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Where Do the Laws of Nature Come From?
mlimber writes "The NYTimes science section has up an interesting article discussing the nature of scientific laws. It comes partly in reply to physicist Paul Davies, whose recent op-ed in same paper lit up the blogosphere and solicited flurry of reader responses to the editorial page. It asks, 'Are [laws of nature] merely fancy bookkeeping, a way of organizing facts about the world? Do they govern nature or just describe it? And does it matter that we don't know and that most scientists don't seem to know or care where they come from?' The current article proceeds to survey different views on the matter. The author seems to be poking fun at himself by quoting Richard Feynman's epigram, 'Philosophy of science is about as useful to scientists as ornithology is to birds.'"
An interesting and related question is how the laws can be tweaked, yet still conform to the anthropic principle. One could imagine a smaller universe, where the sentients would not be so spread out. Play with the equations, and run simulations. The neuroscientists will have to get involved once we understand sentience more.
A question is, though, do those laws apply at all times and places, or are we just "discovering" them here, and now? As far as I know, there's nothing prohibiting a gradual gauge change over time and space. Perhaps those innocuous gauge shifts really DO have an effect somewhere/when. What we generally call "laws" should be universally applicable (or their restricted domains should be stated), but what if they're only applicable here/now? Are they just shadows of higher-dimensional laws which may undergo sudden changes as some higher-dimensional phase change goes on?
Perhaps the arbitrary laws you can write down really do apply.
This all strikes me as a form of hidden variables theory. Or perhaps just cosmic navel-gazing.
We ARE creating the laws, but what we create them ABOUT is something we do not have control over. The universe and human evolution rolled those dice aeons ago. Yes, you COULD write a law that says gravity doesn't exist, IF the law you write permits the kind of observations we make regarding objects in space/time. In fact, this is an interesting example. The Einsteinian view is that gravity (in and of itself) doesn't exist. It is our perception of how objects behave in curved space time. In the other ring, you have physicists who are bound and determined to shoe-horn gravity into some grand design of particle physics, and are on a continuous (and IMHO, quixotic) quest for the Graviton.
So, you grab a brick, hold it out. Let go. It falls. The effect of it falling on release we can call "gravity", but whether gravity exists as a REAL force in the universe, or just some weird effect of space/time warpage is another issue. So, yes, you CAN write a law that says "gravity doesn't exist" as long as your law accounts for the behaviour exhibited in the test of your dropping the brick.
What is insightful about your brief post is the point that what we call "Scientific Laws" are merely descriptions of nature. The laws are Scientific, and are therefore, tentative. They will remain "true" only as long as they can be proven to be true. Once some genius comes along and disproves it, or, more likely, incorporates it into some larger understanding, it will cease to be "true". Science is not based on absolute permanent truth. Scientific truth is ALWAYS provisional. It is so, as it is a product of language - a tool of our species.
RS
Shoes for Industry. Shoes for the Dead.
The argument I've found most persuasive, and IIRC correctly from a Berkeley physics seminar umpty years ago by Hawking, shared by at least some first-rank cosmologists, is that the physical laws we have will ultimately prove to be the only possible logically consistent set.
That is, "alternate" universes are ipso facto impossible, because there is no other set of physical laws that are consistent with each other. And imagining them is somewhat like asking whether God can make a stone so heavy he can't lift it, or imagining being your own grandfather via a time-travel machine: a mere exercise in word-play, allowed only by the fact that English is a sufficiently illogical and ambiguous way of communicating that all kinds of nonsense can be put into words and "make sense" grammatically without making the least bit of sense logically.
When in fact, science is discovering the opposite.
Reductionism has been the prevailing school of thought in science for a very long time. We've assumed if we could break things down into their constituent pieces, then we'd understand the bigger picture stuff pretty readily.
Now scientists are starting really get a sense that the more they pull it apart into wee pieces, the less we know about how it all got put together in the first place. The complexity of what we have is, at present, far greater than our understanding of how the bits work.
In actuality, you end up like a child who has taken apart a complicated toy, and can't figure out how to put it together.
Our knowledge has grown exponentially. But, the more we look at what we know, the more we realize the sheer scale of the stuff we don't know anything about. It's fascinating, but it's also humbling at the same time -- there's a lot more in some of these systems than we even have an inkling of understanding of.
I think we're reaching the point where simple reductionism, while still driving basic science, opens up far more questions than the number of answers we get. We just didn't know enough to know we had to ask these questions before.
Certainly, I don't think science is any where near answering the question of where the laws of nature came from. Philosophy and religion can try to do that, but their answers are just guesses as well -- some of this stuff isn't really "knowable" just yet.
Cheers
Lost at C:>. Found at C.
That is, "alternate" universes are ipso facto impossible, because there is no other set of physical laws that are consistent with each other.
I don't think the problem is with internal consistency of a set of laws, but compatibility with us. I believe Hawking argues that other sets of laws are possible, just incompatible with life. That our existence requires the current set. Regarding fundamental numbers (electron charge, etc): "The remarkable fact is that the values of these numbers seem to have been very finely adjusted to make possible the development of life."
You've a good point. I don't think we're talking at cross-purposes. I, at least, find these slashdot discussions to be ways in which to refine my own thinking a bit. If nothing else, it may make me a better communicator
I'm not proposing at ALL calling these hypothetical departures from "local" behavior "laws". If I gave that impression, I was mistaken and didn't mean to. I AM a proponent of testing those which have a chance of being true and which we have a chance of testing. I think that probably every scientist (or other philosopher, down to many young children) has pondered this question at one depth or another. It is nice that the NYT covered Davies' thoughts about this stuff, but it's nothing new in the philosophy of science (as I'm sure you well know, and as others in this discussion have pointed out).
I'm also somewhat saddened by the standard in which "falsifiability" is held. I think that if something is falsifiable, it should probably be tested, and things that are not presently falsifiable are really rather weak as hypotheses. Things which will never be falsifiable (because of the physical impossibility of doing certain experiments, or the ability to "move the boundaries" which define the problem -- as in "Intelligent Design") are very probably worthless and most certainly impractical. However, they are still quite interesting, if for no other reason that they provide some illustration of the point at which one should probably STOP thinking about them, or putting any faith in them.
I've always been leery of this "jump" which our guesses about the world can make if we test them enough. As I understand it, a "theory" is quite analogous to a "theorem" in mathematics; it may be built up from very basic building blocks, which we suppose to be true, using small reasoning steps which we also suppose to be true. Theories are often eminently testable; if they are not, they may be a step or two beyond their building-block theories which ARE eminently testable (and tested), but we still suppose our reasoning holds in extrapolating to them.
A "law" may be based on very little reasoning, but just seems to work every time we happen to glance its way, whether we have a series of stepping-stones to it or not. I would say that Newton's law of gravitation (that with the force falling off as the inverse-square of the distance, and so forth) was very definitely a law until Minkowski and Einstein came along (and after them, as a special case), but no one could remotely map out a nice way of getting there from "simpler" principles. If one puts one trust in the process of getting to a conclusion, laws are often very slippery, tentative beasts, whereas theories are well-rooted and understood. Laws just happen to have never failed (which may be a much stronger argument for their validity, but wouldn't satisfy a pure mathematician at all).
I'm also of the opinion that based upon my ramblings above, something can easily be a "law" and a "theory" at the same time, if it has been shown to hold true every time we've (validly) tested it, and is built out of simpler steps. In this way, the "Theory of Evolution", in my opinion, is very probably a law, since it's both been tested so much, and is built upon some very well-tested blocks.
So many people (Platonists) think these laws exist outside of human experience, and it's so obvious that they don't. WHAT they try to describe does, but there's a big difference. We can say a^2 + b^2 = c^2, but the very notion of a triangle is completely circumscribed by human experience, and the notion of abstract notation is also a human thing. To say such a relation exists a priori is where I believe rationalism runs off the rails into a kind of metaphysics of "belief" as opposed to empirical science, and where empirical science mistakes itself for reality.
Existence is a tricky thing, because it is also purely a human concept. By claiming that mathematics does not exist outside of human experience you are also implicitly claiming that the universe itself does not exist outside of human experience. Everything we know about the universe has been derived from human experience, which is ultimately no more real or unreal than our experience of mathematics, since both experiences exist only within the human mind. There is no objective viewpoint from which to consider existence or reality. Our minds must approach both the universe and mathematics in exactly the same way; perform experiments, observe the results, make up theories about what is happening, and try to disprove them. From the human perspective mathematics is as much a part of the universe as matter and energy, so it is not absurd to claim that mathematics exists outside of human experience.