Are the laws of physics firmly established and unchangeable?

This thread had a comment there that made me wonder. It’s asserted there that the laws of physics cannot, and will not EVER, change - that they are an immutable part of reality, and that it’s basically impossible that what we know will ever be disproven or altered.

I can certainly see that it COULD be true, but I’d like to know if it IS. My knowledge of science is woefully lacking in this department.

I do believe the core laws are so firmly established that short of discovering a complete scientific fuck-up, or previously unregistered factors (I.e. it actually IS God making the ball fall down when you drop it, or something) they will not be changed, per se. Rewritten for clarity, possibly, but not changed to meaning something different than they are now.

Of course, I have no idea of how the build-up of a completely different planet system could affect those laws, at all.

You mean our current understanding of the laws of physics, or the actual laws themself?

If the former – of course those can (and often do) change.

If the later – well, it depends on what you mean. For example, in the brief microseconds after the Big Bang, conditions appeared in the universe regarding temperature & pressure & such that are impossible now. Particles simply acted differently back then than they do now. But does that mean the laws of physics changed? We’re able to describe those conditions back then using our current laws, yet those conditions are impossible now. So do you count that as a change?

And assuming it turns out that the universe will eventually end in a Big Crunch (which most scientists no longer believe, but the possibility is still there), then eventually the universe will end up in another super-dense singularity and the current laws of physics won’t be able to describe that.

Finally, though, you get into philosophy. Just because gravity worked yesterday and the day before and the day before and the day before, do we really know it will work tommorow? A scientist would say yes; but a philosopher would say no.

Many physical constants e.g. G, c, etc might conceivably be slowly changing and this has been suggested by several people over the years.

Pish…what we know as the laws of physics are based upon our understanding and synthesis of empirical observations, organized into mathematical models which resemble (in progressively greater precision) the behavior we observe. This doesn’t mean that our understanding of basic physical laws is complete, or even that it isn’t significantly flawed; in the middle of the 19th century, prior to the advent of thermodynamics, electrodynamics, relativity theory, and quantum mechanics, it was declared by many that physics was a closed, complete with Newtonian mechanics with only a few addenda to wrap it all up and move on to really interesting problems.

Now we know much more about the physical laws of the universe…and fundamentally what we know is that our understanding is seriously incomplete on both the scale of fundamental interactions and cosmological effects, with a lot of gaps in between. It’s entirely possible that some revelation in quantum mechanics or cosmology would totally revolutionize physics as we know it, and any student of quantum mechanics worth his salt will immediately admit to having no understanding of the causative behavior behind the statistical nature of fundamental interactions; heck, even Niels Bohr admitted it: “It is wrong to think that the task of physics is to find out how nature is. Physics concerns what we can say about nature.”

However, we wouldn’t expect–to several orders of magnitude of precision–for this new understanding to change the way the world functions in a practical, everyday manner, except insofar as it might allow us to affect new technologies that give us capabilities currently realized only in the annals of science fiction. Newtowian mechanics, as outdated as it is, serves well enough that most engineers and scientists not working in the fields of advanced physics don’t even bother to learn the “real” rules behind the classical approximations. Things we know to be true today–say, the laws of orbital mechanics–will likely-to-the-point-of-certainty continue to be useful, even as we gain a true understanding of, say, quantized gravity or supersymmetic theory.

It’s not–unfortunately–as if discovering something new about the laws of physics will cause them to glance away and permit us to fly through the air, and hypotheses like that presented in the cited thread based upon this vague notion that “everything we know is wrong” are indulging in an inductive fallacy, assuming that a lack of complete understanding and possible exceptions to the existing ruleset require throwing out the baby with the bathwater. “All right, but apart from the sanitation, the medicine, education, wine, public order, irrigation, roads, a fresh water system, and public health, what have the Romans ever done for us?” Casting aside any attempt to rationalize the world based upon previously understood principles derived from empirical observation and repeatedly tested against failure would undercut any application of scientific rationality, and that leaves us with little more than superstition and shamanism which characterized the pre-Enlightenment Western civilizations and their backward adherence to whatever ideology or theology waxed most popular (or was most threatening) at the time.


I keep trying to get enough signatures to call a referendum on the Laws of Gravity, but the interest of my neighbours in such issues is next to zero. A real shame, really. I could use some flying.

You’re in luck - you live at a time when the human race has figured out how to fly without any need to alter any laws of physics.

You will need some additional apparatus, but rather clever versions are now readily available. I regularly strap myself into this one (about 540 lbs of carbon fiber, GRP and metal).

Well, I’m with you, Sapo. Down with gravity!

Ooh, I want! I used to fly gliders in VT. Mine was an Eastern Europen all-metal can that looked more like a Canberra than anything else. It still was a very gracious flyer for someone my size.

I was thinking more along this line, though. :wink:

To say that the laws of physics cannot change is a tautology, since anything that can change is, by virtue of being able to change, not a law of physics. And even if, say, the electromagnetic coupling constant were to change (a possibility which cannot be ruled out), then that would just mean that the law is the thing which governs how the constant changes, not the coupling constant itself.

On the other hand, we can never be certain that we know what the true laws are. No matter how many observations we make or experiments we do, there’s always the possibility that there’s some set of circumstances just around the corner which we’ve never observed, but under which circumstances, things would behave differently than we expect. Our understanding of the laws of physics can absolutely change, and has done so many times in history.

Don’t blame me; I voted for Velcro.

So did I - where in VT did you fly?

Perhaps it was a Blanik?

I want to say Sugarbush. I am not too sure. I only took a handful of lessons there. I believe my instructor was called Rick (darn, I suck at this). I got there through a friend (her initials are HC, she was very active at the club, you must know her if we are talking about the same place). We are talking 1998-99 here.

My plane had a low wing and a nose, not similar at all to the one on the photo. The only pic I have of it is printed. I will scan it and post it for you to check it out (it is on the kids’ room, won’t risk waking them up).