Newton just won’t die.

First of all, God bless the man. Our mathematical approach to the universe produces all kinds of infinities and infinitesimals in our equations, and without his work, and the work of Leibniz, and I’m not getting into any discussion yet on who deserves the real credit for creating differential and integral calculus, we’d have been stopped dead scientifically for a really long time.

But his assumptions of a Platonic reference frame as a basis for all motion and concepts for mass and distance and inertia and gravity has stymied us all for more than three hundred years. That’s all broken.

Since the discovery of light’s nature as a wavefront people have been trying to get a grip on what the hell medium, what substance, light is a wavefront *in*, since you can’t have a wave without water. Sound is a wavefront we can detect in air (and other substances that are allowed to vibrate), for example. So when people thought of light as a wave, they tried hard to imagine — and to detect — the medium through which it travels. For a while they postulated *aether* as the substance. And that wasn’t a bad guess, all things considered.

Two hundred years after Newton left us all screwed up about inertia and gravity, Albert Michelson and Edward Morley set up a huge interferometer to try to detect Earth’s motion through the aether. It was sound in theory — create a wave source and as the boat moves into the wavefront, look for how it contracts or lengthens the distances between peaks and troughs depending on which direction you’re heading. It kind of screwed things up a bit when they couldn’t see any difference at all no matter which direction they looked. Lorentz swooped in to try to save them by offering them an equation to describe how the aether itself must be compressing in the direction of motion, but in the end, everyone had fits and just took a giant step backward, deciding it was the concept of aether itself that was the problem and that it was the Platonic framework of time and space itself that was compressing and stretching.

And for that, Einstein deserves his own dope-slap.

There’s only one word in the above that makes it horribly, horribly wrong, and that’s *framework*. Spacetime isn’t the graph paper that we draw everything on, they showed. And making it all rubbery really was just a step in the wrong direction, as frameworks go. Like you’d think. What good is a ruler that stretches and twists?

The aether answer was closer, frankly. If we equate spacetime and aether, conceptually, and leave out any possibility of an absolute Platonic framework, however stretchy, we’ve got a nearly workable solution. Spacetime is a substance, a measurable quantity with, you know, heft, and density, and distribution. A compressible fluid, gaseous, plasmid, viscous, sticky — with respect to actual void, at least.

It’s so hard for fish to talk about water. If you are a fish, and you’re in water, you can eventually figure it out. Water brings you currents and eddies of pressure and warmth. It offers resistance to movement and something to push against. It provides friction. Insulation. It provides some way to measure distance, by finstrokes at the very least. Pressure in it increases as you swim downward. It carries heat and sound and diffuses and refracts and reflects light. You can make it change phase and viscosity. And if you get a good run-up and jump, you can leave it behind.

Spacetime is a substance in which we are suspended and dissolved. We each carry our own with us, every separate one of us with our own viewpoints. It gives us what we take to be mass and energy and inertia and gravity. And the easiest way to know about spacetime is to leave it and look at its *absence*.

Everyone knows E = MC^{2}, but no one seems to look at it properly:

E_{j} = M_{kg} * C^{2}_{m2/s2}

All of the capital letters up there are just numbers. And there’s some simple algebra. All of the magic happens when you put in the units and look at what happens.

There’s an energy term out front, in joules for convenience, and it’s proportional (says the equation) to a measure of mass in kilograms multiplied by a somewhat more complicated term of spacetime in square meters per squared seconds. Hell, we don’t even know how to think about square seconds. But all of that is just algebra. You can solve that equation for any term — joules, kilograms, meters, seconds — and see that they are all introconvertible into one another.

It may help to know that the final term is in the same units that people who map the surface of the earth use to measure and map *geopotential* — a measure of the force of gravity. As you know, the measure of the acceleration force due to gravity changes depending on your depth in the gravity well, and changes additionally due to the distribution of the mass beneath you. Practically speaking.

But there you have it: energy and mass and gravity all existing only with respect to each other, only existing as an expression in terms of spacetime. But that’s not the only way of looking at things.

It worries some scientists that at the quantum scale that it’s really hard to detect anything like a gravitic force. For that matter, it’s hard to figure out which way the arrow of time points, too. Energy and particles are borrowed from the future and put back at whim as long as the numbers are small enough, borrowed from the foam of spacetime itself, expressed as “virtual particles” that can be made to do a little work before they disappear back into the water like leaping fish. Just about all of the transitions and transformations mapped by Feynman diagrams can happen in any direction. Space has different rules, too, with the usual idea of barriers not applying at all when particles change states via “tunneling”, popping from one allowed value to another without at all appearing in any excluded region where their existence would not be allowed.

We can see these virtual particles made permanent near black holes, where, when particles are produced in pairs, one of the two falls into the black hole and the other escapes. In a very similar way, time’s arrow appears on the quantum level, when it appears at all, due to the disturbance of a small amount of a large number of transitions, ordinarily reversible and actually reversing, under the influence of a not-entirely-uniform accelerating field — the same way a game of marbles would be a much different game if it took place on a playground slide. A debt can’t be paid back if the payment window keeps moving, accelerating away.

Does that make time a side-effect of an interfering non-uniform accelerating field, a translating force that *creates distance* between particles that were once close enough to revert to quantum foam, *creates split-seconds* between them so that they miss their appointments? Time, and space too. Spacetime is added to individual particles by translation of energy, by decay of mass, by imparting momentum. Distance in time and space is *created* by impact, *destroyed* by attraction — or, rather, translated into or out of mass or energy.

But all of that takes place in deep water. To actually get outside of the gravity/mass/energy-bound pressures of spacetime, you have to cancel the fields, create a special neutral arena where the chance of finding mass or energy or momentum or distance or differences in time is zero — or close enough to zero that Heisenberg is satisfied. A dimensionless condition of being where all kinds of things are permitted — except time and space and mass and energy and inertia. Perhaps a region where fields are excluded by a new kind of Faraday cage. Or a region cleared by cavitation, where the fabric of spacetime is stretched enough that it wears thin and tears.

This is the place that needs exploring — these holes between spaces, these dimensionless gaps outside of space and time — where new kinds of infinities and infinitesimals thrive, before the beginning and after the end, where everything is when it’s between moments. We must be like fish that are aware of water, that can experience air when we jump, that can imagine vacuum and what can exist within.

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