Science at Cambridge: The Compelling and Creative World of Physics

Halfway through my degree, I can confidently say that there’s nothing I would rather be doing. Physics is a stimulating subject in so many ways, allowing a really deep understanding of how the physical world works, which can be excitingly counterintuitive.

Studying physics was a natural choice for me – I’ve always loved playing with maths, and physics extends that into making you consider what the maths is telling you about the real world. I enjoyed reading about physics at school, and studying it at university makes everything you’ve read in popular science books so much more compelling, by giving you tools to truly understand the concepts, and then use them to answer questions about how the universe operates.

It is not just the subject matter, but also the act of doing physics; I get a real rush as I suddenly figure out how to finish a question after over an hour’s thinking.

There’s so much stuff happening in the course: with labs, supervisions and extremely fast-paced lectures, it’s not possible to get bored. Many people wouldn’t consider physics to be a creative subject, but I would argue differently: devising solutions to problems you’ve never seen before requires a lot of creativity, and I think studying physics really demands and develops both this creativity and an analytic mind.

I have really enjoyed quantum mechanics this year, because the course hasn’t just introduced new concepts, but also new ways of thinking, in terms of symmetries, inner products and probabilities. This is one of the things I like most about studying physics: thinking in new ways is challenging, but also very exciting. It’s also satisfying just to be able to make predictions about the way microscopic systems behave, when it is so distant from my previous knowledge of the world. I’m really looking forward to third year as it will give me the chance to study subjects like particle physics which I have only previously read about in popular science books and news articles. I’m also excited to be able to do some of my own research, particularly in fourth year.

Murray Edwards is the best place I can imagine to study. There’s a real sense of community, where everyone wants to see everyone else succeed, and it’s inspiring to be surrounded by other women who are equally passionate about science. I’ve just started a year as co-chair of Cambridge University Physics Society, something which I could never have envisaged doing when I was at school. I think studying in Cambridge really gives you the courage to do crazy things!

Physics is a fantastic subject to study in all ways – stimulating, challenging, and ultimately rewarding.

The last two years have been thoroughly enjoyable and inspiring, and I feel confident knowing that whatever I choose to do after I graduate, my degree will have prepared me for it.

Fionn Bishop
Undergraduate student

Career Path: Understanding dark matter – a collaborative venture

16a-sarah-williamsAs a researcher on the ATLAS experiment at the Large Hadron Collider at CERN, one of the things I love about my job is that on a day-to-day basis I get to interact with scientists from different backgrounds all around the world. The ATLAS collaboration includes around 3000 physicists from over 175 institutes around the world, all working together to answer fundamental questions about the elementary particles and interactions in the universe.

My work focuses on searches for new particles at the LHC, and in particular those that could help explain what makes up Dark Matter in the universe.

Astrophysicists now believe that dark matter makes up nearly 25% of the mass energy content of the universe (with only 4% being normal `baryonic matter’ which we can explain and the rest being dark energy, a mysterious substance that actually causes the expansion of the universe to accelerate). Although we don’t currently know what dark matter is made of, there is strong evidence that it could constitute a “weakly interacting massive particle” (or WIMP) which could thus be searched for in the high energy collisions at the LHC.

The LHC collides bunches of protons together around 40 million times a second, and recording these collisions requires enormous detectors (the ATLAS detector is around half the size of Notre Dam Cathedral in Paris and weighs as much as the Eiffel tower). Most particles produced in collisions decay instantly so we can only indirectly infer their existence by trying to reconstruct information from their decay products. The data is read off the detector, reconstructed and stored at large computing sites all over the world waiting to be analysed offline by particle physicists.

It is very rare to perform a LHC search on your own, it normally takes a group of a dozen or more physicists working together to produce the final result.

For example, I tend to work a lot on the statistical analysis, which considers quantitatively the level of agreement between the observed data and the prediction based on the Standard Model (which encapsulates our current understanding of the elementary particles on the universe).

Another aspect of my work that I appreciate is the variety of skills that I have gained and used over the years in carrying out my research. The large volumes of LHC data makes computer programming unavoidable, so I have had to learn a variety of programming languages including c++ and python. In addition to that, working in such a large collaboration requires strong communication skills. Before I started my PhD I had very limited experience of public speaking however I very quickly became accustomed to presenting on a weekly basis. I have also had the opportunity to present at international conferences around the world, including in Taipei, Moscow and later this month in Adelaide.

There are so many fundamental questions within the sciences that are waiting to be answered.

Challenges range from finding alternative energy sources that can be exploited on a global scale, to developing new techniques for the diagnosis and treatment of life-threatening diseases.  We need young women (and men) with a passion for new knowledge, the creativity to solve problems and the personal qualities to engage effectively in interdisciplinary teams.  It’s an exciting and rewarding field and can provide you with many unexpected opportunities along the way.

Sarah Williams
Alumna

Career Path: Exploring fingerprints from the Big Bang

Reader in Astronomy at UCL
Picture by Max Alexander

Career
I am a cosmologist. In my research, I am contributing to an international effort to understand the origin and the evolution of the Universe. It is amazing that this is even possible, because it involves extreme physics that we cannot replicate in the laboratory. However, at the Big Bang, the Universe itself performed the ultimate physics experiment. The clues to this physics are imprinted upon the oldest light we can see in the Universe, the so-called cosmic microwave background, and the large scale distribution of galaxies. Because the ultimate experiment was done once, and we can’t repeat it, cosmologists have to become detectives. Different theories of the universe produce different fingerprints in these data, and we sift through the fingerprints looking for which one matches what we observe. We are trying to piece together the clues to figure out the narrative about how our Universe began, and how it is evolving. In the past decade we have been able to precisely answer age-old questions such as how old is the Universe, what does it contain, and what is its destiny. Along with these answers have also come many exciting new questions.

Reader in Astronomy at UCL
Picture by Max Alexander

Modern cosmological research is a very collaborative and international enterprise. My work involves a lot of mathematics and high performance computing, the development of advanced algorithms and highly specialized databases to store and sift through the massive amounts data returned by cosmological sky surveys. Some of this work requires me to work in small groups with two or three other researchers, but I also contribute to large global projects with several hundred people in many countries. Since cosmology is very international, I travel extensively, discussing research findings, giving talks, and running workshops and seminars. I also enjoy sharing my knowledge and enthusiasm with my undergraduate and postgraduate students at the university.

Young women today should consider choosing to study the sciences because scientific research is intellectually stimulating, fun, and enables a huge range of careers within and outside academia.

“Blue skies” research is extremely important for our society, and for humanity as a whole, because one can never predict where the next breakthrough is coming from. In addition, science students are trained to think independently and out of the box, and they are adept at using incomplete data to reach useful and robust conclusions. They are often excellent computer programmers. They have great communication and time management skills. For these reasons they are highly sought-after in industry, engineering and finance.

Professor Hiranya Peiris
Alumna (New Hall/Murray Edwards College)

Prof. Peiris is Professor of Astrophysics at University College London.

 

School Winner: The Intricacy of Our Universe

Winning Entry bannerSchool1C Molly1 with permission

Whilst reading “A Journey through the Universe: Gresham Lectures on Astronomy” by Ian Morison it struck me how many unanswered questions, uncertainties and conflicting theories we have regarding our universe‘s composition. As science progresses with the discovery of new constraints and laws, it’s becoming much harder to cope with the intricacy of our universe as we know it. As I see it, our universe is a very complex entity and no one person could retain knowledge about its entirety. So, do our brains, a product of this universe, have the capacity to understand it?

There are many setbacks concerning our understanding of the universe, especially the conflict between highly regarded theories and laws that govern its existence. For example, one problem encountered is the fact that we cannot combine Einstein’s Theory of Relativity with the more modern Quantum Theory. The main obstacles physicists faced when combining the two theories was the difficulty of incorporating the fourth force, gravity, into the Standard model of quantum mechanics, along with the other 3 forces and all 17 of the elementary particles. The fundamental incompatibility of these areas of cosmology represented by quantum mechanics and general relativity is yet to be solved, however we should ask ourselves what if our brains have no means of ever comprehending a combination of the many theories out there? There are so many different ways of describing the totality of the cosmos so how will we ever reach the desired “Grand Unified Theory”?

Although the idea that our brain capacity limits our understanding of our universe is a bleak one, I find the concept of our universe being totally uncomprehensive very exciting. It allows the possibility that whilst humans are imprisoned in only 3 spatial dimensions, unbeknown to us, there could be millions of other dimensions out there. It offers concepts such as the Multiverse; parallel dimensions and alternate realities to our own, which is mind-blowing.

History has shown us that human limitations do not always impact great scientific discoveries, however eccentric they may have seemed at the time. Many of the far-fetched concepts that scientists proposed in the past, which were considered improbable by human logic of that time, have gone on to form the well-known scientific theories of today. For example, in 1543, Copernicus proposed the first heliocentric model of the solar system, which strongly opposed the prevailing astronomical model of the cosmos at that time – the Ptolemaic system. Even Tycho Brahe, an arguably accomplished astronomer of his time, rejected the Copernican model, thereby showing that new concepts are difficult for humans to understand.

Ultimately, we may live in a universe that is so beyond our comprehension that we shall never be able to reconcile the Theory of Relativity and the Quantum Theory into one unifying “Grand Theory”. Or maybe we are simply not quite there yet? The nature of humanity is, however, to explore and therefore I think that even if the end goal is unreachable, we must still strive to attain it.

Molly Haigh
Year 12
Maidstone Grammar School for Girls

1C Molly3 (with permission - cropped)

“My name is Molly Haigh and I am currently studying for A levels in Art, Maths, Physics and Spanish at Maidstone Grammar School for Girls. I have always had an interest in Astrophysics, which was heightened further whilst undertaking an Oxford University module titled ‘Exploring the Universe’. There are still many interesting unanswered questions regarding this subject, which is one of the reasons why I hope to study this exciting branch of physics at University.”