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The fabric of spacetime is roiling with vibrating quantum fields, known as the vacuum energy. It\u2019s right there, everywhere we look. Could we ever get anything out of it?<\/p>\n
<\/p>\n We can even calculate the strength of this vacuum energy. When we apply the rules of quantum mechanics to determine how much the fields vibrate in isolation, we get\u2026infinity. That\u2019s right, there\u2019s an infinite amount of energy filling every bit of spacetime. That\u2019s because there\u2019s no limit to the amount of vibrations that these fields can have. Small vibrations, medium vibrations, and big vibrations are all happening in every quantum field simultaneously.<\/p>\n Wait, wait\u2026how can the fields have infinite energy but still have more<\/em> energy to produce particles? To answer this question we can turn to a clever experiment designed by the Dutch physicist Hendrik Casimir.<\/p>\n If you take two metal plates and stick them really, really close together, the quantum fields between those plates must behave in a certain way. The wavelengths of their vibrations must fit perfectly between the plates, just like the vibrations on a guitar string have to fit their wavelengths to the length of the string. In the quantum case, there are still an infinite number of vibrations between the plates, but there are not as many infinite vibrations between the plates as there are outside the plates.<\/p>\n Using some clever bits of mathematics, we can subtract the two kinds of infinities and arrive at a finite number. This means that there really are more quantum vibrations outside the two plates than there are inside the place. This leads to the conclusion that the quantum fields outside the plates push the two plates together, something called the Casimir effect. We can measure this effect and verify that the quantum fields actually do exist.<\/p>\n All this theory and experiment results in a startling conclusion. All the physics of the world, every interaction, every process, and action, takes place on a stage filled with an infinite amount of vacuum energy. As weird as this picture is, it\u2019s the result of decades of investigation into quantum theory.<\/p>\n \n