Gravity is a form of energy expressed whenever mass distorts space-time. Across the universe, gravity is expressed in rare instances for the reason that ordinary matter is uncommon, making up only around 5% of the universe’s particles.
Let’s say that you and I are made of superhero particles: we can create matter. Together, we decide to create a giant planet from nothingness, and then we hurl it into the recesses of space.
In the recesses of space, our newly created planet bends and warps space-time. As our giant marble settles into the fabric, gravity forms around our planet at the speed of light, and possibly at a rate greater than the speed of light (c).
Gravity is a powerful energy in this scenario. Where did that energy come from? You and I, as superheroes, created the planet, but we never created any gravity energy. And since the gravity was created at the speed of light, or faster, it’s impossible for the mass or thermal energy—both slower than c—of our new planet to have created the gravity at the speed of light.
So where did that gravity energy come from? That energy was already there, in space. When theoretical physicists use the word gravity, they are discussing what should more precisely be called the active form of gravity. There is also a passive form of gravity that we are not seeing or measuring but which is always there, in the darkness of space.
This passive form of gravity could be called dark energy. This dark energy is a pervasive force of our universe, filling space around us, resting quietly unless squeezed—activated—by mass.
Newton didn’t know what gravity was, but he observed the force, and described it mathematically. Einstein explained what caused gravity but his laws have difficulty describing its forces in all situations. Newton and Einstein were able to use human powers of observation and deduction to describe active gravity. Currently, we cannot use powers of observation to describe the opposite of active gravity: dark energy.
Why? To answer this, we have to turn to quantum mechanics, which predicts gravitons, small particles that create gravity. These gravitons produce both active gravity and dark energy. This seems like a paradox, but M-theory mathematically predicts eleven dimensions, and if these gravitons are closed strings, the idea is that they can gravitate between dimensions quite readily. Some of those dimensions are outside the powers of human observation.
Let’s connect the dots. Gravitons are small strings, with a special property among their peers: the ability to float between dimensions at a rate of c, or greater. Gravitons undisturbed by matter can be considered gravitons at rest; these exist in a dimension where humans cannot feel the gravity. In this state, they occupy space in the form of dark energy. Gravitons which are disturbed by matter can be considered active, and in their active state, they exist in a dimension whereby they produce a force we feel as gravity.
To further complete the picture, the disappearing-reappearing paired particles that quantum mechanics predicts in space are likely also gravitons. Gravitons are strings and therefore do have some mass. Therefore, in microscopic bits of time one partner can activate the other partner, such that one graviton string is dark energy and the other graviton string is active gravity. The key here is that this would only happen for infinitesimally small periods of time because a graviton string doesn’t carry enough mass for any long period of space-time distortion. Yet, taken together, all the isolated gravitons in the universe flitting into activity would be a substantial force. Out in space, this force would be too micro for a human to feel at any one point, but collectively over regions of space, large enough to affect the observable physics of the universe.
The big shift in thinking here is understanding gravity at rest. Picture that, and the rest becomes easy. The amazing part is that our benelles are a self-aware expression of this harmonic elegance.