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Black Holes: The Inside Story. Presented by: Robert E. Strong strongro@westliberty.edu Elizabeth (Libby) A. Strong strongli@westliberty.edu Richard J. Pollack astronomy@smartcenter.org From: West Liberty State College SMART-Center & Near Earth Object Foundation.
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Black Holes:The Inside Story Presented by: Robert E. Strongstrongro@westliberty.edu Elizabeth (Libby) A. Strong strongli@westliberty.edu Richard J. Pollackastronomy@smartcenter.org From: West Liberty State College SMART-Center & Near Earth Object Foundation National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes:The Inside Story Presented by: Robert E. Strongstrongro@westliberty.edu Elizabeth (Libby) A. Strong strongli@westliberty.edu Richard J. Pollackastronomy@smartcenter.org In an effort to be environmentally friendly: Complete copies of this presentation can be found at www.smartcenter.org/ National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: The History of Gravity Ideas • Galileo Galilei (1564-1642) • Great experimentalist • Proves that all bodies fall at the same rate when taking into account air resistance • ACTIVITY - geometry counts in falling National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: The History of Gravity Ideas • Isaac Newton (1643-1727) • 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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: The History of Gravity Ideas • Force of Gravity is a “Law of Universal Gravitation” • 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
Black Holes - the Inside Story: The History of Gravity Ideas • John Michell (1724-1793) • 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” No Picture Found National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: The History of Gravity Ideas • Henry Cavendish (1731-1810) • Finishes the work of Michell (did the set-up experiment) and Newton, and determines “G” the Gravitational Constant in 1797 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: The History of Gravity Ideas • Albert Einstein (1879-1955) • 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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: The History of Gravity Ideas National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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” National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: The History of Gravity Ideas • Schwarzchild Radius • Escape Velocity = • Set (Celeritas) • Solve for the radius National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: The History of Gravity Ideas • ACTIVITY - Schwarzchild Radius for an Earth mass • G = 6.6742x10-11 m3/kg/s2 • me = 5.9742x1024kg • c = 2.9979x108 m/s • c2 = 8.9874x1016 m2/s2 • rs = 8.8731x10-3m National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: The History of Gravity Ideas • Schwarzchild Radius • What happens when we multiply the mass of a matter object, i.e. clay, 2 times? • ACTIVITY - look at the above equation • Note: = 2 small matter objects of rm = 1 2 x Radius = 1.2599 rm Volume = 2 x Density = 1 x National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: The History of Gravity Ideas • Schwarzchild Radius • What happens when we multiply mass of a Black Hole 2 times? • ACTIVITY - look at the above equation • Note: = 2 small Black Holes of rs = 1 2 x Radius = 2 rs Volume = 8 x Density = 0.25 x National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: The History of Gravity Ideas • Schwarzchild Radius • What happens when we multiply the mass of a matter object, i.e. clay, 10 times? • ACTIVITY - look at the above equation • Note: 10 small matter objects of rm = 1 10 x Radius = 2.1544 rm Volume = 10 x Density = 1 x National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: The History of Gravity Ideas • Schwarzchild Radius • What happens when we multiply mass of a Black Hole 10 times? • ACTIVITY - look at the above equation • Note: 10 small Black Holes of rs = 1 10 x Radius = 10 rs Volume = 1,000 x Density = 0.01 x National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: The History of Gravity Ideas • ACTIVITY - Reflections: • Same Matter objects addition rules: • Radius = • Volume = • Density = • Same Black Holes addition rules: • Radius = rs x mass multiplier • Volume = • Density = National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: The History of Gravity Ideas • Subrahmanyan Chandrasekhar (1910-1995) • Pioneered work on stellar evolution end states • Supernovae • White Dwarfs • Neutron Stars • Black Holes National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: Popular Ideas: Wormholes National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: Popular Culture Black Holes and Wormholes National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: Wormholes in fiction National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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” National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: Black Holes, Wormholes, White Holes, & Quasars National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: Black Holes, Wormholes, White Holes, & Quasars National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: Black Holes, Wormholes, White Holes, & Quasars and Scale National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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! National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: Hawking Radiation • Stephen Hawking 1970 predicted micro-Black Holes may exist and could evaporate via to Hawking Radiation National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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 gamma-ray burst • None found to date National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
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” National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: Discovers Pulsars / Neutron Stars • Crab Nebula with Pulsar / Neutron Star rotating at 30 / seconds National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: Pulsar Lighthouse National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: Neutron Stars - almost there… • Pulsar Jets - Radiation National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: Cygnus X-1, a Binary Stellar Black Hole? National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008
Black Holes - the Inside Story: Cygnus X-1 diagram 20-35 Solar Masses National Science Teachers Association Conference Westin Boston Waterfront, Boston, MA, March 29, 2008