THE FUNDAMENTALS OF PHYSICS

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The L arge Hadron Collider is used to recreate conditions

in the moments immediately af ter the Big Bang

THE STORY OF

THE UNIVERSE

From the Big Bang to the formation of the Solar System,

Dr Stuart Clark and Dr Elizabeth Pearson reveal the birth of

the Universe and the history of its life in six chapters

T

he yea r 2009 could go dow n in
the astronomical textbooks as
the one when a revolution in our
understanding of the Universe began.
The protagonist at the centre of this
upheaval was not a person but a
machine: a space probe called Planck.
Named after the great German
physicist Max Planck, the spacecraft
was launched by the European Space
Agency that year and was tasked with
detecting the ‘blueprint’ of the
Universe – capturing a snapshot of the
seeds of the stars and galaxies that
surround us today.
Prior to its launch, cosmologists had
spent over a century constructing
mathematical theories to describe the
story of the Universe, from the earliest
moments to the present day. But
a nalysis of t he data retu r ned by Pla nck
has revealed a number of plot holes

• or ‘anomalies’ as the scientists call
  them – that don’t seem to fit the story.
  For one thing, data from Planck
  indicates that the Universe is older
  than expected by about 50 million
  years. The Universe also contains
  more of the mysterious dark matter
  and fewer atoms than previously
  thought. And while these two things
  may sound serious, in reality they are
  the least of a cosmologist’s worries.
  Much more troubling is the so-
  called ‘cold spot’ in the radiation from

the early Universe that Planck has

recorded – a region that looks

significantly colder than current

theories allow. Indeed, the

temperature pattern across the whole

Universe looks strangely lopsided.

Discoveries such as these are

shedding new light on the history of

the Universe and revealing more of the

story of how we arrived at the cosmos

we see a round us today.

CHAPTER 1: THE BIG BANG

The very moment of the Big Bang

remains shrouded in as much mystery

as ever. It’s the point at which the

Universe began – space and time were

formed and all the matter and energy

t hat we see a round us somehow ca me

into existence. Data f rom t he Pla nck

space probe indicates this happened

13.82 billion years ago. Initially, there

were no stars or galaxies, just a hot,

dense sea of particles and radiation.

Immediately after the Big Bang,

space began to expand, spreading out

matter and energy. The trouble is the

t heor y t hat we use to understa nd t he

expansion, Einstein’s Theory of

General Relativity, doesn’t work at the

extreme densities of the Big Bang, so

we are searching for a way to extend it.

The best template is quantum

theory, which deals with the physics

of the very small and provides a basis

for all the forces of nature, except

gravity. To investigate such a theory,

scientists must tu r n to t he La rge

Had ron Collider (LHC) at CER N in

Switzerland, which recreates the

conditions t hought to have been

present in the Universe a fraction of a

second after the Big Bang.

“The LHC gives us a mini-Universe

in the laboratory,” says Dr Anupam

Mazumdar, a cosmologist at the

University of Groningen. 5