the age of the universe - amazon s3 · into a type ia supernova . credit: nasa, esa, and a. riess...

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THE AGE OF THE UNIVERSE CAROLIN CRAWFORD GRESHAM PROFESSOR OF ASTRONOMY NASA/ESA/Hubble Heritage

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Page 1: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

THE AGE OF THE UNIVERSE

CAROLIN CRAWFORD

GRESHAM PROFESSOR OF ASTRONOMY

NASA/ESA/Hubble Heritage

Page 2: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

NASA/NOAA/GSFC/Suomi NPP/VIIRS/Norman Kuring

Page 3: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Linda Bruce

Lord Kelvin

1824 - 1907

Page 4: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess
Page 5: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

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Daughter material

Parent material

time

Page 6: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Arthur Holmes

1890 - 1945

Page 7: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

NASA

Page 8: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Clair Patterson

1922-1995

F. Antonucci, M. Angelini, & F. Tagliani, ADARA Astrobrallo

Page 9: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

NASA/ESA/Hubble Heritage

Page 10: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Alan Friedman (Averted Imagination)

Page 11: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess
Page 12: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Chris Hetlage

cosmological constant

LeMaitre Friedmann

Page 13: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Edwin Hubble

1889 - 1953

2

d π 4

Luminosity Flux

Page 14: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

combined measurements of

distances to and

velocities of

the ‘spiral nebulae’

all galaxies are receding

Stephen Leshin

Page 15: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Stephen Leshin

Hubble’s Law

Page 16: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

uniform expansion of space

Galaxy twice as far away has moved twice as far/as fast

Page 17: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

– the universe is expanding

– it was smaller in the past

Big Bang !

Russell Croman

A galaxy a distance d away

moving away from us at velocity v

has taken a time of ~ d/v to travel to that point

Page 18: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess
Page 19: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

NASA

Page 20: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

NASA/ESA/Reiss (STScI/JHU)

Page 21: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

NASA. ESA, Hubble Heritage (STScI/AURA)

Page 22: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

NASA. ESA, Hubble Heritage (STScI/AURA)

Page 23: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Martin Pugh

• Luminosity of a star depends on its mass

Page 24: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Martin Pugh

• Luminosity of a star depends on its mass

• Age of a star depends on its mass

Page 25: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Martin Pugh

• Luminosity of a star depends on its mass

• Age of a star depends on its mass

Faintest ►lowest-mass ► oldest stars

Page 26: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Martin Pugh

73 km s-1 per Megaparsec

Page 27: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

NASA/ESA/ Rigby, Sharon, Gladders & Wuyts

“matter tells space how to curve,

and space tells matter how to move”

Wheeler

Page 28: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Cre

NASA/WMAP science team

Page 29: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Cre

NASA/WMAP science team

Page 30: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

recollapsing

Universe

present

past

future

Page 31: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

recollapsing

Universe

open

Universe

present

past

future

Page 32: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

recollapsing

Universe

open

Universe

present

past

future

critical

Universe

Page 33: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

an important cosmological parameter...

density parameter of the Universe

Ω = / c

where c is the critical density of matter needed to close the

Universe

if Ω > 1 closed Universe

universe will eventually stop expanding, then collapse

If Ω < 1 open Universe

the universe expands forever

Page 34: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

recollapsing

Universe

open

Universe

present

past

future

Ω<1 Ω>1 Ω=1

critical

Universe

Page 35: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

–200μK +400μK

The cosmic microwave background

NASA/WMAP science team

Page 36: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

NASA/WMAP science team

Page 37: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

NASA/WMAP science team

Page 38: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

recollapsing

Universe

open

Universe

present

past

future

Ω<1 Ω>1 Ω=1

critical

Universe

size of CMB

fluctuations shows

we live in a

flat (‘critical’)

universe

all the

matter + radiation

in the Universe is

only 25% of what is

required

Page 39: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Baryonic mass of cluster is determined from the

amount of light radiated – at all wavelengths

Total gravitating mass of cluster (including dark

matter) obtained through many methods (X-rays,

galaxy motions, gravitational lensing)

NASA/ESA/J Richard & JP Kneib

Page 40: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Dean Rowe

the observed baryonic fraction

fb = baryonic mass / total mass

Page 41: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Observations

of nearby

clusters

show fb~0.12

fb

Radius in cluster

Allen et al

Page 42: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Observations of clusters of galaxies tell us the ratio of

ordinary mass / total (dark+ordinary) mass ~ 0.12

calculations of primordial synthesis fix how much

ordinary matter was created in the Big Bang

so we know the total amount of matter in the

Universe

Palomar-Quest Survey Team

Page 43: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

baryon fraction should be the same all across the Universe

change reference cosmology used to derive these

observables until the fraction of baryonic mass is

the same for all clusters

Allen et al

Page 44: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Supernova type 1a

Page 45: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Sun-like

star

expands to

red giant

sheds outer

layers

cools and

contracts to

white dwarf

...but if it can

accrete mass from

a binary partner

once over 1.4 Msun

it will suddenly explode

into a type Ia supernova

Page 46: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Sun-like

star

expands to

red giant

sheds outer

layers

cools and

contracts to

white dwarf

...but if it can

accrete mass from

a binary partner

once over 1.4 Msun

it will suddenly explode

into a type Ia supernova

Page 47: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Credit: NASA, ESA, and A. Riess (STScI)

Page 48: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Rela

tiv

e brig

htness

Brighter supernovae

fade more

slowly…

Kim et al 1997

Days after peak brightness

Supernova

explosion

Page 49: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

velocity

dis

tance

distant supernovae are:

dimmer and so

further away

than expected

Page 50: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

distance expected

distance measured

v

Page 51: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

The supernova results show that:

• the expansion of the Universe is speeding up

• this acceleration started about 6 billion years ago

– the Universe is younger than we thought

– gravity does not control the Universe

Johannes Schedler (Panther Observatory)

Perlmutter Schmidt Riess

Page 52: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

All matter (+radiation) accounts for only

¼ of the mass-energy density of the Universe

The other ¾ must take the form of energy

we call this ‘dark energy’...

...and this ‘dark energy’ is responsible for the

accelerated expansion of the Universe

Page 53: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Dark energy

75%

Visible matter

5%

Dark matter

20%

Page 54: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

The attractive force of gravity

is a property of matter

accelerating

Universe

The repulsive force of dark energy

is a property of space

Thus as the universe expands,

dark energy

begins to dominate over gravity

Page 55: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

recollapsing

Universe

open

Universe

present

past

future

Ω<1 Ω>1 Ω=1

critical

Universe

accelerating

Universe

Page 56: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

The cosmological

constant

What is the dark energy?

Page 57: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

The cosmological

constant

What is the dark energy?

The vacuum

energy of

space

Page 58: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

The cosmological

constant

What is the dark energy?

The vacuum

energy of

space

Quintessence

Page 59: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

NASA/CXC/M.Weiss

Page 60: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

Hubble HUDF team

13.772±0.059 billion years

Page 61: THE AGE OF THE UNIVERSE - Amazon S3 · into a type Ia supernova . Credit: NASA, ESA, and A. Riess (STScI) s ... Johannes Schedler (Panther Observatory) Perlmutter Schmidt Riess

EXOPLANETS…

…AND HOW TO FIND THEM

WED 6TH

MARCH 1PM