This is a post about constancy and inconstancy, one of my favorite topics. And about how alcohol can make you smarter.
There are many quantities that we call “constants of nature”. Of course, anything we call a “constant” is merely something that, empirically, appears to be constant, to the extent we can measure it. Everything we know comes from observation and experiment, and our knowledge is always limited by how good our measurements are.
We have pretty good evidence that a number of basic physical quantities are pretty much constant. A lot of evidence comes from the constancy of the colors of light waves (i.e. the frequencies of waves of electromagnetic radiation) that are emitted by different types of atoms, which appear to be very much the same from day to day and year to year and even across billions of years (neat trick! will describe that another time), and from here to the next country and on to the moon and to the sun and across our galaxy to distant galaxies. For example, if the electron mass changed very much over time and place, or if the strength of the electromagnetic force varied, then atoms, and the precise colors they emit, would also change. Since we haven’t ever detected such an effect, it makes sense to think of the electron mass and the electromagnetic force’s strength as constants of nature.
But they’re not necessarily exactly constant. One can always imagine they vary slowly enough across time or place that we wouldn’t have noticed it yet, with our current experimental technology. So it makes sense to look at very distant places and measure whatever we can to seek signs that maybe, just maybe, some of the constants actually vary after all.
[I wrote a paper in 2001 with Paul Langacker and Gino Segre about this subject (Calmet and Fritzsch had a similar one). This followed the observational claims of this paper (now thought false) suggesting the strength of electromagnetism varies across the universe and/or with time. A lot of what follows in this post is based on what I learned writing that old paper.]
Suppose they did vary? Well, the discovery of any variation whatsoever, in any quantity, would be a bombshell, and it would open up a door to an entirely new area of scientific research. Once one quantity were known to vary, it would be much more plausible that others vary too. For instance, if the electron mass varies, why not the W particle’s mass, which affects the strength of the weak nuclear force, and thereby radioactivity rates and the properties of supernovas? If the electromagnetic force strength varies, why not that of the strong nuclear force? There would be interest in understanding whether the variation is over space, over time, or both. Is it continuous and slow, or does it occur in jumps? One can imagine dozens of new experiments that would be proposed to study these questions — and the answers might reveal relations among the laws and “constants” of nature that we are currently completely unaware of, as well as giving us new insights into the history of the universe.
So it would be a very big deal. [Though I should note it would also be puzzling: even small variations in these constants would naively lead to large variations in the “dark energy” (i.e. cosmological “constant”) of the universe, which would potentially make the universe very inhomogeneous. However, we don’t understand dark energy, so this expectation might be too naive.] Since there’s no story about it on the front page of the New York Times, you can already guess that no variation’s been found. But a nice new measurement’s been done.
The New Measurement
The punchline: the nice new measurement of one especially interesting quantity — the ratio of the mass of the electron to the mass of the proton — shows no sign of variation, to much better precision than was possible ever before, and looking halfway across the universe.
Specifically, a group from Amsterdam and Bonn, consisting of Julija Bagdonaite, Paul Jansen, Christian Henkel, Hendrick L. Bethlem, Karl M. Menten, and Wim Ubachs, has written a paper whose abstract claims: “we set a limit on a possible cosmological variation of the proton-to-electron mass ratio μ by comparing transitions in methanol observed in the early universe with those measured in the laboratory. Based on radio-astronomical observations of PKS1830-211, we deduced a constraint of ∆μ/μ = (0.0 ± 1.0) × 10−7 at redshift z = 0.89, corresponding to a look-back time of 7 billion years.”
In other words, since the universe is 13.7 billion years old, they are looking at galaxies that are so far away that it has taken half the universe’s age for the light from those galaxies to make it to Earth… which means they are halfway across the visible universe, by some measure. And they are looking at electromagnetic radiation (in radio wavelengths) emitted by the molecule known as methanol, which isn’t a type of alcohol you would want to drink, but you might want to burn. They’re comparing what’s emitted by methanol in galaxies far, far away with what methanol emits on earth, and they can’t find any difference, to one part in 10 million.
This result is actually much more interesting and powerful than it sounds, because the ratio of the electron mass to the proton mass is sensitive to several important quantities in nature. So the measurement gives evidence against variation in numerous interesting constants of nature. Let me now explain why this is true, by explaining briefly where the electron mass and the proton mass come from. They have remarkably different origins.
The Electron Mass
Within the Standard Model of particle physics (the simplest equations for the known particles and forces that are consistent with current data — and for the purposes of this post I’ll assume the Standard Model is accurate and appropriate) the electron mass is the product of two quantities:
- the non-zero value of the Higgs field, whose presence gives mass to all the known elementary particles (but not the proton, which isn’t elementary! see below.)
- the strength of the interaction between the electron and the Higgs field, called the “electron Yukawa coupling”. (This interaction is quite weak, which is why the electron is one of the lightest known elementary particles.)
So the electron mass is pretty simple; it depends mainly on just two quantities.
The Proton Mass
The proton mass is quite a bit more subtle! There are several important ingredients, and they don’t enter in a simple way.
First, you may have heard that a proton is made of two up quarks and a down quark; you can find this statement everywhere. But this is a white lie; a proton is vastly more complicated than this. Indeed, the up and down quarks are much lighter than a proton is: the up and down quark masses are only 0.004 and 0.008 GeV/c² (with big uncertainties, because they’re really hard to measure) whereas the proton has a mass of 0.938 GeV/c²! If the white lie were true, then the proton’s mass would be given roughly by adding the down quark’s mass to twice the up quark’s mass. But it’s not. In fact, if the up and down quark’s masses were both doubled, there would barely be any effect on the proton’s mass at all! And here we’ll only be considering variations far below one part in a million.
So what does give the proton its mass?
The mass of the proton is set by a curious and crucial feature of the strong nuclear force. If you pull two electrically charged objects apart, the electric force between them will become weaker and weaker, falling as one over the distance squared. However, the strong nuclear force is different, as shown in Figure 1. if you take a quark and an antiquark that are extremely microscopically close together, the strong nuclear force between them will first become weaker, but then, at about a distance of a tenth of a millionth of a millionth of a centimeter (a centimeter is a bit more than 1/3 of an inch), the force will stop decreasing. Well, that special distance is called the “confinement scale” (let’s call it “R”), and at larger distances the “confinement force” holds the quark and antiquark together in a constant and firm grip from which they cannot (directly) escape.
Now how do we figure out the proton mass from this? Roughly speaking, trapping quarks and antiquarks and gluons in a little sphere with radius about equal to the confinement scale assures, by the uncertainty principle of Heisenberg, that the amount of energy in that little box will be related to Planck’s constant h divided by R and by the speed of light c. You see, Heisenberg tells us that you can’t know the position and the momentum of a particle at the same time; so if you squeeze down the position of a particle into a sphere of radius R (Figure 2), the particle will, on average, be speeding around with a momentum proportional to 1/R. So if the proton were to become smaller, its mass would increase. [That’s a little counter-intuitive, but that’s how things work in our quantum world! To make quantum things smaller requires effort and energy; that energy contributes to the mass of the object, since E = mc² (for an object that is stationary.)] Some little details ensue, but basically the proton mass is proportional to 1/R; roughly it equals h/(2πcR), times a number which has to be calculated on a computer and turns out to be about 5.
So now the question is: since the proton mass is determined by R, what determines R? Well, that’s quite interesting. R turns out to be affected by several more fundamental quantities. For instance, if you ask: how strong is the strong nuclear force at a distance scale where quantum gravity is important — the sort of question that theoretical physicists might ask when trying to make a complete theory of the world — the answer is that R depends exponentially on the answer! Just a 1% change in the strength of the strong nuclear force at very short distance can lead to a 10% change in R!
That’s not all. The confinement scale R is also affected somewhat by the masses of the top quark, bottom quark and charm quark, because of subtle effects of their fields (specifically, by effects often called “virtual particles”) on the way that the strong nuclear force changes with distance. Like the electron mass, the mass of each quark is related to the quark’s Yukawa coupling (i.e., how strongly it interacts with the Higgs field) times the non-zero value of the Higgs field.
Putting this altogether, the proton mass is sensitive to
- The strength of the strong nuclear force at short distances (to which it is very sensitive indeed)
- The non-zero value of the Higgs field
- The Yukawa couplings of the charm quark, bottom quark and top quark.
- And possibly the masses of other particles with strong nuclear forces that we haven’t yet discovered.
Quite a list!
The Implications
In short, the electron mass divided by the proton mass is a quantity determined by a plethora of interesting and more fundamental quantities in nature. The fact that there is no observable variation, at one part in 10 million across half the universe, in the ratio of the electron mass to the proton mass suggests that there is no variation, more or less at that level, in the short-distance strength of the strong nuclear force, the non-zero value of the Higgs field, and the Yukawa couplings of the electron, the charm quark, the bottom quark, and the top quark. Note: although both the electron mass and the proton mass depend on the value of the Higgs field, their dependence is different, and does not cancel in the ratio of the masses.
Of course, it is possible that several of these quantities are varying, and just by chance all the variation cancels out of the electron mass to proton mass ratio. But there’s no reason theoretically to expect that to happen; simple equations you might write down for how variations might occur don’t lead to a big cancellation. So there’s a caveat, but it is a small one.
Too bad! A discovery of variation would have changed particle physics, astrophysics, and cosmology forever. Experts will keep looking for variations in other quantities, and improving the precision of their measurements. But a powerful new result of this type still provides important information, knowledge that scientists will include in their future efforts to understand what underlies our strange, and strangely constant, universe.
77 Responses
Sorry wrongly clicked two times accidentally. Please delete this and the former.
The transmission of information in Quantum entanglement, the spooky correlation occurs instantaneously between two different frame of reference in space time, like Quantum superposition even separated by arbitrarily large distances – shows, the phenomenological physical effect(the quantum action) appear to travel exceeding the speed of light “c”.
If this is realized, a kind of Cherenkov effect could be felt in vacuum ?
The transmission of information in Quantum entanglement, the spooky correlation occurs instantaneously between two different frame of reference in space time, like Quantum superposition even separated by arbitrarily large distances – shows, the phenomenological physical effect(the quantum action) appear to travel exceeding the speed of light “c”.
If this is realized, a kind of Cherenkov effect could be felt in vacuum ?
No. In order to get a Cherenkov effect you need a *particle with electric charge* must be moving through the medium faster than light moves through that medium.
In entanglement, what is really happening when one particle is affected? Is there some sort of signal that moves between it an its partner? If so, how fast? Constant speed that differs depending on how far away the particles are? Can it accelerate or change direction? it’s certainly not a material signal in any sense.
And we could simply treat the entangled particles as one single object, you affect part of the object, you affect all of it at once, there is no distance between the different parts. Quite possibly the idea of needing to send a signal between two discrete objects is just an assumption we make from our human perspective.
It would be interesting to see an article here on entanglement.
Nice explanation Kudzu,
I stay with physical effect(the quantum action). Simple example is, our consciousness “signals” our body parts making “physical effect” possible – may be by electric impulse or photons.
With what you could compare the signals between entanglement ?
Quarks are fermions, gluons are bosons – have half-integer spin and integer spin respectively – means, there is no difference in describing quantum nature of material signal(fermions) and non material signal(bosons).
Only difference is, bosons could not make physical effect(the quantum action) ?
Until now, science didn’t explain material(fermion) alone could make physical effect ?
The problem is I am not sure there *is* a signal between entangled objects; from what I have read when one particle is altered the other is too, instantaneously, and there is no signal sent between them. I could be wrong, which is why I should much like he Professor’s opinion on the subject.
At base a signal is simply something being sent from one point to another. This may be a solid object like a letter, a particle either boson or fermion, or a ripple in a field. All that is required is that something exist that is moving from one place to another.
As the professor has discussed elsewhere on this site, the definition of ‘matter’ can be difficult; if you’re defining it as fermions then it is entirely possible for them to have a physical effect. We can turn particles like neutrons into waves, split and reflect them and bounce them off of each other. There is a rich array of fermion-fermion interactions that are definitely ‘physical effects’.
Thank you Kudzu,
“Gravity reverses entropy” – at least in our piece of universe, where dark matter gravity(quantum?) exists ?
“The only possible way for our solar system to be eternal is for some mechanism to continuously lower the entropy of it” – Dark energy lowers the entropy by keeping apart gravitational collision at quantum gravity – thus creating mass, re-energize or lower entropy ?
Unlike discrete digital information, Quantum information( physical information) cannot be cloned, the state may be in a superposition of basis values. The ability to manipulate quantum information enables us to perform tasks that would be unachievable in a classical context, such as unconditionally secure transmission of information.
However, despite this, the amount of information that can be retrieved in a single qubit is equal to one bit. It is in the processing of information (quantum computation) that the differentiation occurs – means…
We can only retrieve the 3D mirror image – like in 3-D printing technology ? – http://www.spiegel.de/international/business/3d-printing-technology-poised-for-new-industrial-revolution-a-874833.html
To process “fermion” level Physical information( quantum information) in quantum entanglement, Yukawa interaction should occur – like between, Higgs field and massless quark and lepton fields ?
My concept of information at the fundamental level of cosmic existence is david bohm,s concept of ( pattern creating ACTIVE information ) , you may call it ” pilot wave ” or whatever ….
As you know , physics try to reduce all macro to the micro and stops as the essence , the substance , the identity of the most basic level of the micro and for me this is active information without any medium , it is analogous to waving without medium of quantum fields.
As for infinite regress of the 3rd kind , it refers to ontological closed loops where A depends on B and B depends on A for their existence…….
i mean the generator depends on the fundamentals and the fundamentals depends on the generator UNLESS extra effector intervenes .
There are no such thing as infinite universe ;
1- If one universe , it would be now cold ,dead , void.
2- If chaotic ensemble with no beginning , all will pass thru a phase of G=zero , so ALL are now dead void.
3-True infinity cannot be combinations of finite parts ,so there is no actual infinity but there could be actual extension without limit in time or space.
The infinite universe has been largely ruled out, but there are still some models being propose, mostly by those who find inflation unsatisfactory.
The biggest problem with an infinite, non-inflating universe is what ‘resets’ the universe’s entropy; we can have an infinite universe that doesn’t end as a cold void if we assume that after some time the universe returns to its initial state, big bang-big crunch say, over and over. But due to the laws of thermodynamics, each cycle must be different, affected by those before it, which, if you go back into the past, eventually causes the model to break down. (Usually the cycles become infinitely short.)
However the standard inflationary model of a big bang and inflation proposes a universe that is, though not infinite, nearly so and expanding at a colossal rate forever.
The problem is that inflation moves faster than light, quite a bit faster, (Or rather it causes space to expand faster than light.) while ‘stop inflation’ moves at light speed. So when part of our universe stopped inflating, becoming the relatively stable kind of space we enjoy now, it could not convert all of the universe, and indeed, the inflating space is expanding far, far faster.
This even leads to a ‘multiverse’ since ‘stop inflation’ is a quantum process and can happen all over the place, creating endless numbers of universes separated by rapidly inflating space, never able to contact each other.
This is deeply unsatisfactory to me and I hope progress has been made on this front I am not aware of.
Kudzu, if you can imagine that the universe is not expanding, that the cosmological redshift is due to another effect (besides expanding space) and hence, no need for a Big Bang beginning or ad hoc fixes like inflation, apparently your only other objection is entropy. But that is not a real problem. Gravity reverses entropy. The “law” of entropy is only true if one excludes the effects of gravity. That is precisely what the originators of “law” of increasing entropy have done. Gravity was ignored because the scale of which the originators of that “law” worked with didn’t have gravity as a significant effect.
As an example, our solar system evolved from highly disordered state, under the influence of gravity, to a relatively ordered state where more energy is available to do work. (Place a solar panel anywhere in our solar system 5 billion or more years ago when it was just a nebula of dust and gas and see how much energy your solar cells could produce versus what can happen today!).
Ah, your example is a neat one but there are some problems with it. Our solar system today is quite ordered, but it is not more ordered than the primordial dust cloud when we take into account all of the radiation emitted by the cloud and sun over 4.6 billion years.
As the cloud shrank and ordered it lost gravitational energy in the form of heat, as well as flinging not an insignificant amount of mass out in the form of first gas, then dust then entire planets as things settled down. We are surrounded by a gigantic shell of emitted energy and mass. Order in one place has been compensated by greater disorder in another, like a fridge getting cooler as its motor warms the outside air.
So our solar system is constantly shedding disorder until our sun burns out and grows cold and crystalline. (Then even the planets will shed gravitational energy until the solar system is just one central object, the lowest possible energy state.) The only possible way for our solar system to be eternal is for some mechanism to continuously lower the entropy of it. (The simplest method would be to convert helium back into hydrogen spontaneously, adding energy to the sun, but it wouldn’t help the rest of the system.)
This is in fact part of the earlier ‘steady state’ theories, that new stars and mass kept appearing to replace that which burned out. It also ran into he problem that if the universe was infinitely old (and maybe large.) that all of space would have reached equilibrium with the stars, wherever we looked we would see starlight from some star or other and thus the sky would be as bright as the surface of the sun. this is known as Olber’s paradox: http://en.wikipedia.org/wiki/Olbers%27_paradox
Ah, your example is a neat one but there are some problems with it. Our solar system today is quite ordered, but it is not more ordered than the primordial dust cloud when we take into account all of the radiation emitted by the cloud and sun over 4.6 billion years.
As the cloud shrank and ordered it lost gravitational energy in the form of heat, as well as flinging not an insignificant amount of mass out in the form of first gas, then dust then entire planets as things settled down. We are surrounded by a gigantic shell of emitted energy and mass. Order in one place has been compensated by greater disorder in another, like a fridge getting cooler as its motor warms the outside air.
So our solar system is constantly shedding disorder until our sun burns out and grows cold and crystalline. (Then even the planets will shed gravitational energy until the solar system is just one central object, the lowest possible energy state.) The only possible way for our solar system to be eternal is for some mechanism to continuously lower the entropy of it. (The simplest method would be to convert helium back into hydrogen spontaneously, adding energy to the sun, but it wouldn’t help the rest of the system.)
This is in fact part of the earlier ‘steady state’ theories, that new stars and mass kept appearing to replace that which burned out. It also ran into he problem that if the universe was infinitely old (and maybe large.) that all of space would have reached equilibrium with the stars, wherever we looked we would see starlight from some star or other and thus the sky would be as bright as the surface of the sun. this is known as Olber’s paradox: http://en.wikipedia.org/wiki/Olbers%27_paradox
Kudzu
The high entropy disordered state of the primordial pre solar system dust cloud collapsed due to a shock from a nearby supernova (as I recall reading about). After the initial perturbation, gravity did the rest to collapse the cloud and create a low entropy more ordered system of revolving and rotating relatively compact bodies.
The radiation emitted by the collapsed system doesn’t negate the observation that it was the action of gravity that resulted in a lower entropy system. Yes, the radiation carries off the difference in entropy, but that radiation is not lost in an infinite universe, it can be reused in ways that can create low entropy systems. The portion of radiation our biosphere receives from our sun powers all kinds of neat chemical and biological responses that create lower entropy states.
Since we don’t really know what causes gravity (except to say most likely it is the result of an induced imbalance of a microcosm of impinging bodies that have inertia) we should keep an open mind that maybe that radiation has something to do with the phenomenon of gravitation.
(Saying that gravity is the result of space-time curvature and that space-time curvature is caused by mass doesn’t really explain gravity, especially since the equivalence principle shows us that we don’t need a massive body to produce the gravitational space-time curvature effect; just a rocket engine will do or other kind of acceleration that isn’t of the free-fall type.)
Your third paragraph seems to imply that I said or implied that the solar system could be or should be eternal. Structured systems in the universe are not eternal in any realistic model. What is eternal in an infinite universe is matter in motion.
Your fourth paragraph refers to Olber’s Paradox. That would be a problem to explain but isn’t because luminous stars do not have an infinite lifetime. For more details about that see the front page of my website critiquing the supporting assumptions for the Big Bang theory. Clicking on my underlined name at the beginning of this post will take you to my website.
While it is true that radiation can power a system and allow it to reduce its entropy, it can never reduce that system’s entropy by more than th entropy *gain* in creating that radiation.
Our planet gets energy from the sun’s radiation, and emits lower energy, higher entropy infared and radio radiation. This can be used by a far smaller number of processes which mostly emit very low energy radio waves.
The energy from our collapsing solar system and indeed our sun currently is high entropy in two ways. firstly a lot of it is low energy and secondly it is very dilute. This is why it is unlikely there is life on gas giant moons (Those not being heated by a totally different process, tidal forces.); there simply is not enough energy density to reduce the local entropy.
Indeed it is very hard to think of what use radiation emitted by our solar system could be, we receive the radiation from billions of similar systems, or stars, and starlight, even that of stars the human eye can see, is very faint.
My third paragraph applies to all physical systems, the solar system is just an example. If we move up to the universe as a whole, we have yet to observe any process that inserts energy into a system. The mass in our galaxy is slowly but surely falling into its center, the stars are converting mass into dilute radiation that spreads into the intergalactic void and in general things are running down. There is no place in the universe I am aware of where ‘new’ universe is being created.
Matter (If you count all particles as matter.) in motion is indeed eternal (Photons for one can never not be in motion.) but this is different from saying that that motion can do useful work. Matter at absolute zero still moves to some degree, but cannot ever reduce the entropy of a system. (Though it makes a great heat sink.)
The fact that stars do not have an infinite lifetime is not really a problem for the paradox; if the universe is infinitely old than an infinite number of them have existed in any given area, emitting an infinite amount of energy. If I light my house all night with one lightbuld, or replace the bulb every hour, I still use the same amount of energy. I do however admit that some of your sources make some far better arguments, though I am not convinced by them.
I am curious as to why you believe only material objects can expand. If you have a situation where any two objects move apart at speeds relative to the distance between them then what you have is equivalent to expanding space. (It may well be a property of the objects, but it is equivalent.) Of course the error may be in thinking of empty space as nothing; for ‘nothing’ it sure has a lot of properties.
Frankly I am not a fan of inflation, the theory if shot full of holes. But I have yet to see a compelling argument for the infinite universe either. The wonderful thing about science however is that you simply cannot hide the truth. Eventually those who back a wrong theory will become the science denying ideologues like those who clutter climate change and the age of the earth.
What I would like to see is a black dwarf, if anything would prove conclusively our universe is older than we think it would be that. (Or of course a burned out brown dwarf, likely to be much, much more common.)
My apologies in that last post. I didn’t mean to completely paste Kudzu’s statement ahead of mine. I was using his full statement for reference in iPad Notes while I was composing my reply and when I cut and pasted, Kudzu’s statement went along with the ride. So my name appears on top of his statement followed by my statement.
Vincent Sauvé
By now i think that most readers of this website came to the conclusion that the most fundamental basic level of cosmic existence is not fields nor particles but pure activity , rules , principles and equations……..information.
All materialized entities are in constant flux and change , the only stable permanent entity is information……this is really amazing…..it is wonder of wonders as NO physical mechanism of any degree can in principle generate the information on which itself is built……..infinite regress of the third kind..
Happy new year.
aa. sh.:
I like your statement. But there only is an issue if you don’t think the universe is infinite. Personally, I don’t buy the Big Bang beginning to the universe idea or any idea of cosmic creation and therefore have no conflict with infinite regression. I’m not sure what you mean by the third kind.
Also, let’s keep in mind information must have a material foundation and oftentimes information doesn’t reach to the level of consciousness until a conscious creature discovers it.
I personally find the concept of information slightly dubious and have quite a few questions that need answering before I will accept it. The biggest obstacle for me to saying anything was ‘the most basic level’ of anything is whether it truly is, or whether we humans just say it is.
Kundzu, you may be correct.
“Nothing” have special meaning. It is not “0”. It means, you have belief or disbelief it is the same. But mathematically, (nothing)^2 is belief ?- sorry my opinion.
So the physical effect(the quantum action) is phenomenological ?
In mathematical models some constants are used as steroids to simulate “quantum action” ?
I am not entirely sure I understand what it is you are asking. However you are right in stating that not believing in something is different from believing something is wrong.
Thank you Kudzu,
Two photons = (photon)^2 = feel mass inside a closed system.
Also true for (nothing)^2 = feel mass inside a closed system – because Higgs “vev” going and coming out of closed systems.
What make them contained in a closed system ?
It is simple in nucleons contained in a closed system – if we split them by external energy, they release enormous binding energy calculated by E = mc^2.
For going and coming out of a closed system need enormous energy, even for spin zero ?
Can we say, E(dark energy) = m (nothing)^2 ?
So anti gravity(dark energy) is inversely proportional to non zero “nothing” (Higgs vev) ?
So we could feel the mass or physical effect(the quantum action) ?
The feeling of mass = nothing^2 – is a belief(consciousness). This belief has been an intrinsic or quantized genetic code – preserved by Quantum entanglement – so it is same in different space time for different observers ?
How all quarks are locked away in hadrons?. Space expansion by dark energy keeping them appart?- because the “space between lattice sites” would fused at quantum gravity distance?. So there is Asymptotic freedom – The Isospin “I” and Spin could preserve angular momentum by change in locations at once.
If Planck’s constant h divided by R and by the speed of light c, the amount of energy in a little box(radius equal to R ) obey conservation law? – the particle will, on average, be speeding around with a momentum proportional to 1/R. The plank’s constant is the quantum action in QM. This “quantum action” will not function, if the “space between lattice sites” become occupied?
At the point of speeding “around” there is loss of kinetic energy(may be c = 0). Due to conservation law it again speeding to “c”. Actually it is c^2, 0^2 = c^2, here 0^2 ≠ 0 – means… the discretion between wave and particle is maintained even at quantum gravity distance – they could feel mass- may be because of Higgs field or dark energy?
The binding energy of quark-anti quark or confinement may be due to change in kinetic energy expressed by Bremsstrahlung(free-free radiation) – like Cherenkov radiation, another kind of braking radiation which only occurs in matter, not vacuum ?
Lattice QCD has already made successful contact with many experiments. For example the mass of the proton has been determined theoretically with an error of less than 2 percent. It works because it approximate continuum Quantum chromodynamics as the spacing between lattice sites which is reduced to zero- means, reducing a wave to particle.
The binding energy related to the residual strong force is used in nuclear power and nuclear weapons. But binding energy between quarks were confined. At high energy and short distance, it behave Asymptotic freedom because the discretion mentioned in Lattice QCD as “spacing between lattice sites” is reduced and particles could not feel mass- thus no attraction or repulsion- weak interaction. Less space for roaring around and zero speed??
Dr. STRASSLER :
What would happen if the strong force behaved as function of 1/r^2 ?
What would happen if free quarks were allowed ?
Dr. Strassler :
HAPPY NEW YEAR
TO Dr. STRASSLER ….URGENT :
There is something fishy in the sources about the strong force….
According to sources the S.F. lessens from infinity to constant value of attraction . among quarks then after crossing the hadron boundary it change sign to infinite repulsion then it change sign to short range attraction then it disappear !!!.
what a mess !!!!
The strong force between quarks is different than the strong force between hadrons. (Which is often called the nuclear force.) The situation is similar to the London forces between molecules, which arise from the electromagnetic force. These too are repulsive at short distances and attractive at longer ones.
The strong force is quite simple and tries to follow a simple 1/r^2 law, but the fact quarks and gluons feel the force complicates matters, resulting in quark confinement and other things.
The nuclear force is a ‘leftover’ force that remains after all quarks are locked away in hadrons and so behaves in a more complex manner.
Just a 1% change in the strength of the strong nuclear force at very short distance(where quantum gravity is important) can lead to a 10% change in R!
Like the electron mass, the mass of each quark is related to the quark’s Yukawa coupling (i.e., how strongly it interacts with the Higgs field) times the non-zero value of the Higgs field.
In a real nucleus, each nucleon is in multiple locations at once, spread throughout the nucleus. It is same for the quarks inside nucleons.
The interaction between a scalar field(Higgs vev) and a Dirac field(fermions) ,Through spontaneous symmetry breaking acquire mass.
The central part of the potential induced by pion(pseudoscalar mesons) exchange (preserves angular momentum by definition) depends on the spin and isospin channel. It is attractive for I(isospin) = 0, S(spin) = 1, I = 1, S = 0 ,but repulsive for the I = 0, S = 0 and I = 1, S = 1 channels.
Spin is polarisation, isospin is values related to the number of charge states.
So permanent attraction and permanent repulsion has been prevented by change in locations at once. This change occurs due to Higgs vev? – becaz , through spontaneous symmetry breaking Higgs non zero equilibrium goes abruptly to zero ?
Now some physicists say : the strong force change to repulsion at very short range , otherwise quarks would ” merge ( Dr. hugh ross ) , some others say it tends to attractive infinity ( Dr. m. strassler )……
I a lay person ; what should i believe ?
“” Solid “” proof is just a mirage……..
This is a very interesting issue indeed. As a layperson myself I find it simplest to go with ‘all forces go to infinity at real short distances’; even gravity, as weak as it is will become infinitely strong as two particles are bought closer together.
One of the things to keep in mind is that at the subatomic level particles don’t like being squashed together, the exclusion principle forces atoms to be hugely larger by keeping all of the electrons in different shells instead of all stuck in the smallest one. Quantum effects mean the shells cannot be infinitely tiny but have certain sizes and shapes. And of course as particles get closer together their position is better known, which means their speed becomes less certain (read: faster)
Of course the big issue here is the difference between the strong force itself (Between quarks.) and the nuclear force (Between protons and neutrons, a sort of ‘leftover’ strong force.) The two are not the same and are easily confused.
A purely attractive model of the nuclear force I like is the one-pion exchange potential (OPEP) model. It predicts roughly the size and behavior of nucleons and is a personal favorite model of mine.
Correct Mr aa, sh.,
when particles get closer together their position is better known, which means their speed becomes less faster.
Without mass no attraction, speed will not become less faster – “their position” will not be prominent.
To acquire mass Higgs vev is needed ?
I am curious about this, c is a very precise speed, we know it very exactly from measurement. This means that we know the speed of all photons all the time this exactly, without having to measure it. DOes this mean we can measure their position as much as we like and thus know both their speed and position as accurately as we like? I am sure there is a flaw in my reasoning somewhere.
Photon is massless, m = 0. When two photons turn around, the system feel mass- when c^2, m ≠ 0. So 0^2 = c^2 and 0 = c at the point of turning.
The physical datum here is, the speed of light c is the limit of comprehension – in which a mass could be created, otherwise it will escape all closed system – incomprehensible ?
Incomprehensible perhaps, I cannot follow your line of thinking. Could you explain it in smaller, simpler terms? Think of me as a Fox News reader.
This exactly what i am saying……. ( injecting some numbers……AS IF there is a physical datum )
And now they start to talk about ” inner life of quarks ” , and that top quarks should be composite …….putting aside the 10^500 worlds landscape …..
What is the limit of fancy worlds ?
This is why I never take a theory seriously until it is at least 20 years old or has solid proof. It is easy to talk and think, but much harder to *prove*
Thank you Mr.aa. sh,
I mean, not the physical datum or Physical information- as in “spreading of heat energy calculated by limits and functions in calculus- and in quantum entanglement relationships between apparently distinct(particle nature) or spatially separated particles(wave nature).
It is about injecting some constants and Numbers into scientific models and mutate the model as if there is physical datum exist.
√-1 = i is imaginary number.
i^2 = √-1 . √-1 = (√-1)^2 = 1 become a real number – eventhough Accuracy and precision is not guaranteed by even, real numbers – according to Bekenstein bound.
In modern mathematics, algebra has become so important that numbers will soon only have symbolic meaning.
https://fbcdn-sphotos-c-a.akamaihd.net/hphotos-ak-ash4/397600_506087442755478_910202478_n.jpg
P.S. :
To show how the real corrects the abstract , your final equation must be :
origin———-a————-t/2————-b
t/2-a=b-t/2
t = a+b
see what i mean
TO VEERAMOHAN :
Your proof proved a most crucial fact , that is : unless a theory is based on real physical datum , its math. could lead to nonsense …..
Look at your “” proof “” :
a – t/2 = b – t/2
as symbols you can cancel both of t/2 but this is nonsense since t/2 is the average of a+b …. it is the point of origin…
a———-t/2———b
so No. of units from t/2 to a = No. of units from b to t/2
it is by no means mean that a=b
this is the physical aspect of what otherwise would lead to mere nonsense.
I would like to present my final solution concerning constant :
“What is varied in Universe, what isn’t?”
http://vixra.org/abs/1212.0080
TO VEERAMOHAN :
You just proved that we can not trust any theory as by math. manipulations we can prove the impossible!!!
Indeed. It would be foolish to put complete trust in any theory, we can always be wrong. The sun may actually orbit the earth and all this time we got the wrong measurements by pure coincidence.
Of course if we went around not trusting anything our lives would be rather bleak and terrible. That’s why we have limited trust in various things, some more than others. I trust gravity will hold me down today as it did yesterday, I trust the various laws and processes making my computer do what it does will not suddenly change tomorrow, I even trust people to obey the traffic laws (But not nearly as much as I trust gravity.)
How much confidence we can put in a theory depends on the evidence for it, and no matter how elegant or simple or satisfying a theory is, what matters in the end is the proof.
Each morning, the sun rises in the east. If we say, it need great
Mathematics to predict this, and confine ordinary people to follow only these predictions by looking into TV boxes and clocks they sell inside a dark room- then, one day they will say, “Sun rises in north”- we have to believe.
This is what happened in financial world now!.
There is great gap between what nature does, and what humans theorize it. We believe the dedication of committed scientists- that is what happened in 18th, 19th centuries. Now many “undedicated” people mastered the present financial and monetary systems- so many bizarre theories with bizarre mathetical proofs.
We must look outside the windows or go out to look the sky for sunrise- not confine to TVs for sunrise videos.
Nature turned around many good intentions also. Scientific discoveries many times unfolded and conjured towards wars and civil conflicts.
There haven’t been any unexpected discoveries since the 1970s. Not one significant surprise. Not because the experimentalists are doing something wrong; rather, the theory is just too good – maddeningly, frustratingly good.
Not since the 1970s? I would suggest otherwise. The biggest one at the moment would be the ‘firewall’ problem with black holes, but I would also list the discovery of ‘lamarckian’ genetics and the fact that junk DNA has functions, the fact the universe’s rate of expansion is increasing and the remarkable chemistry of colloidal metals as things that threw scientists for a loop. Indeed given the last 40 years I shouldn’t think there was any branch of science that has escaped remarkable discoveries. The standard model has held up well, many theories do, but all around it the unbelievable has been happening.
Your other comments relate to experts and trust. In the end there are some matters where we just have to trust in others. No human alive knows how my computer works; some know how this program works, others know how the fan or the mouse is put together, but the whole thing is to complex, too big for any one person to need or even be able to know.
There are many things we teach but don’t prove, even the earth going around the sun, do you know how to *prove* it? How do we really know thermodynamics works or that TV programs are broadcast through the air from TV stations? In so many things we just assume what we are told because if we tested everything we would spend all our time reinventing the wheel and none of it doing anything new.
What’s the problem with the proof below?
https://fbcdn-sphotos-f-a.akamaihd.net/hphotos-ak-ash3/16567_504227789608110_1031794983_n.jpg
This was the tricks played by the quantum of action in quantum mechanics(Planck constant), Imaginary number, Euler’s totient function.
In quantum mechanics, the reverberation(and dissipation into nothing) of wave nature(frequency or energy), may create stress energy, but not making “quantum of action(physical effect)”. It has been created only by particle nature or field(stuff).
Physical effect is phenomenological?
Quantum gravity or gaviton, is not a field, but a action created by a field(may be Higgs particle)?
Rest mass has been not created by Higgs vev(but by gold stone bosons), was created by big bang temperature(after cooling)?. Higgs particle(h) only create graviton(quantum gravity)?. So change in “confinement scale” will weaken the frequency of Higgs non zero equilibrium and increase its wavelength- thus “a change” in known particle mass?.
Once again another great article, although I did smile that you felt the need to explain a centimeter is a bit more than 1/3 of an inch.
Interesting remark in fig 2. “how strong is the strong nuclear force at a distance scale where quantum gravity is important”.
So does this result really have something meaningful to say about physics at the quantum gravity scale, especially with all the unknown BSM physics lying in between. Perhaps I should be thinking the other way around, and had the experiment indicated the constants were changing, then the nature of those changes might have been revealing for quantum gravity scale physics.
Sorry for yesterday miscalculation:
e= (0,1e; e=e; e=100e ) vary 3 order(10^3 times) ;
Mel (10^-29;10^-28; 10^-26;) vary 3 order(10^3times) ;
alpha (0,001; 1/137; 10^41) ;
Try to calculate finish alpha :
(100)^2/(10^-27 x10^-10)=10^4/(10^-27×10^-10)=10^41;
sqrt(1836)=42.8
Conclusion: 1836 and 137 are not constants in history of the Universe
Mpr=10^-24g constant
1836/100=18.3
Thank you for this interesting article, Matt. Using astrophysical observations helps us to understand if the properties measured in experiments on Earth can be expected to be of “universal” nature (or at least over large distances and times).
I only have a few difficulties with the conclusion that if the ratio of electron and proton mass is measured to be constant, each one of the masses (or of the underlying processes giving reason to the mass) must be constant as well.
There are many examples in physics and engineering where a ratio of two properties is constant, but the properties themselves are not constant at all. For example, I am thinking of the Reynolds number in fluid dynamics, where two different experiments may have very different properties (for example, flow of water compared to flow of air), but with a proper arrangement, both flows may show more or less the same characteristics, and have the same ratio of contributing forces.
You take this possiblility in count: “Of course, it is possible that several of these quantities are varying, and just by chance all the variation cancels out of the electron mass to proton mass ratio.” However, “by chance” is not the only way how the variations may cancel out. Another, physically more important case would be that there were an underlying, probably more fundamental physical process that acts on both the numerator and the denominator of the ratio.
Okay, for the moment there may be no hint for such a process. It is only that the conclusion from the constant ratio to the constance of both the electron and proton masses seems to be a bit strong, if not supported by other, independent reasoning and/or measurements.
If constants are changeable –oxymoron !!??– and science proved they are constant , then what mechanism keeps their constancy ??
Thank you very much for this nice article Professor Strassler!
Wonder of wonders ; if every thing is in flux on the most fundamental realm then whence over-all constancy comes in the classical realm ?
Then MATT. ; what physical mechanism / cause directs the strong force to act in that most unusual way without which there would be no protons , atoms , ……..us. ?
This question has a very simple answer which is also not entirely satisfying.
In a a large part the predictability and order we see in the classical realm is just one of averages. All the molecules in a glass of water are constantly moving and colliding, but on overage their velocity is zero, so the water just sits there. So it is that the small chaos mostly cancels out, though it can still be powerful. (Air pressure is from air molecules hitting you at high speed from all directions. you can ignore it, but you can see its power when it is absent: http://www.youtube.com/watch?v=p3b9pK-O6cE )
However this doesn’t explain why our classical world isn’t quantum, why we can’t be in two places at once or tunnel through solid objects. That is far harder to answer.
Hi Matt. , for me this article is your magnum opus……really.
I read that the strong force change sign to repulsion at very short distance , is this correct ?
Excellent article professor Strassler,
the ratio of the electron mass to the proton mass is not changing even in half way of universe- but how we first measure one of its mass in earth?
The Yukawa couplings are hypothesized to have small values at the extremely high energy scale of grand unification, 1015 GeV. They increase in value at lower energy scales, at which the quark masses are generated by the Higgs(when space expansion and cooling take place).
The mass of the proton is set by a curious and crucial feature of the strong nuclear force. The force will stop decreasing at “confinement scale(quasi-infrared fixed point- corrected by QCD corrections?)”. How it will be a constant?
To fix the gluons inside a little sphere with radius about equal to the confinement scale needs Planck’s constant h!
The change in “R” may affected by further expansion of space due to quantum gravity?
Quantum gravity evolved from classical mechanics, newtonian gravity, and general relativity. The mathematical evolution of classical mechanics into quantum mechanics have incompatibility with general relativity in context with QFT in curved spacetime(gravity).
Graviton represent quantum gravity. It is not a particle of an implied field, but constantly created by “stress mass(energy)”?
The presence of mass, energy, and momentum (collectively quantified as mass-energy density or stress-energy) resulted in a bending of this space-time coordinate system. Gravity, therefore, was movement along the “simplest” or “least-energetic” route along this curved space-time.
Gravity is feeble because of planck constant “G”. But “g” is created by collective “stress mass(may be by Higgs particles)” along the borders of a closed systems like atoms, quarks..ect?
Higgs vev give mass to quarks and electrons but not affected by electromagnectic and strong forces- but have Yukawa couplings. But due to
Spontaneous symmetry breaking towards “least-energetic” level, Higgs vev go abruptly to zero value outside all closed system(like atoms) upto transcendental Higgs field – and in non zero gives mass?
“G” is only a proportionality constant, is a planck unit- related to general relativity and newtonian gravity.
/…We see the question is not, “Why is gravity so feeble?” but rather, “Why is the proton’s mass so small?” For in Natural (Planck) Units, the strength of gravity simply is what it is, a primary quantity, while the proton’s mass is the tiny number [1/(13 quintillion)]…/– Frank Wilczek.
Is there any connection between frequency of a particle and its “stress mass”- so that we can call, “frequently soaked in Higgs field” – more frequently more mass?
The electron-proton mass ratio can be measured in many ways, for example seeing how much either particle’s path curves in a magnetic field. The method used in the paper here relied (very basically) on the color of light a certain molecule emits which is very precisely determined by that ratio.
Enlightening, thank you Mr.Kudzu,
in 1896, J. J. Thomson estimated both the charge e and the mass m, of electron, finding that cathode ray particles, which he called “corpuscles,” had perhaps one thousandth of the mass of the least massive ion known: hydrogen.
Imaginary numbers are always involved in the history of deriving electron, proton masses from Lorentz force law and Newton’s second law of motion – later from classical mechanics, former involve probabilistic abstracts(near speed c) like Tensor field.
Classical mechanical intuition says the ratio of the electron mass to the proton mass is not changing at local symmetry.
The effect of expansion of space may have been cancelled by quantum gravity at the level of strong force- which keep proton mass constant and thus electron mass- but this is not the case for Higgs particle- which behave as graviton at its non zero equilibrium?
The imaginary number is a fine and wonderful resource of the human spirit, almost an amphibian between being and not being. (Gottfried W Leibniz).
I’ve read a few times about changes in fundamental constants, and the thought I always have is: changes depending on what?
the only way I can conceptualise it would that there would have to be some kind of field, and the local value of that filed affected a “fundamental” constant in some way. But then (as you’ve taught us) if you have a field, you need one or more particles, right? And how does the value of that field evolve, and why?
Now that I put it like this, I’m reminded of dark energy. We’re told it’s some kind of field which (in some models) is changing in strength over time. why? and time measured in relation to what?
I apologise for such a rambling comment/question 😉
Excellent article indeed! We should really be grateful to Prof. Strassler for explaining all these things to us. However, the interpretation of the cosmological redshift as a Doppler effect(albeit relativistic) is not favored by cosmologists. (see, e.g, Chapter 1.2 of Steven Weinberg’s treatise “Cosmology”).
Albattani,
Weinberg and most other cosmologists favor the interpretation of the cosmological redshift as due to the expansion of the spacetime metric, which is very similar to a Doppler redshift effect. Edwin Hubble, some others and myself did and do not favor that interpretation. For us it is more reasonable to view cosmological redshifts as distance indicators only plus some unknown cause that reduces the rate of arrival of individual photons and their energy. For further details click on my name here.
Very nice article, thanks!
Matt, if you’re interested in an actual model in which the strongest bound comes from measuring the electron-proton mass ratio in quasar spectra, look at my paper with Dani Hernandez at arXiv:1101.5695. Alas, the quasar reported in the Amsterdam-Bonn paper is the same one for which we cited previous bounds (which were similar). One really needs a third radio quasar to improve our bound, as noted there.
I submit yesterday article just for this topic
http://vixra.org/abs/0907.0012
The universe is evolving. That is, many things are changing. The gravitational constant is obviously changing (this is a part of reason for dark matter). In practical, all changing systems have, at least, one thing is not changing. In fact, ontologically, with one “absoluteness”, everything else is allowed to change, and the essence of the system will not be changed. This universe needs only one absolute, Alpha (fine structure constant) could be a good candidate.
Alpha is almost not changing. It, in fact, can still change slightly. The only absolute that this universe needs is an unchanging “zero”, the cosmological constant. Anyway, with a not changing much Alpha, all other constants are very much stay put. All other explanations are good details, not important ontologically.
You make these statements as though they are statements of fact. It is necessary for me to point out that these are your own personal opinions, not shared by the physics community.
Huh, why should the gravitational constant (meaning G ?) be changing? What are the ideas behind this ? Is G not together with h and c in a group of fundamental constants that should really not change ?
However, I predict that some other fundamental constants will change soon ——- abruptly —– next Frideay ….
😛 😀 😉
Lenny Susskind has explained that in QG one has G = l_p^2 (= g^2*l_s^2) …
Aah, so I can change the g to change the G … ;-P
I’ll try this on Friday 🙂
the Universe (CGS units)
Vary: G,c,e,alpha (fine-structure constant),Mel
Start;Today;Finish.
G (10^22; 10^-8; 10^-28) G vary +- 20 order magnitude from Today (FT) c(10^30; 10^10; 10^-10)] c vary +-20 order magnitude(FT)
e=0,1; e=e; e=144 ;
prediction of George Gamow, Phys. Rev. Lett. 19, 759 (1967). e ~ t.
alpha (0,001; 1/137; 10^10-39)
Mel (10^-29;10^-28; 10^-25;) 2 order(144) times
Finish:(c x G)/h =(10^-10 x 10^-28)/10^-27=10^-11 sm x sec^-2 x g^-2
Constants: h, Mpl, Mpr,Time of the Cycle of the Universe.
h=10^-27 gsm^2/sec; Mpr=10-24g; Mpl=10^-5g ; T=144 10^9years = 10^18sec
h=g x sm^2/sec is 2-Dimensional quanta of the Universe wrapped in 3-Dimensional Space.
Hint to Holographic universe…???
Just something that I have always wanted to get straight in my head. The strong force is unlike the say, electromagnetic force in not eventually becoming zero between to particles as the distance between them goes to infinity. Is this due to the strength of the strong force itself, or due to some property of the strong force. That is, if the electromagnetic force were as strong as the strong force, would it likewise not fall to zero as two charged particles were moved apart?
Otherwise, this is a brilliant little summary of an interesting issue.
The major difference between the strong force and electromagnetism is that the strong force feels itself. That is, the photon is not electrically charged, but the gluon does carry color. So the answer is, the weird distance properties of the strong force would not carry over if the electromagnetic coupling constant were huge.
I feel like slapping myself; that answer is so obvious and simple that I should have seen it a mile off. Thanks for taking the time to show me the obvious.
You said that the strength of the strong force is proportional to ℏ/c, implying that the proton mass is dependent on ℏ and c. I assume that the electron mass also depend on ℏ and c in some way, probably through the Yukawa coupling. Is the overall mass ratio dependent on ℏ and c, so that this result would be sensitive to any inconstancy of ℏ or c?
I’m a little confused by figure 1. The purple line represents the strong nuclear force normalized to its own strength at r > R. Shouldn’t it be equal to 1 beyond that point? Or did you mean that its normalized to the force at r>>R?
Yes fascinating article – maybe the distance measured @ 1/2 universe gap was far too small to show any small variation, and indeed maybe the understood 13.7B ly’s dia is also a minute distance. But sure huge in terms of man’s yardstick Kms very impressive. Going to re read your strong nuclear force behaviour sounds interesting. Presumably, if they had found a variation in methanal electron masses would imply the universe is elastic. I don’t think nature would permit that ( at least no in our universe ) – but worth checking out! If so would make the task of physics like a horse race you would never know which would win. At least in the current scenario the favourite is always champion.
I am afraid I don’t see any connection with elasticity of the universe.
Great Article I’d been waiting for one explaining the “missing” proton mass.
One thing I don’t understand – although this is probably outside the scope of this article – I thought that distance at an astronomical level was hard to determine and one of the main ways of doing this was through the colour of supernovas or similar energetic astronomic events. But if colour told us the distance/time and these detailed experiments confirm that colour doesn’t change with time/distance then I don’t understand how you can calibrate out that uncertainty.
I’m sure this has been accounted for somehow but I don’t know how you can determine distance without hitting this problem.
Good question. There’s quite a bit to say here, but a really short answer, relevant for today’s article, is this: colors do shift, through the (relativistic) Doppler effect, just because the universe is expanding and the galaxy containing the methanol is moving relative to us. This is called “redshift”. But redshift, being just due to motion, affects all colors in the same, predictable way, so it doesn’t change the relationship between two colors. So what is actually done is to compare two colors, and that comparison can be done both for the light (or radio waves, or electromagnetic radiation of any other wavelength) coming from space and the light observed in a scientist’s lab.