Cosmology. Wormholes for Dummies Question..... First let me say, I am not a scientist, I'm an MBA type, but I am fascinated with physics and the Universe and have the utmost respect for those of you who actually understand it. I was recently watching the Science channel and there was a show on the universe and specifically on wormholes and possible time travel, etc. While I totally get the possibility of traveling into the future via climbing on a spaceship and going at the speed of light for a few light years and then returning back to earth (yeah, I know all about the physical limitations, ultra doses of radiation, etc. but just work with me) and having time have passed much faster than while you were on the ship. What I don't get is some of the theory they discussed on time travel using a wormhole.
I understand the theory of having two openings in space connected by the "tunnel" but here's where I get confused. Hopefully, this is not too elementary for someone to answer. I appreciate the time and help! Wormholes | The Quantum Pontiff. A wormhole is a topological feature of spacetime which essentially links two locales in the universe. Perhaps the most famous (and one of the first examples) considered by physicists is the so-called “Einstein-Rosen bridge.” This is a solution to the vacuum Einstein equations in which one pastes two Schwarzschild solutions together in such a way that there is a link between one part of the universe and another part of the universe. Here is a nice picture: Most people, when they think about wormholes, think about science fiction stories where wormholes are used for traveling between distant locales. Go in one throat of the wormhole and come out on the other side of the universe.
Sounds like fun! Wormhole solutions in general relativity are, however, pretty nasty. Today I was reading Einstein and Rosen’s original paper [Phys. Here we see Einstein and Rosen proposing that quantum theory is a consequence of general relativity! Wormhole. Time Travel Research Center © 2005 Cetin BAL - GSM:+90 05366063183 - Turkey / Denizli Wormhole In physics, a wormhole is a hypothetical topological feature of spacetime that is essentially a "shortcut" through space and time. A wormhole has at least two mouths which are connected to a single throat. If the wormhole is traversible, matter can 'travel' from one mouth to the other by passing through the throat.
The name "wormhole" comes from the following analogy used to explain the phenomenon: imagine that the universe is the skin of an apple, and a worm is traveling over its surface. D efinition Giving a precise definition of a wormhole is slightly tricky. If a Lorentzian spacetime contains a compact region Ω, and if the topology of Ω is of the form Ω ~ R x Σ, where Σ is a three-manifold of nontrivial topology, whose boundary has topology of the form dΣ ~ S², and if furthermore the hypersurfaces Σ are all spacelike, then the region Ω contains a quasipermanent intra-universe wormhole.
General relativity - Wormholes & Time Machines - for *experts* in GR/maths. EDIT: Further clarification in the context of answers/comments received to 20 Jan has been appended EDIT: 21 Jan - Response to the Lubos Expansion appended [in progress, not yet complete] EDIT: 23 Jan - Visser's calculations appended EDIT: 26 Jan - Peter Shor's thought experiments rebutted Summary to Date (26 Jan) The question is: are the Morris, Thorne, Yurtsever (MTY) and Visser mechanisms for converting a wormhole into a time machine valid? Given that the detailed treatment of the Visser case is reproduced below, a valid argument in favour of a wormhole time machine must show how an interval ds^2=0 (the condition for a Closed Timelike Curve) obtains in the absence of a temporal discontinuity.
In considering the MTY (1988) paper, careful consideration should be given to whether the authors actually transport a wormhole mouth or just the coordinate frame that is convenient for describing a wormhole mouth if one happened to exist there. The original postings in chronological order are below. Science/Nature | Wormhole 'no use' for time travel. For budding time travellers, the future (or should that be the past?) Is starting to look bleak. Hypothetical tunnels called wormholes once looked like the best bet for constructing a real time machine. These cosmic shortcuts, which link one point in the Universe to another, are favoured by science fiction writers as a means both of explaining time travel and of circumventing the limitations imposed by the speed of light.
The concept of wormholes will be familiar to anyone who has watched the TV programmes Farscape, Stargate SG1 and Star Trek: Deep Space Nine. The opening sequence of the BBC's new Doctor Who series shows the Tardis hurtling through a "vortex" that suspiciously resembles a wormhole - although the Doctor's preferred method of travel is not explained in detail. But the idea of building these so-called traversable wormholes is looking increasingly shaky, according to two new scientific analyses. Remote connection Law breaker "We aren't saying you can't build a wormhole. Most distant black hole 'heard' munching star - space - 02 August 2012.
The wobbles in energy produced as a black hole consumes a star have been detected from further away than ever before. Because they are so regular, their discoverer likes to think of the wobbles as a kind of sound. "We are able to metaphorically hear a star being devoured by a supermassive black hole," says Rubens Reis of the University of Michigan in Ann Arbor, "4.8mHz would be a very low D-sharp, slightly out of tune. " The wobbles, previously only detected in much closer black holes, allow the black hole feeding process to be compared across vast distances, which in turn acts as a test of Einstein's general relativity, the leading theory of gravity, on cosmic scales.
As the black hole is supermassive, the detection also confirms that black holes feed on star stuff in the same way, whether the black hole is the mass of 10 suns or 10 million suns. "For me that is a rather beautiful thing," says Reis. Star shredder Supermassive black hole Swift J1644+57 was spotted on 28 March last year. Space-time ripples record black hole crashes - space - 19 August 2012. DID monster black holes pull the first galaxies together, or were they born inside those galaxies? It's a long-standing mystery. Now a new analysis of the gravitational ripples from colliding black holes could reveal the answer by helping astronomers reconstruct a crash rather than just surveying its aftermath.
Most large galaxies we see have supermassive black holes at their centres. When these galaxies collide, their black holes merge into one even more massive beast, according to theory. Observations of the final black hole yield no information about the original black holes, however. So astronomers have been trying to look for gravitational waves. Now computer simulations led by Ioannis Kamaretsos of the University of Cardiff, UK, show that the ringdown can also tell us the masses and spins of the two original black holes (arxiv.org/abs/1207.0399). Although nobody has detected gravitational waves as yet, next-generation observatories may spot them within a few years. More from the web. Black Holes, Wormholes and White Hole Videos. What is a Black Hole? According to the general theory of relativity, a black hole is a region of space from which nothing, including light, can escape.
It is the result of the denting of spacetime caused by a very compact mass. Around a black hole there is an undetectable surface which marks the point of no return, called an event horizon. It is called "black" because it absorbs all the light that hits it, reflecting nothing, just like a perfect black body in thermodynamics. What is a Wormhole? In physics, a wormhole is a hypothetical topological feature of spacetime that would be, fundamentally, a "shortcut" through spacetime. What are White Holes? A white hole, in general relativity, is a hypothetical region of spacetime which cannot be entered from the outside, but from which matter and light may escape. Black Holes/CetinBAL-GSM:+90 05366063183-Turkey/Denizli. Time Travel Research Center © 2005 Cetin BAL - GSM:+90 05366063183 -Turkey/Denizli Black Holes, Singularities & Wormholes Contents Black Holes Singularities Wormholes 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. Features of a Black Hole A black hole forms when an object collapses to a small size (perhaps to a singularity) and the escape velocity in its neighborhood is so great that light cannot escape.
Strange Stuff Explained: Black Holes The star passes through its event horizon and disappears from our universe, forming a singularity of infinite density. Stephen Hawking's Universe: Strange Stuff Explained. Invisibility research led to discovery of wormholes. Three years ago, mathematicians in the United States and Great Britain announced the discovery of an invisibility cloak. Yes, you read that right, they calculated the properties for a material that guides light rays around an object so there appears to be nothing there. Now UW mathematics professor Gunther Uhlmann, part of that original research, has taken it a step further — he has discovered an electromagnetic “wormhole,” a tunnel that would make light waves seem to disappear in one place and reappear somewhere else. We’re still waiting to see invisibility capes for sale at the local Toys ‘R Us. But the past three years have seen the birth of a new field in invisibility. Uhlmann has been closely involved since before day one.
The prospect of invisibility prompted Uhlmann and colleagues to revisit their original equations, with some intriguing results. “The idea is to create a tunnel of invisibility, a secret connection between two different points in space,” Uhlmann said.