Okay... So, this one might be a bit esoteric.
I was reading an article in Discover today about Mordehai Milgrom's Modified Newtonian Dynamics theory or MOND, as it is referred to. Mr. Milgrom's theory is controversial. Why is that, you say? Because he went and mucked with the cornerstone of Physics, Isaac Newton's equation "F=ma." If you are not familiar with that equation, what it says is that Force = mass X acceleration. For example, if you take a mass (like the human body) and accelerate it (say, in a car) a force will be exerted upon it (which you feel as you're being pushed back into the seat). For centuries, it's been used to calculate everything from rocket trajectories, to planetary orbits, to the weight of the sun. Mr. Milgrom saw fit to go and fuck with all that... Here's why.
Back in the 70's, between snorting piles of coke and popping in different Donna Summer 8 tracks, scientists were measuring the rotation of galaxies. A galaxy does not all rotate at the same speed. The stuff on the inside rotates faster than the stuff on the outside. It's like when an ice skater pulls her arms in while she's spinning and she rotates faster. Now imagine if her hands were somehow instantaneously severed from her arms. When she pulled her arms in, the non-severed parts of her would rotate faster, but her hands would continue to rotate at the same speed. The longer her arms were in the first place, the slower her hands would be rotating relative to the rest of her.
The reason this is important is that you can back your way into figuring out the total mass of a galaxy if you can document the rotational speed as you work your way out from the center of the galaxy. But, there was a problem...
As the scientists worked their way out from the center, they noticed that there was a point where the stuff toward the outside of a galaxy was spinning faster than it should, given Newton's equation - they call this "flattening of the rotation curve." What this seemed to indicate is that the gravity from the center of the galaxy was having more of an effect than it should on the stuff towards the outer edge of the galaxy. This kind of messed their shit up.
So, they needed a way to explain this. What those coke-addled disco scientists did was invent the concept of dark matter. Dark matter has always bugged me because it seems like the cosmological version of a homunculus. Basically, what they're saying is, "Uhhh... I dunno. Something must be there that we can't see. That's what's creating the extra gravity." In order for this to work, something like 20% of our universe would need to be composed of "dark matter." For 30-some years, they've been trying to detect dark matter with no success.
What Milgrom did was fiddle with Newton's equation. The idea being that, just maybe, there was just a little more to the equation than that. What he proposed was F = ma2/a0, but only if the acceleration were low enough - on the order of a 10 billionth of a meter per second per second. That's pretty freakin' slow. Thing is, it worked like a charm. The only problem is that it doesn't really offer an explanation why.
Here's what I'm proposing:
Gravity is pretty freakin' weak. How weak, you say? Let's put it like this: We are held fast to Terra Firma because of the gravity field of the Earth, which weighs 13.17 septillion pounds. Even so, a reasonably athletic man who weighs 200 pounds can propel himself 2-3 feet off the ground with little effort before gravity catches up with him and pulls him back down again. So, it's hard to imagine a force weaker than gravity. But, what if there was?
What if space-time itself had some sort of plasticity? What if it (to some very small degree) didn't want to submit to gravity? What if, when the gravitational force becomes small enough, matter would simply drag space-time along with it?
Imagine soap bubbles. It doesn't take much force to make them pop. But, a force small enough (say, blowing on it) will move the bubble as a whole. Or imagine a liquid. Stirring violently will create eddies while a slow stir will get the whole pot rotating along with the spoon.
What if space-time is viscous at a degree to which gravity is strong enough to cause eddies, but lessen that gravitational force enough and you can stir space-time - say 10 billionths of a meter per second per second? I need a person much smarter than myself to tell me why this wouldn't work.
Thanks for listening to my harebrained idea.
technorati tags:cosmology, MOND, physics, gravity