Finding Coherence with Gravity, Grounding & Gait

Part 1: A Brief History of Gravity

Gravity gets a bad rap. Too often demonized as the source of many people’s woes, it commonly takes the heat for people’s issues with balance and posture, as well as other elements of physical and psychological angst. Statements such as “gravity’s incessant pull…” or “the gravity of the situation…” each invoke images that gravity is physically causing issues or that the situation is extremely important or serious—and often negatively so.

Since human upright stance is an unstable condition (1), gravity’s influence on our balance and “posture” certainly cannot be denied. However, the reality is that gravity has been with us since we were first conceived and is part of what helped us evolve as an organism. Yes, gravity is “incessantly” keeping us on the surface of this planet, it absolutely influences our upright behaviors, and of course gravity is also essentially important. But it should be considered more about how our body manages its influence than it inherently being a problem. We should no more blame gravity for negative consequences of its impact on us than we should blame the Sun if we get a sunburn or a storm if it damages property. All these natural forces are what allows the Earth to continue to flourish and we should think more about how we should live with them and continue to benefit from their influences.

Gravity, by definition, is one of the four fundamental forces of nature, with a force being an interaction that causes a change to occur. These four fundamental forces of nature—strong nuclear force, weak nuclear force, electromagnetism, and gravity—govern all the interactions in the Universe, from planetary motion to subatomic particles. And of these four, gravity is not only the “weakest”, but it is the weakest by far! *, and also remains the least understood.

At its most fundamental level, gravity should be clarified from its sister concept of gravitation. The word “gravity” has been around for thousands of years, and its early use was synonymous with the word weight. Gravitation was first used by Sir Isaac Newton in the 17^th century and refers to the universal force of attraction between masses, while gravity is the Earth’s pull on an object downward towards the surface—or more specifically, towards the center of The Earth. Gravity primarily affects the vertical motion of any object with mass.

If we were to look a little deeper into what we truly understand about gravity—deeper into a topic which has been discussed, theorized, and researched since humans have existed—it becomes increasingly clear that there is even more we truly do not understand. Some of the earliest writings can be attributed to Aristotle who posited that bodies were drawn from one place to another due to their inherent nature and that they try to return to their “natural place” where they could be with other like objects. His views on gravitas were related to things being drawn to the Earth due to geocentric nature of the Universe (the Earth as the center) (1). The Greek philosopher Democritus circa 400 BC discussed the concept of atomism (from the root word “atomos” meaning “not to be cut”). He felt these were the building blocks of matter, that they were indivisible, indestructible, and infinite in number, and they were always moving and capable of joining together. It should be noted the degree of accuracy of these concepts to our current understanding of atoms, as well as the correlation to the word “attraction” and matching more closely to what modern physicists discuss as it relates to gravitation.

Leonardo da Vinci in his notebooks from the early 1500’s explored the concept of gravity as a form of acceleration (3). He wrote about “equilization of motions” as it pertains to a fluid being poured from a pitcher while it is moved along a horizontal plane. It would not be for another hundred years in 1604 that Galileo Galilei would develop his theories on gravity from his observations and experiments on rolling and falling objects of varying weight and size. He noted how the distance covered by a falling object is proportional to the square of the time elapsed, as well as observing that objects would fall at the same rate if “in a medium totally devoid of any resistance” (4). A fascinating example of this is demonstrated by the astronaut David Scott on the surface of the moon where he drops a falcon feather and a hammer at the same time and they hit the surface of the moon at the same time. He refers to Galileo’s work specifically as he conducts this experiment, thereby confirming Galileo’s theory (5,6).

Which brings us to the two more well-known names in the field of gravity science—Sir Isaac Newton and Albert Einstein. Sir Isaac Newton published his seminal work “Principia Mathematica” in 1687 in which he first introduces the concepts of forces acting upon objects—from falling objects to planetary motions. He introduces the word centripetal in his writings which means “seeking the center” (Latin, centri- meaning “center” and petere meaning to “seek” or “strive after”) and he also discusses inertia within his well-known three laws of motion** (7). This inertial force is what is needed to make objects move in a circle and can be produced by things such as friction (i.e. a car making a hard turn), tension (i.e. holding the handle of a bucket and swinging it around), and gravity. He also introduced the word gravitation in his Law of Universal Gravitation as he need to reconcile what happens with these inertial and centripetal actions. Newton fully appreciated the role of gravity in what we were experiencing, but he was the first to put the mathematics behind it and explain that gravity is a force from a more linear perspective and his equations and explanations continue to be used today.

The other heavy hitter in the field of physics and the study of gravity is Albert Einstein***, whose work has altered and expanded our understanding of physics, nature and of course gravity. He turned long-held beliefs of what we thought about gravity and the relationship between time and space on their head. He introduced his Theory of Special Relativity in 1905 in which he describes that time and space are not absolute but rather they are ‘relative’ to each other. It was also in this paper that he introduced his famous equation of E=mc2 which expresses the fundamental relationship between mass (m) and energy (E). It is applicable in ‘special’ cases when objects are moving at constant or uniform speed, that the ‘relative’ motion of two objects should be the frame of reference and the only thing matters is how fast you and the observed object are moving with respect to each other. As he speculated further about acceleration and gravity and its role in these principles, he proposed with his Theory of General Relativity in 1915 in which he posited that massive objects in space will cause warping or distortion of space-time which is what we all feel as gravity. That things are drawn or pushed towards a center by this distortion of the fabric of space (picture a weighted ball on a trampoline), that this movement is through gravitational waves, and time can be influenced as well depending on what speed one is traveling relative to this.

To simplify these concepts as they relate to—and are different from—each other:

· Newtonian physics describes how particles tend to attract other particles in the Universe. It is a force that depends only on their masses and the distance between them. It is a pull as space and time are very different things and are absolute. Its principles are linear and fixed with mass and energy being very different.

· Einsteinian general relativity suggests that gravity is a deformation of space and time and depends on energy. It is this distorted curvature on the fabric of space and time that in turn affects other matter and is essentially a push on objects with mass—part of 4-dimensional space-time. Its principles are curved and flexible with mass and energy being interchangeable (E=mc2).

To comparatively simplify these concepts even further?

· Newton

o Force

o Pulling

o Attracting

o Linear

o Fixed

o Instantaneous & infinite speed

o Mass & energy are very different

o Apples & trees

· Einstein

o Acceleration

o Pushing

o Adjusting

o Curves

o Flexible

o Relative & speed of light is the limit

o Mass & energy are interchangeable (E=mc2)

o Warping & spacetime

So how can two theories of gravity, each with such variable and differing views, both be “accurate”? The easy answer is that they both are in their own way, with both being very helpful in our understanding of the motion of objects on our planet and in the Universe. Newton’s Law of Universal Gravitation is a successful approximation and very useful for many practical applications where the effects of extreme gravity and high velocities are negligible. However, Einstein’s Theory of Relativity becomes more important when dealing with more extreme situations where increased precision is necessary, such as with strong gravitational fields (i.e. black holes), bending of light by gravity, time dilation, existence of gravitational waves and the birth and expansion of the Universe.

Whew! Some ‘heavy’ material there :) But what does all of that have to do with us and our ability to move around smoothly and stay on our feet with good balance? When we can respect that it has been literally thousands of years of thought, speculation, and experimentation from some of the greatest minds in history that has brought us to our current limited understanding within this topic, than that might allow us to better appreciate the complexity of how it influences our bodies and our lives.

While we should absolutely recognize that gravity is a ‘force’ that is ‘pulling’ us downward, we should also appreciate that it is an ‘acceleration’ that ‘pushes’ us through more curvilinear paths along the Earth. We should be less ‘fixed’ and a bit more ‘flexible’ as we flow through gravitational waves while also embracing the fact that while our perception of time does vary with every lap we take around the Sun, it is fairly constant on this planet. Yet it is time that also allows us to move forward in both our thinking and our movement and every novel experience we have helps to extend our sense of this time.

If we can better appreciate these similarities and differences, we would be doing both Newton and Einstein proud….

Part II: Gravity & Humans should provide further insight into the implications it has on how we work and move.

* Gravity is not only the weakest of the four forces which holds the Universe together, it is significantly weaker. Strong nuclear force, which governs the stability of atomic nuclei, is about a hundred times stronger than electromagnetic force, which is about ten thousand times stronger than weak nuclear force, which determines radioactive decay. Gravity? It’s about a million billion billion billion times weaker than weak nuclear force! (9)

** First Law (inertia): An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an outside (or unbalance) force. Second Law: The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass (F=ma or force=mass X acceleration). Third Law: For every action there is an equal and opposite reaction.

*** A couple of the more inaccurate depictions of Einstein are that he did not do well in school and that he worked as a lowly patent clerk as he was developing his theories of relativity. He did very well in school, with an undergraduate degree in teaching and his PhD from the University of Zurich with his dissertation on molecular dimensions. His work as a patent clerk was to evaluate patent applications—specifically electromagnetic inventions—and thus he needed to be an expert in this field of study (7).

REFERENCES

1. “An Overview of the Physiology and Pathophysiology of Postural Control”, Nardone A, Turcato AM. Chapter in: Sandrini G, Homberg V, Saltuari L, Smania N, Pedrocchi A (eds), Advanced Technologies for the Rehabilitation of Gait and Balance Disorders (2018), 3-28.

2. “The Discovery Of Gravity & The People Who Discovered It”. Jennifer Spirko, Sciencing, Mar 2022: https://www.sciencing.com/discovery-gravity-people-discovered-16994/.

3. “Leonardo da Vinci’s Visualization of Gravity as a Form of Acceleration”, M Gharib, C Roh, F Noca. Leonardo (2023), 56(1): 21-27.

4. “Dialogue Concerning The Two Chief World Systems”, G Galilei (1637).

5. “Discourses and Mathematical Demonstrations Relating to Two New Sciences”, G Galilei. (1638): 72.

6. Apollo 15 Hammer-Feather Drop. NASA Solar System YouTube channel:

7. “Isaac Newton”. History.com editors (2015, updated 2025)

8. “How did Albert Einstein flunk math and still end up so smart?” From website: Science Questions with Surprising Answers, by Christopher S. Baird, PhD. Information drawn from Albert Einstein: A Biography by Albrecht Fölsing, 1997.

9. The Trouble With Gravity: Solving The Mystery Beneath Our Feet. R Panek; Houghton Mifflin Harcourt (New York), 2019.