And so I find myself this happy Monday, buried in grading and unable to stop thinking about the fundamentals of physics - both at particulate and astronomical scales.
We know the universe is expanding. And that it is doing so at an accelerating rate. But what is it expanding into?
We know that gravity, the attractive force between massive objects ought to counter that expansion, sooner or later, but it seems there is some other force at work here. Some kind of "dark energy" that provides a repulsive force, propelling the universe ever outward into... what?
I am reminded of the theoretical model of the tides. In this model, the Earth and its watery envelope bulges on the side nearest to the moon due to gravitational attraction. On the other side, the Earth and the oceans bulge, but for a different reason - rotational inertia, which is sometimes described as centrifugal force. Could it be that the universe has such a spin that propels it ever outward?
Others have questioned along these lines. The apparent answer does not satisfy: if we measure from different points, we should see different things based on if the universe is spinning or not or how much. This is where my ignorance of the subject becomes a liability and eggs me on to learn more.
But for now, another question: is it possible that the scale of our vantage points just isn't big enough to resolve the spin, its direction or momentum?
As for what it is expanding into, I am reminded of ripples. A minor disturbance to the surface of a calm pool of water causes the energy to propagate outward, endlessly - well, at least to the edges of the pond. Why?
This reminds me of a conversation I recently had with a student. He envisioned this outward expansion as being limited by a tenuous connection between all particles. When everything had unraveled so completely as to only be attached in a linear way, only then would the universe begin to collapse back in on itself. An interesting notion, one worth exploring.
His description led me to envision a spherical or perhaps even toroidal universe. If the ripple model applies to an expanding universe, toroidal is the way to go. But still the question remains: what does it expand into, in an apparently edgeless, infinite 'verse?
It staggers. And leaves me with an unquenchable thirst.
Another puzzle: the double-slit experiment. I need to better understand this test - the ways its been performed, the hypotheses tested, the conclusions. I feel like I'm missing something about the resultant interference pattern.
Something tells me it has to do with energy levels.
When you blow into a penny whistle, it emits a particular pitch determined by the length of the whistle. BUT, if you blow a little harder, it emits at a much higher pitch. It is possible, if you blow just the right amount of air, that it will emit both pitches at the same time. What does this have to do with wave-particle duality? I'm not sure, but I want the math to explore it more.
So for the first time, in I don't know how many years, I am setting a New Year's Resolution. I will start here, with Tibee's playlist. From there, who knows. But there must be a way to sate this thirst.
Onward! Outward! upward! Through! Ganapati Om Jaya
