measure small length corrections that would occur if dark matter was present,” Singh said.
In addition to the dark matter research in her group, she is teaming up with an experimental group in Alberta, Canada, who are building a superfluid helium-based detector for dark matter. The collaborative effort builds on Singh’s early work using helium-based detectors to detect gravitational waves. She and doctoral student Jack Manley will spend time at the University of Alberta as visiting scholars to learn and contribute to this detection effort through an American Physical Society Innovation Award, funded by the Gordon and Betty Moore Foundation to solve pressing problems in fundamental physics. .
In another arc of the work, Singh wants to learn more about what dark energy might be and why it has no effect on human-made devices.
She explained that mass of normal matter and dark matter both bend the fabric of spacetime, which we call gravity, much like a stone placed on a piece of fabric would bend the material. In the cosmos, however, the universe is also expanding at the same time. And, observations have shown that the fabric of space-time is more than stretching, it is stretching faster than in the past. So something is touching the gas.
Singh plans to use spherical silica microparticles and membrane detectors as sensors to probe what might be dark energy. She said that when scientists carefully examine the force between the sun and the earth, the earth and the moon, or two balls in a lab, they only see Newton’s law of gravity at work to bring these masses together. Meanwhile, research tells us that galaxies are simultaneously expanding relative to each other.
This cosmic acceleration is attributed to dark energy. So why can scientists only detect gravity?
One possible explanation, Singh said, is that in the absence of matter – say in the empty space between two galaxies – cosmic acceleration dominates. But when it comes to matter coming from a galaxy, the solar system or terrestrial objects like balls in a laboratory, this acceleration effect is “masked” or masked.
Whether the density of an object plays a role in this effect is an open question. For example, what if interstellar dust, which is light, has less shielding than a lump of lead on Earth which has a higher density? If correct, it might help explain why researchers would observe cosmic acceleration at larger scales, but closer to home, where objects from pebbles to planets are denser, this acceleration is masked, leaving only the detectable severity.
“These are ideas very much dependent on density and geometry,” Singh said. “My PhD student Joey Betz is working on math and looking at a variety of mechanical sensors with different shapes and materials to calculate how this size button and geometry button can tell us about changes in gravity due to energy. black. “
Inspire current and future peers
By helping to establish experimental boundaries on various connections between the dark sector and normal matter, Singh aspires to stimulate high-energy theoretical research in new models of dark matter and dark energy. She also hopes the work can inspire improved collaboration and a common language in several areas involved in the study of the Dark Sector, where perspectives from cosmology or astronomy reach the lab, and information from lab research informs. theoretical areas. To foster this type of collaboration, Singh regularly involves cosmologists and experimenters in the development of ideas his students are working on.
Additionally, Singh wants to motivate the next generation of scientists, especially women, to stay curious.
“I don’t want to be one of the few people working in this field, so I feel the need to open the door for everyone, like my mentors have done for me,” she said. .
Singh recently had the rare opportunity to learn more about his own influence when alumni from disparate areas of his college life came together to celebrate his success in the NSF CAREER.
“They weren’t students in my research lab, they were people I had taught over the years,” she said. “It was such a special time because my research achievements were celebrated by students I only interacted with in a classroom.”
This is the kind of momentum Singh wants to continue. To this end, she regularly interacts with students involved in engineering organizations on campus, such as the Society of Women Engineers and Women in Electrical and Computer Engineering, and she plans to collaborate with the College’s K-12 program. of Engineering on ways to share dark matter. and research on dark energy with middle and high school students as part of its CAREER award. Singh has developed a course to help UD students understand quantum computing by also developing computer games. The course arose out of a lecture given by Singh in a cryptography course that led to a project with several students, in-depth questions on the mathematics of game theory and even a collaboration with Ivan Todorov, professor of science. mathematics.
“Science does not take place in a vacuum. Instead, advancements are often inspired by scientists working at the interface of different fields, ”Singh said.