If you accelerate an object to the left, it will resist your attempt to accelerate it. By resisting your attempt to accelerate it, a force is produced against the accelerating force. This force against the accelerating force is equal in magnitude to the accelerating force and opposite in direction to the accelerating force.
If you accelerate the same object to the right, the same effect occurs, a force is produced equal in magnitude but opposite in direction to the accelerating force. The same thing happens if you try to accelerate the object forward or backwards.
This force that is equal in magnitude and opposition in direction to the accelerating force is produced by the object's mass resisting acceleration (its inertia).
Since the object's mass resists acceleration forward or backward, or left or right, then theoretically, it should also resist acceleration downward.
Since gravity is a downward accelerating force, this means that the object would produce a force equal in magnitude but opposite in direction to the downward accelerating force, the same way it produced a force equal in magnitude but opposite in direction to the leftward accelerating force, rightward accelerating force, forward accelerating force, or backward accelerating force.
Since the downward accelerating force is gravity, this means therefore that the object is producing a force equal in magnitude but opposite in direction to the force of gravity.
Is there such a force, produced by an object's inertia, equal in magnitude but opposite in direction to the force of gravity?