Quantum gravity: we explore spin foams and other potential solutions to this enduring challenge
Earlier this autumn I had the pleasure of visiting the Perimeter Institute for Theoretical Physics in Waterloo Canada – where I interviewed four physicists about their research. This is the second of those conversations to appear on the podcast – and it is with Bianca Dittrich, whose research focuses on quantum gravity.
Albert Einstein’s general theory of relativity does a great job at explaining gravity but it is thought to be incomplete because it is incompatible with quantum mechanics. This is an important shortcoming because quantum mechanics is widely considered to be one of science’s most successful theories.
Developing a theory of quantum gravity is a crucial goal in physics, but it is proving to be extremely difficult. In this episode, Dittrich explains some of the challenges and talks about ways forward – including her current research on spin foams. We also chat about the intersection of quantum gravity and condensed matter physics; and the difficulties of testing theories against observational data.
The first interview in this series from the PI was with Javier Toledo-Marín: “Quantum computing and AI join forces for particle physics”
IOP Publishing’s new Progress In Series: Research Highlights website offers quick, accessible summaries of top papers from leading journals like Reports on Progress in Physics and Progress in Energy. Whether you’re short on time or just want the essentials, these highlights help you expand your knowledge of leading topics.
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Talking physics with an alien civilization: what could we learn?
It is book week here at Physics World and over the course of three days we are presenting conversations with the authors of three fascinating and fun books about physics. Today, my guest is the physicist Daniel Whiteson, who along with the artist Andy Warner has created the delightful book Do Aliens Speak Physics?.
Is physics universal, or is it shaped by human perspective? This will be a very important question if and when we are visited by an advanced alien civilization. Would we recognize our visitors’ alien science – or indeed, could a technologically-advanced civilization have no science at all? And would we even be able to communicate about science with our alien guests?
Whiteson, who is a particle physicist at the University of California Irvine, tackles these profound questions and much more in this episode of the Physics World Weekly podcast.
This episode is supported by the APS Global Physics Summit, which takes place on 15–20 March, 2026, in Denver, Colorado, and online.
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Better coffee, easier parking and more: the fascinating physics of daily life
It is book week here at Physics World and over the course of three days we are presenting conversations with the authors of three fascinating and fun books about physics. First up is my Physics World colleague Michael Banks, whose book Physics Around the Clock: Adventures in the Science of Everyday Living starts with your morning coffee and ends with a formula for making your evening television viewing more satisfying.
As well as the rich physics of coffee, we chat about strategies for finding the best parking spot and the efficient boarding of aeroplanes. If you have ever wondered why a runner’s ponytail swings from side-to-side when they reach a certain speed – we have the answer for you.
Other daily mysteries that we explore include how a hard steel razor blade can be dulled by cutting relatively soft hairs and why quasiparticles called “jamitons” are helping physicists understand the spontaneous appearance of traffic jams. And a warning for squeamish listeners, we do talk about the amazing virus-spreading capabilities of a flushing toilet.
This episode is supported by the APS Global Physics Summit, which takes place on 15–20 March, 2026, in Denver, Colorado, and online.
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Designing better semiconductor chips: NP hard problems and forever chemicals
Like any major endeavour, designing and fabricating semiconductor chips requires compromise. As well as trade-offs between cost and performance, designers also consider carbon emissions and other environmental impacts.
In this episode of the Physics World Weekly podcast, Margaret Harris reports from the Heidelberg Laureate Forum where she spoke to two researchers who are focused on some of these design challenges.
Up first is Mariam Elgamal, who’s doing a PhD at Harvard University on the development of environmentally sustainable computing systems. She explains why sustainability goes well beyond energy efficiency and must consider the manufacturing process and the chemicals used therein.
Harris also chats with Andrew Gunter, who is doing a PhD at the University of British Columbia on circuit design for computer chips. He talks about the maths-related problems that must be solved in order to translate a desired functionality into a chip that can be fabricated.
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Unlocking the potential of 2D materials: graphene and much more
This episode explores the scientific and technological significance of 2D materials such as graphene. My guest is Antonio Rossi, who is a researcher in 2D materials engineering at the Italian Institute of Technology in Genoa.
Rossi explains why 2D materials are fundamentally different than their 3D counterparts – and how these differences are driving scientific progress and the development of new and exciting technologies.
Graphene is the most famous 2D material and Rossi talks about today’s real-world applications of graphene in coatings. We also chat about the challenges facing scientists and engineers who are trying to exploit graphene’s unique electronic properties.
Rossi’s current research focuses on two other promising 2D materials – tungsten disulphide and hexagonal boron nitride. He explains why tungsten disulphide shows great technological promise because of its favourable electronic and optical properties; and why hexagonal boron nitride is emerging as an ideal substrate for creating 2D devices.
Artificial intelligence (AI) is becoming an important tool in developing new 2D materials. Rossi explains how his team is developing feedback loops that connect AI with the fabrication and characterization of new materials. Our conversation also touches on the use of 2D materials in quantum science and technology.
IOP Publishing’s new Progress In Series: Research Highlights website offers quick, accessible summaries of top papers from leading journals like Reports on Progress in Physics and Progress in Energy. Whether you’re short on time or just want the essentials, these highlights help you expand your knowledge of leading topics.
Physics World Weekly offers a unique insight into the latest news, breakthroughs and innovations from the global scientific community. Our award-winning journalists reveal what has captured their imaginations about the stories in the news this week, which might span anything from quantum physics and astronomy through to materials science, environmental research and policy, and biomedical science and technology. Find out more about the stories in this podcast by visiting the Physics World website. If you enjoy what you hear, then also check out our monthly podcast Physics World Stories, which takes a more in-depth look at a specific theme.
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