Transforming our understanding of dark matter and energy

The quest to understand the universe is set to receive a significant boost through innovative research conducted by Professor Amanda Weltman, head of the High Energy Physics, Cosmology and Astrophysics Theory (HEPCAT) group at UCT.

In her recent inaugural lecture titled “From the Laboratory to the Sky: New Windows on the Universe,” Professor Weltman highlighted how advancements in radio sky technology can transform scientific exploration and deepen our comprehension of cosmic phenomena.

With a remarkable academic trajectory adorned with over 10 000 citations and various prestigious awards, Professor Weltman is a leading figure in theoretical physics.

Her journey to prominence, including her promotion to full professor in 2020, has made her a beacon of inspiration in the realm of scientific research. During her lecture, she acknowledged the foundational impact of her parents, both passionate mathematicians, in fostering her academic ambitions.

“My approach to theoretical physics is rooted in three key pillars: mathematics, physical intuition, and creativity,” she shared, underscoring the importance of a multifaceted approach to solving profound scientific questions.

Professor Weltman took the audience on a sweeping cosmic voyage, addressing topics ranging from the intricate vibrations of matter to the boundless universe. One of her significant contributions is the development of “chameleon gravity,” a novel theory she conceived during her PhD studies.

“We have made many efforts over the years to discover its effects in laboratory and astrophysical observations,” she remarked, illustrating her commitment to bridging theoretical inquiry with empirical evidence.

One of the most provocative points of her lecture was the acknowledgment that less than 5% of the universe's total energy is comprehensible to humanity.

“Ninety-five percent of it is dark. We call it dark matter and dark energy simply because it doesn't interact with light,” she stated, drawing attention to the monumental mysteries that still elude our understanding in the field of cosmology.

The presentation also touched on her recent studies of fast radio bursts (FRBs) – high-energy astrophysical phenomena that have captivated scientists since their serendipitous discovery.

“Understanding these bursts could provide insights into the nature of the universe and the fundamental forces that govern it,” she explained, delineating the potential these eruptions hold for groundbreaking discoveries in physics.

Professor Mosa Moshabela, UCT vice chancellor, emphasised the essence of inaugural lectures, stating, “They capture in one moment the long, arduous journey that the scholar has travelled to get to where they are.” He noted that such moments celebrate the scholar's work and its broader implications for the academic community and society at large.

Weltman, who earned her PhD under the mentorship of celebrated physicist Professor Brian Greene at Columbia University and later conducted research at the University of Cambridge, returned to South Africa in 2007.

She established the HEPCAT group at UCT, now a hub for pioneering research. In her career, she has received accolades such as the Meiring Naude

Medal and the Elsevier Young Scientist Award, culminating in her 2021 appointment as a South African Research Chair in Physical Cosmology.

Professor Jeff Murugan, UCT's acting deputy vice-chancellor for research and internationalisation, praised Professor Weltman's ability to harmoniously balance research, teaching, and mentorship.

“Only a select few of us will ever have the privilege of being able to ask the right questions at precisely the right time. Amanda is one such rare scientist,” he remarked, acknowledging her unique role as a mentor and scholarly leader.

As the scientific community continues to probe the enigmatic expanses of the universe, Professor Weltman's innovative approaches and steadfast inquiry serve as a compelling call to action for future generations of physicists. Her work guarantees that the journey from the laboratory to the sky remains replete with promise and discovery.

Weekend Argus