String Theory is a Mystery

[Excerpt from an Introduction

of The Little Book of String Theory

by Steven G. Gubser, a theoretical physicists

and professor at Princeton University.]

String theory is a mystery.

It's supposed to be the theory of everything.

But it hasn't been verified experimentally.

And it's so esoteric.

It's all about extra dimensions,

quantum fluctuations, and black holes.

How can that be the world?

Why can't everything be simpler?

String theory is a mystery.

It's practitioners (of which I am one)

admit they don't understand the theory.

But calculation after calculation yields 

unexpectedly beautiful connected results.

One gets a sense of inevitability

from studying string theory.

How can this not be the world?

How can such deep truths

fail to connect to reality?

String theory is a mystery.

It draws many talented graduate students

away from other fascinating topics,

like superconductivity, that already

have industrial applications.

It attracts media attention

like few other fields in science.

And it has vociferous detractors

who deplore the spread of its influence

and dismiss its achievements

as unrelated to empirical science.

Briefly, the claim of string theory

is that the fundamental objects

that make up all matter

are not particles, but strings.

Strings are like little rubber bands,

but very thin and very strong.

An electron is supposed 

to be actually a string,

vibrating and rotating

on a length scale too small

for us to probe even with the most 

advanced particle accelerators to date.

In some versions of string theory,

an electron is a closed loop of string.

In others, it is a segment of string,

with two endpoints...

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'This book offers a very nice short introduction

to some of the basic ideas and implications

of string theory. Gubser knows his subject.'

                            John H. Schwarz

                  California Institute of Technology

                 

'Steve Gubser has written 

an engaging and thought-provoking account

of whar was achieved in physics in the last century

and how physicists are seeking to go farther

in the ambitious framework known as string theory.

This is one of the most thoughtful books

on this much-discussed topic, and readers

will find much to ponder.'

                               Edward Witten

                     Institute for Advanced Study, Princeton

'This is an engaging 

and concise introduction

to the main ideas in string theory. 

Gubser  gives us a quick tour 

of the basis of laws in physics

as we understand them today,

and then demonstrate 

how string theory 

seeks to go beyond them.

He serves as an artful and attentive guide,

as the reader explores the mysteries

of quantum mechanics, 

black holes, strings, 

branes, supersymmetry,

and extra dimensions 

in the pages of this book.'

                        Juan Maldacena

              Institute for Advanced Study, Princeton