Image: Courtesy of Wolfgang Steffen Instituto de Astronomía, UNAM and Cosmovisión
In Brief
- Physicists routinely assume that quantities such as the speed of light are constant: they have the same values everywhere in space and time.
- The authors and their collaborators have called that assumption into question. By comparing quasar observations with laboratory reference measurements, they have argued that chemical elements in different regions of the universe may be absorbing light differently than the same elements on Earth. The data suggest that one of the constants, known as the fine-structure constant, drifts gradually by a few parts per million across the entire observable universe.
- Small though it might seem, this change, if confirmed, would be revolutionary. It could be a sign that space has extra dimensions.
Some things never change. physicists call them the constants of nature. Such quantities as the velocity of light, c, Newton’s constant of gravitation, G, and the mass of the electron, me, are assumed to be the same at all places and times in the universe. They form the scaffolding around which the theories of physics are erected, and they define the fabric of our universe. Physics has progressed by making ever more accurate measurements of their values.
And yet, remarkably, no one has ever successfully predicted or explained any of the constants. Physicists have no idea why constants take the special numerical values that they do (given the choice of units). In SI units, c is 299,792,458; G is 6.673 × 10–11; and me is 9.10938188 × 10–31—numbers that follow no discernible pattern. The only thread running through the values is that if many of them were even slightly different, complex atomic structures such as living beings would not be possible. The desire to explain the constants has been one of the driving forces behind efforts to develop a complete unified description of nature, or “theory of everything.” Physicists have hoped that such a theory would show that each of the constants of nature could have only one logically possible value. It would reveal an underlying order to the seeming arbitrariness of nature.
In recent years, however, the status of the constants has grown more muddied, not less. Researchers have found that 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—as many as seven more. One implication is that the constants weobserve may not, in fact, be the truly fundamental ones. Those live in the full higher-dimensional space, and we see only their three-dimensional “shadows.”
Meanwhile physicists have also come to appreciate that the values of many of the constants may be the result of mere happenstance, acquired during random events and elementary particle processes early in the history of the universe. In fact, string theory allows for a vast number—10500—of possible “worlds” with different self-consistent sets of laws and con-
stants. So far researchers have no idea why our combination was selected. Continued study may reduce the number of logically possible worlds to one, but we have to remain open to the unnerving possibility that our known universe is but one of many—a part of a multiverse—and that different parts of the multiverse exhibit different solutions to the theory, our observed laws of nature being merely one edition of many systems of local bylaws.
No further explanation would then be possible for many of our numerical constants other than that they constitute a rare combination that permits consciousness to evolve. Our observable universe could be one of many isolated oases surrounded by an infinity of lifeless space—a surreal place where different forces of nature hold sway and particles such as electrons or structures such as carbon atoms and DNA molecules could be impossibilities. If you tried to venture into that outside world, you would cease to be.
Thus, string theory gives with the right hand and takes with the left. It was devised in part to explain the seemingly arbitrary values of the physical constants, and the basic equations of the theory contain few arbitrary parameters. Yet so far string theory offers no explanation for the observed values of the constants.
A Ruler You Can Trust
indeed, the word “constant” may be a misnomer. Our constants could vary both in time and in space. If the extra dimensions of space were to change in size, the “constants” in our three-dimensional world would change with them. If we looked far enough out in space, we might begin to see regions where the “constants” have settled into different values. Ever since the 1930s researchers have speculated that the constants may not be constant. String theory gives this idea a theoretical plausibility and makes it all the more important for observers to search for deviations from constancy.
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26 Comments
Add CommentMidway 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.
Reply | Report Abuse | Link to thisWell Mr. Natural and Witch Dr. where are you for this one, does the incompetence of Wikipedia limit your ability to respond.
Reply | Report Abuse | Link to thismost 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.
Reply | Report Abuse | Link to thissincerely, grandmother willow
if god exists, then why doesnt god exist!?
Reply | Report Abuse | Link to thisThe 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.
Reply | Report Abuse | Link to thisA question: what is the purpose of your existence here if your not interested in the topic.
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.
Reply | Report Abuse | Link to thisAs 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...
If you concluded that the subject was merely string theory you might should read the other 5 pages...
Reply | Report Abuse | Link to thisI 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.
Reply | Report Abuse | Link to thisin closing my apology to your sensibility
slayerwulfe cave
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.
Reply | Report Abuse | Link to thisBTW, I generally agree with most of your first comment.
Thanks for your explanation and kind remarks.
This is a good article and it is good to have a serious study of the subject.
Reply | Report Abuse | Link to thisFocusing 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
"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"
Reply | Report Abuse | Link to thisIt 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.
Reply | Report Abuse | Link to thisA 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
Obviously I mean ... preclude anything NOT physical ... above!
Reply | Report Abuse | Link to thisA few other ideas about the apparent anisotropy of space are:
Reply | Report Abuse | Link to thisSolids, 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
I think that this observation is linked to the observation recently about the speed of light and time.
Reply | Report Abuse | Link to thisTime 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.
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.
Reply | Report Abuse | Link to thisan 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).
Reply | Report Abuse | Link to thisThe problem, dear curmudgeon, is in ourselves and not in our stars.
Reply | Report Abuse | Link to thisUniversal 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.'
Reply | Report Abuse | Link to thisQuizzle; 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?
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.
Reply | Report Abuse | Link to thisWhether God exists or not, "sense" seems to be on its way to non-existence.
Reply | Report Abuse | Link to this1. 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.
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.
Reply | Report Abuse | Link to thisDURGADAS 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.
Reply | Report Abuse | Link to this"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.
Reply | Report Abuse | Link to thisMath 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.
Reply | Report Abuse | Link to thisIf 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.
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.
Reply | Report Abuse | Link to thisAnother big problem : human self-awareness, the spectator in your own mind, which cannot and will never be explained by our very limited human understanding.