Where Did Dark Matter And Dark Energy Come From?

in the early 1990s two teams of

astronomers had set out to measure just

what the universe was made of

these two teams known as the high zed

supernova search team and the supernova

cosmology project brought together

astronomers from around the globe with

the goal of charting cosmic expansion

over the life of the universe

the astronomers expected the presence of

all the matter and radiation in the

universe to act like a drag on the

expansion steadily slowing it as the

cosmos aged by measuring this

deceleration all the matter and energy

that make up the universe would be

revealed

these international collaborations

cooled on the world's mightiest

telescopes such as the eight-meter keck

telescope in hawaii and orbiting hubble

space telescope to scour the sky

their target was supernovae acting as

beacons of the distant cosmos whose

brightness as measured through our

telescopes revealed how the universe had

expanded as their light traveled for

billions of years

but the astronomers

were in

for a shock

our universe

is not slowing down

it

is speeding up

after repeatedly searching for flaws in

their observations and checking their

calculations they presented their

conclusions to a startled world

and to account for this accelerated

expansion there was something else in

the universe

something unexpected driving the cosmos

faster and faster

and whilst there must be immense

quantities of this stuff for the effect

to take place it remained and remains

totally invisible to our telescopes

whatever is out there between the stars

and galaxies accelerating the expansion

it is truly

dark

this result netted the leaders of the

experiment brian schmidt saul perlmutter

and adam reese the 2011 nobel prize in

physics and this discovery of dark

energy came at the end of a tumultuous

century

astronomers had discovered that our sun

was an ordinary star in an ordinary

galaxy nowhere in particular in an

expanding universe

shocking was the revelation that in

terms of mata all the atoms in all the

stars in all the galaxies

a little more than cosmic

bit players

all the matter we can see appeared to be

dwarfed by huge quantities of unseen

matter revealed only by its

gravitational pull

and as 1998 dawned we realized that even

this dark matter was significantly

outweighed by the presence of the newly

discovered dark energy

two vast components of the cosmos

unseeable and for millennia

undetectable

it is currently the biggest question in

cosmology

what are these new components of our

universe

how

do they work

and where did they come from

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on the 29th of may 1919 a total eclipse

of the sun passed over the southern

atlantic

two expeditions headed by british

astronomers arthur eddington and frank

dyson set off to observe this phenomenon

one team headed to brazil the other to

west africa

the expeditions were beset by problems

from faulty instruments to weather that

refused to cooperate

on the island of principe off the coast

of africa the eclipse was due at two in

the afternoon

but throughout the morning eddington had

sat in the pouring rain the sun not

peaking from behind the grey until half

an hour before the eclipse

clouds continued to cross the sky even

as it darkened eddington busied himself

changing photographic plates in the

telescope only glancing momentarily at

one of nature's most spectacular sights

would the observation be a lost cause

would all this effort be a waste of time

a few days later eddington had his

answer

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and our picture of the universe

changed

forever

the headline in the new york times

proclaimed lights or the skew in the

heavens and the little-known albert

einstein became the most famous

scientist in the world

four years earlier during the turbulent

years of the first world war einstein

had published his general theory of

relativity the culmination of a decade's

hard work relativity gave us a new

picture of gravity replacing newton's

forces with malleable space-time

during the war years relativity was an

academic curiosity but with peace

restored scientists had set out to test

the predictions of this new scientific

theory

their goal had been to measure the

locations of background stars whose

light passed close to the edge of the

sun stars that would be visible when the

immense glare of the sun was dimmed

during an eclipse

if einstein was correct the gravity of

the sun should act like a lens gently

deflecting the starlight from its

straight-line path

and on the photographic plates obtained

in brazil and africa the stars had

shifted by the predicted amount

einstein's theory

had triumphed

whilst the result made him a star

einstein thought that this gravitational

lensing had little practical consequence

stars were simply not massive enough to

use as natural telescopes to magnify the

distant universe

nothing could be there was nothing in

the universe with enough mass to have

such an effect

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or at least

as far

as he knew

in the 1930s astronomer fritz zviki was

working at the california institute of

technology

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zviki was a brilliant scientist with a

prickly personality combining geometry

and profanity he referred to his enemies

as spherical bastards implying they were

a bastard no matter which way you looked

at them

but as an original thinker zviki's mind

roamed through the mysteries of the