Thanks to Isaac Newton and other insightful thinkers, science has developed two general ways of viewing “reality.” One deals with big things we can see around us. Newton, Kepler and others used mathematics to predict the interactions of these “macro-objects.” These ideas, reduced to mathematical formulas, explain why planets revolve around the sun, why we fall down instead of up, and developed an understanding of natural forces. These “laws” and the scientific application of them are so accurate the New Horizons spacecraft made it to the planet Pluto after a trip of nine and a half years, arriving precisely where the formulas said it would. Essentially, everything that happens on Earth does so according to these “Classical” laws. Since the time of Newton, scientists were convinced they had all the basics figured out.
But then along came Albert Einstein and said wait a minute. Newton’s laws are close, but not perfect. Newton’s laws didn’t quite match certain observations including the orbit of Mercury around the sun. Einstein’s famous Theory of Relativity corrected that error. But an odd discovery sprang from Einstein’s equations so bizarre even he could not accept it.
Welcome to the quantum world. At the level of the very small atomic quantum scale, Nature appears to have created an entirely different set of rules. The rules that govern the world of the big (our world) do not work at the level of the very small, and the rules that work at the very small don’t work at the macro-level. For instance, if the rules at the quantum scale worked at our level, we could be in two places at the same time. Our existence would not be based on anything tangible or solid, but rather a set of probabilities and bits of almost nothing and tiny immortal particles that have no mass whatsoever.
Shouldn’t there be one set of rules that work at every level? After all, we and everything around us are made up of the tiny particles of the sub-atomic world. Scientists have no definitive answer, and many have been actively searching for a way (tentatively called the Grand Unification Theory) to link the two for nearly the last hundred years.
So we have accurate ways to measure, observe and predict what happens at the tiniest atomic levels and also at our level. These methods don’t agree with each other but they work in their own domain. But there is also a third level that is lumped in with us that perhaps shouldn’t be. That is when the size of things reach that of galaxies and then groups of galaxies and billions of galaxies that band together to form incomprehensibly long “strings.” If we could view this vastness from the outside, the visible Universe would look like a vast web with these strings of galaxies and vast voids where nothing at all exists.
And here’s the thing. The rules that govern motion at our level do not work at the galactic level either. The most common picture of a galaxy is something that looks like a pinwheel with arms of stars radiating out from the center. Our own galaxy probably looks like that. (Hard to be absolutely sure about that because we are inside looking out, but evidence supports this view.) If the Classical laws we are used to on Earth are applied to the galaxy, it would fly apart. For stars, the farther planets are from them, the slower they move. This is a hard and fast rule. But at the level of a galaxy, the farther out an object is from the center, the faster it moves. The galaxy should fly apart but it doesn’t. There are some ideas but no one knows why. Currently, this apparent contradiction is explained by the presence of “dark matter,” a mysterious invisible substance that exerts the force necessary to speed up the rotation of objects away from the galactic center and hold it all together. Several ingenious experiments are underway to find this elusive material, yet none have succeeded. Dark matter may in fact exist, but it might also be more akin to what is sometimes referred to as the “fudge factor,” a quantity thrown into the mix to make theory match observation until the actual explanation can be determined. But it all adds up to the realization that the true nature of reality remains a tantalizing mystery.
Email Terry Mejdrich at email@example.com.