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

Science at Cambridge: Physics

Physics – my everyday worldUniversity 10D Lucy OswaldMonday morning and spring is in the air. On the short trip between my Particle Physics and Astrophysical Fluid Dynamics lecture locations I hand in some work and photograph a sea of daffodils, nodding at me in the breeze. In the following lecture we cover blast waves: gas from supernovae and other massive explosions moving through space faster than the speed of sound. Then it’s back to college for a quick lunch before a Particle Physics supervision, where we talk about how quarks and gluons interact.

The rest of the afternoon is spent doing something that as a physicist I’ve not previously been used to: reading! I’m doing a research review which involves reading papers on the research done into single photon sources – devices that produce one particle of light at a time – and then summarising the recent developments in the area. It’s been exciting to get deep into an area of research that previously I knew nothing about.

I chose Natural Sciences at Cambridge out of a kind of greed for knowledge: why study just one science when you had the opportunity to do more? I’ve never regretted that choice. The only hardship is having to decide what to give up along the way, something that continues to happen as I’ve begun specialising in my third year. I really value the wider insight I’ve been given by being able to study Chemistry and Materials Science alongside the Physics. So much science happens at the boundaries of these different disciplines, so understanding where your studies sit in the wider context of scientific knowledge is very important.

However, Physics has always been the subject that has captivated me the most. In my more wildly romantic moments I’ve declared that I must KNOW about the world and how it works; that to study Physics is to plumb the depths of reality. Unsurprisingly, Physics day-to-day isn’t nearly as glamorous as that makes it sound, but the fact that I’ve maintained that idealised view through nearly 3 years of worksheets and practicals indicates that there must be something special about it.

Physics isn’t everyone’s cup of tea. It can be difficult to get your head around, involves lots of maths and areas like quantum mechanics can seem so divorced from the real world that it’s easy to condemn it as too complicated, boring and irrelevant. But if you have even the smallest interest in physics I would encourage you to take it a bit further. It started for me by shining laser pointers onto fluorescent paper and wondering why the green one made it glow but the red one didn’t. I soon realised Physics wasn’t so bad and now there’s nothing I’d rather do!

Lucy Oswald
Undergraduate student

Science issue: The gloopy world of collagen proteins

9B Ying Chow photo1NewsI always find it a little misleading to tell people that I am a chemist; the molecules that I am studying come from biology, while the technique that I use comes from physics.

The samples I have investigated included bone, tendon, cartilage, and skin; a diverse variety of materials somehow all made from collagen proteins. Together with a range of other proteins, sugar-like molecules, and sometimes minerals, collagen proteins form the extracellular matrix — the glue-like matrix in which cells are embedded and organised. However, it is not just a passive scaffold: the cells make attachments to the matrix at an atomic level, and this attachment can trigger different cell behaviours. So what are these atomic-level “hooks” that the cell is seeing?

Perhaps a little surprisingly, it is not easy to study the atoms in the extracellular matrix. Since it is a gloopy/grainy, cross-linked, heterogeneous mix of proteins, sugars, and more, there is a mind-boggling variety of different kinds of atoms and molecules within a small piece of tissue. Often, a shortened section of pure collagen-like proteins is studied as a simpler model system. However, what if we could have a technique where we can directly compare healthy tissue and diseased tissue atomically? Perhaps we can understand how the differences in bulk property (e.g. stiffness, brittleness) came about, by understanding the molecular and atomic level organisation (e.g. different compositions, different chemical bonds). Changes in the extracellular matrix occur in many diseases, including diabetes and cancer, but also naturally over time as we age. Much of current treatment focuses upon the cells, or surgically removing diseased tissue, but perhaps there are ways to more effective treatment if we can understand, reverse or even prevent these changes at a tissue level.

Much of my research is about developing an approach to study tissues in an intact manner at an atomic level. The technique that I use, solid-state nuclear magnetic resonance spectroscopy (ssNMR), can sometimes feel like it is a world apart from biology, full of electronics, pulse programming, and liquid nitrogen. All the machinery is part of an attempt to delicately (well, as delicately as you can with a kilowatt of power) nudge the quantum mechanical states of those atoms within the sample, to find out what bonds those atoms are making, what other atoms are nearby, in order to deduce what molecule that atom is a part of. Interpreting the data is much like solving a logical puzzle, trying to fit all the pieces of information to what we know about the experiment and the sample.

At the moment, I am trying to work out why some parts of collagen proteins appear to be more flexible than others, which may help cells form attachments onto the collagen matrix. Using ssNMR, I could pick out the flexible atom pairs, which exerted a smaller magnetic (dipolar) effect on each other.

As a chemist who is working at the border between disciplines, I am always working with a range of scientists from different backgrounds: cell biologists, biochemists, computational chemists, and even engineers and doctors. It is an enriching experience, full of creative solutions, and even more creative questions.

If you are interested to find out more, feel free to ask by email or Twitter!

Ying Chow
Alumna

Further reading:

Protein Databank 101 Molecule of the month: Collagen
http://pdb101.rcsb.org/motm/4

Molecular Biology of the Cell (Alberts et al, 2002)
http://www.ncbi.nlm.nih.gov/books/NBK26810/

The Extracellular Matrix at a Glance (Frantz 2010)
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2995612/?tool=pmcentrez

Some introduction to solid-state NMR
http://u-of-o-nmr-facility.blogspot.de/2008/03/solution-vs-solid-state-mas-nmr.html
http://u-of-o-nmr-facility.blogspot.de/2007/11/magic-angle-spinning.html
http://u-of-o-nmr-facility.blogspot.de/2010/03/household-dust-bunnies.html
http://u-of-o-nmr-facility.blogspot.de/2011/12/13-c-nmr-of-delicious-christmas-treat.html

A set of lectures that give a fuller introduction to NMR
http://www-keeler.ch.cam.ac.uk/lectures/Irvine/
https://www.youtube.com/watch?v=nM7jQFhrvR0&list=PLE20foNk9J6L1dh9X27RaPiaul8_7wrAY

Part I of our recent attempts to understand collagen flexibility (Part II is being prepared…)
http://www.nature.com/articles/srep12556

Twitter handle @selkie_upsilon

 

Science at Cambridge: Chemistry

UniversityWhile at sixth form, I attended one of the Cambridge subject masterclasses for Natural Sciences – which gave me the opportunity to learn about the course and take part in lectures and lab classes at the university. At the time, I was only just starting to consider Cambridge as somewhere to study – it was only once I had specialised in science and maths subjects at A level that I began to stand out academically.

After the subject masterclass, I attended a Cambridge Open Day, where I had the opportunity to visit Murray Edwards College for the first time. Having spent most of the day visiting the more traditional colleges in town, the college was very refreshing with its more modern outlook and beautiful surroundings and I realised that I had finally found somewhere I really could fit in.

Natural Sciences is one of the most flexible science degrees – and this is what really attracted me to it. Having the option to delay picking my favourite subject for a couple of years was definitely one advantage, and employers also appreciate the broader understanding you gain of all science subjects. I have now chosen to specialise in Chemistry, and am particularly interested in organic chemistry since you can really understand why reactions happen and predict methods of synthesising new, useful molecules.

3D Kate Prescott rowingChemistry also has many practical applications across so many different industries. The pharmaceutical industry needs chemists to design and synthesise new drugs; the oil and gas industry wants to develop new methods of improving fuels by modifying their chemical composition; the engineering industry needs to understand how materials behave and react under different conditions; and so on. Therefore, Chemistry has the potential to improve so many aspects of our lives – in everything from the food we eat to the cleaning products in our bathrooms, and this is something I really love about my subject.

However, the more I learn the more ‘why’ and ‘how’ questions spring to mind. It’s amazing – you can keep delving deeper and deeper into a subject, trying to understand exactly how the world around us works. For example, if two molecules react, one can ask ‘why did one functional group react in preference to another?’ – which requires balancing several different kinetic and thermodynamic factors such as the relative reactivity of each group, stability of the possible products and the shape of the molecule. But then we could ask, ‘how does this form a new chemical bond?’ – requiring an understanding of electronic interactions, leading into yet more questions. Eventually, one can get down to mathematical descriptions of electrons and their energies – quantum mechanics, and a level at which Chemistry and Physics interact.

I would really encourage GCSE and A level students to continue studying science. Science at university is so much more exciting than at school and exams become less about memorising textbooks and more about applying our understanding to different situations. If you love to question everything and want to study a subject with practical applications, then science could be for you.

Kate Prescott
Undergraduate student

School Winner: The Quantum World

3C Alice Turnock photoWinning Entry George AbbotSchoolSince listening to Johnjoe McFadden and Jim Al-Khalili discuss their book ‘Life on the Edge: The Coming of Age of Quantum Biology’ at Surrey University last October, I’ve been immensely fascinated by the way that quantum mechanics, despite only affecting the very small, can underpin science and even explain how our bodies work.

In the early twentieth century, scientists were thrown, for they had thought they understood physics. The laws of quantum mechanics don’t obey Newtonian laws, therefore many were sceptical of this new field. Despite still lacking understanding of the mechanisms of quantum mechanics today, it has now been suggested that events on the quantum scale can have wider implications on the observable universe.

Whilst the field of quantum biology may sound unfamiliar, it was first established by Per-Olov Löwdin in 1963, who suggested that mutations in DNA may be explained by quantum tunnelling. DNA’s double helix is held together by hydrogen bonds between base pairs on nucleotides. As a hydrogen atom joins the two strands of DNA, it can determine whether or not a gene mutates. Furthermore, a singular hydrogen atom is vulnerable to quantum weirdness, due to its small size.

Löwdin proposed that, as the hydrogen atom is normally situated closer to one nucleotide than another, mutations may occur when the hydrogen atom moves by quantum tunnelling to be situated closer to the other nucleotide, and therefore be ‘wrongly’ positioned. Mcfadden and Al-Khalili developed this idea using the superposition principle. This would suggest that before being observed, the hydrogen atom would be in both positions at the same point in time (thus mutated and not mutated). In the presence of an observer, the hydrogen atom would take up a localised position, and a mutation would occur if this was closer to the ‘wrong’ nucleotide.

Whilst undoubtedly perplexing, quantum tunnelling is perhaps best described with an analogy. If you were to kick a ball up a steep hill, you would expect it to reach a point below the peak of the hill before rolling back down. Quantum tunnelling suggests that the ball would instead be able to ‘tunnel’ through the hill, ending up on the opposite side.

Understanding genetic mutations would allow us to prevent and control them. Mcfadden and Al-Khalili are in the process of testing their theory, and have deliberated experiments that involve the comparison of regular DNA against modified DNA, where hydrogen atoms are replaced with deuterium atoms. If their theory on genetic mutation is correct, then the modified DNA would mutate significantly less than regular DNA, for the deuterium would be much less likely to move by quantum tunnelling due to its greater size.

Whilst the results of the experiments are far away, the possibility of such a medical advance is hugely exciting. 4 in 10 people in the UK will be diagnosed with cancer over their lifetime, and there were around 162,000 deaths from cancer in 2012. Being able to understand quantum tunnelling in relation to genetic mutation has the potential to save millions of lives, and assist greatly in medical progression in helping to treat cancer.

“If quantum mechanics hasn’t profoundly shocked you, you haven’t understood it yet” (Bohr), as we continue to be shocked by the quantum world, we will continue to develop understanding of more aspects of life.

Alice Turnock
Year 12, George Abbot School

My name is Alice Turnock and I study chemistry, biology, mathematics and English literature at George Abbot school in Guidlford. I am hoping to study medicine next year and writing a blog entry allowed me to research and explore a concept this is extremely relevant. 

In my spare time I enjoy reading and spending time with friends.