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Scientists Find That Conditions For Life May Hinge On How Fast the Universe Is Expanding (sciencemag.org)
sciencehabit writes: Scientists have known for several years now that stars, galaxies, and almost everything in the universe is moving away from us (and from everything else) at a faster and faster pace. Now, it turns out that the unknown forces behind the rate of this accelerating expansion - a mathematical value called the cosmological constant - may play a previously unexplored role in creating the right conditions for life. That is the conclusion that a group of physicists who studied the effects of massive cosmic explosions, called gamma ray bursts, on planets made. They found that when it comes to growing life, it's better to be far away from your neighbors - and the cosmological constant helps thin out the neighborhood.
I feel like my quality of life goes up the further I live from my neighbors.
"when it comes to growing life, it's better to be far away from your neighbors -" . ... Not only that but I found its easier to create life if you are far away from your in-laws.
so...does that mean the expanding universe provides more chances for more life?
Or, there could be "zillions" of universes all with different laws of physics. The vast majority are probably "duds" in terms of complex life. We are not "lucky" in the usual sense, but only in the sense that ponderers of existence will only exist in universes that allow ponderers to form. There are no existence-ponderers in the dud universes (by definition of "dud" here). I'd call that a form of feedback-based perspective, not luck.
Or, maybe there's something weird going on with quantum physics-like probabilities in terms of observers influencing things; guiding or pruning them in a way. Okay, time to put down Sheldon's bong...
Table-ized A.I.
Unless you're really close to a gamma ray burst, your planet will not be radiation-sterilized. And since most life is in the oceans and underground, it will not notice when the ozone layer is burned off. Anyway, the effect would be temporary. I have a feeling that this is a case of physicists who don't understand the difference between the resilience of familiar lifeforms and the resilience of life.
TFS mentions a "cosmological constant" as the reason for the acceleration of the expansion of the universe. I thought that the cosmological constant was a so-called "fudge factor" to back the steady state theory-- and that Einstein said it was the biggest blunder of his career. Can someone enlighten me about which constant is being referred to in the summary?
"No man's life, liberty, or property are safe while the legislature is in session." -- Judge Gideon J. Tucker
You raise a worthy query.
But I'd like to raise a couple of concerns. First, you could just have done a quick websearch on "Cosmological Constant". The Wikipedia article alone is enough to answer your query although the math there might turn some away. Second, though, and much more concerning to me is this strange apparent deification of Einstein. The man was a decent scientist. But he was surrounded by and worked with many other incredibly talented folk. On many things he was correct. However, he was on the wrong side of many debates. One of the cool things about Einstein was that he was able to admit when he was wrong (though it may have taken a bit of time and patience for folk to demonstrate where and why he was wrong).
But the Cosmological Constant? Nah. That one is easy. He added it, as you've described as much because of what he wanted to be true rather than what evidence had shown to be true. But when he did so, the evidence wasn't so strong either way. Pretty much as soon as the evidence rolled in, he backed off.
So why is it back in play now? Well, you need to understand it's been back for years now. This aspect isn't new. The authors of this article don't need to defend it. Indeed, nobody really does. Why? Because more evidence keeps rolling in and now we know we need it. Evidence trumps theories.
But this isn't a binary thing. It's not off/on. It, at the very least, is negative/zero/positive. Einstein set it to a negative value. He'd hoped this resulted in a static universe. Now we know that even that isn't correct. It's static, but unstable. When removing it, he essentially set it to zero. This matched an expanding universe. But as the evidence kept rolling in, it's clear that the universe isn't just expanding - it's expanding at an ever increasing rate. To get that, you need a positive value.
There is a SciFi book about this, Calculating God. The plot device is that aliens have discovered that this is indeed testable, and there could not have been anywhere near enough "buds." (That said, the god they find is not most religions' idea of God.)
I think, in the background of this article and others like it hovers the assumption that life is a rare, unlikely event. I would argue that the opposite is the case: life is something that must arise in any dynamic system, unless there are specific conditions against it. Since the Miller-Urey experiment in the 50es we have seen a growing body of evidence suggesting that the components of life are generated all the time, everywhere, cosmologically speaking, and that life itself is simply another level of chemical complexity, to put it simply.
I said 'dynamic system' for a reason: dynamic systems are mathematical abstractions of the physical world, and even on that level you can begin to see glimpses of something central for life: spotaneous, localised decreases in entropy. Drawing lines from there to life itself is of course wildly speculative, but I am very much in favour of the idea that the universe is teeming with life; read Stephen Baxter's "exultant (sic)" for some interesting thoughts about this idea (as well as some good SF).