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52% off (Sale price $60.00, Reg. Price $125.00) :: Choose Between Two Options $60 for one month of tumbling, flight-school, or basic cheerleading classes ($125 value) $110 for two months of tumbling, flight-school, or basic cheerleading classes ($250 value)pGravity: From Apples to PlanetsThough they sometimes seem to defy it, cheerleaders and tumblers always come back to the ground due to the pull of gravity. Read on to learn why this force isn’t as simple as bouncing up and falling down.Except for amnesiac astronauts and cartoon characters who haven’t looked down yet, everyone knows that gravity works. But when it comes to how and why, gravity fits a little uneasily into physical explanations of our universe. Perhaps the most important explanation comes from Albert Einstein. According to his general theory of relativity, anything that has mass warps space-time, causing a “dimple” that, if the mass is big enough, draws other objects into its orbit. (Consider how a child sitting on a trampoline warps the fabric; now imagine that that fabric is not a surface but a four-dimensional field surrounding the child on all sides.) Einstein’s theory predicts the behavior of our universe’s bodies with great accuracy. It is even largely compatible with later developments in quantum mechanics, the laws of which account for forces on the subatomic scale: you simply need to posit the existence of the graviton, a theoretical particle that is the “substance” of gravity in the same way that photons are the stuff of electromagnetism. This convenient construction does, however, break down at distances smaller than the ultra-tiny unit known as the Planck length. Some have theorized that this may because quantum effects take over entirely at that scale, others that it’s because space-time itself is actually discrete: if distances smaller than the Planck length do not exist, it is nonsensical to consider how gravity works within them. This minute realm is one of physics’ major frontiers, which can only be settled with the help of gravity.Things seemed much simpler in Isaac Newton’s d
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