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I've often thought obviously the Earth spins at a much greater rate at the poles than the, say, equator.

It depends on what you mean by "spin[ning] at a greater rate". If you measure the rate of spin at the pole and rotational equator in radians per 24 hours they are the same. They both turn through 6.28 radians (360 degrees) per day at exactly the same rate per unit of time. The angular velocity is different. At the equator the rate is approximately 1609 kph and at the polar rotational point it is ~zero (the Earth wobbles slightly so it isn't precisely zero).


Is there no benefit to garner from such? If no, why?

Benefit gained? Under special relativity you age at a infinitesimally slower rate at the equator due to the relativistic effects of the speed relative to any other point north or south of the equator. You save a few microseconds over the course of a lifetime if you spend it all on the equator relative to someone who spends their entire life sitting on one of the poles. But general relativity states that on a spinning non-rigid sphere like the Earth the shape will form (mass will be redistributed, i.e. the equatorial bulge) and reach a point of equilibrium such that all clocks, polar, equatorial and in between will register elapsed proper time at the same rate.


In the end - no benefit.


To what point is gravity a dispersion agaisnt being a ruling factor, and as well from what motion - it's creation in this regard?

I don't understand this last question. Gravity dispersion against what ruling factor?



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I suppose what I was saying in response is that it seems to maintain a certain constant but it also disperses (in the sense of away from the Earth), though is the rate of dispersal always the same constant?


If not, then it goes back to the original point of maintaining a constant. ('Kinda like looking at it's cycles in reverse).



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I suppose what I was saying in response is that it seems to maintain a certain constant but it also disperses (in the sense of away from the Earth), though is the rate of dispersal always the same constant?

Ah.. You're asking if the gravitational field varies constantly as the inverse square of the change in radius from the center of gravity.


As far as we know, in the classical approximation it does. When we look out into the universe mass seems to obey Newton's law of gravitation everywhere. We observe gravity here on Earth today and we know how it obeys. When we look far out into the universe we're also looking far back in time. It doesn't seem to have changed over the course of billions of years.



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Re: Not a Stupid Question


Something missed here:


a gravitational anomaly is an example of a gauge anomaly: it is an effect of quantum mechanics–usually a one-loop diagram—that invalidates the general covariance of a theory of general relativity combined with some other fields. The adjective "gravitational" is derived from the symmetry of a gravitational theory, namely from general covariance. It is also known as diffeomorphism anomaly, since general covariance is symmetry under coordinate reparametrization; i.e. diffeomorphism.




General covariance is the basis of general relativity, the current theory of gravitation. Moreover, it is necessary for the consistency of any theory of quantum gravity, since it is required in order to cancel unphysical degrees of freedom with a negative norm, namely gravitons polarized along the time direction. Therefore all gravitational anomalies must cancel out.




The anomaly usually appears as a Feynman diagram with a chiral fermion running in the loop (a polygon) with n external gravitons attached to the loop where n = 1 + D / 2 where D is the spacetime dimension. Anomalies occur only in even spacetime dimensions. However, anomalies can occur in the case of an odd dimensional spacetime manifold with boundary.


:yum: :yum:



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Re: Not a Stupid Question




i was thinking in ...


The Hawking Radiation:




"In this method, the Hawking radiation restores general covariance in an


effective theory of near-horizon physics which otherwise exhibits a gravitational anomaly


at the quantum level. The method has been shown to work for broad classes of black


holes in arbitrary space–time dimensions. These include static black holes, accreting or


evaporating black holes, charged black holes, rotating black holes, and even black rings.


In the cases of charged and rotating black holes, the expected superradiant current is


also reproduced.


Keywords: Black holes; gravitational anomalies; Hawking radiation.




end quoted


from this PDF




, Darby




and Time Machines using portable rotational black holes



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Re: Not a Stupid Question


Welcome to Neverland...


well kinda ;)


Leonhardt and his colleague Paul Piwnicki at the Royal Institute of Technology in Sweden have devised a way to create black holes in the lab. Inside their machines, light will be sucked in, never to return.



On Earth, the nearest things we have to black holes are vortices. Tornadoes, for example, can suck up trees, roofs and trucks. Their power comes from the low pressure in the centre of the vortex. And according to Leonhardt and Piwnicki's calculations, a vortex should apply the same sort of inward force to light.


If the vortex rotates much faster than the light can move, any ray that strays too close to its centre will get caught and dragged inexorably inwards (see Diagram). The light will eventually be absorbed by the gas. So just like a real black hole, the vortex has an event horizon beyond which escape is impossible.



That is a really good way of looking at utilizing vortices...that was back in 2000, since light has been slowed - so did any experiment continue with this?


As well if this is taking light and using black hole theory, if the light were a medium of moving information, then if you could utilize the same fashion with the vortex to model white hole theory would that try and send information back/forward, or is it lost no matter what in that sense?


(what would happen to entanglement or is that the whole idea???)



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Re: Not a Stupid Question


Welcome to LA LA LAnd...




ScienceDaily (Sep. 5, 2009) — Using one of the greatest artificial sources of radiation energy, University of Nevada, Reno researcher and faculty member Roberto Mancini is studying ultra-high temperature and non-equilibrium plasmas to mimic what happens to matter in accretion disks around black holes.


Physics department professor and chair Mancini has received a $690,000 grant from the U.S. Department of Energy to continue his research in high energy density plasma; plasmas are considered to be the fourth state of matter. He will serve as principal investigator for a project titled "Experiments and Modeling of Photo-ionized Plasmas at Z."


"Receiving awards such as this exemplifies the academic caliber and national importance of the work in our Physics Department," Jeff Thompson, dean of the College of Science said. "We're proud of the team of researchers here working on cutting-edge science."


Mancini has been studying the atomic and radiation properties of high-energy density plasmas for more than 15 years, and this new grant will allow him to further explore what happens to matter when it is subjected to extreme conditions of temperature and radiation – similar to what happens to many astrophysical objects in the universe.


The research will enable astrophysicists to better understand what happens around black holes and in active galactic nuclei. Scientists will also better understand the application of high-energy density plasmas to energy production, such as controlled nuclear fusion (produced in the laboratory), and production of X-ray sources for a variety of applications.


"Using theories and tools created here at the University to design and analyze experiments, we then go to the only national facility that has the capacity to deliver the high-intensity flux of X-rays required to perform and measure these experiments," Mancini said. "We custom build instrumentation in our machine shop that meets the high standard set by the national facility so that it will fit onto the target chamber of the pulsed-power Z-machine, enabling us to conduct this unique experiment."


The pulsed-power machine at the Sandia National Laboratories in New Mexico (similar in concept but larger than the University's Nevada Terawatt Facility Zebra accelerator) is the most powerful source of X-rays on earth, Mancini said.


"We subject a very small cell – a 1-inch by ½-inch cube – filled with a gas, such as neon, to this tremendous, short burst of X-ray energy," he said. "It's about 10 nanoseconds of the most intense power on earth – creating conditions of hundreds of thousands of degrees and millions of atmospheres in pressure – in the form of X-rays."


The researchers can then compare their extensive computer modeling and calculations with the measurements so they can study and explain the extreme state of matter (plasma) created during those 10 nanoseconds, which mimics the majority of matter found throughout the universe.


"We are using a unique imaging X-ray spectrometer to measure the intensity distribution of radiation as a function of wavelength, which tells us what happens with the plasma," Mancini said. From detailed analysis of the data, Mancini can extract the plasma's density, ionization and temperature.


He said the plasma reaches extreme conditions, very unlike the low-energy plasma found in a neon light or a plasma television screen, with light 1,000 times more energetic than visible light, temperature as high as 100,000 degrees Fahrenheit, and ionization mainly driven by the action of the X-ray flux going through the plasma.


The University of Nevada, Reno Physics Department has a team of about 20 scientists, faculty and research associates working on a variety of projects in the field of High Energy Density Plasma Physics Research. Mancini emphasized that having strong research programs is critical for the quality of education and training that the University can provide to students.


end quoted







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