Blog

Gravity

By February 9, 2020 No Comments

Gravity is a mysterious force we had all wrong for hundreds of years.  This quintessential force, ever in our face as a bastion of defiance to human understanding, is ubiquitous throughout the universe.  Can you, right now where you sit, explain how it works?  Even if you can recite the formula for it (hint: It isn’t Newton’s inverse square law) can you explain why it works?  Two bodies will always attract each other no matter their size or distance and the more massive an object, the stronger it’s pull.  People on the opposite side of the world aren’t actually upside down because of gravity, and the tides, rain, waterfalls, and relaxing in your favorite chair are all courtesy of gravity.  And to me, gravity always feels strongest in my favorite chair!

There are actually four fundamental forces we experience, including gravity, the electromagnetic force, and the strong and weak nuclear forces.  Though equally important, they are different in important ways like superheroes possessing diverse powers.  Gravity is the weakest of the four and has no limit to its reach, like the still small voice of God throughout the universe.  Gravity’s reach is infinite.  It exists between everything and everyone and there is no escape from it – it’s always there.  I know, I know, what about the astronauts on the space station floating in zero gravity?  In low earth orbit, those astronauts still aren’t free from earth’s gravitational pull; rather, they’re in continual free fall similar to when an airplane drops suddenly in turbulence and you come up out of your seat.  If you fly away from earth and keep on going into space, you would never escape the force of earth’s pull, not even after the millionth mile.  You can’t outrun gravity and you can’t block it or shield yourself from it.  While you can climb into a metal box to escape radio waves and electromagnetic forces, gravity can’t be evaded.  It truly is a means of God holding all things together by the word of His power.  Gravity also reflects God’s faithfulness and consistency as seen in the tides and rising of the sun every morning.  The tidal force is actually a differential force exerted on the earth because the moon is farther away from one side of the earth than the other.  The strength of gravity is inversely proportional to the square of the distance from one object to another and there is an 8,000-mile difference between the near and far sides of the earth from the moon.  That gravity gradient pulls on the earth causing a squeezing back and forth, and the water rises and ebbs in response as if sloshing side to side in a bucket.  Published times of high and low tides are just as reliable as our tables of sunrises and sunsets, which of course reflect the orbit of the earth around the sun and the slowly changing effect of our axial tilt as our position changes throughout the year.  This is all owed to the gravitational stability of our solar system in which the earth, moon, and sun move at incredible velocities.

But exactly what is gravity?  Einstein theorized it was curvature in spacetime in the presence of mass.  You fall into the earth because the earth has curved spacetime the way a mattress deforms when you place a bowling ball in the middle of it.  Objects roll toward the ball on the mattress because they achieve a lower energy state there.  In this view, gravity is a consequence, not a force.  Mass is intrinsic and gravity a resultant observation.

What does this reveal about God’s nature?  The Holy Spirit is omnipresent and His influence is infinite throughout the heavens.  Gravity is reliable and consistent.  I also think gravity reflects the perspicuity of Scripture.  You see, everything a person needs to know about salvation and the Gospel may be clearly understood from the Bible, but the Bible is also sophisticated and rich with deep insights waiting to be mined.  This truth is called the doctrine of perspicuity and, similarly, gravity is plainly understood by everyone as a continual and ever-present force holding their feet to the ground, yet scientific study continues to look deeper into the phenomenon now best mathematically described with differential field equations and tensors.  Job 26:7 tells us that God hangs the earth on nothing.  Gravity both demonstrates God’s power in creation and His faithfulness in holding all things together.  Like Him, it is understood immediately but defies perfect understanding.  In Psalm 139:7, the psalmist asks the LORD, rhetorically, where can I flee from your presence? and the physicist could write the same about gravity.