into the dark: the far future of our universe fred c. adams university of michigan fred c. adams...
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INTO The DARK:INTO The DARK:the FAR FUTUREthe FAR FUTUREof OUR universe of OUR universe
INTO The DARK:INTO The DARK:the FAR FUTUREthe FAR FUTUREof OUR universe of OUR universe
Fred C. Adams
University of MichiganFred C. Adams
University of Michigan
The Copernican Time PrincipleThe Copernican Time Principle
The current cosmological The current cosmological epoch epoch has no special has no special significance.significance.
Interesting physics processes will Interesting physics processes will continue to take place in the future,continue to take place in the future,despite decreasingly energy levelsdespite decreasingly energy levels
Yet Another Principle:Yet Another Principle:
The cosmological future The cosmological future informsinformsour understanding of our understanding of astrophysics astrophysics in the present day universe. in the present day universe.
Cosmological DecadeCosmological Decade
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t =10η years
Cosmic TimelineCosmic Timeline
Five Ages of the UniverseFive Ages of the UniverseFive Ages of the UniverseFive Ages of the Universe
Primordial Era n < 6 Stelliferous Era n = 6 - 14 Degenerate Era n = 14 - 40 Black Hole Era n = 40 - 100 Dark Era n > 100
Primordial Era n < 6 Stelliferous Era n = 6 - 14 Degenerate Era n = 14 - 40 Black Hole Era n = 40 - 100 Dark Era n > 100
The Inflationary Universe
Time in seconds
(Guth)
Matter > Antimatter Matter > Antimatter
Dark matter abundance freezes before universe is 1 second old
The synthesis of light elements beginsThe synthesis of light elements begins when the universe is one second oldwhen the universe is one second old
and ends three minutes later…and ends three minutes later…
Helium
Deuterium
Lithium
(Schramm)
The Primordial EraThe Primordial EraThe Primordial EraThe Primordial Era
The Big Bang Inflation Matter > Antimatter Quarks --- protons & neutrons Nuclear synthesis of the light elements Cosmic Microwave Background Universe continues to expand
The Big Bang Inflation Matter > Antimatter Quarks --- protons & neutrons Nuclear synthesis of the light elements Cosmic Microwave Background Universe continues to expand
WMAP: Cosmic Background Radiation
WMAP: Cosmic Background Radiation
The VIRGO consortium
Large Scale Structure of the Universe
The Present Epoch
Cosmological ParametersCosmological Parameters
IslandUniverse
14 Gyr
54 Gyr
92 Gyr
Dark matter halos approacha well-defined asymptotic formwith unambiguous total mass, outer radius, density profile
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ρ ≈ρ0
ξ (1+ ξ )3
Andromeda: Our sister galaxyAndromeda: Our sister galaxy
Collision with AndromedaCollision with Andromeda
AB
C
Earth swallowed by the SunEarth swallowed by the Sun
(probably…)
Red Dwarf saves the EarthRed Dwarf saves the Earth
sun
red dwarf
earth
moon
Red dwarf captures the Earth
Sun exits with one red dwarf as a binary companion
Earth exits with the other red dwarf
Sun and Earth encounter binary pair of red dwarfs
9000 year interaction
Solar System ScatteringSolar System Scattering
Many Parameters +Chaotic Behavior
Many Simulations Monte Carlo Scheme
Cross Sections vs Stellar MassCross Sections vs Stellar MassCross Sections vs Stellar MassCross Sections vs Stellar Mass
2.0 M1.0 M
0.5 M0.25 M
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σej
=C0
aPAU
⎛
⎝ ⎜
⎞
⎠ ⎟M∗
Msun
⎛
⎝ ⎜
⎞
⎠ ⎟
−1/ 2
where
C0 =1350 ±160 (AU)2
Galilean Satellites:
Ganymede Callisto Io Europa
Icy worlds are easy to make
Some current data suggest that life on Earth might have originated deep underground,independent ofsunlight, so that life could arise onfrozen planets across the Galaxy.
Galaxy continues to make new stars.Time scales are lengthened by: - Recycling- Infall onto disk- Reduced SF rate
Star formation continues until the galaxy runs out of gas (at n = 14)
Long term Evolution of Red Dwarfs
Long term Evolution of Red Dwarfs
Log
[L]
Temperature
Life Span of Red DwarfsLife Span of Red Dwarfs
Lif
etim
e (T
rill
ion
yr)
Mass (Msun)
Late time light curve for Milky Way
(Adams, Graves, & Laughlin 2004)
The Stelliferous EraThe Stelliferous EraThe Stelliferous EraThe Stelliferous Era Stars dominate energy production Lowest mass stars increasingly important Star formation and stellar evolution end
near cosmological decade n = 14 Future tells us why stars become red giants,Future tells us why stars become red giants, why dark matter halos have their forms, how why dark matter halos have their forms, how
to define the mass of a galaxy, new results to define the mass of a galaxy, new results on orbit instabilities, dynamical scattering…on orbit instabilities, dynamical scattering…
Stars dominate energy production Lowest mass stars increasingly important Star formation and stellar evolution end
near cosmological decade n = 14 Future tells us why stars become red giants,Future tells us why stars become red giants, why dark matter halos have their forms, how why dark matter halos have their forms, how
to define the mass of a galaxy, new results to define the mass of a galaxy, new results on orbit instabilities, dynamical scattering…on orbit instabilities, dynamical scattering…
Nuclear physics Nuclear physics determinesdetermineshow stellar evolution how stellar evolution takestakesplace, and sets the place, and sets the cosmic cosmic abundance of the abundance of the elements, elements, as well as the as well as the inventory of inventory of the Degenerate the Degenerate Era… Era…
Inventory of Degenerate EraInventory of Degenerate Era Brown dwarfs (from brown dwarfs) White dwarfs (from most stars, M=0.08-8) Neutron stars (from massive stars M > 8) Stellar Black Holes (from largest stars)
Brown dwarfs (from brown dwarfs) White dwarfs (from most stars, M=0.08-8) Neutron stars (from massive stars M > 8) Stellar Black Holes (from largest stars)
BD WD
Brown Dwarf CollisionsBrown Dwarf Collisions
J. Barnes
White Dwarfs of Degenerate Era Accrete Dark Matter Particles
White Dwarfs of Degenerate Era Accrete Dark Matter Particles
Power = quadrillions of watts
Dynamical Relaxation of the GalaxyDynamical Relaxation of the Galaxy
Stellar scattering changes the structure of the galaxy over time
Spiral disk becomes extended and diffuse
Most stars are lost, but a few fall to center
Stellar scattering changes the structure of the galaxy over time
Spiral disk becomes extended and diffuse
Most stars are lost, but a few fall to center
Time scale = 20 cosmological decadesTime scale = 20 cosmological decades
Proton DecayProton Decay Many possible channels Lifetime is recklessly uncertain Experiments show that n > 33 Theory implies that n < 45
Changes the universe more dramatically than any other process in our future history
Many possible channels Lifetime is recklessly uncertain Experiments show that n > 33 Theory implies that n < 45
Changes the universe more dramatically than any other process in our future history
Proton decay channelProton decay channel
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d
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e⊕
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π 0
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u
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XP
Fate of Degenerate Objects
Temperature Temperature
P
ower
P
ower
The Degenerate EraThe Degenerate EraThe Degenerate EraThe Degenerate Era
Inventory includes Brown Dwarfs, White Dwarfs, Neutron Stars, and Black Holes Star formation through brown dwarf collisions White dwarfs capture dark matter particles Galaxy relaxes dynamically Black holes accrete stars, gas, and grow
Era ends when Protons decay at cosmological decade n = 40
Inventory includes Brown Dwarfs, White Dwarfs, Neutron Stars, and Black Holes Star formation through brown dwarf collisions White dwarfs capture dark matter particles Galaxy relaxes dynamically Black holes accrete stars, gas, and grow
Era ends when Protons decay at cosmological decade n = 40
Every galaxy has a
supermassive black hole anchoring its center
Mbh = millions to billions of Suns
Every galaxy produces about one million stellar mass black holes
Hawking Radiation
BlackBlack holehole
Virtual particles
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λ ≈GM ≈ Rs
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TH =1/(8πGM)
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τ =1065 yr M /Mo[ ]3
The Black Hole EraThe Black Hole EraThe Black Hole EraThe Black Hole Era
Black holes are brightest stellar objects Generation of energy via Hawking radiation Every galaxy contributes one supermassive
and about one million stellar black holes Black hole lifetime is mass dependent:
Black holes are brightest stellar objects Generation of energy via Hawking radiation Every galaxy contributes one supermassive
and about one million stellar black holes Black hole lifetime is mass dependent:
One solar mass: n=65Million solar mass: n=83Galactic mass: n=98Horizon mass: n=131
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tT ∝Mbh3
The Dark EraThe Dark EraThe Dark EraThe Dark Era
No stellar objects of any kind Inventory of elementary particles:
electrons, positrons, neutrinos, & photons Positronium formation and decay Low level annihilation
No stellar objects of any kind Inventory of elementary particles:
electrons, positrons, neutrinos, & photons Positronium formation and decay Low level annihilation
The Cosmos could experience a Future Phase Transition
As the phase transition completes, the laws of physics could change, and the universe gets a new start
As our own universeAs our own universeexperiences its time-experiences its time-line, other parts of line, other parts of the global space-timethe global space-time(other universes) can (other universes) can live through their ownlive through their ownlifetimes, as part of lifetimes, as part of a cosmic archipelagoa cosmic archipelagosometimes called thesometimes called theMULTIVERSE.MULTIVERSE.
SummarySummarySummarySummary Our current understanding of the laws of
physics and astrophysics allow us to construct a working picture of the future.
Studying physical processes of the future provides insight into current astrophysical problems, e.g., the reason for red giants, structure of dark matter halos, dynamical scattering problems, defining the masses of galaxies, etc.
Our current understanding of the laws of physics and astrophysics allow us to construct a working picture of the future.
Studying physical processes of the future provides insight into current astrophysical problems, e.g., the reason for red giants, structure of dark matter halos, dynamical scattering problems, defining the masses of galaxies, etc.
DisclaimerDisclaimerDisclaimerDisclaimer
As one journeys deeper into future time, projections necessarily become more uncertain (this talk stops at n = 100).
As we learn more about the fundamental laws of physics, or if the laws change with cosmological time, corrections (both large and small) to this timeline must be made.
As one journeys deeper into future time, projections necessarily become more uncertain (this talk stops at n = 100).
As we learn more about the fundamental laws of physics, or if the laws change with cosmological time, corrections (both large and small) to this timeline must be made.
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