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Question on Possibility of Changing Constants

  1. Jan 4, 2013 #1
    Is it the case that the laws we have set for our universe and the proportionality constants which help define those laws are 'set in stone'?

    If our universe is changing all the time, (i.e. accelerating, expanding) is it not the case that these laws could change over time? Does the entropy of a system (the universe) have anything to do with this?

    Follow up question, is it the case that EVERYWHERE in the universe follows our laws? I know that any law involving the gravitational forces should be expected to have a different proportionality constant due to the different masses and radii of separation of the bodies involved, however do the same general principles hold, or are we not sure?

    Perhaps I'm in over my head, this question has been answered, or doesn't make any sense, but either way if you could lead me in the right direction, that would be great.
  2. jcsd
  3. Jan 4, 2013 #2

    Simon Bridge

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    Laws who has set for our Universe? I wonder that you are attributing rather a lot of power to science here - either that or anticipating a particular kind of answer?
    How do you mean "set in stone"? Do the physical constants change with time? Is that what you are asking?
    They certainly could - the trick with science is to find evidence that they have... speculation is easy.
    That is the general assumption - there is a speculation that the Laws of Nature depend on being observed and, therefore, may be different (depending on the outcomes of local experiments - iirc: Greg Egan has a novel based on this idea) in different parts of the Universe ... but it is just that: speculation. Certainly all the evidence to date is that the laws we can test, like gravitation, are unchanged over all the distances we can see and as far back as we can see. At least, there have been no glaring inconsistencies that can be accounted for by suggesting that the Law of Gravity is different in different places.

    I think the right direction for you would be a study of the philosophy of science ... that will acquaint you with the underlying assumptions that guide the work of scientists and why these are useful assumptions.

    However - a related question, that the "fundamental" constants may have changed, is a subject of ongoing investigation.
    Generally we can rely on them changing so slowly that we don't have to worry about it during the lifetime of any experiment we can arrange.
  4. Jan 9, 2013 #3
    Everything you said seems to be consistent with my presumptions I had.
    I wasn't looking for any particular answer in my first sentence, just poor articulation on my part. I know science didn't SET laws for the universe, but merely attempts to describe how a system acts in our universe.

    A follow up question, is there any evidence of laws changing rapidly, that is an observable difference?
    For example, most scientist believe in geomagnetic reversal, now, this is a process that takes thousands of years and certainly not instantaneous, but wouldn't this significantly change the laws?

    edit: I know we haven't been around long enough with the tools to test this on Earth, however could we possibly observe this on other plants with a magnetic field?
  5. Jan 9, 2013 #4

    Simon Bridge

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    Hmmm? I think scientific research is more ambitious than that. Scientific endeavor, broadly, attempts to discover how the Universe actually works ... not just describe what happens. But I know what you mean.

    Need to be careful about what you are calling "laws" though. Scientists tend not to use the word, other than poetically, these days.

    I was careful, previously, to talk about "fundamental constants". That was to prep you.
    These would be things like the charge on an electron, the speed of light, and Plank's constant.
    Strenuous attempts have been made to discover if these constants have ever been different and nothing has come to light ... except maybe some ideas about what happened as the Universe was coming into existence. You can find a lot of stuff just googling the question (and subjecting the information to some crackpot test.)

    No - geomagnetic reversal is well within known Laws of physics.

    Possibly. i.e. if we had a spacecraft with a compass on it in orbit at the time.

    My understanding is that there is evidence for past reversals in Earth's geological record though - and the phenomena is consistent with computer models of what we know about the geomagnetic dynamo.

    [1] I don't think "believe" is the right word to use in connection with positions that are held scientifically ... I usually like to contrast "scientific belief" which is based on the weighting one gives to different empirical evidence with "religious belief" which is based on faith. I've found myself in too many evolution vs creation arguments for that. In the religious sense, scientists don't believe anything... any idea may be overturned. Some ideas have withstood many very strenuous attempts to overturn them to the extent that they get used as the basis for further research (on that understanding).

    If you read through the posts of people with the "science advisor" tag, they tend to try to avoid some words ;)
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