einsteins ballerina

40
Einsteins Ballerina – the discovery of gravitational waves – Gerco Onderwater

Upload: phungtu

Post on 31-Dec-2016

227 views

Category:

Documents


1 download

TRANSCRIPT

Page 1: Einsteins Ballerina

Einsteins Ballerina– the discovery of gravitational waves –

Gerco Onderwater

Page 2: Einsteins Ballerina

2/17/16 | 2

The plan ...

Before we had gravity

Newton's universal gravity

Einstein's dynamical gravity

LIGOs result

Gerco Onderwater, 16 February 2016

Page 3: Einsteins Ballerina

2/17/16 | 3

Recording patterns

Gerco Onderwater, 16 February 2016

Page 4: Einsteins Ballerina

2/17/16 | 4

Astronomy & telescopes

Gerco Onderwater, 16 February 2016

Page 5: Einsteins Ballerina

2/17/16 | 5

Moon

Gerco Onderwater, 16 February 2016

Page 6: Einsteins Ballerina

2/17/16 | 6

Sun

Gerco Onderwater, 16 February 2016

Page 7: Einsteins Ballerina

2/17/16 | 7

Planets & Stars

Gerco Onderwater, 16 February 2016

Page 8: Einsteins Ballerina

2/17/16 | 8

Tycho Brahe

Gerco Onderwater, 16 February 2016

Page 9: Einsteins Ballerina

Keplers model

Johannes Kepler (1571-1630)Mysterium Cosmographicum (1596)planets move in elliptical orbits, not circles. Why?

Nicolaus Copernicus (1473-1543)De revolutionibus orbium coelestium (1543)sun at the center of the universe?

Gerco Onderwater, 16 February 2016

Galileo Galilei (1564-1642)Dialogo sopra i due massimi sistemi del mondo (1632)some force keeps planet in orbit

Page 10: Einsteins Ballerina

Enter Newton

Gerco Onderwater, 16 February 2016

Isaac Newton (1642-1727)Philosophiæ Naturalis Principia Mathematica (1687)laws of motion, universal gravition, mathematics

2/17/16 | 10

Page 11: Einsteins Ballerina

2/17/16 | 11

Gerco Onderwater, 16 February 2016

Page 12: Einsteins Ballerina

What about light?

James Clerk Maxwell (1831-1879)A Dynamical Theory of the Electromagnetic Field (1865)unifies electricity, magnetism, and light; introduces c

2/17/16 | 12

Gerco Onderwater, 16 February 2016

Page 13: Einsteins Ballerina

Interferometer

2/17/16 | 13

Gerco Onderwater, 16 February 2016

Page 14: Einsteins Ballerina

2/17/16 | 14

Albert Einstein

Questions

Is gravity instantaneous?

What does light move in?

Why does Mercury not move as expected?

Gerco Onderwater, 16 February 2016

Page 15: Einsteins Ballerina

2/17/16 | 15

Galileian relativity

Postulate:

Laws of motion are thesame in all inertialframes

Result:

Absolute space &universal time

Gerco Onderwater, 16 February 2016

Page 16: Einsteins Ballerina

2/17/16 | 16

1905 : Einstein's annus mirabilis

Gerco Onderwater, 16 February 2016

Page 17: Einsteins Ballerina

2/17/16 | 17

Special relativity

First postulate : the laws of physics have the sameform in all inertial reference frames

Second postulate : light moves through empty spacewith a definite speed c independent of the speed of thesource or the observers

OK!

Weird ...

Gerco Onderwater, 16 February 2016

Page 18: Einsteins Ballerina

2/17/16 | 18

Some consequences of SR

time dilation : moving clocks run slower as seen by astationary observer, time slows down

length contraction : length along the direction ofmotion is measure to be slower, space contracts

c : nothing can travel faster than light

E = mc² : mass is a form of energy

Gerco Onderwater, 16 February 2016

Page 19: Einsteins Ballerina

2/17/16 | 19

Gerco Onderwater, 16 February 2016

Page 20: Einsteins Ballerina

2/17/16 | 20

1915 : General relativity

Postulate : accelerated motion and being at rest ingravitational field equivalent

Gerco Onderwater, 16 February 2016

Page 21: Einsteins Ballerina

2/17/16 | 21

Consequences of GR

Free fall = inertial motion (no forces felt)

Gerco Onderwater, 16 February 2016

Page 22: Einsteins Ballerina

2/17/16 | 22

Consequences of GR

Space-time dynamically affected by mass

Light bends in gravitational field

Black holes

Expanding universe

Gravitational waves

Eddington 1919

Cygnus X-1 ~1990

Lemaître 1927

Gerco Onderwater, 16 February 2016

Page 23: Einsteins Ballerina

2/17/16 | 23

Universe born in “Big Bang” 14 billion years ago

1929 : Hubble observes redshift

Gerco Onderwater, 16 February 2016

Page 24: Einsteins Ballerina

2/17/16 | 24

1965 : Big Bang afterglow detected

Radio signal created as light

380,000 years after Big Bang

Gerco Onderwater, 16 February 2016

Page 25: Einsteins Ballerina

2/17/16 | 25

Cosmic Microwave Background

Gerco Onderwater, 16 February 2016

Page 26: Einsteins Ballerina

2/17/16 | 26

Binary Stars

First detected by Giovanni Battista Riccioli (1650)

GR prediction

Indirect proof of gravitational waves

Hulse & Taylor

PSR B1913+16

Gerco Onderwater, 16 February 2016

Page 27: Einsteins Ballerina

2/17/16 | 27

Pirouette

PSR B1913+16Wait for 300M years

Gerco Onderwater, 16 February 2016

Page 28: Einsteins Ballerina

2/17/16 | 28

LIGO

Light Interferometer Gravitational wave Observatory

Cofounded in 1992 by Kip Thorne, Ronald Drever, Rainer Weiss

Collaboration : ±1000 scientists / 90+ institutes / 15 countries

Mission : directly observe gravitational waves of cosmic origin

Started in 2002, upgraded in 2015

Two stations : Livingston (LA) & Hanford (WA), 3000km apart

Sensitive to colliding/coalescing binary systems (neutron stars,black holes), supernovae, rotating neutron starts, …, Big Bang

Gerco Onderwater, 16 February 2016

Page 29: Einsteins Ballerina

2/17/16 | 29

LIGO principle

Gerco Onderwater, 16 February 2016

Page 30: Einsteins Ballerina

2/17/16 | 30

LIGO optics

Seismic noise reduced by 10,000,000,000

Gerco Onderwater, 16 February 2016

Page 31: Einsteins Ballerina

2/17/16 | 31

LIGO Hanford (WA)

4km

Gerco Onderwater, 16 February 2016

Page 32: Einsteins Ballerina

2/17/16 | 32

LIGO Livingston (LA)

Gerco Onderwater, 16 February 2016

Page 33: Einsteins Ballerina

2/17/16 | 33

GW150914 / 14.09.2015 @ 09:50:45 UTC

Gerco Onderwater, 16 February 2016

Page 34: Einsteins Ballerina

2/17/16 | 34

GW150914 / 14.09.2015 @ 09:50:45 UTC

Gerco Onderwater, 16 February 2016

Page 35: Einsteins Ballerina

2/17/16 | 35

Signal & Interpretation

Peak strain of 1.0 × 10−21 → 1/1,000 of rp / 4km

Black-hole merger, ~30 solar masses each, ~150km diameter

3 solar masses radiated → 3.6×1049 W (= 50x light in universe)

Distance = 1.3Gly (1.26x1025 m)

(= 27l on earth volume; 1ml / Atlantic ocean; 1 grain / IJsselmeer)

Page 36: Einsteins Ballerina

2/17/16 | 36

Fake rate : 1 in 203,000 years

Gerco Onderwater, 16 February 2016

Page 37: Einsteins Ballerina

2/17/16 | 37

Reach

Increase sensitivity → cubedincrease in #candidates

Study strong gravity → new!

Study star formation → new options

New tool!Study very early universe →otherwise inaccessible

Gerco Onderwater, 16 February 2016

Page 38: Einsteins Ballerina

2/17/16 | 38

LIGO & Beyond

Gerco Onderwater, 16 February 2016

Page 39: Einsteins Ballerina

2/17/16 | 39

Gerco Onderwater, 16 February 2016

Page 40: Einsteins Ballerina