81. Time Travel Is It Possible Interview with Steven Gibbs, documented incident of possible timeslippage, scientific premises of possibility, warping time, cosmic strings, paradoxes, wormholes, black holes, movie and book reviews. http://www.strangemag.com/timetravel.html

STRANGEhome TIME TRAVEL Is Time Travel Possible? Has it been accomplished? Who are those who claim to have travelled through time? What do scientists think about time travel? Inspired by the Time Travel theme of Strange Magazine 14 (Fall, 1994) our Strange Web Site Time Travel pages include some of the high points of that issue, as well as some classic time-bending High Strangeness from our Louisiana correspondent Ken Meaux. Ken's haunting piece has been reprinted, retold, and cited many times since it debuted in Strange Magazine 2 (Spring, 1989). Never-before-published material includes Douglas Chapman's quick tour of some time travel movies. Sherrill Roberts discusses the possibility that modern physics may provide some mechanisms for moving though time. Time Travel book reviews and a suggested reading list round out the Time Travel Pages. HIGH STRANGENESS: TIME TRAVELLER Ken Meaux's unforgettable telling of a documented incident of possible time-slippage. QUANTUM STRANGENESS AND SPACETIME Sherrill Roberts discusses the scientific premises that suggest that time travel may be possible, including proposed mechanisms for warping time. Enter the world of worm holes, black holes, cosmic strings, and time travel paradoxes in this referenced article. TIME TRAVEL MOVIES Douglas Chapman touches on some significant time travel films.

82. Black Holes black holes. Click here to go to the JPU200Y home page. Click here to go to the Physics Virtual Bookshelf. Another Approach to black holes. http://www.upscale.utoronto.ca/GeneralInterest/Harrison/BlackHoles/BlackHoles.ht

Black Holes Click here to go to the JPU200Y home page. Click here to go to the Physics Virtual Bookshelf Click here to go to the UPSCALE home page. Introduction: "A luminous star, of the same density as the Earth, and whose diameter should be two hundred and fifty times larger than that of the Sun, would not, in consequence of its attraction, allow any of its rays to arrive at us; it is therefore possible that the largest luminous bodies in the universe may, through this cause, be invisible." Pierre Laplace, The System of the World , Book 5, Chapter VI (1798). Evolution of Stars Clouds of Hydrogen begin condensing into more dense clusters due to gravitation. Eventually the density gets high enough that the Hydrogen begins fusing into Helium. This fusion releases energy, mostly in the form of electromagnetic radiation. Our sun is currently in this phase. Note that the gravitational attraction of the matter of the star is trying to make it smaller; this is balanced by the radiation pressure that is trying to push the matter outward making the star bigger. In class we showed a photograph of a birthplace of stars; the URL is http://www.seds.org/hst/M16WF2.html

83. Imagine The Universe Science The science section of Imagine the Universe! from NASA. Explore a universe of black holes, dark matter, and quasars http://imagine.gsfc.nasa.gov/docs/science/science.html

Imagine Home Explore a universe of black holes, dark matter, and quasars... A universe full of extremely high energies, high densities, high pressures, and extremely intense magnetic fields which allow us to test our understanding of the laws of physics. For more advanced articles, try the Advanced Science page The Basics Start your exploration of the high energy universe here. This section includes explanations of some of the concepts and principles used to study and understand the universe. The Electromagnetic Spectrum Multiwavelength Astronomy X-ray Astronomy Lightcurves, Spectra, and Images ... Gamma-Ray Astronomy Cosmic Objects The universe is more than just stars, dust, and empty space. Explore some of the objects that make up our universe, from our own sun to distant pulsars and black holes. Stars Black Holes The Sun White Dwarfs ... Cosmic Rays Cosmic Questions Scientific discoveries often reveal new mysteries. Take a look at a few of the mysteries that astronomers and astrophysicists are working on right now. Origin and Destiny of the Universe Growth of Massive Black Holes Nature of Dark Matter Dark Energy ... The Solar Corona The Search for Answers A look at the tools and methods scientists use to study the high energy universe.

84. Beyond The Event Horizon, BlackHols black holes With Angular Momentum. The Schwarzchild black hole, while fascinating, will probably never be found in nature. Do black holes Really Exist? http://www.astronomical.org/astbook/blkhole.html

Beyond the Event Horizon Robert W. Lindsay December 01, 1993 You may freely copy and/or distribute this material provided that it is not altered or distributed for profit Beyond the Event Horizon: An Introduction to Black Holes Imagine a world in which a beam of light rose into the sky only to fall back to the ground at your feet. Or, picture an infinite continuum of parallel universes, each inhabited by slightly different parallel twins of yourself.Visualize a place in which all the laws of physics, that combine to make our universe the place that it is, vanish into inscrutable infinities. Welcome to the world of one nature's most bizarre phenomena: the black hole. Figure 1: The Rubber Sheet Analogy of Gravity Shortly after the publication of the General Theory, physicists began to explore this strange new world. The theory is so very complex, and the mathematics so difficult, that even today, scientists have barely scratched the surface of this powerful theory. One of the very earliest solutions to the equations was developed by the German physicist, Karl Schwartzschild, in 1916. The Schwartzschild Black Hole Figure 2: Diagram of Schwarzchild Black Hole Assuming that we could find a volunteer to journey into a Schwarzchild black hole, what would he experience? Passing through the photon-sphere, he would be flooded with intense light. As our volunteer left the brightness, he would find himself in utter darkness. He would feel his velocity increase to unbelievable levels. Approaching the event horizon, our astronaut would be subjected to tidal forces of astronomical proportions. His feet would seem to weight uncounted trillions of tons more than his head. In a blinding instant, our poor volunteer would be disintegrated into atoms. He would then crash into the singularity, where his mortal remains would be summarily smashed out of existence (4).

85. CNN.com - Space - Australian Telescope Searching Southern Skies For Black Holes CNN http://www.cnn.com/2000/TECH/space/05/09/australia.telescope/index.html

space Editions myCNN Video ... Feedback CNN Sites CNN CNN Europe CNNfn CNNSI myCNN CNNfyi AllPolitics Languages Search CNN.com CNNSI.com CNNfn.com The Web SPACE TOP STORIES Mir cargo vessel abandoned John Zarrella: Lessons learned from Challenger Last rendezvous for Mir Beginning of the end for Mir ... MORE TOP STORIES Bush signs order opening 'faith-based' charity office for business Rescues continue 4 days after devastating India earthquake DaimlerChrysler employees join rapidly swelling ranks of laid-off U.S. workers Disney's GO.com is a goner ... MORE MARKETS 4:30pm ET, 4/16 DJIA NAS SPORTS Jordan says farewell for the third time ... LOCAL EDITIONS: CNN.com Europe change default edition MULTIMEDIA: video video archive audio multimedia showcase ... more services E-MAIL: Subscribe to one of our news e-mail lists Enter your address: DISCUSSION: chat feedback CNN WEB SITES: CNNfyi.com CNN.com Europe AsiaNow Spanish ... Korean Headlines TIME INC. SITES: Go To ... Time.com People Money Fortune EW CNN NETWORKS: CNN anchors transcripts Turner distribution SITE INFO: help contents search ad info ... jobs WEB SERVICES: Australian telescope searching southern skies for black holes Cangaroo II telescope against backdrop of star-trails and the Large Magellanic Cloud.

86. Conservation Environment Ecosystems: Rouge Park Toronto escape. It is formed by the death of a massive star and only the most massive stars become black holes at the end of their lives. Even http://www.blackhole.on.ca/

Welcome to THE BLACK H O LE OF CONSERVATION BLACK HOLE : A cosmic body of extremely intense gravity from which nothing, not even light can escape. It is formed by the death of a massive star and only the most massive stars become black holes at the end of their lives. Even though a black hole is difficult to observe on account of both its small size and the fact it emits no light; it can still be seen however, by the effects of its enormous gravitational fields on nearby matter. CONSERVATION - ENVIRONMENT - ECOSYSTEMS "If present trends and mechanisms continue without alteration, then things like species extinction are a certainty within 20 years." Gord Miller, Environmental Commissioner of Ontario The Globe and Mail, November 2, 2000 "We, as humans, have initiated one of the greatest episodes of mass extinction the world has ever seen. Given current estimates of extinction rates, by the year 2020 only 30-70% of all living species on earth will survive." Royal Ontario Museum, Toronto

87. Black Hole -- From Eric Weisstein's World Of Physics Uncharged, zero angular momentum black holes are called Schwarzschild black holes. Uncharged nonzero angular momentum black holes are called Kerr black holes. http://scienceworld.wolfram.com/physics/BlackHole.html

Astrophysics Black Holes Black Hole A massive astrophysical object that is theorized to be created from the collapse of a neutron star . The gravitational forces are so strong in a black hole that they overcome neutron degeneracy pressure and, roughly speaking, collapse to a point (known as a singularity). Even light cannot escape the gravitational pull of a black hole within the black hole's so-called Schwarzschild radius Uncharged, zero angular momentum black holes are called Schwarzschild black holes . Uncharged nonzero angular momentum black holes are called Kerr black holes . Nonspinning charged black holes are called . Charged, spinning black holes are called Kerr-Newman black holes . The black hole no hair theorem shows that mass charge , and angular momentum are the only properties which a black hole can possess. type of black hole mass angular momentum charge Kerr black hole M J Q Kerr-Newman black hole M J M J Schwarzschild black hole M J Q In 1965, R. Penrose proved the singularity theorem , which says that a singularity must reside inside every imploding star, and therefore every black hole. In 1969, Lifschitz, Khalatnikov, and Belinsky showed that tidal gravity oscillates chaotically near the singularity. They also found the particular type of singularity, now known as a BKL singularity . Black holes can pulsate, as was recognized by Press (1971). Over the next decade or so, the pulsations were shown to always be stable using perturbation methods. In 1973, S. Hawking showed that black holes radiate as if they have a

88. Cambridge Relativity Nontechnical descriptions of cosmology, black holes, cosmic strings, inflation, quantum cosmology, and string theory. http://www.damtp.cam.ac.uk/user/gr/public/

National Cosmology Supercomputer - New! Cosmology Black holes National Cosmology Supercomputer - New! Cosmology Black holes ... [Next]

89. CNN.com - Black Hole Seen Ripping Star Apart - Feb. 18, 2004 black holes will eat just about anything, and now astronomers have confirmed that stars are on their menus. Skip to main content, SPACE.com About black holes. http://www.cnn.com/2004/TECH/space/02/18/shc.blackhole.star/

International Edition MEMBER SERVICES The Web CNN.com Home Page World U.S. Weather ... Special Reports SERVICES Video E-mail Services CNNtoGO Contact Us SEARCH Web CNN.com Black hole seen ripping star apart By Robert Roy Britt SPACE.com Because of the momentum and energy of the process, only part the disrupted star's mass (indicated by the white stream in this illustration) was swallowed by the black hole, while the rest of the star was flung away into the surrounding galaxy. Story Tools RELATED Interactive: Anatomy of a black hole SPACE.com: About black holes New twists on the Milky Way's big black hole The true shape of black holes Survival tips for black hole travelers ... Chandra observatory YOUR E-MAIL ALERTS Black hole Chandra X-ray Center Space Exploration National Aeronautics and Space Administration (NASA) or Create your own Manage alerts What is this? SPACE.com Black holes will eat just about anything, and now astronomers have confirmed that stars are on their menus. Observations from three space-based X-ray telescopes over about a decade provide the first solid evidence of a star being torn apart and partly swallowed by a black hole. Astronomers already have plenty of evidence for black holes consuming gas that swirls inward and is superheated, generating radiation in many wavelengths from radio to visible light and X-rays. They have long assumed that whole stars could be torn apart by the gravitational tug of a black hole, but proof has been elusive.

90. Www.KidsAstronomy.com-Black Hole black holes. What are black holes? Have you ever had to vacuum your bed room? When you do things towards it. How do black holes form? http://www.kidsastronomy.com/black_hole.htm

The Universe Solar System Black Holes Galaxies ... Stars Q uasars What are black holes? Have you ever had to vacuum your bed room? When you do, watch closely because you will see the dirt, and crumbs start to move towards the vacuum cleaner. A black hole is similar to a vacuum cleaner, cleaning up debries left behind in outer space. It is not suction power that makes things fall into a black hole. Suction would not be strong enough. Instead a black hole uses the power of gravity to pull things towards it. How do black holes form? When a large star runs out of fuel it can no longer support its heavy weight. The pressure from the star's massive layers of hydrogen press down forcing the star to get smaller and smaller and smaller. Eventually the star will get even smaller than an atom. Imagine that for a moment an entire star squashed up into less space than a tiny atom. How can something get smaller, but retain the same amount of mass, or stuff? It is really quite simple. If you take a sponge the size of a soda can you can easily squish it in your hands until it is completely covered. But here is the interesting part. If you make something smaller by squishing it, it's gravity becomes much stronger. Imagine then, if you squish a star into the size of an atom how powerful it's gravity would become.

91. Black Holes: The Ultimate Abyss--Astronomy/Space Lesson Plan (grades 6-8)--Disco Students learn that even though black holes all have characteristics in common, they come in three different sizes. , Reference materials on black holes. http://school.discovery.com/lessonplans/programs/blackholes/

Grades K-5 Grades 6-8 Grades 9-12 Astronomy/Space ... Health History Ancient History U.S. History World History Life Science Animals Ecology Human Body The Microscopic World ... Weather For our newsletter and special teacher promotions. 6-8 > Astronomy/Space Grade level: 6-8 Subject: Astronomy/Space Duration: Two class periods Objectives Materials Procedures Adaptations ... Credit Find a video description, video clip, and discussion questions. Black Holes: The Ultimate Abyss Use our free online Teaching Tools to create custom worksheets, puzzles and quizzes on this topic! Students will understand the following: Even though black holes all have characteristics in common, they come in three different sizes. Each size black hole has characteristics different from the others. Only research materials are required for this activity. You might want to have a selection of sources on hand in the classroom, but students should go to the library or the Internet for additional research. Reference materials on black holes A computer with Internet access Review with your students what they have learned about black holes.

92. Time Travel Einstein, Lorentz factor, black holes, angular momentum, rotational vortex theory, chronoton particles, dilation, parallel universes and paradoxes. http://www.geocities.com/Area51/Zone/5199/timetravel.html

Breaking Time's Arrow Time is a part of everything we do, but not easy to comprehend. Nearly everybody has seen a time travel movie or two in his or her life. Almost all of the science-fiction movies are at least a little time-travel based. The last two science-fiction movies that I saw, Sphere and Lost in Space , both had time travel involved with it. We are familiar with three-dimensional space travel. Moving up, down, left, right, forward and backward are easy for us to do or to visualize. Time on the other hand is different. Movement in time is limited to forward. It is asymmetrical and one dimensional. This is called time's arrow. It also is applied to memories. We can't remember what we "did" tomorrow. Cause always precedes effect. (Einre) I propose that time travel is possible. Time travel has many different theories, problems, and paradoxes. There are many theories on time travel. Most of the theories at least partially use Einstein's work. Einstein's theory of relativity states that at speeds close to the speed of light, color, size, time, shape, mass and other variables change slightly. The constant c represents the speed of light (approximately three hundred million meters per second or one hundred eighty six thousand miles per second). (Lawrence 34-35) The Lorentz factor Sqrt(1-(v/c) )is multiplied or divided to all formulas where any of the above variables are concerned, i.e.,d

93. WSU | Ask Dr. Universe | The BIG Questions Dear Dr. Universe, What is a black hole? Carolyn Muncie, Indiana But so many of you have been asking about black holes, I thought I d slip this in. http://www.wsu.edu/DrUniverse/black.html

Washington State University Home Dear Dr. Universe, What is a black hole? Carolyn Muncie, Indiana I KNOW I said I'd write more about sleep. But so many of you have been asking about black holes, I thought I'd slip this in. Then back to sleep. So here we go: A black hole is an object whose escape velocity is greater than the speed of light. At least that's how astronomer Jeff Brown puts it. Escape velocity is how fast one body has to go to escape from the gravity of another body. To escape from the Earth, you'd have to go a bit more than 25,000 miles an hour. To escape from a black hole, you'd have to go faster than the speed of light, which is about 186,000 miles a SECOND! That's about 669,600,000 miles an hour. Naturally, this presents a problem. The speed of light is the fastest anything can move, and only light can move that fast. Things made out of matter, like humans and spacecraft, can't get even close to that speed. One of you asked what the inside of a black hole looks like.

94. CNN.com - Space - New X-ray Telescope Could Peer Inside Black Holes - September CNN http://www.cnn.com/2000/TECH/space/09/14/blackholetelescope.ap/index.html

space Editions myCNN Video ... Feedback CNN Sites CNN CNN Europe CNNfn CNNSI myCNN CNNfyi AllPolitics Languages Search CNN.com CNNSI.com CNNfn.com The Web SPACE TOP STORIES Mir cargo vessel abandoned John Zarrella: Lessons learned from Challenger Last rendezvous for Mir Beginning of the end for Mir ... MORE TOP STORIES Bush signs order opening 'faith-based' charity office for business Rescues continue 4 days after devastating India earthquake DaimlerChrysler employees join rapidly swelling ranks of laid-off U.S. workers Disney's GO.com is a goner ... MORE MARKETS 4:30pm ET, 4/16 DJIA NAS SPORTS Jordan says farewell for the third time ... LOCAL EDITIONS: CNN.com Europe change default edition MULTIMEDIA: video video archive audio multimedia showcase ... more services E-MAIL: Subscribe to one of our news e-mail lists Enter your address: DISCUSSION: chat feedback CNN WEB SITES: CNNfyi.com CNN.com Europe AsiaNow Spanish ... Korean Headlines TIME INC. SITES: Go To ... Time.com People Money Fortune EW CNN NETWORKS: CNN anchors transcripts Turner distribution SITE INFO: help contents search ad info ... jobs WEB SERVICES: New X-ray telescope could peer inside black holes Hubble Space Telescope image of an accretion disk formed by a black hole in galaxy NGC 7052 (AP) Astronomers have developed a design for an X-ray telescope so staggeringly powerful that it could see black holes gulping matter in distant galaxies.

95. Blackhole Final.wpd Jan. 31 2000 version; to appear in Vand. J. Ent. L. Pract. Of black holes and Decentralized LawMaking. in Cyberspace. David G. Post (1). http://www.temple.edu/lawschool/dpost/blackhole.html

Of Black Holes and Decentralized Law-Making in Cyberspace David G. Post There is, within the (rapidly-growing) community of people who spend their time thinking about law and policy in cyberspace, a rather interesting debate taking place. Though it is not always characterized in these terms, it reflects a conflict between competing visions of "order" and "disorder" in social systems. This is by no means a "new" debate, but it takes on a new shape in the rather special conditions of cyberspace or so, at least, I hope to suggest in what follows. The Incident . Last January, Professor Tom Field of the Franklin Pierce Law Center (FPLC), posted the following message to the Cyberprof listserve: "To all: Assuming that this message isn't screened out by the [the server at the University of Texas that hosts the Cyberprof discussion group], you might be interested in a 'small' problem FPLC faces. A few weeks ago, someone 'bounced' some spam off our server. It somehow corrupted our email system, and [now] I am beginning to get messages like this: The message that you sent was undeliverable to the following: ipww@ljx.com

96. 87 FAQs About Black Holes From Ask The Astronomer - The Astronomy 87 FAQs about black holes at the Astronomy Cafe. Additional Online Resources (ca April 2000) Basic black hole Primer Jillian s Guide to black holes. http://www.astronomycafe.net/qadir/abholes.html

97. Redirect Learn about Einstein's Theory of Relativity online. The class covers cosmology, the Twin Paradox, space travel, and black holes. http://members.aol.com/drlorentz/index.html

This page has moved to http://www.drphysics.com please update your bookmarks.

98. Growing Black Holes 2004 GROWING black holes Accretion in a Cosmological Context. The preliminary program is now available for the conference `Growing Black http://www.mpa-garching.mpg.de/~bh-grow/

99. Black Hole Black Hole. It is now believed that ray and Gammaray observatories. To learn more about black holes, see also black holes and Beyond. http://heasarc.gsfc.nasa.gov/docs/blackhole.html

Help/FAQ What's New Site Map NASA Homepage ... HEASARC Quick Links -Quick Links- -Archive Interfaces- Argus: proposal info Astrobrowse: worldwide catalog search Browse: search HEASARC archives NVO Data Inventory Service SkyMorph: search variable objects SkyView: virtual observatory CalDB: Calibration database Coord Converter Date Converter Energy Converter FITS: standard data format FITSIO: FITS subroutine library FTOOLS: general s/w for FITS files fV: FITS file editor Hera: remote data analysis service nH: Column Density RPS proposal submission RXTE ASM weather map Time Converter TIPTOPbase: atomic data Viewing: possible obs times WebPIMMS: flux/cnt converter WebSpec: spectral sims X-ray Background Tool Xanadu: data analysis suite X-ray, Gamma-ray, EUV Source Finder xTime: RXTE time converter -Resources- Bibliography Contact Info History of High-Energy Astronomy Meetings Staff Tour the site What's New APOD: Astronomy Picture of the Day Ask an Astronomer HEASARC Picture of the Week Images, Spectra, Light curves Imagine the Universe! StarChild (K-8 EPO) WebStars: gen. astronomy info/news

100. Chandra :: Field Guide To X-ray Astronomy :: X-Ray Sources Stars, supernovae, black holes, white dwarfs, galaxies. http://chandra.harvard.edu/xray_sources/

X-Ray Sources Solar System - The Sun's hot outer atmosphere produces X-rays, but because it is so close (a mere 93 million miles!), it is too bright for Chandra's sensitive eyes. Chandra can observe other objects in our solar system such as comets and Jupiter. Stars - The hot outer atmospheres, or coronas, of normal stars such as our sun produce X-rays. X-ray observations are useful for understanding how the flaring activity of stars can change as stars evolve, and how the evolution of stars is changed if they are in a close binary system. White Dwarf Stars - White dwarf stars are dense, burnt-out remnants of stars like the sun. They are formed when the star contracts after using up its nuclear fuel. When matter from a nearby star falls onto a white dwarf star, X-rays are produced. - When a star blows apart in a supernova, the explosion creates a remnant of multi-million degree gas that shines brightly in X-rays for thousands of years. X-ray observations can reveal the dynamics of the explosion and heavy elements present in the remnant.

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