Searching for the ultimate particle

What is the course about?

The word atom derives from the Greek "a tomos", which literally means "not cuttable". The ancient Greek philosopher Democritus theorised around 400 BCE that all matter was composed of tiny indivisible particles, the atoms. Largely neglected as a theory for many centuries, atomism enjoyed a revival in the 17th century in the work of the chemist John Dalton. Building on the refinements of the theory introduced by Dalton, physicists such as Thomson and Rutherford subsequently came to realise that the "atoms" themselves had internal structure, leading to the discovery of electrons, protons and neutrons, and ultimately to quarks. Physicists now think that electrons and quarks are the true "atoms" in the sense of having no internal structure, but developments in field and string theory may suggest that even this is not the end of the search for the ultimate particle. In this course we will examine how the concept of the ultimate particle has shaped physics over the past 2400 years.

What will we cover?

- The earliest theories of the atom
- Emerging evidence for the atom in the nineteenth century
- Late nineteenth and early twentieth century investigation of the internal structure of the atom
- From simplicity back to complexity in our understanding of the smallest particles
- The ultimate particle?
- Unanswered questions.

What will I achieve?
By the end of this course you should be able to...

- Describe how the concept of the atom came into being two and a half thousand years ago
- Explain how developments in chemistry in the nineteenth century led to a revival of the concept of the atom
- Identify the key empirical research which led to the discovery of the internal structure of the atom in the late 19th and early 20th century
- Describe how particle accelerator experiments displayed a plethora of new particles, but resulted in the realisation that all of these could be explained in terms of just six fundamental particles, the quarks
- Identify the questions which remain in the search for the ultimate particle and how these might be answered by new physics such as string theory or quantum loop gravity.

What level is the course and do I need any particular skills?

The course is suitable for beginners, though some knowledge of physics may be useful. No prior knowledge of physics or mathematics is required, but the course is designed to be of interest to those who have studied these areas as well. A good grasp of English is needed to be able to fully participate in class.

How will I be taught, and will there be any work outside the class?

You will be taught in a number of different ways including presentations with visual examples, discussions and group work. Work outside class will be optional.

Are there any other costs? Is there anything I need to bring?

There are no additional costs. If you wish to take notes you will find it useful to have a pen and paper, but the Powerpoints will be made available online.

When I've finished, what course can I do next?

For other Science courses, please check the City Lit website: Science & Nature.