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Black Holes:
The Inside Story
Presented by:
Robert E. Strong
[email protected]
Elizabeth (Libby) A. Strong
[email protected]
Richard J. Pollack
[email protected]
From: West Liberty State College SMART-Center &
Near Earth Object Foundation
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
1
Black Holes:
The Inside Story
Presented by:
Robert E. Strong
[email protected]
Elizabeth (Libby) A. Strong [email protected]
Richard J. Pollack
[email protected]
In an effort to be environmentally friendly:
Complete copies of this presentation can be found at
www.smartcenter.org/
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
2
Black Holes - the Inside Story:
The History of Gravity Ideas
• Aristotle (384-322 BC)
• Great thinker - lousy
experimentalist
• Qualitative, not
Quantitative
• But, that did not stop
us from using his ideas
for nearly 1,800 years
as unquestioned facts
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Aristotle (continued)
• Everything has a
tendency to fall from
up to down, toward the
Earth
• Heavy objects fall
faster than do light
objects
• ACTIVITY - Falling
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Galileo Galilei (15641642)
• Great experimentalist
• Proves that all bodies
fall at the same rate
when taking into
account air resistance
• ACTIVITY - geometry
counts in falling
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National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Isaac Newton (16431727)
• Stood on Galileo’s
shoulders and took his
ideas further and deeper
• Gravity as a force at a
distance
• Force of gravity varies as
the inverse square of the
distance between centers
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National Science Teachers Association Conference
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Force of Gravity is a
“Law of Universal
Gravitation”
•
5/22/2017
 
m1m2
Fg  2
r
Where:
– Fg = force of gravity
– m1 and m2 are masses
– r = distance between
the centers of mass
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
No Picture Found
5/22/2017
• John Michell (17241793)
• Brilliant scientist, in
1784 pointed out that a
star that was sufficiently
massive and compact
would have such a strong
gravitational force that
light would not be able to
escape the surface,
making a “Dark Star”
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
• John Michell, using
Newton’s ideas of
gravity as a force, saw
that if a strong enough
gravity were at the
surface, that not only
could material objects
not leave the surface,
but light itself may
bend and be trapped
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Henry Cavendish (17311810)
• Finishes the work of Michell
(did the set-up experiment)
and Newton, and determines
“G” the Gravitational
Constant in 1797
5/22/2017
Gm1m2
Fg 
2
r
National Science Teachers Association Conference
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Simon Pierre LaPlace
(1749-1827)
• Independently
suggested the Michell
idea of a “Dark Star”
in his early writings
and works
• Later editions left the
“Dark Star” idea out
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National Science Teachers Association Conference
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Albert Einstein (18791955)
• In 1916 offers the Theory
of General Relativity
• Suggests that gravity is
not a force, but rather is a
curvature in space and
time
• Gravity is geometry
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National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Karl Schwarzchild
(1873-1916)
• In 1916 used Einstein’s
General Relativity to
define a Black Hole
• Defined the “event
horizon” gravitational
radius of a black hole
AKA the …
“Schwarzchild Radius”
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National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Schwarzchild Radius
• Escape Velocity =
2Gm
Ve 
r
• Set Ve  c (Celeritas)
• Solve for the radius


5/22/2017
2Gm
rs  2
c
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Black Holes - the Inside Story:
The History of Gravity Ideas
• ACTIVITY - Schwarzchild
Radius for an Earth mass
2Gme
rs  2
c
• G = 6.6742x10-11 m3/kg/s2
• me = 5.9742x1024kg
• 
c = 2.9979x108 m/s
• c2 = 8.9874x1016 m2/s2
• rs = 8.8731x10-3m
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National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
• ACTIVITY - How big
is this?
• If rs = 8.8731x10-3m
• A US dime has a radius
of 8.955x10-3m
• Or about 1% greater
than the Schwarzchild
Radius for the mass of
the Earth compressed
into a Black Hole
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
• If the Earth has a
Schwarzchild Radius
rs = 8.8731x10-3m
• This is 7.1863x108
times smaller in radius
• With a density of
3.7112x1026 times
greater
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Schwarzchild Radius
=
2 small matter
objects of rm = 1
2 x Radius =
1.2599 rm
Volume = 2 x
Density = 1 x
5/22/2017
2Gm
rs  2
c
• What happens when
we multiply the mass
of a matter object, i.e.
clay, 2 times?
 • ACTIVITY - look at
the above equation
3
r

unit
number
• Note: m
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Schwarzchild Radius
2Gm
rs  2
c
=
2 small Black
Holes of rs = 1
2 x Radius =
2 rs
Volume = 8 x
Density = 0.25 x
5/22/2017
• What happens when
we multiply mass of a
Black Hole 2 times?
 • ACTIVITY - look at
the above equation
• Note: rs  m
National Science Teachers Association Conference
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Schwarzchild Radius
10 small matter
objects of rm = 1
10 x Radius =
2.1544 rm
Volume = 10 x
Density = 1 x
5/22/2017
2Gm
rs  2
c
• What happens when
we multiply the mass
of a matter object, i.e.
clay, 10 times?
 • ACTIVITY - look at
the above equation
3
r

unit
number
• Note: m
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
21
Black Holes - the Inside Story:
The History of Gravity Ideas
• Schwarzchild Radius
2Gm
rs  2
c
10 small Black
Holes of rs = 1
10 x Radius =
10 rs
Volume = 1,000 x
Density = 0.01 x
5/22/2017
• What happens when
we multiply mass of a
Black Hole 10 times?
 • ACTIVITY - look at
the above equation
• Note: rs  m
National Science Teachers Association Conference
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Black Holes - the Inside Story:
The History of Gravity Ideas
• ACTIVITY - Reflections:
– Same Matter objects addition rules:
3
• Radius = rm  unit number
• Volume =
4
3
 rm 
3
mass
• Density =
V

– Same
Black Holes addition rules:

• Radius = rs x mass multiplier
3
4
• Volume =  rs x multiplier

3
mass
• Density =
V
5/22/2017
National Science
Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
• ACTIVITY
• Simulation via Paper Clips, Balloons, and
nanoLight Second Strings:
– Same Matter objects addition rules:
• Radius = cluster on nls string = rm x (mass multiplier)1/3
• Volume = rm x (mass multiplier)
• Density = same as rm
– Same Black Holes addition rules:
• Radius = chain length on nls string = rs x mass multiplier
• Volume = discover and discuss
• Density = discover and discuss
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Arthur A. Eddington
(1882-1944)
• In 1919 experimentally
verified General Relativity
by observing star light
curving next to the Sun
during a solar eclipse
• Thought no
Black Holes
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Subrahmanyan
Chandrasekhar (19101995)
• Pioneered work on
stellar evolution end
states
–
–
–
–
5/22/2017
Supernovae
White Dwarfs
Neutron Stars
Black Holes
National Science Teachers Association Conference
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Black Holes - the Inside Story:
Mass is the Defining (final) Word
• Still mostly theory …
numbers will range
• Limit of mass for a
White Dwarf 1.35 to 2.1
solar masses (< 1.44)
• Neutron Star limits 2-3
solar masses
• Any stellar mass > 5
solar masses will
become a Black Hole
5/22/2017
National Science Teachers Association Conference
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Black Holes - the Inside Story:
Mass is easily found in the dance
• The mass of an object
determines if it is a
Main Sequence Star,
White Dwarf, Neutron
Star, or Black Hole
• Best way to determine
the mass of a star is if
it is a part of a binary
system
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
28
Black Holes - the Inside Story:
The History of Gravity Ideas
• John Wheeler (1911-)
• Worked in General
Relativity, gravitational
collapse, and quantum
gravity
• Coined the phrase
“Black Hole” in 1967
5/22/2017
National Science Teachers Association Conference
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Black Holes - the Inside Story:
The History of Gravity Ideas
• Kip Thorn (1940-)
• Student of Wheeler
• Long time friend and
colleague of Stephen
Hawking (on-going bets)
• Expert on General
Relativity, Black Holes,
Relativity, Time Travel,
Wormholes, and White
Holes
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
Popular Ideas: Wormholes
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Black Holes - the Inside Story:
Popular Culture Black Holes and Wormholes
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National Science Teachers Association Conference
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Black Holes - the Inside Story:
Wormholes in fiction
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Black Holes - the Inside Story:
Wormholes
• Wormholes have the
problem of the
pathways becoming
unstable if the Black
Hole is rotating
• Spatiotemporal frame
dragging occurs - this
“pinches” off the
pathway separating the
two ends
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
Black Holes, Wormholes, White Holes, & Quasars
• Problem with using a
Black Hole /
Wormhole (if stable)
for getting around the
universe is the
difficulty of tidal
forces and …
• the horror of under
going “Fractal
Spaghettification”
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
35
Black Holes - the Inside Story:
Black Holes, Wormholes, White Holes, & Quasars
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
Black Holes, Wormholes, White Holes, & Quasars
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
Black Holes, Wormholes, White Holes, & Quasars and Scale
5/22/2017
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Black Holes - the Inside Story:
As Cosmic Bull Dozers
• Active Galactic Nuclei, i.e.,
Quasars, or super massive
Black Holes at the center of a
galaxy may create cavities and
voids of extra-galactic material
and may move the material for
entire clusters of galaxies over
billions of years
• Shaping the galactic fabric of
the Universe on the grandest of
scales tens of millions ly across
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
39
Black Holes - the Inside Story:
Milky Way Monster?
• Does the Milky Way
Galaxy have a super
massive Black Hole at
its center like most
galaxies?
• Watch the latest
evidence - you decide
• Remember a compact
object > 5 solar masses
is a Black Hole!
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
40
Black Holes - the Inside Story:
Milky Way Monster!
• The video shows ten
years of observation
and extrapolation by
Prof. Ghez of stars at
the core of the Milky
Way Galaxy orbiting
about an object of 4
million solar masses!
• Watch SO-2 and
SO-16
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
41
Black Holes - the Inside Story:
The History of Gravity Ideas
• Stephen Hawking (1942-)
• One of the greatest minds
of our time
• Along with Thorne,
Hawking has pushed the
envelope of our
understanding of the
Universe via General
Relativity & Black Holes
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
42
Black Holes - the Inside Story:
Hawking Radiation
• Stephen Hawking 1970
predicted micro-Black
Holes may exist and
could evaporate via to
Hawking Radiation
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
43
Black Holes - the Inside Story:
Hawking Radiation
• Hawking Radiation, if
it exists makes micro
Black Holes “bright”
in radiation of photons
and particles
• Eventually the micro
Black Holes will
evaporate in a gammaray burst
• None found to date
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
44
Black Holes - the Inside Story:
The History of Gravity Ideas
• Jocelyn Bell-Burnell
(1943-)
• 1967 Discovered Pulsars
• And thus … Neutron Stars
• Solved the LGM-1
mystery
• Poster person for “dealing
with the men only - good
‘ol boys science club”
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
45
Black Holes - the Inside Story:
Discovers Pulsars / Neutron Stars
• Crab Nebula with
Pulsar / Neutron Star
rotating at 30 / seconds
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
Pulsar Lighthouse
5/22/2017
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Black Holes - the Inside Story:
Neutron Stars - almost there…
• Pulsar Jets - Radiation
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
Cygnus X-1, a Binary Stellar Black Hole?
5/22/2017
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Black Holes - the Inside Story:
Cygnus X-1 diagram
20-35
Solar
Masses
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
1.0 Solar Mass Black Hole
• ACTIVITY - Schwarzchild
Radius for a Solar Mass
2Gms
rs  2
c
•
•
•
•
•
5/22/2017
G = 6.6742x10-11 m3/kg/s2
ms = 1.9884x1030 kg
8 m/s
c
=
2.9979x10

c2 = 8.9874x1016 m2/s2
rs = 2.9532x103 m ≈ 3 km
National Science Teachers Association Conference
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51
Black Holes - the Inside Story:
1.0 Solar Mass Black Hole Unit
• Thus the Schwarzchild Radius rs for a 1.0 Solar
Mass Black Hole is…
• ≈ 3 km
2Gms
• Looking at the equation rs  c 2
• We see that to estimate the size of a Black
Hole’s Schwarzchild radius or radius of the
event horizon, we only need to use mass units
in solar massesand multiply by 3km
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
52
Black Holes - the Inside Story:
MWG 4 Million Solar Mass BH
• ACTIVITY - Schwarzchild
Radius for 4 million SM
2Gme
rs  2
c

5/22/2017
rs  ms x3km
• m4Msm = 4x106 Solar Masses
x 3 km/Solar Mass

• rs = 1.2x107 km
• ≈ 40 light seconds
National Science Teachers Association Conference
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Black Holes - the Inside Story:
MWG 400 Billion Solar Mass BH
• ACTIVITY - Schwarzchild
Radius for Milky Way Galaxy
2Gme
rs  2
c

5/22/2017
rs  ms x3km
• mmwg = 400x109 Solar
Masses x 3 km/Solar Mass

• rs = 1.2x1012 km
• ≈ 4.003x106 light seconds
• ≈ 0.127 light Years
National Science Teachers Association Conference
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Black Holes - the Inside Story:
Universe 80 Billion Galaxy Mass BH
• ACTIVITY - Schwarzchild
Radius for mass of Universe
2Gms
rs  2
c
• mu = 80x109 MWG x
1.2x1012 km
• rs = 9.6x1022 km

• ≈ 3.202x1017 light seconds
• ≈ 1.015x1010 light Years
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
55
Black Holes - the Inside Story:
Universe “Total Mass” Black Hole
• ACTIVITY - Schwarzchild
Radius for entire mass + dark
matter + Dark Energy of Universe
• Universe thought to be
– 73% Dark Energy
– 23% cold Dark Matter
– 4% Matter (80x109 MWG)
• Mutotal = 80x109 MWG x 1.2x1012
km x (≈ 25)
• rs = 2.4x1024 km
• ≈ 8.0x1018 light seconds
• ≈ 2.5x1011 light Years
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
56
Black Holes - the Inside Story:
Implications of a Universe “Total Mass” BH
• ACTIVITY - Schwarzchild Radius
for entire mass + dark matter +
Dark Energy of Universe
• Universe thought to be
– 73% Dark Energy
– 23% cold Dark Matter
– 4% Matter (80x109 MWG)
• ≈ 2.5x1011 light Years or ≈ 250
Billion light years
• If the “comoving” distance to the
edge of the visible universe is
about 46.5 billion light years ≠age
(the age is 13.73±0.12 Billion years)
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
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Black Holes - the Inside Story:
What is it like in a Black Hole?
• ACTIVITY - Schwarzchild
Radius for entire mass + dark
matter + Dark Energy of Universe
• IF rs for the entire mass of the
universe ≈ 2.5x1011 light Years or
≈ 250 Billion light years
• IF the “comoving” distance to the
edge of the visible universe is
about 46.5 Billion light years…
• THEN we are presently within
the event horizon of a Black Hole
having the mass of the entire
Universe with room to spare
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
58
Black Holes - the Inside Story:
What is it like in a Black Hole2?
• ACTIVITY - Lets try to make
sense of all this …
• IF rs for the entire mass of the
universe ≈ 250 Billion light years
• IF the real radius of the visible
universe ≈ 46.5 billion light years
• THEN we and all we know are
presently / actually within the
event horizon of a Black Hole
• THEN a Universe sized Black
Hole does not have a singularity
at its core, just look around you
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
59
Black Holes - the Inside Story:
The History of Gravity Ideas continues…
• Robert E. Strong
(1958-)
• Modeling wormholes
with soap bubbles
• Trying to keep up with
the fun of it all
• Constantly wondering
about the “cosmic
perspective”
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National Science Teachers Association Conference
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Black Holes - the Inside Story:
Discussions, Questions, & Sharing
Please feel free to contact us
Note: the Power Point is found at www.smartcenter.org/blackhole
Presented by:
Robert E. Strong
[email protected]
Elizabeth (Libby) A. Strong [email protected]
Richard J. Pollack
[email protected]
From: West Liberty State College SMART-Center &
Near Earth Object Foundation
5/22/2017
National Science Teachers Association Conference
Westin Boston Waterfront, Boston, MA, March 29, 2008
61