Gravitational Physicsthe dynamics of spacetime

FOM, April 7, 2009 - jo@nikhef.nl

Motivation

Aim and focus

Composition of consortium

Requested positions versus aim

Coherence and added value

Outline

Einstein gravity :

Gravity as a geometrySpace and time are physical objects

8G T

Gravitation– Least understood interaction

– Large world-wide intellectual activity

– Theoretical: ART + QM, Cosmology

– Experimental: Interferometers on Earth and in space

Gravitational waves– Dynamical part of gravitation, all space is filled

– Very large energy, almost no interaction

– Ideal information carrier, almost no scattering or attenuation

– The entire universe has been transparent for GWs, all the way back to the Big Bang

Motivation

Aim and focus

Scientific promise– Direct discovery of gravitational waves

– Signals from the early Universe

– Towards gravitational wave observatories

Bundle existing strengths– (astro)particle physics: experiment and theory

– Astrophysics, astronomy and cosmology

Multi-disciplinary physics program

To achieve deep understanding of gravitation and spacetime

Focus on 3 activities

R.A. Hulse and J.H. Taylor Jr (1993)

The horizon (best orientation) for a binary system of two 10 solar mass black holes is 63 Mpc

Compare to square root of Planck time: 1445 Hz105/ cGclt NPP

For capability to study details at Planck scaleHz103.2 22 Pth

Interferometers – sensitivity

6

100 million light years

Enhanced LIGO ~2009

Advanced LIGO ~2014

LIGO today

Credit: R.Powell, B.Berger

Nikhef contributions to Virgo+ :

– Automatic Alignment electronics

– Thermal compensation simulations

– Input Mode Cleaner optics

1 ev/week –

1 ev/day expect

ed

Activity 1 - towards discovery

Probable sources

– Binary neutron star coalescence

– Binary black holes mergers, supernovae, pulsars

Horizon (Virgo+)

– BNS: 150 Mpc (optimal orientation)

– BBH: 750 Mpc (optimal orientation)

BNS Rates: (most likely and 95% interval)

– Initial Virgo (30Mpc) 1/100yr (1/500 - 1/25 yr)

– Enhanced LIGO (60Mpc) 1/10yr (1/50 - 1/2.5yr)

– 2009: Virgo+ limit (150Mpc) 1.2/yr (1/4 - 5/yr)

– 2014: Advanced detectors (350Mpc) 40/yr (8 - 160/yr)

Kalogera et al; astro-ph/0312101; Model 6

BBH and other sources rates are more difficult to predict

Astronomy: we know GW sources exist!

Activity 1 - direct discovery of GW

Design Study Proposal approved by EU within FP7Large part of the European GW community involved

EGO, INFN, MPI, CNRS, NIKHEF, Univ. Birmingham, Cardiff, Glasgow

Recommended in Aspera / Appec roadmap

– 3 spacecraft in Earth-trailing solar orbit separated by 5 x106 km.

– Measure changes in distance between fiducial masses in each spacecraft

– Partnership between NASA and ESA

– Launch date ~2018+

GW roadmap: Golden Age of Gravitational Physics

Activity 2 - GW antenna in space - LISA

RotatingNeutron Stars

Difference of 104 in wavelength:Like difference between X-rays and IR!

VIRGOLIGO

LISA

LISA will see all the compact white-dwarf and neutron-star binaries in the Galaxy (Schutz)

Complementarities of GW detectors

Is Einstein’s theory still right in these conditions of extreme gravity? Or is new

physics awaiting us?

Chandra - Each point of x-ray

light is a Black Hole!

What happens at the edge of a Black Hole?

Science goals

Dark energy and matter interact through gravity

We do not know what 95% of the

universe is made of!

What is the mysterious Dark Energy pulling the Universe apart?

Science goals

Gravitational Waves Can Escape from Earliest Moments of the Big Bang

Inflation(Big Bang plus 10-34 Seconds)

Big Bang plus 380,000 Years

gravitational waves

Big Bang plus 14 Billion Years

light

Now

What powered the Big Bang?

Science goals

Theoretical (astro)particle physics community

– GW, inflation, string theory, cosmic defects

– Jan Willem van Holten et al. (Nikhef, Leiden)

Provide templates, spectra, etc.

– Participate in Virgo – LIGO analysis Galluccio et al; Phys. Rev. Lett. 79 (970)

Activity 2: Signals from inflation and phase transitions

G. Koekoek

SRON

– LISA Pathfinder

Theoretical (astro)particle physics community

– GW, inflation, string theory, cosmic defects

Westerbork

– EPTA

NOVA

– Leiden Univ.: PTA (Levin)

– UvA: GW emission NS (Watts)

ESA – Noordwijk

– LISA coordination (Jennrich)

Leiden Univ.

– MiniGrail (Frossati)

Nikhef

– Strategic plan, Review 2007

2006GW in the Netherlands

Periodic sources analysis – GRID– VU – Nikhef – RU

Coalescing binaries – BNS, BBH– Nikhef – VU – RU

Advanced Virgo upgrade– Nikhef – VU

Early Universe – theory and analysis– Nikhef - VU

Source populations ET and LISA – RU – Nikhef – VU

All members bring in relevant experience

Consortium

Discovery

ET, LISAEarly Universe

H.J. Bulten Analysis, LISA

T. Ketel Optics

J. van den Brand Coordinator

D. Rabeling (postdoc) Discovery, ET

G. Koekoek (PhD) Theory

T. Bauer Optics

H. van der Graaf Suspension

J.W. van Holten Theory

New staff member Analysis

M. Beker (PhD) ET

S. van der putten (PhD) Analysis

J. Kuipers Sources

G. Nelemans LISA

LISA

Periodic sources analysis – GRID– H.J. Bulten (VU), S. van der Putten (PhD)

Coalescing binaries – BNS, BBH– JvdB, Nikhef staff, pd1 (3 yr), PhD1, PhD2

Advanced Virgo upgrade– T. Bauer (Nikhef), T. Ketel (VU), JvdB, M. Beker (PhD), all PhD and pd

Early Universe – theory and analysis– J.W. van Holten (Nikhef), M. Postma (Nikhef), G. Koekoek (PhD), PhD3, pd1 (3 yr)

Source populations ET and LISA – J. Kuipers (RU), G. Nelemans (RU), D. Rabeling (VU), pd2 (5 yr), PhD4

Multi-messenger analysis (Lofar, optical, UC binaries)– G. Nelemans (RU), H.J. Bulten, PhD5

Running budget– Annual contribution to Virgo

Investment budget: 500 k€ (Nikhef NWO MG 1.5 M€)– Advanced Virgo: Cryo links, seismic isolation, optical systems

6 year program6 PhDs, 2 postdocs

Requested resources – projects

Ambitious program

– Combines resources from universities and research institute

Strong position at international forefront

– Program provides focus, collaboration and coherence

– Timing: Advanced Virgo and LIGO decided now

Attractive context for advanced research

– Excellent environment for postdocs, students, guests

– High quality training

Broadening of scientific experience

– Experimental physics, analysis, GRID computing, astronomy, astrophysics, cosmology, theory

Organize national GW community

– Annual Dutch GW meeting through Nikhef

Links to other programs

– Multi-messenger astroparticle physics (with KM3Net)

Added value of FOM program

Backup slides

LISA

Theoretical Astroparticle physics

LISA

LIGO The largest single enterprise undertaken by NSF. Total capital investment about $ 300 million. Exploitatie about M$ 30/jaar. Enhanced LIGO (2008) is approved, financed and installed. Advanced LIGO (2012) is approved, financed (for M$ 210). LIGO Science Collaboration (LSC) consists of >600 physicists and astronomers; > 45 institutes. Quality of participants is excellent (MIT, Caltech, Stanford, etc.). Three interferometers (ITF): 2 with 4 km arms, 1 with 2 km arms. All ITFs achieved design sensitivity.

Virgo Investment about MEuro 100 by France and Italy. Exploitation about MEuro 10/yr Virgo+ (2008) is approved and financed. Advanced Virgo (2012) approval in 2009. 1 ITF with 3 km arms. ITF sensitivity at design value for f > 700 Hz.

LISA Lisa Pathfinder cost about MEuro 240. Lancering is scheduled for 2010. LISA 3 satellites costs about Euro 1.5 miljard. Highest scientific priority of the 11 Beyond Einstein missions. Decadel review ongoing in USA.

GW fact sheet

Einstein Telescope CDS approved in FP7 for 3M€ Highest scientific priority of 51 proposals JvdB leads WG1 on site selection Appears on ASPERA roadmap as 1 of

Magnificent Seven GW physics

APS Topical group (>1000 members) Future APS division? NL part of EGO consortium?

NRC

De Volkskrant

Technisch weekbladKijk

Intermediair

Teleac Radio5

Civiele Techniek

Outreach – 2008

GW Program Management

Management Structure

– Clear structure established to realize Mass and Focus

– Initial MT composition: GN, JWvH and JvdB (chair)

MT tasks

– Monitor progress in various scientific activities

– Allocation of resources (re-discuss annually)

– Provide steering

– New scientific developments

– Note: 1 PhD not allocated

– Monitor finances

– Outreach

Work towards a national GW community

– Nikhef has a role here (annual and quarterly meetings)

Links to other programs

– Multi-messenger astroparticle physics (e.g. with KM3Net)