Supernovas, Dark Energy, and an Accelerating Universe:

What Next?

Saul Perlmutter

Lawrence Berkeley National Laboratory

Abel 370: deep space image

The Thinker

Basic concepts

Me and audience

Sun 8 minutes ago

Nearest star & earth orbit

Nearest galaxy & first evidence of humans

Nearest clusters & dinosaurs

Abel 370: deep space image

Basic concepts: expanding universe

Picture of Einstein

Einstein 1920 (3 years after)

Prism picture

Frauenhoffer’s spectrum of sun

Through prism

Through prism, redshifted

Doppler shift picture

Object receding:

Long RED waves

Object approaching:

Short BLUE waves

Hubble’s original Hubble diagram

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How much is this expansion?

50 km/sec/Mpc

How much growth is this?

I grow an angstrom/year

But –in fact–

things that are bound don’t expand. Photons do!

How fast is this expansion?

Basic concepts: Redshift

Stretched wavelengths

Basic concepts: Standard Candle

Hubble’s original Hubble diagram

Candles

Basic concepts: Age of Universe

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age of the universe if it hadalways expanded at today’s rate

distance betweengalaxies is growing,but slower, if theuniverse is decelerating

age of theuniverse

Age from H0

Future possibilities: expand/collapse

Basic concepts

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FAINTER(Farther)(Further back in time)

EmptyMore redshift

= Faster expansion in past= Expansion is slowing

= More mass in universe

FiniteBorderline

Picture of accretion on WD star

lightcurve MPEG movie

3-panel MPEG movie

SNe Ia lightcurves (matched)

Through prism

3-panel MPEG movie

Problems with SNe Ia

Strategy (simple)

CTIO site

CTIO 4m dome

Inside CTIO 4m

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Before/after & HST

Strategy with world

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FAINTER(Farther)(Further back in time)

EmptyUniverseEventuallyRecollapses

FiniteBorderline

Our data on Hubble diagram

UniverseEventuallyRecollapses

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FAINTER(Farther)(Further back in time)

SupernovaCosmologyProject

Calan/TololoSurvey

relative brightness

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HIF

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The Implications of an Accelerating Universe

Future possibilities: expand/collapse

Future with accelerating universe

Accelerating Universe

The Implications of an Accelerating Universe

Composition of the Cosmos

DarkEnergy:65%

DarkMatter:30%

Montage of Magazine covers

Breakthrough of the Year:

Quotes from Theorists

November 30, 1999

“SNAP”: SuperNova

Acceleration Probe

Assembling SNAP

Movie courtesy of Hytec

SNAP Hubble diagram

N.Y. Times weighs in on Dark Energy

April 10, 2001

Future with accelerating universe

Accelerating Universe

Expansion History of the

Universe

The Expansion History of the Universe

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Quinten Quartet

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Hubble diagram of our data

Time Magazine weighs in on Dark Energy

Time Magazine 4/16/01

Telescope Assembly

Movie courtesy of Hytec

SNAP

Picture of orbiting HST

New Yorker cartoon: chicken little

Extrapolate age from HO

How to measure cosmology