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JPL discovered a strange anomaly in the velocities of spacecraft that used the Earth to provide a gravity boost to help the spacecraft reach their ultimate objective. An intro on the flyby anomaly, from the Planetary Society: http://www.planetary.org/news/2008/0228_Researchers_Investigate_New_Cosmic.html 28 February, 2008. A new study by researchers from the Jet Propulsion Laboratory shows that spacecrafts that swing by the Earth are subject to a small but unexplained increase in their velocity. Is an unknown physical force at work, or something far more mundane? Some exotic explanations were proposed, including General Relativity (see the above article), the Unruh effect, ... (McCulloch, M.E., "Can the flyby anomalies be explained by a modification of inertia?", submitted 18 Dec 2007 to arxiv.org) and dark matter (Adler, S.L., "Can the flyby anomaly be attributed to earth-bound dark matter?", submitted 19 May 2008 to arxiv.org). The answer is probably a lot more mundane: It is probably just sloppy math (Mbelek, J.P., "Special relativity may account for the spacecraft flyby anomalies", submitted 11 Sep 2008 to arxiv.org). In the following, we show that SR transverse Doppler shift together with the addition of velocities are sufficient to explain the flyby anomalies. Thus, GR does not need to be questioned and the flyby anomaly is merely due to an incomplete analysis using conventional physics. Ooops. This last article, BTW, is amazingly brief and to the point.

Now that we know the OPs true colors, is there any reason you have not moved this thread to its rightful home, Bignose?

Let's go back to the start. North, you seem to have a misconception of what a black hole is and in particular, what an event horizon is. From these misconceptions you have leapt to some erroneous conclusions. A black hole is a concentration of mass in a very small volume, so small that at sufficient proximity the escape velocity exceeds the speed of light. This surface inside which even light cannot escape the black hole is the event horizon. For a non-spinning black hole the event horizon is a sphere, and very small sphere at that. This is your first misconception. A black hole is small. The event horizon for a stellar black hole with a mass of five solar masses is a mere 30 kilometers across. Even a supermassive black hole is tiny. The black hole hypothesized to exist at the center of the Milky Way, with a mass of 4 million solar masses, is 25 million kilometers in diameter. That might sound big, but it's not. That black hole would fit inside the orbit of Mercury. Forget about the gravitational issue for a bit. Suppose there exists some exotic object that has absorbs all light that hits it but has very little mass. Now imagine one of these objects 25 million kilometers across at the center of some galaxy. Could we see any signs of this object if we aimed a telescope on that galaxy? No. It's too small. Seeing that object would be akin to seeing a grain of dust flying in front of the sun. Even worse, it would be akin to seeing a grain of dust flying behind the sun. Your second misconception is that stuff about jets and a "two point event horizon". The event horizon for a non-spinning black hole is a sphere, not a pair of isolated points. Things get a lot trickier for spinning black hole, but the event horizon is still an oblate spheroid. Infalling matter toward a spinning black hole will form an accretion disk, somewhat similar to the way a star system forms. (Look at our solar system; the planets all orbit in roughly the same plane.) The jets you are talking about do not come from the black hole itself (nothing escapes a black hole); they come from the accretion disk and are directed along the accretion disk axis. Since we can't see black holes, even supermassive ones, how do we detect them? One way to detect black holes is by means of the radiation given off by the accretion disks, particularly the jets. Another way is to look at stars at the center of a galaxy. Suppose astronomers detect a star closely orbiting something at the center of some galaxy. They can infer the mass of that thing the star is orbiting from the nature of the star's orbit. We know there is some very small object at the center of our galaxy with a mass of 4 million suns. A supermassive black hole is one possibility. Any other candidates made of stuff we know (e.g., a bunch of neutron stars) could not exist in that proximity and fail to form a black hole. So that thing in the center of our galaxy is a supermassive black hole, or something like nothing else we know of in the universe.

it is important to note that all reference frames are equally valid. One can do physics entirely from the perspective of an Earth-fixed, Earth-centered reference (i.e., a frame with origin at the center of the Earth and rotating with the Earth). An ECEF reference is exactly what you want to use if you are modeling the Earth's atmosphere. It is of course exactly what you don't want to use if you are modeling the dynamics of some extrasolar star system. While all reference frames are equally valid, some reference frames are incredibly dumb choices for use in solving a particular problem and some are very good choices. Which frame is "best" depends on the problem at hand. So, Is the Earth rotating? This begs a question: Rotating with respect to what? I'll assume you are talking about rotation with respect to some non-rotating frame. That in turn begs another question, what the F is this "non-rotating frame" business? Classical and general relativity have different concepts of what constitutes an inertial frame. Since we're talking about earhly motion, I'll use the classical definition: A non-rotating frame is a reference frame in which one only needs to account for the acceleration of the frame origin to make Newton's Laws appear to be valid. A non-rotating frame in classical mechanics is also a non-rotating frame (locally) in GR. So, how can we tell if the Earth is rotating (with respect to inertial space)? Obelix, you missed one obvious test: The Sun. moon, and stars. We know how far the Sun, moon, and planets are from the Searth thanks to many different measurements, all of which agree with one another. Pluto's velocity, as measured by an Earth-fixed observer, always exceeds the speed of light. We can measure the distance to some stars by means of parallax. Even the closest star has an apparent velocity of 9,000 times the speed of light and is undergoing a near constant magnitude acceleration of 200,000 kilometers/second2 toward the Earth. The problems with these non-physical velocities and accelerations disappear as soon as one incorporates the Earth's rotation into the mix.

For those who do not know what IA is talking about here, take a quick perusal of the posts made by the original poster. Here is a handy link to those posts. Pick and choose, but make sure you don't have any liquids of any sort in your mouth. Consider yourself warned: I hereby disclaim all responsibility for any monitors sprayed with soda.

The problem is that Obelix couched the question in religious fundamentalist terms. He started the original post with a link to a crackpot site and ended it with further references to them. He invited the off-topic discussions by framing the original post in exactly the same manner that crackpots use in their opening posts. Swansont even felt forced to edit the OP to "turn the volume down". The posts that deride pseudoscience wouldn't have been made and the thread would not have been moved into pseudoscience had Obelix simply asked "what experiments other than the Foucault's pendulum demonstrate that the Earth is rotating" and kept it at that (which he is invited to do in another thread). He didn't do that. There was no reason to bring the nut cases into play (and these people are nuts; the vast majority of religious people do not ascribe to anything approaching these views).

No. The Earth and Moon orbit about their center of mass, the position of which is inside the Earth (as has been previously noted). The Earth and Moon do not orbit any the Lagrange points (also called Lagrangian points and libration points). There five such points, none of which is located at the point "where gravity is equal between the earth and moon". The Lagrange points are points of equilibrium in the "circular restricted three body problem". One of the Earth-Moon Lagrange points, L1, is located between the Earth and the Moon, but it is a bit closer to the Earth than is the "point where gravity is equal between the earth and moon". This latter point is of very little interest. Both the L1 point and this neutral point are located a lot closer to the Moon than they are to the Earth.

Why all the detailed math for something that is intuitively obvious? Take a laser projector, mount it on a pivot, aim it at the moon, and rotate the laser so the beam sweeps across the face of the moon. All it takes is a paltry 1/8 RPM rotation rate of the laser to make the swept beam appear to cross the face of the Moon at the speed of light. Rotate the laser faster than 1/8 RPM and swept beam will exceed the speed of light. Does this violate relativity? Of course not. A person on the Moon could not use the laser beam to communicate with another person on the Moon.

Bohr axiomatized this radiation away. The biggest shortcoming of the Bohr model in my mind is not the radiation (it doesn't happen in the Bohr model) but its limited applicability. It fails to explain details like the fine structure and it fails miserably when applied to nuclei with more than one electron.

Science is not about beliefs. It is about evidence. The evidence is that Bohr model fails badly when applied to anything but the hydrogen atom. It is a fundamentally flawed model.

If you assume a constant density, you should be able to solve this yourself. All it takes is some simple high school algebra. I'll give you a start. The surface gravity of a constant density sphere of radius R is [math]g=\frac {G M}{R^2} [/math] where M is the mass of the sphere and G is the universal gravitational constant and has a numerical value of 6.67300×10-11 meters3/kilogram/second2. The mass of a constant density sphere of radius R is [math]M = \frac 4 3 \pi \rho R^3[/math] Where [math]\rho[/math] is the density of the sphere. The density of iridium is 22.56 grams/cm3, or 22,560 kilograms/meter3.

Jerry, While you claim you are old, but you certainly are not so old as to have been taught the Bohr theory is anything but an obsolete scientific theory. It does an OK job of modeling transitions in hydrogen atom. It is not even a particularly good picture of the hydrogen atom. You start on a bad footing and go downhill fast.

That is exactly correct. The difference in gravitational acceleration is very small, decreasing by about 3.1×10-6 m/s2 for every meter above the surface. This is the free-air correction to gravity. For the air pressure at the top of a mountain, the correction for altitude is even smaller because there is mountain rather than air between the top of the mountain and the mean surface of the Earth. In short, gravity is not the cause of the decrease in pressure. Imagine building a cylindrical column 11 kilometers tall. The air at any point in the column must buoy the weight of all of the air above that point. This buoyant force comes from compression, or pressure. The pressure must increase from the top of the column to sea level to buoy the increasing mass of all of the air above some point in the column.

Bernoulli's principle is not a law of physics like conservation of energy. Bernoulli's principle derives from conservation of energy assuming an inviscid fluid undergoing laminar flow at low Mach numbers. The flow around an inverted wing is anything but inviscid or laminar. Conservation of energy does of course apply, but Bernoulli's principle is an improper expression of conservation of energy for inverted flight. In inverted flight, it is the bottom of the wing that does the bulk of work in diverting the airflow downward. Bernoulli's principle is approximately correct for normal subsonic flight when it is the upper surface of the wing that does most of the work in diverting the airflow downward. Even for normal flight, Bernoulli's principle is to me but a hand wave: It begs the question as to why airflow is faster along the upper surface of the wing. By the time you get to a valid explanation for this effect (e.g., via the Coanda effect, the Kutta condition, onset of turbulence), you have already arrived at the fact that a wing diverts airflow downward.

You are applying the relationship incorrectly; it is not linear. The bulk modulus is defined by [math]K = -V\,\frac{\partial P}{\partial V}[/math] Assuming a constant bulk modulus, this leads to [math]V(P) = V_0\,e^{-P/K}[/math] or [math]\rho(P) = \rho_0\,e^{P/K}[/math]

If this thread isn't pseudoscience, nothing is. Moved.

Iridium's bulk modulus is 320 gigapascal at STP. The pressure at the center of the Earth is about 360 gigapascal. Ignoring temperature changes in density, ignoring that the bulk modulus varies with pressure, and ignoring that the pressure at the center of the iridium earth would not be the same as the pressure at the center of the real Earth, that bulk modulus and that pressure leads to a density three times that at STP.

Toward pure socialism, yes, I agree. That a Democratic executive and legislative branch won't make significant steps in that direction, I fully disagree. Whether this change (and that is a big part of Obama's "change") is good or bad is a different question. Why? Your argument is, IMO, overly simplistic. So are arguments from the extreme left that someone who makes 200 million is pure evil and must have that 200 million taxed at a rate 90%, minimum, because anything less would be unfair. What makes your version of fairness the correct one? Ignoring welfare, the person who makes 200 million after expenses receives proportionately much greater benefits from the government that someone who makes 200 dollars after expenses. The person who makes 200 million will have accumulated wealth that is protected from internal strife by local police and from external strife by the military. The person who makes 200 after expenses won't have much accumulated wealth in need of protection. As wealth accumulation obeys a highly non-linear relation with respect to income, if you must tax income then the only way to make it "fair" is to tax income in a progressive manner. There are a lot of problem with the word "fairness", particularly when applied to the tax code. For one thing, "fairness", like beauty, is something that varies with the beholder. For another, any form of taxation is implicitly "unfair" in the sense that it is government-sanctioned robbery. (It is not robbery in the sense that robbery impoverishes everyone but the thief while government expenditure (well, at least some of them) enrich all of us.) I like to look at things from the perspective of minimizing unfairness rather than maximizing fairness. This viewpoint results in a progressive tax code. The pain lower middle class people feels in paying ten percent of their income in the form of taxes is a lot greater than the pain wealthy people would feel if the government took only ten person of their income. Spread the pain evenly requires the rich to pay more. This viewpoint also results in all but the very poorest pay some taxes.

That is yet another erroneous application of Bernoulli's Principle. NASA's Glenn Research Center (the NASA center that researches aerodynamic flight) goes so far as to label this "Incorrect Theory #3". http://www.grc.nasa.gov/WWW/K-12/airplane/wrong3.html Let's use the information we've just learned to evaluate the various parts of the "Venturi" Theory. The theory is based on an analysis of a Venturi nozzle. But an airfoil is not a Venturi nozzle. There is no phantom surface to produce the other half of the nozzle. In our experiments we've noted that the velocity gradually decreases as you move away from the airfoil eventually approaching the free stream velocity. This is not the velocity found along the centerline of a nozzle which is typically higher than the velocity along the wall. The Venturi analysis cannot predict the lift generated by a flat plate. The leading edge of a flat plate presents no constriction to the flow so there is really no "nozzle" formed. One could argue that a "nozzle" occurs when the angle of the flat plate is negative. But as we have seen in Experiment #2, this produces a negative lift. The velocity actually slows down on the upper surface at a negative angle of attack; it does not speed up as expected from the nozzle model. This theory deals with only the pressure and velocity along the upper surface of the airfoil. It neglects the shape of the lower surface. If this theory were correct, we could have any shape we want for the lower surface, and the lift would be the same. This obviously is not the way it works - the lower surface does contribute to the lift generated by an airfoil. (In fact, one of the other incorrect theories proposed that only the lower surface produces lift!) The part of the theory about Bernoulli's equation and a difference in pressure existing across the airfoil is correct. In fact, this theory is very appealing because there are parts of the theory that are correct. In our discussions on pressure-area integration to determine the force on a body immersed in a fluid, we mentioned that if we knew the velocity, we could obtain the pressure and determine the force. The problem with the "Venturi" theory is that it attempts to provide us with the velocity based on an incorrect assumption (the constriction of the flow produces the velocity field). We can calculate a velocity based on this assumption, and use Bernoulli's equation to compute the pressure, and perform the pressure-area calculation and the answer we get does not agree with the lift that we measure for a given airfoil.

That's begs the question. You haven't explained why angle of attack makes that happen. You have just said that it does; a hand-wave. The problem with Bernoulli's Principle to explain lift is that elementary attempts to explain why the air moves faster over the upper surface fail. The most commonly used explanation, the equal transit theory, is a falsified theory. To get to some explanation of the pressure differential that does not rely on false premises you have to first arrive at the fact that an airfoil turns an air flow. So, why bother? The turning of the air flow fully explains lift.

Explain inverted flight with the Bernoulli principle.

At the center of the iridium earth, iridium would be two to three times as dense as the surface density, so assuming a constant density will overestimate the radius. What is it you want -- an iridium sphere that has 1g surface gravity, or an iridium sphere that would have the moon orbiting at one orbit per sidereal month?

Bernoulli's Principle does not explain hypersonic flight, period, and it does not fully explain subsonic flight. Even for subsonic flight, one also needs to account for the Coanda effect, vorticity, angle of attack. Bernoulli's Principle alone does not explain flight. Ultimately, if something does not result in a downward deflection of the airflow there will be no lift. Newton's third law. Excerpts from some references (click on the hyperlink for the full article): http://user.uni-frankfurt.de/~weltner/Flight/PHYSIC4.htm The conventional or standard explanation of aerodynamic lift states the higher streaming velocity at the upper side of the airfoil as cause of the lower pressure, due to Bernoulli’s law. But a higher streaming velocity is the effect of a lower pressure and never its cause. The cause of the aerodynamic lifting force is the downward acceleration of air by the airfoil - which depends on the angle of attack and its velocity. http://www.aviation-history.com/theory/lift.htm Many ask the simple question "what makes an airplane fly"? The answer one frequently gets is misleading and often just plain wrong. We hope that the answers provided here will clarify many misconceptions about lift and that you will adopt our explanation when explaining lift to others. We are going to show you that lift is easier to understand if one starts with Newton rather than Bernoulli. We will also show you that the popular explanation that most of us were taught is misleading at best and that lift is due to the wing diverting air down. http://www.grc.nasa.gov/WWW/K-12/airplane/lift1.html Lift occurs when a moving flow of gas is turned by a solid object. The flow is turned in one direction, and the lift is generated in the opposite direction, according to Newton's Third Law of action and reaction. Because air is a gas and the molecules are free to move about, any solid surface can deflect a flow. For an aircraft wing, both the upper and lower surfaces contribute to the flow turning.

I think you are giving the OP far too much credit here. He explicitly says "For an electrical universe, everything could be described in electrical terms." In short, he is trying to revive the debunked electrical universe hypothesis. That mass, however, arises the strong force, not electromagnetism. The OP makes no mention of the strong force, or the weak force, or the Higgs mechanism. If you read some of the OPs other posts you will see he is very explicit in stating that mass is charge, and charge only. He has yet to explain why leptons (or quarks) of two generations with the same charge and spin have different masses or why leptons are much less massive than baryons.

What tables of conversions? Certainly there does not. Please explain this chart in terms of your theory.