My god, it’s full of stars…wait, no-

Wednesday, January 19th, 2011 @ 3:42 am | Science

For a good primer on dark energy and how Einstein saw the signs but lost faith in himself, this is a must read.

If the dark energy doesn’t degrade over time, then the accelerated expansion of space will continue unabated, dragging away distant galaxies ever farther and ever faster. A hundred billion years from now, any galaxy that’s not resident in our neighborhood will have been swept away by swelling space for so long that it will be racing from us at faster than the speed of light. (Although nothing can move through space faster than the speed of light, there’s no limit on how fast space itself can expand.)

Light emitted by such galaxies will therefore fight a losing battle to traverse the rapidly widening gulf that separates us. The light will never reach Earth and so the galaxies will slip permanently beyond our capacity to see, regardless of how powerful our telescopes may become.

Because of this, when future astronomers look to the sky, they will no longer witness the past. The past will have drifted beyond the cliffs of space. Observations will reveal nothing but an endless stretch of inky black stillness.

This kind of stuff is like liquid crack to me…

-hw

2 Responses to “My god, it’s full of stars…wait, no-”

  1. AJKamper Says:

    In a parallel life I grew up to be an astrophysicist. I’m addicted to this material. My fellow law students look over at my screen and see I’m reading the latest stuff on cosmology.

    I actually have a complaint with the article, though, because it implies that there was something inherent in general relativity that required dark energy, but he decided he messed up. In reality, it’s more like he wanted a number to multiply forces by in order to get the result he wanted, so he fudged without a lick of rational evidence for so doing. The only way he was “right” about the cosmological constant is that he created a theory powerful enough to contain it… or dark energy more generally.

    But putting a mention of Einstein in your columns helps readership significantly.

    I’d also say that we’re pretty accustomed to having horizons that we can’t peer behind as well. Take, for example, the Big Bang. There might be a plethora of truths behind that which we simply can not see–though some physicists are working at finding predictable consequences from What Happened Before.

    Good book I just read on this is From Eternity to Here, by Sean Carroll. Though I had to read it twice before I REALLY understood it, and I’m pretty well-versed for a layman.

  2. Henry Whistler Says:

    As I’m fond of saying, we pull aside curtains to find more curtains…