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New Scientist The Collection

New Scientist The Collection Instant Expert

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New Scientist covers discoveries and ideas in science and technology that will change your life and the way you understand the world. New Scientist employs and commissions the best writers in their fields to provide in-depth but accessible coverage of the developments that matter. New Scientist: The Collection is a themed compilation of recent articles and special reports from our back catalogue, providing a book-length examination of some of the deepest questions known to humanity.

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United Kingdom
New Scientist Ltd
Back issues only

in this issue

2 min.
knowledge is power

THERE are few more satisfying things in life than getting your head around a profound idea. And if you want to understand yourself and the world around you, there is nowhere better to look for a profound idea than science. The best way to get to grips with a novel concept is to talk to an expert, but there’s rarely one around when you’re in need. This issue of New Scientist: The Collection is the next best thing: we’ve done the hard work for you. The articles in this collection started life as editions of Instant Expert, a monthly supplement in New Scientist magazine. Every month we’d ask a leading scientist to write an introductory guide to their specialist subject. We chose scientists who not only knew the topic inside out but…

4 min.
the big questions

Theoretical physicists like to ask big questions. How did the universe begin? What are its fundamental constituents? And what are the laws of nature that govern those constituents? If we look back over the 20th century, we can identify two pillars on which our current theories rest. The first is quantum mechanics, which applies to the very small: atoms, subatomic particles and the forces between them. The second is Einstein’s general theory of relativity, which applies to the very large: stars, galaxies and gravity, the driving force of the cosmos. The problem we face is that the two are mutually incompatible. On the subatomic scale, Einstein’s theory fails to comply with the quantum rules that govern the elementary particles. And on the cosmic scale, black holes are threatening the very foundations of…

4 min.
the road to unification

Many attempts have been made to reconcile Einstein’s theory of gravity with the quantum description of the other three forces of nature. The latest and most ambitious is called M-theory and it contains three radical ingredients: extra dimensions of space-time, supersymmetry, and extended objects called superstrings and membranes. 1. EXTRA DIMENSIONS One of the earliest attempts at unifying the forces of nature was made in the 1920s, when German physicist Theodor Kaluza melded Einstein’s gravitational theory with the electromagnetic theory of James Clerk Maxwell. The universe we live in appears to have four dimensions. Space has three – right-left, forwards-backwards and up-down – and the fourth is time. Kaluza rewrote Einstein’s theory as if there were five space-time dimensions. This gives the gravitational field some extra components which he thought could be interpreted…

6 min.
theory of everything

Our leading candidate for a theory of everything is known as M-theory. It grew from a merger of the two seemingly different approaches: 11-dimensional supergravity and 10-dimensional superstring theory. Could this be the final theory of everything? BRANE POWER Superstring theory had some serious shortcomings. One problem is that there is not one, but five, mathematically consistent superstring theories, each competing for the title of the theory of everything. We faced an embarrassment of riches. A second puzzle soon became apparent, too. Supersymmetry says that the universe has a maximum of 11 dimensions, yet the mathematics of superstring theory states there should be 10. What gives? And there was a related question: why stop at one-dimensional strings? Why not two-dimensional membranes which might take the form of a sheet or the surface of…

2 min.
answering the critics

The job of theoretical physicists is twofold: first, to explain what our experimental colleagues have discovered; and second, to predict phenomena that have not yet been found. The history of scientific discovery shows that progress is achieved using both methods. Quantum theory, for example, was largely driven by empirical results, whereas Einstein’s general theory of relativity was a product of speculation and thought experiments, as well as advanced mathematics. Speculation, then, is a vital part of the scientific process. When Paul Dirac wrote down his equation describing how quantum particles behave when they travel close to the speed of light, he wasn’t just explaining the electron, whose properties had been well established in experiments. His equation also predicted the hitherto undreamed-of positron, and hence the whole concept of antimatter. Such speculation is not…

5 min.
history of general relativity

Albert Einstein’s general theory of relativity is one of the towering achievements of 20th-century physics. Published in 1915, it explains that what we perceive as the force of gravity in fact arises from the curvature of space and time. Einstein proposed that objects such as the sun and Earth change this geometry. In the presence of matter and energy, space-time can evolve, stretch and warp, forming ridges, mountains and valleys that cause bodies moving through it to zigzag and curve. So although Earth appears to be pulled towards the sun by gravity, there is no such force. It is simply the geometry of space-time around the sun telling Earth how to move. The general theory of relativity has far-reaching consequences. It not only explains the motion of the planets; it can also…