## The History of Gravity

A long time, scientists tried to understand the motion of celestial bodies. During the Middle Ages, scientists and philosophers believed in the geocentric astronomical model, where the Earth was the center of the Universe, with the planets, the Sun and other celestial bodies moving around it.

Nicolaus Copernicus (1473 – 1543) proposed the heliocentric model. This model displaces the Earth as the center of universe and place the Sun in it and the Earth and others known planets moving around of Sun. Copernicus’ shocked society and the church, which condemned his model. However, Copernicus got support of great astronomers and scientists such as Galileo Galilei and Johannas Kepler.

Galileo Galilei (1564 – 1642), using a brand new invention, the telescope, developed observational astronomy. This astronomy division is concerned in getting data of celestial bodies to create a model or theory. With the telescope, Galileo could observe celestial objects and phenomena that were not seemed before. Galileo’s discovers, such asVenus’ phases and Jupiter’s Moons, gave support to Copernicus’ model.

Even with these and other proves of heliocentric model, many astronomers still could not believe it. They condemned the Galileo telescope as evil instrument that showed unreal image of the sky.

Another support to heliocentric model came with Johannes Kepler (1571 – 1630). He calculated the orbit of the planets around the Sun, with astronomic data of Tycho Brahe (1546 – 1601), a famous astronomer of his time. Kepler created the three laws of planetary motion that get his name: Kepler’s laws.

The Kepler’s laws are:

1. “The orbit of every planet is an ellipse with the sun at a focus.”

2. “A line joining a planet and the sun sweeps out equal areas during equal intervals of time.”

3. “The square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit.”

Another support to heliocentric model came with Johannes Kepler (1571 – 1630). He calculated the orbit of the planets around the Sun, with astronomic data of Tycho Brahe (1546 – 1601), a famous astronomer of his time. Kepler created the three laws of planetary motion that get his name: Kepler’s laws.

The Kepler’s laws are:

1. “The orbit of every planet is an ellipse with the sun at a focus.”

2. “A line joining a planet and the sun sweeps out equal areas during equal intervals of time.”

3. “The square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit.”

Nature and Nature’s laws lay hid at night:

God said, Let Newton be! And all was light.

—Alexander Pope

God said, Let Newton be! And all was light.

—Alexander Pope

The last doubts about the heliocentric model were removed years later by Isaac Newton (1643 – 1727). Based on Galileo’s and Kepler’s works, Newton published “Principia” in 1687. In this book, Newton posed the theory of Gravity, in which the force that makes planets to move around the Sun is the same force that makes object to fall in the Earth: force of gravity. In his theory, Newton deduced gravity is a force of mutual interaction of body with mass and this force is inversely proportional to the square of the distance between objects.

The heliocentric model was established by Newton but there were some question about the gravity, for example, its action at a distance and immediately action. Even Newton had doubts about the gravity action at a distance. How can massive objects attract each other at distance without mediation of anything? And how can attraction force between them be immediately without a time to action?

The heliocentric model was established by Newton but there were some question about the gravity, for example, its action at a distance and immediately action. Even Newton had doubts about the gravity action at a distance. How can massive objects attract each other at distance without mediation of anything? And how can attraction force between them be immediately without a time to action?

In order to move forward into the exciting science of energy medicine (specifically PEMF therapy) with an empowering attitude of taking responsibility for our own health; we need to see why this paradigm is flawed by first looking at the basic concepts of Newtonian physics. Then we’ll introduce the exciting new physics, namely quantum field theory, and the latest developments in science.

Isaac Newton (1642-1727) is regarded as the founder of modern Western science that dominated for at least 200 years until the early 20th century with the discovery of quantum mechanics. A whole new universe opened up in the early part of the 20th century and here we are 100 years later still gazing through the tinted windows of Newton’s physics.

Isaac Newton (1642-1727) is regarded as the founder of modern Western science that dominated for at least 200 years until the early 20th century with the discovery of quantum mechanics. A whole new universe opened up in the early part of the 20th century and here we are 100 years later still gazing through the tinted windows of Newton’s physics.

Newton's law of universal gravitation states that any two bodies in the universe attract each other with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. (Separately it was shown that large spherically symmetrical masses attract and are attracted as if all their mass were concentrated at their centers.) This is a general physical law derived from empirical observations by what Isaac Newton called induction.[2] It is a part of classical mechanics and was formulated in Newton's work Philosophiæ Naturalis Principia Mathematica ("the Principia"), first published on 5 July 1687. (When Newton's book was presented in 1686 to the Royal Society, Robert Hooke made a claim that Newton had obtained the inverse square law from him – see History section below.) In modern language, the law states the following:

Every point mass attracts every single other point mass by a force pointing along the line intersecting both points. The force is proportional to the product of the two masses and inversely proportional to the square of the distance between them:[3]

## Newtonian Gravity - Force at a Distance

*F*is the force between the masses,*G*is the gravitational constant,*m*1 is the first mass,*m*2 is the second mass, and*r*is the distance between the centers of the masses.

Newton's law has since been superseded by Einstein's theory of general relativity, but it continues to be used as an excellent approximation of the effects of gravity. Relativity is required only when there is a need for extreme precision, or when dealing with very strong gravitational fields, such as those found near extremely massive and dense objects, or at very close distances (such as Mercury's orbit around the sun). Though Newtons laws work well in situations with low gravity, they are still based on inaccurate assumptions and involve the incorrect force at a distance explanation.

## Einstein's Relativity Subsumes Newton's Laws as Approximations

In 1905, Albert Einstein changed the prevailing worldview of Newtonian physics for good with the introduction of his special relativity theory, followed in 1915 by general relativity. He proved Newtonian laws of physics are by no means static, but relative to the observer and the observed. Depending on the difference in speed between the observer and the object under observation, space begins to either shrink or expand and time slows down or speeds up. Also mass increases with increasing speeds (due to increase in kinetic energy).

In Newton’s universe, there are notions of absolute space and time. Space was seen as a three dimensional stage, and time the ticking of a well-made clock. The two were separate and distinct. In Einstein’s special relativity, space and time form one 4-dimensional space-time continuum with the speed of light being the only fundamental absolute measurement. This led to the famous equation E=mc^2 showing the equivalence between matter and energy.

General relativity supplants Newton’s action at a distance with the curving of space and time. Simply put, mass curves space and curved space guides mass in a way that follows Einstein’s elegant field equations of general relativity. The force of gravity is now known to be a curving of space and time, rather than forces acting at a distance.

Einstein's Theories of Relativity are a much more refined version of Newton’s laws to take into account, relativity between observers, high speeds and intense gravitational fields (curved space).

However, Newton’s physics was “good enough” to send a man to the moon, so it is a good approximation at speeds significantly less than the speed of light and space that is mainly flat (both conditions hold in the lunar landing triumph).

In Newton’s universe, there are notions of absolute space and time. Space was seen as a three dimensional stage, and time the ticking of a well-made clock. The two were separate and distinct. In Einstein’s special relativity, space and time form one 4-dimensional space-time continuum with the speed of light being the only fundamental absolute measurement. This led to the famous equation E=mc^2 showing the equivalence between matter and energy.

General relativity supplants Newton’s action at a distance with the curving of space and time. Simply put, mass curves space and curved space guides mass in a way that follows Einstein’s elegant field equations of general relativity. The force of gravity is now known to be a curving of space and time, rather than forces acting at a distance.

Einstein's Theories of Relativity are a much more refined version of Newton’s laws to take into account, relativity between observers, high speeds and intense gravitational fields (curved space).

However, Newton’s physics was “good enough” to send a man to the moon, so it is a good approximation at speeds significantly less than the speed of light and space that is mainly flat (both conditions hold in the lunar landing triumph).

## What is Relativity?

The principle of relativity states that measurements of motion, time, and space make sense only when we describe whom or what they are being measured relative to -- there are no absolute answers.

The same is true when one person or object is accelerating with respect to the other.

Extending this general idea further, the equivalence principle states that

The effects of gravity are exactly equivalent to the effects of acceleration.

Scientific ideas for artificial gravity utilize this concept.

The same is true when one person or object is accelerating with respect to the other.

Extending this general idea further, the equivalence principle states that

The effects of gravity are exactly equivalent to the effects of acceleration.

Scientific ideas for artificial gravity utilize this concept.

## Einstein's 1st Ah-ha - All Observers Measure the Speed of Light the Same.

Special relativity unlocked the secrets of the stars and revealed the fantastic quantities of energy stored deep inside the atom. But the seed of relativity was planted when Einstein was only 16 years old and asked himself a childlike question: What would a beam of light look like if you could race alongside it? According to Newton, you could catch up to any speeding object if you moved quickly enough. If you could catch up to a light wave, Einstein realized, it would look like a wave frozen in time. But even as a teenager, he knew that no one had ever seen a frozen light wave before. In fact, such a wave makes no physical sense.

When Einstein studied Maxwell’s theory of light, he found something that others missed—that the speed of light always appears the same, no matter how quickly you move. Einstein then boldly formulated the principle of special relativity: The speed of light is a constant in all inertial frames (frames that move at constant velocity).

Previously, physicists believed in the ether, a mysterious substance that pervaded the universe and provided the absolute reference frame for all motions. But experiments to measure the “ether wind” blowing past Earth found nothing. Even if Earth were by chance motionless at one moment, there should be a discernible ether.

In desperation to save Newtonian physics, some scientists suggested that the ether wind had physically compressed the meter sticks in their experiments, thus explaining the null result. Einstein showed that the ether theory was unnecessary and that space itself contracts and time slows down as you move near the speed of light.

When Einstein studied Maxwell’s theory of light, he found something that others missed—that the speed of light always appears the same, no matter how quickly you move. Einstein then boldly formulated the principle of special relativity: The speed of light is a constant in all inertial frames (frames that move at constant velocity).

Previously, physicists believed in the ether, a mysterious substance that pervaded the universe and provided the absolute reference frame for all motions. But experiments to measure the “ether wind” blowing past Earth found nothing. Even if Earth were by chance motionless at one moment, there should be a discernible ether.

In desperation to save Newtonian physics, some scientists suggested that the ether wind had physically compressed the meter sticks in their experiments, thus explaining the null result. Einstein showed that the ether theory was unnecessary and that space itself contracts and time slows down as you move near the speed of light.

## Special Relativity - Combining Space and Time into 4D Spacetime

spacetime = 4-D combination of space and time

5d viewing of 4D --- Like Interstellar. Each 3d cube has an entire history in time. Like a panoramic life review.

The dimension of time is related to the dimension of space as distance = (time) x (speed of light).

Space is different for different observers.

Time is different for different observers.

Spacetime is the same for everyone.

--

No longer were space and time absolutes, as Newton thought. Space compresses and clocks tick at different speeds throughout the universe.

In Newton’s universe, there are notions of absolute space and time. Space was seen as a three dimensional stage, and time the ticking of a well-made clock. The two were separate and distinct. In Einstein’s special relativity, space and time form one 4-dimensional space-time continuum with the speed of light being the only fundamental absolute measurement. Measuring distance in time may seem strange but consider the following examples.

To Newton time is uniform through the universe. One second on Mars = One second on the earth. But to Einstein, time beats at different rates. The faster you travel, the slower times moves. Gravity also slows the passage of time.

In the time of pioneers distance was measured in time, for example getting from one city to another might have been agreed upon as a four days journey. Cosmologists use light-years to measure distance. For example our nearest star (besides the sun) is Alpha Centauri, which is about 4 light years from earth. 4 light years is the distance light travels in 4 years. Our moon is about 1 light second away and the sun is 9 light minutes away. When you see the sun, you are actually viewing it 9 minutes in the past. One of the illusions of space-time is that to see anything “out there” in space, you are always seeing it backwards in time. But because light travels so fast it is almost instantaneous for distances on earth, so this illusion is not apparent. To give you a sense at how fast light travels, light can take 7.5 laps around the earth in ONE SECOND!

This slowing down of time is very real and must be factored into to GPS and satellites moving relative to the earth’s surface (especially when satellites orbit in the opposite direction of the earth’s rotation.

5d viewing of 4D --- Like Interstellar. Each 3d cube has an entire history in time. Like a panoramic life review.

The dimension of time is related to the dimension of space as distance = (time) x (speed of light).

Space is different for different observers.

Time is different for different observers.

Spacetime is the same for everyone.

**Since space has three dimensions****(length, width, and height), time****can be viewed as the fourth****dimension. For example, to arrange a****rendezvous with a friend in Manhattan,****you need to give four coordinates:****“Meet me on the northeast****corner of 5th Avenue****and 42nd Street,****on the 30th floor,****at one o’clock.”****Relativity introduced****the concept of the****fourth dimension.****Imagine plotting your location on a graph, with time on the****vertical axis and space on the horizontal axis. The bottom of the graph represents the past, and the top part represents the future. If you simply sit in****one place and do****not move, you trace****a vertical line. If you start to move, you trace a vertical line that curves a bit.**--

No longer were space and time absolutes, as Newton thought. Space compresses and clocks tick at different speeds throughout the universe.

In Newton’s universe, there are notions of absolute space and time. Space was seen as a three dimensional stage, and time the ticking of a well-made clock. The two were separate and distinct. In Einstein’s special relativity, space and time form one 4-dimensional space-time continuum with the speed of light being the only fundamental absolute measurement. Measuring distance in time may seem strange but consider the following examples.

To Newton time is uniform through the universe. One second on Mars = One second on the earth. But to Einstein, time beats at different rates. The faster you travel, the slower times moves. Gravity also slows the passage of time.

In the time of pioneers distance was measured in time, for example getting from one city to another might have been agreed upon as a four days journey. Cosmologists use light-years to measure distance. For example our nearest star (besides the sun) is Alpha Centauri, which is about 4 light years from earth. 4 light years is the distance light travels in 4 years. Our moon is about 1 light second away and the sun is 9 light minutes away. When you see the sun, you are actually viewing it 9 minutes in the past. One of the illusions of space-time is that to see anything “out there” in space, you are always seeing it backwards in time. But because light travels so fast it is almost instantaneous for distances on earth, so this illusion is not apparent. To give you a sense at how fast light travels, light can take 7.5 laps around the earth in ONE SECOND!

This slowing down of time is very real and must be factored into to GPS and satellites moving relative to the earth’s surface (especially when satellites orbit in the opposite direction of the earth’s rotation.

## Special Relativity Part 2 - Matter and Energy Equivalence E=mc^2

Also, energy and matter were two distinct notions in Newton’s mechanics, and there were separate conservation laws for both: the conservation of matter and the conservation of energy. Einstein with his famous equation E = mc2 forever changed this notion as well. Matter and energy are interchangeable with energy being the more fundamental unit. This is one of the most important new scientific notions in this book that we can apply to new understandings of the human body; namely that we are primarily energetic beings and secondarily physical ones!

## Einstein's Second Ah-ha - All Things Fall to the Ground with the Same Acceleration

This famous result in physics was first discovered by Galileo who legend has it dropped two balls of different masses from the Leaning Tower of Pisa and observed they hit the ground at the same time. Whether that actually happened or not, the important point is that Galileo knew what the outcome would be.

The real triumph of this fact was seen in 1971 when David Scott, the Apollo 15 commander, dropped a feather and a hammer on the moon and both hit the ground at the same time. We cannot do that experiment on earth, because the feather experiences a air resistance due to the earth’s atmosphere (the moon has no atmosphere, so no air resistance).

The important fact is that everything falls at the same rate if air resistance can be removed.

This led Eistein to the formulate the famous Principle of Equivalence – The effects of gravity are exactly equivalent to the effects of acceleration.

Starting with the idea of the Principle of equivalence, Einstein spent 10 years of his life developing a new theory of Gravity that is to this day, still the best theory we have on Gravity.

The real triumph of this fact was seen in 1971 when David Scott, the Apollo 15 commander, dropped a feather and a hammer on the moon and both hit the ground at the same time. We cannot do that experiment on earth, because the feather experiences a air resistance due to the earth’s atmosphere (the moon has no atmosphere, so no air resistance).

The important fact is that everything falls at the same rate if air resistance can be removed.

This led Eistein to the formulate the famous Principle of Equivalence – The effects of gravity are exactly equivalent to the effects of acceleration.

Starting with the idea of the Principle of equivalence, Einstein spent 10 years of his life developing a new theory of Gravity that is to this day, still the best theory we have on Gravity.

Why do things fall at the same rate and why is it such a big deal?

Imagine you are standing in a stationary elevator. Your feet are firmly pressed on the floor, your head pushes on your shoulders and your stomach rests securely inside your body.

Now imagine you are in an elevator with the cord cut (don't worry, there is a big spring at the bottom of the fall). Since everything falls at the same rate, your feet no longer push on the floor, you head is no longer pushing on your shoulders, and your stomach floats freely in your body. In short you are weightless. It's as if gravity was turned off! An astronaut floating in space would feel exactly the same.

To be more precise, there are no experiments you could inside the falling elevator that would distinguish whether you were falling in the elevator or floating in space. Of course you would know the difference since you walked into the elevator, but that is not the point. The point is that the laws of physics are the same in both situations. This is why it is called the principle of equivalence.

The effects of gravity are exactly equivalent to the effects of acceleration.

Imagine you are standing in a stationary elevator. Your feet are firmly pressed on the floor, your head pushes on your shoulders and your stomach rests securely inside your body.

Now imagine you are in an elevator with the cord cut (don't worry, there is a big spring at the bottom of the fall). Since everything falls at the same rate, your feet no longer push on the floor, you head is no longer pushing on your shoulders, and your stomach floats freely in your body. In short you are weightless. It's as if gravity was turned off! An astronaut floating in space would feel exactly the same.

To be more precise, there are no experiments you could inside the falling elevator that would distinguish whether you were falling in the elevator or floating in space. Of course you would know the difference since you walked into the elevator, but that is not the point. The point is that the laws of physics are the same in both situations. This is why it is called the principle of equivalence.

The effects of gravity are exactly equivalent to the effects of acceleration.

## General Relativity - Explains Gravity

Special relativity was incomplete because it made no mention of acceleration or gravity. Einstein then made the next key observation: Motion under gravity and motion in an accelerated frame are indistinguishable. Since a light beam will bend in a rocket that is accelerating, a light beam must also bend under gravity.

To show this, Einstein introduced the concept of curved space. In this interpretation, planets move around the sun not because of a gravitational pull but because the sun has warped the space around it, and space itself pushes the planets. Gravity does not pull you into a chair; space pushes on you, creating the feeling of weight. Space-time has been replaced by a fabric that can stretch and bend.

General relativity can describe the extreme warping of space caused by the gravity of a massive dead star—a black hole. When we apply general relativity to the universe as a whole, one solution naturally describes an expanding cosmos that originated in a fiery big bang .

To show this, Einstein introduced the concept of curved space. In this interpretation, planets move around the sun not because of a gravitational pull but because the sun has warped the space around it, and space itself pushes the planets. Gravity does not pull you into a chair; space pushes on you, creating the feeling of weight. Space-time has been replaced by a fabric that can stretch and bend.

General relativity can describe the extreme warping of space caused by the gravity of a massive dead star—a black hole. When we apply general relativity to the universe as a whole, one solution naturally describes an expanding cosmos that originated in a fiery big bang .

## Curved Space

To see how curved space causes the apparent attraction of gravity, imagine two planes taking off on parallel lines (think of longitude or meridians) heading towards the North pole. As they travel it appears they are moving closer to each other by some mysterious force. But this illusion is only a result of the earth being a curved space. Simillarly, what we call gravity was shown by Albert Einstein to be a result of the curving of a space, not a mysterious force from a distance.

## Bringing Space, Time, Energy and Matter all Together!

1915-1916 - General Relativity - Allowed Einstein to explain gravity in a much wider context with speeds approaching the speed of light and very massive objects

Einstein's General Theory of Relativity further unified spacetime with matter-energy in a new theory if Gravity.

Energy-mass tells spacetime how to curve and curved spacetime tells mass how to move. So Einstein's field equations now show an equivalence between curved and warping space and energy-matter density.

Einstein's General Theory of Relativity further unified spacetime with matter-energy in a new theory if Gravity.

Energy-mass tells spacetime how to curve and curved spacetime tells mass how to move. So Einstein's field equations now show an equivalence between curved and warping space and energy-matter density.

## General Relativity - Field Equations (Actually 10 Equations)

## Stress Energy Tensor - Shows Matter - Energy Equivalence

## Mass-Energy Curves Spacetime and Curved Spacetime Guides Mass-Energy Giving Rise to Gravity

The curvature of space near a massive object (e.g. Sun) forces the light beam passing near it to bend, much like a lens.

Changes in angular separation between stars were measured to change near the Sun during the solar eclipse in 1919 by Sir Arthur Eddington.

Trajectories of light from distant stars or galaxies are bent by the gravitational field of a massive object located along the line-of-sight, producing multiple images or a ring of images (read Einstein's 1936 Science paper on gravitational lensing).

Changes in angular separation between stars were measured to change near the Sun during the solar eclipse in 1919 by Sir Arthur Eddington.

Trajectories of light from distant stars or galaxies are bent by the gravitational field of a massive object located along the line-of-sight, producing multiple images or a ring of images (read Einstein's 1936 Science paper on gravitational lensing).

## Proof of Einstein's General Theory of Relativity

Mercury's orbit slowly precesses around the Sun.

cannot be explained by Newton's law of gravity.

Time runs slower and space is more curved on the part of Mercury's orbit that is nearer the Sun.

cannot be explained by Newton's law of gravity.

Time runs slower and space is more curved on the part of Mercury's orbit that is nearer the Sun.

First, our technology would fail. The Global Positioning System (which locates our position on Earth to within 50 feet or less) would malfunction, because the clock on the satellite does not tick at the same speed as Earth clocks. Moreover, since relativity governs the properties of electricity and

magnetism, all modern electronics would come to a halt, including generators,computers, radios, and TV.

Without correcting for the effects of relativity, the GPS signals would have errors of several parts per billion, enough to make them useless.

magnetism, all modern electronics would come to a halt, including generators,computers, radios, and TV.

Without correcting for the effects of relativity, the GPS signals would have errors of several parts per billion, enough to make them useless.