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Black Holes in Universe From Stellar Masses to Supramassive Objects in Galaxies Max Camenzind Black Holes in Universe From Stellar Masses to Supramassive Objects in Galaxies Max Camenzind Center for Astronomy Heidelberg (ZAH) @ Landessternwarte (2005)

Prologue: Chandrasekhar 1983 • „The black holes of nature are the most perfect macroscopic Prologue: Chandrasekhar 1983 • „The black holes of nature are the most perfect macroscopic objects there are in the universe: the only elements in their construction are our concepts of space and time. And since the general theory of relativity provides only a single unique family of solutions for their descriptions, they are the simplest objects as well. “ • No matter is involved in their construction [i. e. no EOS], a Black Hole is a global vacuum solution with horizon, a kind of gravitational soliton. in Chandrasekhar (1983): „The Mathematical Theory of BHs“

Topics • The Long History of Black Hole Physics. • The Year 1963 and Topics • The Long History of Black Hole Physics. • The Year 1963 and Kerr Black Hole Gravitational field is not Newtonian ! • Evidence for the Existence of Black Holes 4 Classes of Astrophysical Objects. „No Hair Plane (Glatzenebene)“ (M, a). • Accretion: New Paradigm of disk accretion onto Black Holes (Balbus & Hawley 1991). • Magnetic Fields - The Spin Paradigm: The Ergosphere as a Source of Energy Launch Jets (Blandford & Znajek 1977) still largely not understood. • Beyond Einstein ? Dreams and Future

The Long Way towards BHs • 1915: Einstein postulates the field equations (together with The Long Way towards BHs • 1915: Einstein postulates the field equations (together with Hilbert). • 1916: Schwarzschild Solution Schwarzschild radius RS = 2 GM/c² = 3 km M / MS • Einstein denied the reality of Black Holes … He considered Black Holes as a mere mathematical curiosity. • This view changed after his death detection of Quasars (> 1963) observation of Cygnus X-1 (1971)

1963 – Foundation of Black Holes 1923 - Milestone 1: George Birkhoff: Schwarzschild spacetime 1963 – Foundation of Black Holes 1923 - Milestone 1: George Birkhoff: Schwarzschild spacetime geometry is the unique spherically symmetric solution of the Einstein vacuum field equations • 1939 - Robert Oppenheimer & Hartland Snyder show gravitational collapse of a pressureless homogeneous fluid sphere formation of a trapped region • 1963 – Milestone 2: Roy Kerr solves the Einstein vacuum field equations for uncharged symmetric rotating systems • 1963 – Milestone 3: Quasars are detected fuelled by accretion onto Black Holes • 1965 - Ezra Newman and collaborators solve the Einstein -Maxwell equations for charged rotating systems • 1967 - Werner Israel presents proof of a "no hair" theorem

1968 – 1977: Golden Age • 1968 – Brandon Carter uses Hamilton-Jacobi theory to 1968 – 1977: Golden Age • 1968 – Brandon Carter uses Hamilton-Jacobi theory to derive 1 st-order equations of motion for particle moving in Kerr black holes Kerr Ray-Tracing • 1969 - Roger Penrose discusses the Penrose process for the extraction of the spin energy from a Kerr black hole Free energy of BHs • 1971 – Milestone 4: Identification of Cygnus X-1/HDE 226868 as a binary black hole candidate system. • 1973 - David Robinson completes the proof of the uniqueness theorem for Kerr black holes • 1977 – Milestone 5: Blandford-Znajek Process electromagnetic spin energy extraction from rotating black holes

4 Laws of Black Hole Mechanics • 1972 - Stephen Hawking proves that the 4 Laws of Black Hole Mechanics • 1972 - Stephen Hawking proves that the area of a classical black hole's event horizon cannot decrease. • 1972 - Jacob Bekenstein suggests that black holes have an entropy proportional to their surface area due to information loss effects • 1973 - James Bardeen, Brandon Carter, and Stephen Hawking propose 4 laws of black hole mechanics in analogy with laws of thermodynamics Free energy • 1973 - Stephen Hawking applies quantum field theory to black hole spacetimes and shows that black holes will radiate particles with a black-body spectrum which can cause black hole evaporation concept is important, but astrophysically not relevant, and still debated.

1978 – 2005: Observations • 1978 – Sargent et al. show evidence for a 1978 – 2005: Observations • 1978 – Sargent et al. show evidence for a supermassive BH in the center of Messier 87 (“serious possibility”). This has been very much debated but confirmed ! • 1992 – Microquasar GRS 1915+105 found. • 1997 – Fe line redshifts of the innermost portions of accretion disks around rotating supermassive black holes • 2000 - Evidence for the hypothesis that Sagittarius A* is a supermassive black hole at the centre of the Milky Way galaxy • 2002 – The most distant Black Hole found: Cosmological Redshift z = 6. 43 ! (< 1 Gyear old) • 2005 – BHs confirmed in ~ 20 X-Ray Binary Systems ! • 2005 – BHs confirmed in ~ 30 nearby galactic centers ! • 2005 – BHs found in ~ 100, 000 Quasars !

The Year 1963 and the Physics of Kerr Black Hole The Year 1963 and the Physics of Kerr Black Hole

How to Treat Gravity of BHs ? In GR the spacetime is a differentiable How to Treat Gravity of BHs ? In GR the spacetime is a differentiable manifold. The most natural thing is to to foliate it in t=const spatial hypersurfaces St. 1 Measures the “clocks ticking rates” on two St Measures the “stretching” of coordinates St 4 6 Measures distances among points on a St unit timelike 4 -vector normal to St

Spacetime is stationary and axisymmetric 2 Parameters: (i) Mass M (ii) Ang. Mom. a Spacetime is stationary and axisymmetric 2 Parameters: (i) Mass M (ii) Ang. Mom. a „Charge not relevant in Astrophysics“ Event Horizon r. H = M + (M² - a²)1/2

Source: Mass Source: Ang. Mom. Also for NSs ! Source: Mass Source: Ang. Mom. Also for NSs !

Gravity Probe-B will confirm the Existence of Gravitomagnetism Gravity Probe-B will confirm the Existence of Gravitomagnetism

4 Laws of BH Mechanics Bekenstein 1973, Bardeen et al. 1973, Hawking 1974, 1975 4 Laws of BH Mechanics Bekenstein 1973, Bardeen et al. 1973, Hawking 1974, 1975

Extracted by magnetic effects Extracted by magnetic effects

Blandford-Znajek Process Load at infinity J Blandford & Znajek (1977) „Split-Monopole“ magnetosphere coupled to Blandford-Znajek Process Load at infinity J Blandford & Znajek (1977) „Split-Monopole“ magnetosphere coupled to rotating Horizon with Znajek Horizon bc drives closed current system Subject of strong criticism (Punsley)

A Modern Version of BZ Mechanism OLC: Outer Light Surface, compact for Black Holes A Modern Version of BZ Mechanism OLC: Outer Light Surface, compact for Black Holes A: Alfven Surface Plasma injection from near ms orbit; Plasma accretion causal: slow ms, Alfven and fast ms points Proto-Jet wwwww Current Sheet Magnetic fields advected from „Infinity“

Twisting of Magnetic Fields • Except for induction terms, evolution of toroidal magnetic field Twisting of Magnetic Fields • Except for induction terms, evolution of toroidal magnetic field ~ Newtonian MHD • Source: Differential plasma rotation • Schwarzschild: no shear ! • Extreme Kerr: biggest effect ! T ~ RBf Operates outside horizon

Black Holes 2 Energy Reservoirs • Potential energy tapped by accretion X-rays • Rotational Black Holes 2 Energy Reservoirs • Potential energy tapped by accretion X-rays • Rotational energy tapped by magnetic fields, similar to rotating neutron stars (Blandford & Znajek 1977) will feed energy of JETS ! LRot = ERot/tbrake ~ 1046 erg/s (MH/109 MS) (t. H/tbrake) LRot = ERot/tbrake ~ 1038 erg/s (MH/10 MS) (t. H/tbrake) tbrake = f (a, B, …) [BZ 1977] LBZ = k BH² r. H²c (a/M)² (WF[WH-WF]/WH²) ~ MH

Anatomy of Black Holes Anatomy of Black Holes

Black Hole Ergosphere Extended Boundary Layer For a > 0. 7, radii move inside Black Hole Ergosphere Extended Boundary Layer For a > 0. 7, radii move inside ergosphere

Each form of matter will be driven to corotation within the ergosphere ! Boundary Each form of matter will be driven to corotation within the ergosphere ! Boundary Layer near Horizon ~ r. H WH = w(r. H) In Schwarzschild: No rotation near Horizon !

a = 0. 5 a = 1. 0 a = 0. 5 a = 1. 0

Outflows in Quasars & Micro. Quasars ? „Stochastic Funnel. Flow“ Krolik 2005 Conical Outflow Outflows in Quasars & Micro. Quasars ? „Stochastic Funnel. Flow“ Krolik 2005 Conical Outflow Disk Inflow

Field Line Twisting by Rotating Black Holes a=0 a = 0. 5 a = Field Line Twisting by Rotating Black Holes a=0 a = 0. 5 a = 0. 9 a =. 998 GRMHD Simulations (Hawley et al. 2005)

Astrophysical Black Holes in the Universe Astrophysical Black Holes in the Universe

Black Holes as Astrophysical Objects • [ Primordial Black Holes: M < 2 MS] Black Holes as Astrophysical Objects • [ Primordial Black Holes: M < 2 MS] • Stellar Black Holes: 2. 2 MS < M < 100 MS • Intermediate Mass Black Holes 100 MS < M < 105 MS (? ) • Supermassive Black Holes: 105 MS < M < 1010 MS reside in center of galaxies at all redshifts, 0 < z < 10 (? ).

1971 monitored by UHURU High-Mass XB Cygnus X-1 Black Holes are formed in stellar 1971 monitored by UHURU High-Mass XB Cygnus X-1 Black Holes are formed in stellar Collapse >100. 000 BHs in the Galaxy

Cyg X-1 – Activity Cycles (VLA / RXTE) Radio X-Rays HX When high in Cyg X-1 – Activity Cycles (VLA / RXTE) Radio X-Rays HX When high in X-rays minimum in radio and vice versa Jet launch

Low-Mass X-Ray Binaries Low-Mass X-Ray Binaries

DIFFERENT BINARY SYSTEMS • type of the donor star type of accretion (wind or DIFFERENT BINARY SYSTEMS • type of the donor star type of accretion (wind or Roche lobe overflow) • very different scales: Every X-ray binary is a possible microquasar! J. A. Orosz

Stellar Mass Spectrum Clear Separation NSs vs BHs NS Stellar Mass Spectrum Clear Separation NSs vs BHs NS

X-Ray Emission: VARIABILITY on all Time Scales GX 339 -4 lightcurve • Variations = X-Ray Emission: VARIABILITY on all Time Scales GX 339 -4 lightcurve • Variations = changes in the state of the source • lightcurves: GX 339 -4 / GRS 1915+105 Variations on very different time scales ! “easy” observations for human time scale 1996 2003 GRS 1915+105 X (2 -10 ke. V) Radio (2, 25 GHz) Rau et al (2003)

accretion / ejection coupling Mirabel et al (1998) Marscher et al (2002) • cycles accretion / ejection coupling Mirabel et al (1998) Marscher et al (2002) • cycles of 30 minutes in GRS 1915+105 : ejections after an X-ray dip refilling of the internal part of the disc ? transient ejections during changes of states same phenomenum in the quasar 3 C 120 ? far slower !

GRS 1915+105 Microquasar GRS 1915+105 Microquasar

SUPERLUMINAL EJECTIONS same Lorentz factor as in Quasars : ~ 5 -10 VLBI at SUPERLUMINAL EJECTIONS same Lorentz factor as in Quasars : ~ 5 -10 VLBI at 22 GHz ~ 1. 3 cm VLA at 3. 5 cm ~ arcsec. scale ~ milliarcsec. scale • • ~103 Mirabel & Rodriguez (1994) Move on the sky plane times faster Jets are two-sided (allow to solve equations max. distance)

QUASARS MICROQUASARS Quasar 3 C 223 VLA at 1477 MHz ~ 20 cm Microquasar QUASARS MICROQUASARS Quasar 3 C 223 VLA at 1477 MHz ~ 20 cm Microquasar 1 E 1740. 7 -2942 radio (VLA) observations at 6 cm Mirabel et al. 1992

Non-thermal Radio Plasma ----- 100 kpc ------ Black Holes in E-Galaxies Drive Jets Cygnus Non-thermal Radio Plasma ----- 100 kpc ------ Black Holes in E-Galaxies Drive Jets Cygnus A (VLA) 3 C 219 (VLA)

A. Müller (LSW) 2004 A. Müller (LSW) 2004

Black Hole Mass ~ Bulge Mass for Inactive Galaxies 30 Nearby Galaxies: MH ~ Black Hole Mass ~ Bulge Mass for Inactive Galaxies 30 Nearby Galaxies: MH ~ 0. 14% MB Magorrian Relation (N. Häring & H. -W. Rix: Ap. JL 2004)

Mass vs Luminosity of Quasars LE = 2 x 1031 Watt x (M/MS) ~ Mass vs Luminosity of Quasars LE = 2 x 1031 Watt x (M/MS) ~ 5 x 104 LS maximum luminosity minimum mass for BHs

Black Hole „Two-Hair Plane“ BH s in Galactic Centers and QSOs Neutron Stars Microquasars, Black Hole „Two-Hair Plane“ BH s in Galactic Centers and QSOs Neutron Stars Microquasars, Stellar BHs, M* > 30 Intermediate Mass BHs ? ? ? Population III BHs at High Redshifts RL Quasars, Radio Galaxies

Spin a of a Black Hole can be determined from Photon Propagation Equations of Spin a of a Black Hole can be determined from Photon Propagation Equations of geodesics integrable Carter Integrals

Image of a Ring Image of a Ring

Line Emission from BH Accretion Line Emission from BH Accretion

Schwarzschild Extreme Kerr Extreme Redshift Schwarzschild Extreme Kerr Extreme Redshift

High. Redshift Quasars (SDSS) Form in Primordial Clusters Very massive BHs form very early High. Redshift Quasars (SDSS) Form in Primordial Clusters Very massive BHs form very early !

Cosmic Quasar Population H 0 = 70 km/s/Mpc Wk = 0. 0 Wm = Cosmic Quasar Population H 0 = 70 km/s/Mpc Wk = 0. 0 Wm = 0. 3 WL = 0. 7 QSO densities augmented by factor 3 due to obscuration M. Camenzind 2005

Cosmic History & Black Holes recombination Cosmic Dark Age: no light no star, no Cosmic History & Black Holes recombination Cosmic Dark Age: no light no star, no quasar; IGM: HI First light: the first galaxies and quasars in the universe Epoch of reionization: radiation from the first object lit up and ionize IGM : HI HII reionization completed, the universe is transpartent and the dark ages ended today

Credit: G. Fishman et al. , BATSE, CGRO, NASA BATSE GRB Final Sky Map: Credit: G. Fishman et al. , BATSE, CGRO, NASA BATSE GRB Final Sky Map: Astronomy Picture of the Day 2000 June 28

Gamma-Ray Burst Durations Two Populations: Short – 0. 03 -3 s Long – 3 Gamma-Ray Burst Durations Two Populations: Short – 0. 03 -3 s Long – 3 -1000 s Possible third Population 1 -10 s

A Slow Explosion of massive star Formation of rotating BH with JETS long duration A Slow Explosion of massive star Formation of rotating BH with JETS long duration burst Credit: Y. Grosdidier (U. Montreal) et al. , WFPC 2, HST, NASA “Astronomy Picture of the Day: 2003 March 25”

Merging of 2 neutron stars short bursts formation of a BH On the Origin Merging of 2 neutron stars short bursts formation of a BH On the Origin of Gold: Astronomy Picture of the Day: 2005 May 15

New Insight: Accretion is Turbulent - not Viscous New Paradigm for ADs: Disks are New Insight: Accretion is Turbulent - not Viscous New Paradigm for ADs: Disks are not viscous – Disks are turbulent Turbulence driven by weak magnetic fields Radiative MHD key vehicle [Balbus & Hawley 1991, 98]

New Paradigm: BHs in Different Accretion States • BHs grow by accretion processes. • New Paradigm: BHs in Different Accretion States • BHs grow by accretion processes. • MHD turbulence drives angular momentum transport in acretion disks (Balbus & Hawley magnetorotational instability, MRI). Disks are turbulent, not viscous ! • The well-known thin disk accretion model (Shakura & Sunyaev) only applies for high accretion rates, typically more than a few percent Eddington. • Truncated accretion at lower rates.

 Two different accretion states depending on the accretion rate for given mass Two different accretion states depending on the accretion rate for given mass

Brinkmann & Camenzind LSW 2004 Brinkmann & Camenzind LSW 2004

Esin et al. 1995 A. Müller (LSW 2004) Esin et al. 1995 A. Müller (LSW 2004)

Accretion States of Cyg X-1 High State (HS) [truncation radius near rms] Low State Accretion States of Cyg X-1 High State (HS) [truncation radius near rms] Low State (LS) [truncation radius moves away] Transitions Energy emitted in Comptonized photons

What tell us X-rays? MCG-6 -30 -15 HST/WFPC-2 XMM-Newton 0. 5 -10 ke. V What tell us X-rays? MCG-6 -30 -15 HST/WFPC-2 XMM-Newton 0. 5 -10 ke. V light curve (Fabian et al. 2002) Rapid X-ray variability of AGN strongly suggests X-rays come from innermost regions of accretion disk

GRMHD Accretion from a Torus as Initial Condition Non-Radiative Accretion Flows De Villiers, Hawley GRMHD Accretion from a Torus as Initial Condition Non-Radiative Accretion Flows De Villiers, Hawley & Krolik 2003 - 2005 (3 D non-conservative GRMHD in BL); Gammie et al. 2003, 2004 (2 D conservative GRMHD in BL coordinates) Initial condition (exact mech. equilibrium + weak magnetic fields)

Meridional Plane through a BH Funnel Outflows Colour: Density Torus + weak magnetic fields Meridional Plane through a BH Funnel Outflows Colour: Density Torus + weak magnetic fields Initial State Turbulent Thick Disk Keplerian „Final State“ Gammie et al. 2004

Magnetic Fields (originally confined to torus) evolve towards a completely turbulent state. Angular momentum Magnetic Fields (originally confined to torus) evolve towards a completely turbulent state. Angular momentum is transported outwards, some accreted to spin up BH.

Fender 2004; Belloni 2005 Fender 2004; Belloni 2005

When Plasma is included Ergospheric Jets ? When Plasma is included Ergospheric Jets ?

Beyond Einstein – The Observer‘s Dreams Planck XEUS XMM Today 2012 2020 2030 NASA Beyond Einstein – The Observer‘s Dreams Planck XEUS XMM Today 2012 2020 2030 NASA Homepage

XEUS - ESA XEUS - ESA

Beyond Einstein – Heavy Numerical Computations Robust parallel GRMHD Codes Beyond Einstein – Heavy Numerical Computations Robust parallel GRMHD Codes

Beyond Einstein: Is there really a Singularity in the Black Hole ? Vacuum energy Beyond Einstein: Is there really a Singularity in the Black Hole ? Vacuum energy is present everywhere in the Universe ( Dark Energy) Change the Interior of a Black Hole Regular state ! Mazur & Mottola 2001, 2004

Conclusions - Visions • Mass spectrum is continuous from stellar to 10 billion solar Conclusions - Visions • Mass spectrum is continuous from stellar to 10 billion solar masses. Gap from 100 – 105 MS ? • But Kerr parameter a is not yet measurable ! • GRMHD (> 2000) Plasma dynamics near BHs can be successfully treated within Godunov schemes Use Kerr coordinates, bc within horizon ! MRI accretion theory is now tractable ! • Strong B-field limit (which is unphysical !): GR Magnetodynamics confirms BZ mechanism of energy extraction out of the ergosphere Jets are ergospheric plasma flows ? • Weak field limit of GRMHD (relevant for MRI) is in unsatisfactory state, most results based on non -conservative methods Turbulent accretion to rotating BHs essentially unsolved, but now tractable with modern methods. • Also include radiation effects, which is important for high accretion rates at high z.