The writings of R. Anthony Saritelli Riverside, Rhode ...



E Pluribus Unum and How It Affects Time & Gravity: A New Proposal!…One bloodOne Life…You got to do what you should.One life, With each otherSisters, BrothersBut where not the sameWe get to carry each other, carry each other!One life….One!------------U2Addendum to Author’s Maverick Thoughts on Time & Gravity in our Ever-Expanding Universe.What is gravity? Isaac Newton never defined what it was just how it manifested itself. He called it a force without ever explaining the term nor how it imparted its effect instantaneously on another mass even at a great distance. He wrote to answer his contemporary critics in the 3rd edition of Principia; “I have not as yet been able to deduce from phenomena the reason for these properties of gravity and I do not feign hypotheses.” He simply described it as a universal force that at its simplest presentation between only two objects depended only their masses and on the inverse of the square of the distance between them. Gottfried Leibnitz of Germany, an intellectual contemporary who independent of Newton’s mathematical effort developed the framework of calculus, complained that “without any mechanism…[gravity] is an unreasonable and occult quality.” Galileo’s observation that everything falls with the same acceleration gave Einstein some new insights: a frame of reference in freefall is equivalent to a frame with zero gravity. An accelerating frame of reference is equivalent to a gravitational field. Einstein used these insights to derive gravitational redshift and time dilation. The realization that a falling man won’t feel his own weight provided the crucial hint that led Einstein to think about gravity along similar lines to those he used to analyze the relativity of time and space. A free-falling frame is an inertial frame of reference. An apple falling accelerates like anything else that falls with it. A GoPro camera falling with the fruit would appear to not see, notice or photograph the acceleration at all. The picture would show a frame of reference where gravity is zero. Without a push from an outside force both falling objects appear to move at constant velocity and from that frame of reference that is visually what will be recorded. If you are at a fruit stand and drop an apple it accelerates downward towards the floor due to gravity. It doesn’t have to be pushed downward to accelerate is not an inertial frame. An inertial frame demands an external force be applied otherwise an object does not accelerate. The inertial frame of free fall and the stationary frame of the fruit market are not the same circumstances, and the measured difference between them is the acceleration of gravity. Gravity is just an effect of inertia in a reference frame that is not inertial; free-fall near the Earth is a contrarian anomaly, a recess from the physics of non-inertia. Free bodies accelerate near Earth whereas free bodies move in straight lines at uniform speed where the principle of inertia holds. Likewise, in a closed room, it is not feasible for one to determine whether the feel of one’s own weight pushing up from the floor is from being entwined in a gravitational field or a rocket motor accelerating upward. Free fall in a gravitational field produces the same experience as the weightlessness of the furthest reaches of empty spaces; acceleration produces the same sensation of weight as one standing on the surface of a planet with a massive gravitational field. Within each pair of phenomena is equivalence. Einstein’s great advance came when he realized that acceleration and gravity affect the flow of time: four-dimensional space-time would have to bend too, as even the dimension of time flexes under the influence of gravity. Gravity is a property of matter and energy [not matter alone, as in Newton’s opinion] that bends time. Mass is a source of gravity, but energy has mass too. A swinging pendulum is minutely heavier than one at rest because the kinetic energy of the weighted pendulum through its period has slightly more mass. As a moving object with mass approaches the speed of light its mass increases precipitously. The mass of the energy needed to boil enough water to cook half a pound of macaroni can be measured in a few dozen picograms, but it gravitates too. The total amount of mass and energy at a set location determine the strength of the gravitational field, and hence the amount any given region of space-time will flex. Space-time is no mere staging, merely a sideshow to the structure of the Universe; rather it is active and dynamic, its very shape determined by what it contains, demonstrating that ‘the foundation of geometry has physical significance.”According to Einstein, Newton’s force of gravity is as fictitious as when people walking due north walk following parallel meridians on Earth come closer together as if drawn together by some magical attraction whereas it is their course ‘over the Earth’ that directs them towards one another because the Earth is a sphere and because its surface is curved. Walking parallel lines northward on a sphere with positive curvature leads to a convergence due to geometry. Imagine two small balls, separated horizontally by some distance, falling freely towards the Earth. From Newton’s perspective, each ball accelerates towards the center of the Earth because the force of gravity acts along a straight line drawn from the center of the earth to the center of the ball. This means that the two balls must get closer together as they fall, because they each fall along straight lines that meet at the center of the earth. So how can two balls get closer together when they are experiencing no force? The geography they are moving on is not flat, and because of the curvature they are moving closer together as they move. If they were following parallel lines on a hyperbolic shape like a saddle in time the parallel lines would diverge.Einstein had the idea that no forces act on an object in freefall. The force of gravity is a fictitious force; it is just the manifestation that spacetime is curved. The beauty of Einstein’s General Theory of Relativity is in part due to the simplicity of its core idea: that objects move over a curved spacetime in the straightest path—the shortest path between two points on a curved surface. The shortest route between two distant points on a globe is also a section of a great circle. These ‘straight’ lines on a sphere become distorted when projected on a flat map where east-west distances are shorter than they appear far north or south of the equatorial great circle. The shortest path between two points on a sphere appears curved on a flat map projection. The trajectories of different motions described by Newton as paths inscribed by forces—free fall, elliptical orbits, parabolic projectile arcs---according to Einstein are the straightest paths in a curved spacetime. A gravitational trajectory near the Earth follows the geodesic of curved spacetime. The trajectories of all free-falling bodies whether they are falling apples or orbiting satellites around Earth are exclusively spacetime geodesics. And, it is the presence and amount of matter and energy that warps spacetime. We can use Einstein’s equations to compute the warping of spacetime close to the Earth’s surface with the results being almost identical to Newton’s. Soon after Einstein published his theory in 1915, two of his predictions that differed from Newton’s were tested. One concerned the orbit of Mercury, which is not well described by Newton’s laws and had been a known problem for almost two centuries. The anomaly that the French mathematical astronomer Urbain-Jean-Joseph Le Verrier found is called the precession of the perihelion of Mercury’s orbit. In the squashed circle of an elliptical orbit, the point at which a planet comes closest to its star is its perihelion. In an idealized two body system, that orbit is stable, and the perihelion remains fixed, always coming at the same point in the annual cycle. Once you add more planets that constancy evaporates. In a multi-bodied system [> 2] if you were to map each year’s track onto a single sheet of paper, you would over time draw a flower petal, with each oval just slightly shifted. When the shift comes in the same direction as the annual revolution is said to advance. Mercury’s perihelion advances at a rate of 565 arcseconds every 100 years. Next came a celestial bookkeeping: how much of that total could be explained by the influence of other planets on Mercury. Venus, as Mercury’s neighbor, proved to be doing most of the work. Le Verrier’s sums revealed that it accounted for almost half of the precession, 280.6 seconds of arc per century. Jupiter provided another 152.6 seconds to the ledger, Earth 83.6, with the rest just minute contributions. The total accounts for 526.7 arcseconds per century so Mercury’s perihelion landed just 0.38 [1859 calculation of discrepancy: modern day value-0.43] seconds of arc ahead of where it should every year. It progresses at a rate that cannot fully be accounted for by any combination of forces within the solar system. By 1915, Mercury’s variant orbit had been known in detail thanks to Le Verrier’s endeavors and the observation of the transit of Mercury in 1845 for over seventy years:November 18, 1915: “Masking his emotions behind the required decorousness of scientific communication, Einstein revealed almost no sign of excitement in his presentation to the Prussian Academy. “The calculation for the planet yields,” he told his audience, “a perihelion advance of 43 arcseconds per century, while the astronomers assign 45 seconds + or – 5 seconds per century as the unexplained difference between observations and the Newtonian theory...this [new] theory agrees completely with the observations.” The Sun with its great mass creates its dent in space-time. Mercury so firmly embraced by the Sun’s gravitational field, lies deep within that solar gravity well. Like all objects navigating space-time, Mercury’s motion follows that warping, four-dimensional curve, and the orbit of the innermost planet precesses away from the Newtonian ideal. Farther out, the Sun’s influence on local space-time moderates, & the orbits of the other planets approach the Newtonian approximation.”The Hunt from Vulcan: …And How Albert Einstein Destroyed A Planet, Discovered Relativity, & Deciphered the Universe by Thomas Levenson*The other opportunity for testing the new theory was Einstein’s prediction for the amount by which light is deflected in a gravitational field, which differed from Newton by a factor of two. Einstein’s result was confirmed during the solar eclipse of 1919, when starlight was observed passing the ring close to the Sun, and this was the moment he became world famous. Einstein’s theory of gravity, General Relativity, supersedes Newton’s because it delivers a more accurate description of Nature. Einstein understood that both mass and energy contribute to gravity. The gravitational field around any star or planet is really a field of time distortion. But the ultimate test of any new theory lies with its predictions: general relativity made several that were testable with the technology on hand in the early 20th century. It claimed that the Sun’s mass bends light by an amount double that predicted by Newton’s theory, 1.7 arcseconds compared to 0.87 arcseconds. The eclipse would come on May 29, 1919 where British scientists in two teams set out: one travelling to Sobral in Brazil, and the other to Principe, a tiny island off the West African coast in the Southeast Atlantic. Lead astrophysicist Sir Arthur Eddington reached the island in late April making control pictures of the night-sky of the star-field that would be visible around the eclipsed Sun. On May 29th at dawn torrential rain down-poured, which eased by mid-day and at 1:30 pm the observational team had their first glimpse of Sun, already well within the partial phase of the full eclipse. They took 16 exposures through clouds that thickened and cleared; just six of which proved clear enough for further examination. Four of the six had to be developed back in England. Of the remaining two, only one was with clear enough skies to permit preliminary analysis in the field. It took Eddington four days, but on June 3, he was able to make his first comparison to the test images to the star positions recorded in the eclipsed sky. He found the answer he sought: a deflection of 1.61 arcseconds of arc, plus or minus 0.3—close enough to Einstein’s predicted result to claim confirmation. His telegram from Principe: “Through cloud, Hopeful, Eddington.”At Sobral in South America, the weather had been fine there, and that team made several more useful photographs. When they were analyzed they seemed to claim only half the deflection claimed at Principe: Newton’s original answer. The next month, Eddington & his colleagues confirmed that the primary Sobral instrument had an optical defect that systematically produced errors in its results. Ignoring the contradiction, he alerted the British Royal Society of his findings and how it buttressed Einstein’s new theory. **Time and motion are not absolutely defined according to Albert Einstein. Measures of time are simply different for observers in motion relative to one another due to Einstein’s principle of relativity. Time dilation goes beyond clocks to the nature of time itself. Remember that it is said that a moving clock runs ‘slower’ than a clock ‘at rest’. Time and ticking clocks run slower in a rocketing spaceship but an astronaut aboard would not notice any slow-motion effect. All physical effects happen normally. More precisely, imagine the time between two events occurring at different locations in the same frame of reference measured by two separate clocks positioned at each location. This time interval will be more than that measured by a single moving clock that is carried along to be present at both events. The measured time on the onboard clock will be less than by that counted by the pair of positioned clocks. Clocks close to the center of a gravitational field run slower too. Einstein’s equations predict that time passes more quickly at the top of a mountain than at its bottom; remember that both space & time are warped by the presence of Earth, not just space. From Einstein’s equations one can predict that an earthbound clock loses one microsecond every three hundred years. A clock on the prototypical neutron star ticks along 30% slower than one here on Earth due to its crushing density. If one could compress the mass of the Earth within a 1.8 cm diameter sphere time would mysteriously stand still. There is an equivalence between moving clocks and those stationary in a deep gravitational field. Acceleration and gravity can be theorized as equivalent if the time measured in both similar frames of reference ticks by at the same rate. It is gravitational time dilation near the surface of the Earth that keeps the straightest path, the inertial path of the accelerating fallen apple, from being a downward motion at a constant velocity. It is the time effect that is critical for the gravity that we experience where objects accelerate faster as they plunge downward toward the center-point of a gravitational mass. On Earth one may not feel the motion, but you are moving rapidly through Space on the surface of a non-inertia frame of reference that is accelerating. Over one person’s lifespan, galaxies and most stars appear motionless, they are not only receding from, us---but the more distant galaxies and stars are receding proportionately faster. Galaxies are moving in that they rotate internally, are attracted locally being pulled by their neighboring galaxies and are moved by the catholic cosmic expansion. A ball dropped from above accelerates to its surface at a speed that is proportionate to the magnitude of its inertial lag as compared to that of the massive Earth as it moves through the Universe. Freefall in a gravitational field is equivalent to being weightless in a gravity-free remote part of our expanding Universe. Clocks run faster in a gravitational free, inertial frame where things only move along at an unimpeded rate of speed when pushed by an external force. Clocks run faster the further they are removed from a source fueling an objects acceleration including gravity. Fast ticking clocks shrink units of time but register more elapsed time. Slow clocks lengthen units of time but record less time. Time dilation where each clock tick is slower due to the gravitational mass of the Earth allows for the moving Earth to cover a greater distance in its travels compared to that of those smaller masses that exist where clocks run faster further away from any strong gravitational force. Faster clock ticks curtail the distance moving bodies travel in a measured interval of time. Mass distorts the curvature of spacetime allowing for more massive objects additional time to move along and outward as the Universe increasingly expands; its benefit evident in the ever-increasing complexity of matter and the organizational hierarchy of systems in motion within the Cosmos. E Pluribus Unum: Latin meaning out of many, one. ‘One out of many’ creating gravitational fields that slow down time at the local level, allowing for the bigger galaxies and galaxy clusters to cover more distance than smaller bodies as the Universe expands outward at an ever-increasing rate. ‘One out of many’ contributes to the interplay of heavenly bodies and energies that define what we know as gravity.By Robert A. Saritelli 10/19/2018References:Levenson, Thomas: The Hunt for Vulcan: …And How Albert Einstein Destroyed A Planet, Discovered Relativity, & Deciphered the Universe. Random House-New York—2015Schumacher, Benjamin: The Great Courses: Black Holes, Tides & Curved Spacetime: Understanding Gravity; Course Guidebook. Chantilly, Virginia. 2013.Davies, Paul; How to Build A Time Machine. Viking Penguin. 2002. ................
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