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String theory may provide the best clues yet about how to obtain a unified theory that describes all the laws of nature, but do we even understand what string theory is?
When Subrahmanyan Chandrasekhar asked in his twenties, ‘What happens to a massive star when it runs out of fuel?’ he had little idea that it would take a generation of astronomers to find the answer.
At the level of particles, things can happen in reverse, because particles obey time-symmetric laws of mechanics. But then why does matter, which is made up of these building blocks, behave irreversibly?
Einstein challenged physics to describe “the real factual situation”. But an understanding of the very concepts that he criticized a century ago may provide the best clues yet about reality ‘out there’.
Tales of brilliant scientists and their heroic discoveries can overshadow the true nature of scientific communities, which are often dominated by battles for power and success.
Thomas Young strove to satisfy his curiosity in virtually every scientific subject and, undeterred by sceptics calling for a narrower focus, made discoveries in almost all the fields he studied.
From pioneering xerographer to innovative teacher, Georg Christoph Lichtenberg was a physicist with many skills, but perhaps most remembered will be his acerbic aphorisms.
Glycomics: like proteins and nucleic acids, carbohydrates have essential roles in the cell, but the tools to synthesize and analyse this third class of biopolymer have, until recently, lagged far behind.
Sixty years on, Erwin Schrödinger's prediction that quantum mechanics would solve the riddle of how life started has not been fulfilled. But the appeal of using quantum theory to solve the mystery persists.
Paul Dirac insisted that his approach to quantum physics was geometric not algebraic. But where is the evidence of this in his pioneering, algebra-rich papers?
An elegant orientation solution that is used by ants to get back to their nest eluded even Richard Feynman, suggesting that social insects could help to solve many of our engineering problems.
The only reality is mind and observations, but observations are not of things. To see the Universe as it really is, we must abandon our tendency to conceptualize observations as things.
The first person to carry out a modern survey of the night sky, Fritz Zwicky's astronomical observations led to a new picture of a turbulent Universe that is punctuated by violent events.
Although the laws of physics explain much of the world around us, we still do not have a realistic description of causality in truly complex hierarchical structures.
Optimization: this beguilingly simply idea allows biologists not only to understand current adaptations, but also to predict new designs that may yet evolve.
Cell doctrine: modern biology and medicine see the cell as the fundamental building block of living organisms, but this concept breaks down at different perspectives and scales.
Our persistence in placing ourselves at the top of the Great Chain of Being suggests we have some deep psychological need to see ourselves as the culmination of creation.
Ergodicity: a fundamental assumption of statistical physics — anything that can happen will happen — was thrown into question 50 years ago. Now it looks solid after all.
