Are Physical Constants Really Constant?

Do the inner workings of nature change with time?














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In 1962 P. James E. Peebles and Robert Dicke of Princeton University first applied similar principles to meteorites: the abundance ratios arising from the radioactive decay of different isotopes in these ancient rocks depend on α. The most sensitive constraint involves the beta decay of rhenium into osmium. According to work by Keith Olive of the University of Minnesota, Maxim Pospelov of the University of Victoria in British Columbia and their colleagues, at the time the rocks formed, α was within two parts in 106 of its current value. This result is less precise than the Oklo data but goes back further in time, to the origin of the solar system 4.6 billion years ago.

To probe possible changes over even longer time spans, researchers must look to the heavens. Light takes billions of years to reach our telescopes from distant astronomical sources. It carries a snapshot of the laws and constants of physics at the time when it started its journey or encountered material en route.

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Astronomy first entered the constants story soon after the discovery of quasars in 1965. The idea was simple. Quasars had just been discovered and identified as bright sources of light located at huge distances from Earth. Because the path of light from a quasar to us is so long, it inevitably intersects the gaseous outskirts of young galaxies. That gas absorbs the quasar light at particular frequencies, imprinting a bar code of narrow lines onto the quasar spectrum.

Whenever gas absorbs light, electrons within the atoms jump from a low energy state to a higher one. These energy levels are determined by how tightly the atomic nucleus holds the electrons, which depends on the strength of the electromagnetic force between them—and therefore on the fine-structure constant. If the constant was different at the time when the light was absorbed or in the particular region of the universe where it happened, then the energy required to lift the electrons would differ from that required today in laboratory experiments, and the wavelengths of the transitions seen in the spectra would differ. The way in which the wavelengths change depends critically on the orbital configuration of the electrons. For a given change in α, some wavelengths shrink, whereas others increase. The complex pattern of effects is hard to mimic by data-calibration errors, which makes the test astonishingly powerful.

Before we began our work 11 years ago, attempts to perform the measurement had suffered from two limitations. First, laboratory researchers had not measured the wavelengths of many of the relevant spectral lines with sufficient precision. Ironically, scientists used to know more about the spectra of quasars billions of light-years away than about the spectra of samples here on Earth. We needed some high-precision laboratory measurements against which to compare the quasar spectra, so we persuaded experimenters to undertake them. Initial measurements were done by Anne Thorne and Juliet Pickering of Imperial College London, followed by groups led by the late Sveneric Johansson of Lund Observatory in Sweden, Ulf Griesmann of the National Institute of Standards and Technology, and Rainer Kling, now at Laser Zentrum Hannover in Germany.

The second problem was that previous observers had used so-called alkali-doublet absorption lines—pairs of absorption lines arising from the same gas, such as carbon or silicon. They compared the spacing between these lines in quasar spectra with laboratory measurements. This method, however, failed to take advantage of one particular phenomenon: a change in α shifts not just the spacing of atomic energy levels relative to the lowest energy level, or ground state, but also the position of the ground state itself. In fact, this second effect is even stronger than the first. Consequently, the highest precision observers achieved was only about one part in 104.


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  1. 1. slayerwulfe 01:17 AM 12/31/11

    Midway into the forth paragraph I encountered this statement."So far researches have no idea why our combination was selected." Recently Stephan Hawking has stated and I am in total agreement with it "That the universe has no room for God" I am going to use the term value in reference to the word "selected" because it seems to imply that there is some (higher)incorporeal nonlinear intelligence making decisions or guiding, and I'm just not seeing it as anything other than an unfortunate choice of words. To state it simply I find it extremely conceivable that matter does not exist but is only a 'byproduct' manifest through extreme forces.

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  2. 2. slayerwulfe 01:41 AM 12/31/11

    Well Mr. Natural and Witch Dr. where are you for this one, does the incompetence of Wikipedia limit your ability to respond.

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  3. 3. c.o.corroboration 03:17 AM 12/31/11

    most of those who are fortunate enough to comprehend do not wish to fuel your hype. we would hope that you think and act with wisdom in future endeavors.

    sincerely, grandmother willow

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  4. 4. c.o.corroboration 03:22 AM 12/31/11

    if god exists, then why doesnt god exist!?

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  5. 5. slayerwulfe in reply to c.o.corroboration 03:59 AM 12/31/11

    The discussion is about string theory do you have anything to say or not. Please do not direct the conversation towards me with your mindless philosophical garbage about God or how unfortunate you are in comprehensive skills.
    A question: what is the purpose of your existence here if your not interested in the topic.

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  6. 6. jtdwyer 03:59 AM 12/31/11

    I have to thank the authors, Barrow and Webb for their very approachable explanation of their seminal research, and Scientific American for publishing this excellent article.

    As a layperson, I have to wonder whether the use of redshift to evaluate the variability of fundamental constants might introduce some potential error to the extent that cosmological models used to estimate distance from redshift would be affected by any variability of cosmological constants.

    The directional variation in the evaluation of a is very interesting. To me it suggests that it (and local rates of expansion) might vary depending on the local density of matter, given the apparent variation in what is considered to be the large scale structure of the universe. As I think had been suggested earlier as a potential explanation for type Ia supernovae studies thought to indicate the universal acceleration of expansion, large regions devoid of matter might expand at rates different than regions denser in matter, since gravitation essentially might locally resist it.

    While astrophysicists presume that expansion is omnidirectional, if we can only observe objects within a small slice of a spherical universe, for example, this may be an illusion. Using the inflating balloon model of the expanding universe, on the surface all objects may appear to be expanding away from any observer but an impossibly permanent or external observer could see that expansion of the balloon directionally proceeds from a central point of origin. As expansion progresses its local direction becomes increasingly lateral - omnidirectional at small scales...

    It would be most interesting to understand which of a's contributing factors might be responsible for any detected change...

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  7. 7. jtdwyer in reply to slayerwulfe 04:05 AM 12/31/11

    If you concluded that the subject was merely string theory you might should read the other 5 pages...

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  8. 8. slayerwulfe in reply to jtdwyer 04:54 AM 12/31/11

    I apologize to you sincerely because the comment was only to eliminate a person that had no reason for being here. I would be interested in hearing anything you have to say.
    in closing my apology to your sensibility
    slayerwulfe cave

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  9. 9. jtdwyer in reply to slayerwulfe 05:16 AM 12/31/11

    IMO, there are no restrictions on who should comment, only that the comments be to some extent relevant to the subject, not be generally offensive and not be personally directed. To some extent I violated my own third guideline - I apologize for that.

    BTW, I generally agree with most of your first comment.
    Thanks for your explanation and kind remarks.

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  10. 10. Tony_Who 09:44 AM 1/15/12

    This is a good article and it is good to have a serious study of the subject.

    Focusing on dimensionless (unitless) quantities appears to be a good approach. With respect to Universal physics, it may be that any quantity with units will not be a true constant, but ratios of certain quantities will always be the same.

    Since the dimensionless quantities are usually ratios or fractions, it will be interesting to see if any new fractal patterns will be discovered.

    Thanks,
    -Tony

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  11. 11. curmudgeon in reply to slayerwulfe 10:36 AM 1/15/12

    "I am going to use the term value in reference to the word "selected" because it seems to imply that there is some (higher)incorporeal nonlinear intelligence making decisions or guiding"

    It implies no such thing as far as I can see however inconvenient that may be to your determination to get your combative atheism in somewhere. When a machine selects a number for a lottery draw does that imply anything of the sort? Of course not!

    Moreover, I am bound to point out that "the Universe has no room for God" is entirely vacuous as a philosophical statement and questionable even as a scientific one (unless you accord divine knowledge to Stephen Hawking and thereby replace a non-corporeal God with one of us!) If you pre-define the Universe as that which science can investigate then you automatically preclude anything physical or non-calculable. This ontological argument which is betrayed in statements like "the best candidate for a theory of everything, the variant of string theory called M-theory, is self-consistent only if the universe has more than four dimensions of space and time" is every bit as specious and falsifiable as that for the existence of God and it's high time that science recognised this fact. It is little wonder that the popular perception of science is that it's just a case of making it up as you go along to fit your favourite idea(l) when so much of it is increasingly based on assumptions that cannot ever be proven. No matter how sophisticated the scientific model of the Universe gets in the next century or so it will only ever be a model and never the Universe itself.

    As it happens philosophers on both sides of the argument have long acknowledged that God, by definition, cannot be 'part' of the Universe in any sense which would make deity perceptible to science and that science therefore has nothing to say on the matter of God. The old maxim has never been truer "whereof one cannot speak thereof one must be silent"! and therefore we must conclude that, whether seeking to dispel or prove God's existence anyone using science (evidential or theoretical) is either a charlatan or a fool.

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  12. 12. rloldershaw 10:37 AM 1/15/12


    A unique and natural explanation for the physical meaning of the fine structure constant can be found at:

    http://arxiv.org/abs/0708.3501

    This new cosmological paradigm can also explain the reason for, and the solution of, the vacuum energy density crisis:

    http://arxiv.org/abs/0901.3381

    The new discrete fractal cosmology can also retrodict and explain the subatomic particle mass spectrum:

    http://arxiv.org/abs/1002.1078

    And shed light on many other conundrums in physics:

    http://arxiv.org/a/oldershaw_r_1

    Why is the new discrete fractal paradigm ignored, when recent research has put string theory, supersymmetry, and quantum gravity models in serious doubt, and the Standard Model of particle physics is known to be highly heuristic? You tell me.

    Robert L. Oldershaw
    Discrete Scale Relativity

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  13. 13. curmudgeon in reply to curmudgeon 10:39 AM 1/15/12

    Obviously I mean ... preclude anything NOT physical ... above!

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  14. 14. Tony_Who 10:51 AM 1/15/12

    A few other ideas about the apparent anisotropy of space are:

    Solids, liquids and gases have state functions related to state variables. For example, a phase diagram for water is a 3D graph with temperature, pressure and density as the axes. Based on the values of the three state variables, the graph will show if the H20 is ice, water or steam. The 3D graph is divided into volumes representing each phase. Phase change boundaries of melting, boiling, etc are shown as surfaces between the volumes. There is a single point called the Triple Point on the graph where all three phases are present. Since the triple point of water is well defined, it is used to calibrate thermometers.

    Similar to how materials have state functions related to state variables, perhaps space itself has state functions related to fundamental quantities. For example, space may behave differently depending on the local electric, magnetic and gravitational field intensities or from any other kind of energy that is contained or passing through the space. Space itself could even go through phase changes, depending on its local environment. Perhaps “space elements” arrange themselves into crystal structures, and each structure has different densities and properties. Diamond and graphite have very different properties even though they are made from the same element. The difference in properties comes from their structure. Can space elements arrange themselves in different structures to make allotropes of space?

    Perhaps space is a solid made of space elements. Light is a vibration within the solid that propagates as a wave, while matter is a combination of vibrations within the solid that makes standing waves.

    Thanks,
    -Tony

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  15. 15. KimberlyPeacock 06:45 AM 1/17/12

    I think that this observation is linked to the observation recently about the speed of light and time.
    Time and space are variable much like state variables.
    I have intuited this as it seems to make sense to me.
    The problem I have is that its as if we have brought back the ether in a different form.

    It would be interesting to model this with activation energies, and see what the results look like.

    Infinity implies that at a fundamental expression that causality is meaningless as everything is symmetrical and the same. Causality only kicks in when you have asymmetry. Wrapping ones head around a world with no causality, no beginning or end, is as befuddling as wrapping oneself around some God of the same dimensions.
    What is time but a measurement of change, which means asymmetry and the lack of sameness?
    IS there some energy density function and fundamental force which is capable of describing everything we see?

    We may not return to the exact microstate, but we do not have too, just return to the same average energy, within the same density in space/time.

    Models will drive you crazy, only the experimental and causality will end the madness.

    I look forward as more scientists dig into this area, and challenge old assumptions. I think its exciting. As Feynman said, attack the problem from a different point of view.

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  16. 16. gmperkins 08:56 PM 1/17/12

    That was a very interesting read and I'll have to get the full article. I will remain skeptical until measurements are duplicated (obviously a difficult task, and one the authors repeat). I also wonder about a number of what ifs. It is too bad we can't get a ways from earth (many light years away) to do testing.

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  17. 17. christinaak 04:04 PM 1/20/12

    an evolutionary cyclic model remains as the best explanation for the current fine-tuning of parameters (constants) that make our present universe possible. i am confident within the next 50 years this model will be taught as the accepted model in high school science classes. as regards the the question of whether these constants may vary during the course of given cycle, i suggest another possibilty in my book. if the cosmic space-time geometry is hierarchically stratified then it may be that there are stratum dependent variations in the nature of, and value of constants. in my own model the universe has 3 strata with a total of 12 dimensions (9 space,3 time) and each stratum has its own numerical values for the constants c, G, and h. it is these stratum dependent variations in fundamental constants that explain the peculiarities of quantum behavior as particles oscillate through the tri-stratum space-time geometry. because of the stratum dependent variations in the constant c particles experience variations in time dilation as they oscillate thru the tri-stratum framework. also because the velocity of c is progressively higher in the lower strata, entangled particles can communicate faster than the velocity c as measured in the uppermost stratum (the 4 dimensional world we are familiar with).

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  18. 18. American Muse in reply to curmudgeon 10:51 PM 1/20/12

    The problem, dear curmudgeon, is in ourselves and not in our stars.

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  19. 19. Quinn the Eskimo 10:56 AM 1/22/12

    Universal constants have always struck me as one of either; Science fact, determined by experiment. Or, a fudge factor because some theory didn't work in its math.'

    Quizzle; If you were traveling at the speed of light, I know -- this is a supposition -- and you turned on your head light; Would the photons emitted go forward at the speed of light from you? Or would they fall still in relation to your craft.

    From the stationary observer, noting *you* are traveling at the speed of light, would your photons travel in pace with your craft, or would they be traveling at a warp speed?

    If the light is traveling at light/squared, how would the stationary observer detect it?

    Is the speed of light truly constant (which we KNOW it is not) or relative? Light is relative to the material in which it is traveling, no?

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  20. 20. bucketofsquid 03:36 PM 1/27/12

    Fascinating article that I only understood a small part of. I'm pleased to see that the authors are actually fairly open minded and admit more than once where they had to question their own assumptions. I just wish I understood more of this. It is a shame that much of the forum discussion turned into name calling.

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  21. 21. janard in reply to slayerwulfe 03:48 PM 1/28/12

    Whether God exists or not, "sense" seems to be on its way to non-existence.

    1. From the beginning, Scientific development is based on observation, hypothesis, mathematical basis, re-observation and refinement.
    2. However in the 21st century, mathematics has overtaken observations in usurping center stage. Many of the respected theories are "unfalciable" which exist only on the mathematical plane.
    3. Based on the past we know that every theory had hundreds of mathematical proofs, corrolaries and contradictions and only the one that survived observations stuck.
    4. This proves that we can't just accept any mathematical theory just because "it explains observed facts", fully knowing that there can be many mathematical alternatives but one truth.
    5. I don't agree with Mr. Hawking, Mr. Suskind or some others who are putting forth unfalciable theories only on the basis of mathematics.

    So I strongly believe that we should not delve in to a discussion of faith or God in these confusing times. Science is in danger of becoming a jumble of mathematical fancy and magic (in the guise of Science, of course). In my opinion, any one who says the questions "why, when and where and how" don't apply to behavior of quantum particles (just because we don't understand) is not a real scientist.

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  22. 22. rwstutler 04:48 AM 2/4/12

    Amazing - we may be able to detect changes in the fundamental and defining properties of the frame of reference which we exist within. Which sugests the existence of a larger frame of reference in which our frame exists. Fundamental science is way cool.

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  23. 23. debu 05:27 AM 3/29/12

    DURGADAS DATTA published a paper --MISJUDGEMENT BY NEWTON where he said that our universe is non isotropic gravitoetherton soup which swirls and rotate causing rotation of planets and galaxies with it and when gravitoethertons is focussed towards center of earth we see objects falling etc etc . He also predicted that light speed is a variable phenomena due to variation of field density of gravitoethertons soup and as such all constants and laws also variable in vast space due to non isotropic soup factor which he also called ether of our earlier days and now we also call this as WIMPS or DARK ENERGY. These were published in ASTRONOMY.NET in year 2002 and later in BALLOON INSIDE BALLOON THEORY--of matter and antimatter universe on opposite entropy path it was explained that gravitoethertons are produced by annihilation of matter and antimatter at common boundary of two universes and injected into our universe as ether or dark energy causing gravity,other laws,constants at different part of universe as per density of this gravitoethertons soup and we will observe laws and constants are varying. He modified NEWTONS LAW as F=P.G.M.m/R.R where P is factor of permeability as in COULOMBS LAW. these ideas of DURGADAS DATTA WERE PUBLISHED IN YEAR 2002 WHEN HE SAID BOTH NEWTON AND EINSTEIN ARE VERY MUCH WRONG DUE TO NON ISOTROPIC ETHER FILLED UNIVERSE. The idea of opposite entropy path also mentioned which gives us a idea of eternal recyclic universe as one universe will reach tends to zero entropy and a big bounce will occur causing again two universes due to CP VIOLATION and one universe by chance will start a structure on remaing big black holes escaped evaporation of HAWKINGS and by chance a in billion chance will present a universe as ours where a cozy corner giving suitable laws may produce life and even intelligent life. Actually these twin universes are infinite in infinte MEGA UNIVERSE. So what you are talki8ng of theory of everything or string theory etc etc --are mad or what. Beyond comprehension my dear NOBEL WINNERS all our knowledge is bound to change and our thinkig has to be beyond any imagination--more next issue and for more details write to-- durgadas.ddatta@gmail.com.

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  24. 24. radobozov in reply to Tony_Who 06:30 AM 12/18/12

    "The difference in properties comes from their structure." Function precedes structure, as phase 'spaces' are limited, while observables are unlimited. Structure is a computation of diffract ability caused by the interference of particles/strings/waves. Therefore properties comes from defining space - matter/antimatter occupying time determined by interference of particles/strings/waves. One can only observe time. Because space has been accepted to be unified to time due c , and energy to mass due h , the fine structure will be solely dependent on INTERFERENCE due permeability of light through a given 'substance/media' Therefore alpha is not a true constant it self as it is build upon constants solely taking density function as a measure of interference.

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  25. 25. radobozov in reply to janard 07:49 AM 12/18/12

    Math language is an abstraction of tools that describe relationship between numbers. Chemical language is an abstraction that describes observables relationship based on interpretation of forces.
    If the Earth were made out of a pure diamond/carbon, there would be NO gravity.
    There is no such a thing as factor of permeability P, there is only a factor of interference set by time-interference of particles/strings/waves.
    We have to answer the question what is life by the premise of how it can be modeled.In order to transition from how to what, one may have to get to the acceptance that observation is relative while interference is absolute. The more compressed mass is relative to carbon in the continuum of matter/time, the more expansion of discrete energy/spaces. We interpret information due carbon-X interfering systems in consciousness emerging into all reality - dreams, imaginations, direct observations. The periodicity of atomic properties can reveal many claims in certainty, that C properties will never be absolutely like Si and we, life, will never be an outcome of a nuclear reaction where strong forces operate. 'God' works with weak forces , thus spanning 'time'. It does not mean weak forces and strong forces have no relationship. Theories are adjusted/refined to observations as is the equality of quantity/charge of # of protons ratio to electrons despite difference in mass in chemistry. It that sense reduced plank constant will deviate due permeability of light of frequency/energy suggesting that transformation of electrons to positrons due interference will depend on space itslef. Again, + and - is part of an abstracted language, still a charge opposition may not be the origin of duality. We only need energy that is self sustainable, that would be a constant explaining periodicity of time and formation of discrete fractals/structures.

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  26. 26. jesse_a_b in reply to slayerwulfe 12:42 PM 4/2/13

    Yet information present in life on Earth cannot be created by chaos, the Kolmogorov complexity of a system can never increase. Evolution theory doesn't even come far to explain it, and this is a much bigger problem than the selection of physical constants.

    Another big problem : human self-awareness, the spectator in your own mind, which cannot and will never be explained by our very limited human understanding.

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