Mark Megahan
Does anybody really know what time it is? The old song asks. Does anybody really care? Astrophysicists can definitively say “no” on the first one and you bet they care. They care because it takes the prevailing theory and throws it in the trash. When they went back to the drawing board they didn’t have to start with a blank sheet of paper. They have a new idea already sketched up.
Time and expansion of space
If the new time model is correct, you can forget everything you’ve been told about “dark” matter and energy. That’s okay because scientists have been uncomfortable with those “fudge factor” concepts since they were first introduced. The problem is massive.
“There doesn’t seem to be enough mass to account for the gravitational effects we observe, so we invented an invisible placeholder called dark matter.” That’s only half of it.
Our observations indicate that not only is our universe expanding, the expansion is accelerating. Since that appears to defy gravity, experts postulated a “dark energy” force.
Perhaps, researchers pondered, the expansion we see is only an illusion? The “Timescape” cosmology would explain that. It’s already been proven that time is not the same from one place to another.
When people think of an expanding universe, they think of a toy balloon being inflated. Instead of a uniform distribution inside, as the air in a balloon, the universe is more like lumpy mashed potatoes. Filled with Swiss Cheese “time bubbles.”
Nothing, it seems, makes all the difference. Nothing moves faster than nothing. That means everywhere there’s something, it ages slower. Most of space really is nothing but space but nobody’s been taking that into consideration.
Matter means gravity
Matter, we’ve all been taught since kindergarten creates gravity. The more matter, the stronger the gravity. We’re stuck to a big lump of rock called the Earth which is stuck to a star which is held by a galaxy.
At the center of just about every galaxy is at least one black hole. The older a black hole gets, the more massive it becomes. That folds gravity around it in tighter and tighter spirals. Space and Time get folded around with it.
Meanwhile, between galaxies are huge voids of theoretically absolute nothingness. “An atomic clock located in a galaxy could tick up to a third slower than the same clock in the middle of a void.” That makes a huge difference over the lifespan of our universe.
The time discrepancies can explain the observations. “When you stretch that over the huge lifespan of the Universe, billions more years may have passed in the voids than in the matter-dense areas.”
Astrophysicists are shocked to realize “that it no longer makes sense to say that the Universe has a single unified age of 13.8 billion years. Instead, different regions would have different ages.”
If you “look at an object on the far side of a void, it would appear to be moving away from you much faster than something on this side of the void. Over time, these voids take up a larger proportion of the Universe, creating the illusion of an accelerating expansion, without needing to conjure up any dark energy.“
