Upload
others
View
0
Download
0
Embed Size (px)
Citation preview
The Universe in a (Pretty Big) Box:From Cells to Galaxies Using Super-Computers
Diego Muñoz Michael Long
Amanda Peters Randles
Thursday, October 25, 12
Thursday, October 25, 12
Thursday, October 25, 12
Thursday, October 25, 12
Thursday, October 25, 12
Thursday, October 25, 12
Thursday, October 25, 12
The Universe in a (Pretty Big) Box:From Cells to Galaxies Using Supercomputers
Part I 14 Billion Years of History told by 10 Billion
Particles: A Simulated Universe
Diego Muñoz Harvard-Smithsonian Center for AstrophysicsDepartment of Astronomy, Harvard University
Thursday, October 25, 12
Computational power Computational methods
Image source: www.clker.com, Public Domain
Thursday, October 25, 12
Computational power Computational methods
Image source: www.clker.com, Public Domain
Thursday, October 25, 12
Computational power Computational methods
Larger, faster computers Better, more efficient techniquesand approximations
Image source: www.clker.com, Public Domain
Thursday, October 25, 12
Gravity
Sir Isaac Newton, portrait by Sir Godfrey Kneller
GRAVITY is one of the fundamental forces of the Universe, that is, it originates with the universe itself.
However, it was not understood until Isaac Newton’s Principia Matematica (1687). The term originates from the Latin gravitas, which means weight.
Thursday, October 25, 12
Gravity
Sir Isaac Newton, portrait by Sir Godfrey Kneller
GRAVITY is one of the fundamental forces of the Universe, that is, it originates with the universe itself.
However, it was not understood until Isaac Newton’s Principia Matematica (1687). The term originates from the Latin gravitas, which means weight.
Thursday, October 25, 12
Gravity
"The Blue Marble" photograph of Earth, taken from Apollo 17. Source: Wikipedia
Image credit: NASA / JPL-Caltech / R. Hurt. Source: Wikipedia
Thursday, October 25, 12
GravityAsteroid Discovery 1980-2010. Credit: Scott Manley
Thursday, October 25, 12
Gravity
Whi
rlpoo
l Gal
axy/
M51
a . A
utho
r: N
AS
A an
d E
urop
ean
Spa
ce A
genc
y
Thursday, October 25, 12
Gravity at Cosmic Scales
HST Image of NGC 4414 /Image source: wikimedia commons
A galaxy...
Thursday, October 25, 12
Gravity at Cosmic Scales
HST Image of NGC 4414 /Image source: wikimedia commons
1000000000000000000 kmor 1 quintillion km
A galaxy...
Thursday, October 25, 12
Gravity at Cosmic Scales
HST Image of NGC 4414 /Image source: wikimedia commons
A galaxy...
Thursday, October 25, 12
Gravity at Cosmic Scales
Burrell Schmidt telescope image of the Virgo cluster. Credit Chris Mihos et al.using the /Image source: wikimedia commons
A cluster of galaxies...
Thursday, October 25, 12
Gravity at Cosmic Scales
Burrell Schmidt telescope image of the Virgo cluster. Credit Chris Mihos et al.using the /Image source: wikimedia commons
100000000000000000000 kmor 100 quintillion km
A cluster of galaxies...
Thursday, October 25, 12
Thursday, October 25, 12
6 sextillion km
0.7 sextillion km
0.15 sextillion km
Thursday, October 25, 12
Gravity
Sir Isaac Newton, portrait by Sir Godfrey Kneller
Newton postulated, the the gravitational force between two bodies of masses m1 and m2 has a magnitude of
Thursday, October 25, 12
Gravity
Sir Isaac Newton, portrait by Sir Godfrey Kneller
Newton postulated, the the gravitational force between two bodies of masses m1 and m2 has a magnitude of
m1 m2
Thursday, October 25, 12
Gravity
Sir Isaac Newton, portrait by Sir Godfrey Kneller
Newton postulated, the the gravitational force between two bodies of masses m1 and m2 has a magnitude of
m1 m2
Thursday, October 25, 12
Gravity
Sir Isaac Newton, portrait by Sir Godfrey Kneller
Newton postulated, the the gravitational force between two bodies of masses m1 and m2 has a magnitude of
m1 m2 r
Thursday, October 25, 12
Gravity
Sir Isaac Newton, portrait by Sir Godfrey Kneller
Newton postulated, the the gravitational force between two bodies of masses m1 and m2 has a magnitude of
m1 m2 r
where r is the distance between the bodies and G is the universal gravitational constant.
Thursday, October 25, 12
Gravity
Image license: Stock photo, photo.xchng Image ID: 909780
Thursday, October 25, 12
Gravity
Image license: Stock photo, photo.xchng Image ID: 909780
Thursday, October 25, 12
Gravity
Image license: Stock photo, photo.xchng Image ID: 909780
Thursday, October 25, 12
Gravity
Image license: Stock photo, photo.xchng Image ID: 909780
Earth
Moon
Thursday, October 25, 12
Gravity
Image license: Stock photo, photo.xchng Image ID: 909780
Earth
Moon
Thursday, October 25, 12
Gravity
Image license: Stock photo, photo.xchng Image ID: 909780
Earth
Moon
m1
m2
Thursday, October 25, 12
Gravity
Image license: Stock photo, photo.xchng Image ID: 909780
Earth
Moon
m1
m2
Thursday, October 25, 12
Questions?
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
a “particle”
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
1
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
1
2
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
1
21
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
1
21
3
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
1
21
23
3
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
1
21
23
3
4
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
1
21
23
3
4
4
5
6
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
1
21
23
3
4
4
5
6
5
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
1
21
23
3
4
4
5
6
5
8 79
10
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
1
21
23
3
4
4
5
6
5
8 79
10
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
1
21
23
3
4
4
5
6
5
8 79
10for N particles:
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
1
21
23
3
4
4
5
6
5
8 79
10
Gravitational systems require an enormous amount of operations
for N particles:
Thursday, October 25, 12
Human Brain versus Computer
Thinking Man by Rodin
Thursday, October 25, 12
Human Brain versus Computer
Thinking Man by Rodin
1 second per operationfor operations
Thursday, October 25, 12
Human Brain versus Computer
Thinking Man by Rodin
(10 billion)2/2 seconds to calculate gravity for a Galaxy = 1 trillion years
1 second per operationfor operations
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
• Computers help us perform large numbers of operations
• Super-computers allow us to carry the operations out simultaneously
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
• Computers help us perform large numbers of operations
• Super-computers allow us to carry the operations out simultaneously
• Super-computers allow us to calculate approximate solutions in an efficient manner.
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
• Computers help us perform large numbers of operations
• Super-computers allow us to carry the operations out simultaneously
• Super-computers allow us to calculate approximate solutions in an efficient manner.
CAN WE CALCULATE GRAVITY APPROXIMATELY?
Thursday, October 25, 12
Why Computers?
Thursday, October 25, 12
Why Computers?
5 = x +3
Thursday, October 25, 12
Why Computers?
5 = x +3x = 2
Thursday, October 25, 12
Why Computers?
Thursday, October 25, 12
Why Computers?
x = 1 2x
Thursday, October 25, 12
Why Computers?
x = 1 2x
Thursday, October 25, 12
Why Computers?
x = 1 2x
x = 0?
Thursday, October 25, 12
Why Computers?
x = 1 2x
x = 0? 0 = 1
Thursday, October 25, 12
Why Computers?
x = 1 2x
x = 0? 0 = 1x = 1?
Thursday, October 25, 12
Why Computers?
x = 1 2x
x = 0? 0 = 1x = 1? 1 = 1/2
Thursday, October 25, 12
Why Computers?
x = 1 2x
x = 0? 0 = 1x = 1? 1 = 1/2
0 1
Thursday, October 25, 12
Why Computers?
x = 1 2x
x = 0? 0 = 1x = 1? 1 = 1/2
0 10.5
Thursday, October 25, 12
Why Computers?
x = 1 2x
x = 0? 0 = 1x = 1? 1 = 1/2
0 1
x = 0.5?
0.5
Thursday, October 25, 12
Why Computers?
x = 1 2x
x = 0? 0 = 1x = 1? 1 = 1/2
0 1
x = 0.5? 0.5 = 0.707...
0.5
Thursday, October 25, 12
Why Computers?
x = 1 2x
x = 0? 0 = 1x = 1? 1 = 1/2
0 1
x = 0.5? 0.5 = 0.707... x = 0.6411?
0.5
Thursday, October 25, 12
Why Computers?
x = 1 2x
x = 0? 0 = 1x = 1? 1 = 1/2
0 1
x = 0.5? 0.5 = 0.707... x = 0.6411? 0.6411 0.64122...
0.5
Thursday, October 25, 12
Why Computers?
Image credit:http://www.shiftingstates.com
until it is “good enough”...
Thursday, October 25, 12
Why Computers?
0.6411857445049 8598448620048211482366656282095719110...
x =
Thursday, October 25, 12
What is “Good Enough”?
Thursday, October 25, 12
What is “Good Enough”?
Thursday, October 25, 12
What is “Good Enough”?
In physics: the fine structure constant is known within 10 significant figures. Its relative standard of uncertainty is 0.32 parts per billion
Thursday, October 25, 12
What is “Good Enough”?
In physics: the fine structure constant is known within 10 significant figures. Its relative standard of uncertainty is 0.32 parts per billion
In astronomy: The mass of the Milky Way is known only within a 50% error: 1.0 - 1.5 billion times the mass of the Sun
Thursday, October 25, 12
Questions?
Thursday, October 25, 12
Gravity in Astrophysics
Thursday, October 25, 12
Gravity in Astrophysics
Images: HST publicly released images, hubblesite.org/newscenter
Thursday, October 25, 12
Gravity in Astrophysics
Images: HST publicly released images, hubblesite.org/newscenter
Thursday, October 25, 12
Gravity in Astrophysics
Images: HST publicly released images, hubblesite.org/newscenter
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
http://openclipart.orgoffice.microsoft.com/en-us/images/
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
Thursday, October 25, 12
Calculating Gravitational Forces with Supercomputers
Thursday, October 25, 12
...this is called domain decomposition
Thursday, October 25, 12
(Mihos & Hernquist 1996)Credit: NASA, ESA, and F. Summers (STScI) 2008
Simulation Data: Chris Mihos (Case Western Reserve University) and Lars Hernquist (Harvard University)
http://hubblesite.org/newscenter/archive/releases/2008/16/video/d/
Thursday, October 25, 12
credit: Philip Hopkins, UC Berkeley Thursday, October 25, 12
The Universe in a Box:
What is the shape of the Universe??
Thursday, October 25, 12
Sloan Digital Sky Survey http://www.sdss.org
Thursday, October 25, 12
Aquarius Simulation -- Virgo Consortium
Thursday, October 25, 12
Thursday, October 25, 12
Thursday, October 25, 12