The Meaning of Time

Periodically, every so often, interesting discussions or ideas really blow my mind, make me sit up and wonder... It happened in class Tuesday night: The notion of a variable rate to the Big Bang had never occurred to me, I had not heard it before. The wind just raced through my mind! That theories of physics are mostly "time reversible" was a virtual gale force. Actually, as I think of it, the notion that any video of molecules in motion would look the same run forward or backward only reinforces the feeling I have often had that "in reality" there is only the NOW.

If we begin with the idea of the Big Bang, then Time would only be a measure of Space. Space is what gets "expanded" as the initial infinitely small, infinitely dense "stuff" explodes. How far the "stuff" has traveled is determined by how much Time has passed. (Vice versa as well, I suppose.) All is One except as Time (Space) has separated us. Again, "in reality" there is only Space and the NOW; our usual, common sense of Time is only a mental construct useful in the function of our society. But again it is common sense to see Time as a measure of Space as in "I will be there in fifteen minutes."

It is also written that the original "stuff" was very hot with energy distributed uniformly and that as the Universe grows its temperature drops, leaving less energy to perform work in the future. Entropy, disorder, increases. The dictionary defines entropy as "a measure of the amount of energy unavailable for work in a thermodynamic system... a closed system, as the universe." Is the key word in the definition "unavailable?" If "unavailable" does that mean "not there" or just there and not available for work? With a different kind of technology could we harness the disorder and use its energy, which is currently defined as unavailable, to "restore" order? Would this technology make the Universe run in reverse? Or would this only reflect that video of molecules which appears the same run forward and backward?

I understand Einstein's curving space idea to explain gravitation attraction through a vacuum, as in the planets around the Sun. But representations of curved space I have seen are always two-dimensional "much like a stretched sheet of elastic material would accommodate itself to a heavy ball placed on its center area." So how does one represent curvature of space in three dimensions?

The discussion of a clock heading into a black hole and its apparent contradictions in appearance depending on the location of the viewer is also interesting. To an outside observer the clock's signals slow as the clock approaches the event horizon until, "past" the event horizon, its signals stop altogether. To an observer traveling with the clock, there is no slowing of signals approaching the event horizon. Although this discussion is an interesting way to understand some of the characteristics of a black hole, again, I think, the kind of Time measured by a clock is only a mental construct, there is only NOW.

"What if...?" Seems to me the Universe has to be either one of two things, either it is infinite and by definition includes every possibility and variation; or it is finite, and does not. If finite, then what is "outside" of it? Can anything which is conceived even be outside of it? And what does its boundary look like? If, on the other hand, it is infinite, well then, SURPRISE! Somewhere, our planet never had a moon, the dinosaurs never became extinct, Rome never fell, the Muslims conquered Europe, Germany won WW II, et cetera, et cetera, et cetera.

I certainly do not understand all of this, but I love it.