Cheng Foo

PhD Student in the “Astrophysical and Cosmological Relativity department”

What is your current position at our institute?

I’m a PhD Student in the Astrophysical and Cosmological Relativity department, supervised by Prof. Alessandra Buonanno.

How and when did you choose to do physics?

In high school, I was inspired by science outreach books and talks, and became fascinated by big questions about the universe and our place in it. I chose an undergraduate degree in Physics and Philosophy where I could explore these ideas in depth. I really loved studying General Relativity in my third year of this degree and decided to go fully into theoretical astrophysics after that. 

What is your academic education?

• Max Planck Institute for Gravitational Physics (Albert Einstein Institute), PhD (2023 - Now)
• ETH Zürich: MSc Physics (2021 - 2023)
• University of Oxford, Trinity College: MPhysPhil Physics and Philosophy (2017 - 2021); fully supported by the Jardine Scholarship

Did you have someone who acted as a role model or mentor to you in the past, or does so in the present? What is the most important thing you learned from them?

My mother is a physicist, and seeing her genuine love and excitement for science helped me understand from a young age that math and physics were something very exciting! Later, in high school, I realised how much I enjoyed these subjects, and having such a strong female role model in my mother gave me the confidence to pursue physics myself. Along the way, I have been supported by many other female role models and mentors, from fellow PhD students and postdocs to my current supervisor and my master’s thesis supervisor. These successful women around me have made me feel more comfortable in the field, especially in moments when I have doubts about my place in the field.

What would you recommend to a young woman wanting to start a career in physics?

Believe in yourself! Reach out to women within the field and get in touch with Women in Physics / STEM organisations. Though it is unfortunately still true that there is a gender imbalance in the field, it is slowly improving, and connecting with others who share similar experiences can be very reassuring and help build a sense of community.

What measures that target women and girls in science would you care about and/or would you like to see realized in the scientific community?

Greater involvement from all genders in equal opportunity efforts, increased awareness of biases faced by women and other minorities, and stronger support through fellowships and initiatives aimed at achieving parity.

What is your vision for women and girls in science in 20 years?

Full gender parity at every level. I want it to be such that when people imagine a scientist / physicist, they imagine both women and men equally.

Why did you choose the Max Planck Institute for Gravitational Physics for your research?

The division has exceptional breadth and depth of expertise. For almost any question I have, there is someone whose door I can knock on, making it an ideal environment for learning and research.

Can you please describe your research focus?

My research focuses on modelling the gravitational waves emitted by merging binary black holes – ripples in spacetime produced during some of the most extreme events in the universe. These theoretical waveform models are essential for interpreting data from observatories such as LIGO, which made the first-ever direct detection of gravitational waves in 2015, ushering in a new era of gravitational-wave astronomy. Gravitational-wave science now allows us to “listen” to the cosmos, revealing otherwise invisible phenomena and enabling us to probe the nature of black holes, test Einstein’s theory of relativity, and uncover the history of the universe. 

Do you have a favorite figure from a publication you co-authored?

Accurate waveform modelling is crucial for reliable gravitational-wave data analysis, both to understand the sources and to test general relativity. Most current analyses use precessing binary black hole waveforms. Precession occurs when the black hole spins are misaligned with the orbital angular momentum, causing the plane of orbit to precess, and thus complicating the signal.

In our work, we investigated a source of bias in widely used precessing waveform models and studied its impact across parameter space. This figure shows the identified regions where inaccurate modelling could lead to apparent – but false – violations of general relativity, helping analysts understand model limitations and guide future improvements.