Two things - God & Potential
POTENTIAL
Secondly, I have always errored to the side of the weak anthropic principle over the strong. Over the years I have discussed WAP v SAP many times. Here are few references which may be followed up here and here and here and here. My apologies on this last link but somewhere in my earlier "indeterminancy" posts lies a more embedded discussion; if someone locates it please post in the comments below. Thx).
Two observations
Weak Anthropic Principle (WAP) - If the universe was not able to produce us, we wouldn't be here and we wouldn't know it existed.
Strong Anthropic Principle (SAP) - The universe exists the way it is for our benefit. Observers are the point of the universe. No us, no universe.
Summary - I prefer to think of them as the reasonable and the egotistical versions of the Anthropic principle. Basically the weak version is a common sense statement and the strong is baseless speculation. - Google Anon
...Those are the weak/strong versions of Tipler and company-- the more standard original distinction by Carter (I got most of this from Wiki) is simply that the Weak AP says that "given the fundamental parameters we observe, we have to live in a place and time that is conducive to life." Thus the WAP is only relevant to resolving "fine tuning" problems in regard to why we are here now, as opposed to somewhere else later. Given the cosmological principle that all places are more or less the same, the "fine tuning" that is resolved is purely temporal-- why we are here after 13.7 billion years and not 1 year or 1 decillion years.The Strong AP goes on to look at the fundamental physical parameters themselves, and asserts that they also have to be fine tuned such that we (human being) could come along at some point in space and time. So it talks about why if you monkey even just a little with the dimensionless ratios of the universe, you seem to dramatically alter the resulting likelihood for generating life. [ <-- process theology does not take this line of thought; it states that regardless of how you tinker, the results will always produce cosmic "life" in other ways. So, not one way to life, but an infinite array or life-creating paths. - re slater]The reason the SAP is more speculative is that it is not clear what you are comparing-- you can compare life as it might develop in different places and times, and might scientifically find evidence for such life, but life in other hypothetical universes would seem to be a nonscientific issue. So the SAP is not really considered testable science, it's more philosophy, whereas the WAP is on a more solid footing in regard to the general requirements of a scientific explanation.Personally, I don't think the SAP gives us any understanding of why the parameters are what they are, beyond the obvious point that given the laws we have found, the parameters would have to be within certain ranges or we couldn't be here. That doesn't qualify as "understanding" in my book. The idea that this does not require "fine tuning" on the grounds that there can be many other universes with other parameters that are not fine tuned, but we had to show up here, seems a fruitless and untestable claim. For example, how would one attribute a "probability" to a "universe"? Should we allow the laws to be anything [more or less] in these hypothetical universes, or assert the laws have to be the same only with different parameters?
Physically speaking, our Universe seems uncannily perfect. It stands to reason that if it wasn't, life as we know it – and planets, atoms, everything else really – wouldn't exist.
Now, three physicists from the US, France, and Korea have put forward a new explanation for why life, the Universe, and everything in it has had such a prime opportunity to exist at all.
For some reason, the amount of energy – or more precisely, the mass it equates – and the Universe's accelerating expansion are so neatly balanced, there's been ample opportunity for a few interesting things to unfold over the past 13 billion years or so.
A few magnitudes either way, and the overwhelming gravity would have glued the expansion of spacetime together better than a mouthful of taffy... or been so weak, the rapidly expanding Universe would have left little of interest in its wake.
Such an apparent near-perfect balance might be a consequence of something called fine-tuning, a process in physics where the features of a system necessarily match or cancel out with such precision. If it didn't, the system just wouldn't look the way it does.
For example, our Universe happens to be neutrally charged. For some reason, there happens to be a near-identical number of protons to cancel out each electron's charge; add a few more electrons and it would be negative, forcing clumps of matter to push itself apart.
On the other hand, it could be a consequence of what's referred to as 'naturalness'. The Moon's near-perfect occlusion of the Sun during a solar eclipse, for example, isn't ordained by hard laws of astronomy. The size of the Moon, the Sun, and our perspective of both don't need any further explanations to make sense.
Physicists generally don't like appealing to vague coincidences when they observe the Universe. If two features of a system seem incredibly well matched, there's a strong desire to dig through the rulebook for a deeper explanation.
For electrons and protons, the solution could come with explanations of why there's an imbalance of matter over antimatter.
In the case of the Universe's incredible reflection of energy and expansion, there's no shortage of clever and creative ideas to chew on. Most tend to fall into two categories, however.
One centers on something called the anthropic principle, which says only a universe capable of generating thinking brains like ours can ask philosophical questions such as 'why am I here?'
This might imply there are other universes, though. Maybe an infinite number, most either collapsing the moment they're born or exploding in puffs of endless boredom. Ours just happens to be one of the good ones! Although fun to think about, without any way of establishing the existence of multiverses it isn't a proposition that could bear scientific fruit.
As for the second category, there is the possibility that we're missing some crucial piece of the physics puzzle, such as new fields or symmetries that could fail under specific conditions.
The fact that the resting mass of the Higgs boson – the particle representing a field that gives many fundamental particles their mass – turned out to be unexpectedly light might suggest there's a gap in our understanding of forces and particles.
It itself is the result of another fine-tuning conundrum, being the result of strangely-exact cancellations of other physics. For example, there seems to be some sort of mysterious fine-tuning between the mass of a Higgs boson and the cosmological constant – the density of energy in the vacuum of space.
This latest suggestion mashes together the idea of unknown physics behind the Higgs boson's shockingly itty-bitty mass with a kind of quantum multiverse effect, one that this time could feasibly be tested.
Their model puts the Higgs particle at the center of the fine-tuning explanation. By coupling the boson with other particles in such a way that its low mass would effectively 'trigger' events in physics we observe, it provides a link between forces and mass.
From there, the authors show how weakly interacting variables in a field might affect different kinds of empty space, specifically patches of nothingness with varying degrees of expansion. This potentially demonstrates the link between Higgs bosons and the cosmological constant.
It's a multiverse in a way, given the triggers occurring in different patches of infinite expanding space could plausibly give rise to a seemingly well balanced Universe like ours.
Their math suggests these triggers would be limited to a few possibilities, and even has room for explanations of dark matter. Better still, it also predicts the existence of multiple Higgs particles of varying masses, all smaller than the one we've already observed. That gives the hypothesis something that can be tested, at least.
Until then, it'll remain one of many neat ideas that could one day explain the eerily well-matched tug-of-war that has permitted a complex cosmos to unfold. A place we've come to love as our Universe.
This research was published in Physical Review D.
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