Saturday, July 17, 2021

What’s the Fifth Force?

[This is a transcript of the video embedded below.]


Physicists may have found a fifth force. Uh, that sounds exciting. And since it sounds so exciting, you see it in headlines frequently, so frequently you probably wonder how many of these fifth forces there are. And what’s a fifth force anyway? Could it really exist? If it exists, is it good for anything? That’s what we’ll talk about today.

Before we can talk about the fifth force, we have to briefly talk about the first four forces. To our best current knowledge, all matter in the universe is made of 25 particles. Physicists collect them in the “standard model” that’s kind of like the periodic table for subatomic particles. These 25 particles are held together by four forces. That’s 1) gravity, apples falling down and all that, 2) the electromagnetic force, that’s a combination of the electric and magnetic force which really belong together, 3) the strong nuclear force that holds together atomic nuclei against the electromagnetic force, and 4) the weak nuclear force that’s responsible for nuclear decay.

All other forces that we know, for example the van-der Waals force that keeps atoms together in molecules, friction forces, muscle forces, these are all emergent forces. That they are emergent means that they derive from those four fundamental forces. And that those forces are fundamental means they are not emergent – they cannot be derived from anything else. Or at least we don’t presently know anything simpler that they could be derived from.

Now, if you say that gravity is a force in the wrong company, someone might point out that Einstein taught us gravity is not a force. Yes, that guy again. According to Einstein, gravity is the effect of a curved space-time. Looks like a force, but isn’t one. Indeed, that’s the reason why physicists, if they want to be very precise, will not speak of four fundamental *forces, but of four fundamental interactions. But in reality, I hear them talk about the gravitational force all the time, so I would say if you want to call gravity a force, please go ahead, we all know what you mean.

As you can tell already from that, what physicists call a force doesn’t have a very precise definition. For example, the three forces besides gravity – the electromagnetic and the strong and weak nuclear force – are similar in that we know they are mediated by exchange particles. So that means if there is a force between two particles, like, say, a positively charged proton and a negatively charged electron, then you can understand that force as the exchange of another particle between them. For the case of electromagnetism, that exchange particle is the photon, the quantum of light. For the strong and weak nuclear force, we also have exchange particles. For the strong nuclear force, those are called “gluons” because they “glue” quarks together, and for the weak nuclear force, these are called the Z and W bosons.

Gravity, again, is the odd one out. We believe it has an exchange particle – that particle is called the “graviton” – but we don’t know whether that particle actually exists, it’s never been measured. And on the other hand, we have an exchange particle to which we don’t associate a force, and that’s the Higgs-boson. The Higgs-boson is the particle that gives masses to the other particles. It does that by interacting with those particles, and it acts pretty much like a force carrier. Indeed, some physicists *do* call the Higgs-exchange a force. But most of them don’t.

The reason is that the exchange particles of electromagnetism, the strong and weak nuclear force, and even gravity, hypothetically, all come out of symmetry requirements. The Higgs-boson doesn’t. That may not be a particularly good reason to not call it a force carrier, but that’s the common terminology. Four fundamental forces, among them is gravity, which isn’t a force, but not the Higgs-exchange, which is a force. Yes, it’s confusing.

So what’s with that fifth force? The fifth force is a hypothetical, new, fundamental force for which we don’t yet have evidence. It we found it, it would be the biggest physics news in 100 years. That’s why it frequently makes headlines. There isn’t one particular fifth force, but there’s a large number of “fifth” forces that physicists have invented and that they’re now looking for.

We know that if a fifth force exists it’s difficult to observe, because otherwise we’d already have noticed it. This means, this force either only becomes noticeable at very long distances – so you’d see it in cosmology or astrophysics – or it become noticeable at very short distances, and it’s hidden somewhere in the realm of particle physics.

For example, the anomaly in the muon g-2, could be a sign for a new force carrier, so it could be a fifth force. Or maybe not. There is also a supposed anomaly in some nuclear transitions, which could be mediated by a new particle, called X17, which would carry a fifth force. Or maybe not. Neither of these anomalies are very compelling evidence, the most likely explanation in both cases is some difficult nuclear physics.

The most plausible case for a fifth force, I think, comes from the observations we usually attribute to dark matter. Astrophysicists introduce dark matter because they do see a force that’s acting on normal matter. The currently most widely accepted hypothesis for this observation is that this force is just gravity, so an old force, if you wish, but that instead there is some new type of matter. That doesn’t fit very well with all observations, so it could be instead that it’s actually not just gravity, but indeed a new force, and that would be a fifth force. Dark energy, too, is sometimes attributed to a fifth force. But this isn’t really necessary to explain observations, at least not at the moment.

If we found evidence for such a new force, could we do anything with it? Almost certainly not, at least not in the foreseeable future. The reason is, if such forces exist, their effects must be very very small otherwise we’d have noticed them earlier. So, you most definitely can’t use it for Yogic flying, or to pin your enemies to the wall. However, who knows, if we do find a new force, maybe one day we’ll figure out something to do with it. It’s definitely worth looking for.

So, if you read headlines about a fifth force, that just means there’s some anomalous observation which can be explained by a new fundamental interaction, most often a new particle. It’s a catchy phrase, but really quite vague and not very informative.

106 comments:

  1. @Dr. Hossenfelder:

    Awesome video!
    One commenter on YouTube asked a question I'd like to put to you, 'What is the speed of gravity?'

    (Just kidding, I'll see what the Internet can tell me.) ;-)

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    1. I think that the answer that you are looking for is C, just like you, but without the Thompson part.

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    2. I had thought of changing my user name but decided that I like being The Speed of Light. :)

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    3. The g – 2 issue I think is a matter of not computing QED corrections correctly with masses of fermions, in particular the muon. There are complicated matters of gauge redundancies that can multiply the contributions of mass. Developments such as BCFW recursion and others put gauge field theory on a topological basis that removes a lot of this gauge redundancy.

      The X-17 is somewhat interesting, but it is not clear to me that this is free from some complexities of many-body SU(2) gauge theory of nuclear binding. After all, atomic physics that is a U(1) gauge theory of a many-body quantum system has continued problems and unknowns.

      Dark matter is a possibility. Even in the ΛCDM theory these particles must have some sort of interaction, at least with each other. This may then in some unification scheme, GUT etc, have some connection to ordinary matter. Whether the long range force that is some correction on gravity exists remains to be seen.

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    4. & I thought C. stood for cyborg [ But I have to admit: I like it better this way. ]° . ^.^ , °[ & No! I will not write anything on the subject of the speed of light or Johannes Diderik' powers... yet. ]

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    5. But why is the speed of gravity the same as the speed of light?

      Is there a same underlying mechanism of how these different waves move?

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    6. Hi Martien,
      There are articles answering the question of why they are the same online, I had a quick look.
      A commenter on YouTube said that the speeds are slightly different with light being faster, but this different is so slight as to be barely detectable.

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    7. @Martien, if I recall a E&M physics course from many years ago, Einstein had a proof that it didn't make sense for anything to move faster than the speed of light, which made sense to me too at the time, but I have forgotten the details. It was part of his Special Theory of Relativity.

      That doesn't explain why gravity couldn't move more slowly than c, but there might be a round-about reason in that the graviton (if it exists) should be massless (so as not to be self-interacting), and massless particles have no inertial barrier to prevent them from moving at the speed of light.

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    8. Massless things, such as electromagnetic waves or gravitational radiation exist on what we call a null geodesic. These are spacetime paths that have no distance in spacetime, are invariant and on a spatial measure move at the speed of light.

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    9. Martien, it's not necessarily that the speed of gravity equals the speed of light, but that c is the maximum speed of *information*, and given no obstruction, why *wouldn't* gravity waves move at that speed?

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    11. The "speed of gravity" is the same as that of light. I am scare-quoting this because we don't normally talk about propagating modes when we talk about gravity. Why is the speed the same? Well, that's just how it is. I don't know why people keep asking these questions. If you want a particle-physics answer it's because both photons and gravitons are massless, though of course we've never actually measured a graviton, so we actually talk about the thing that would be the mass term if gravity was quantized and had a graviton.

      In any case, you can just take Einstein's Field Equations, linearize them, and read off the speed.

      As to someone in a YouTube comment who claimed that light is faster, well, don't believe everything you read in YouTube comments.

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    12. mmm... I understand the speed of gravity is a result from maths and a well tested and confirmed model (general relativity), and maybe I should stop asking further questions.

      Long time ago in school I learned that an electromagnetic wave propagates because of oscillating magnetic and electric fields. One oscillation leads to the next, with some time delay because of the permeability of the vacuum for magnetic fields and there was another term like that for the electric fields. With these these terms one can calculate the speed of light. So I imagined that there is a kind of 'resistance' in a vacuum which limits the max speed of light. (So being without mass does not lead to infinite speed.)

      Maybe this is a simplification or a wrong or incomplete (even childish) picture. But it made me wonder whether there is a parallel type of mechanism with gravity. That still is not clear, except the explanation that general relativity would otherwise collapse.

      I can live with a world where different models apply to parts of reality only, and have long learned long ago that it is wise to know these 'model borders' and not to try to bring too many parts of reality under one model. (That was in my job as management trainer, I am retired now.)
      And the the speed of light for gravitational waves as a kind of dogma (at least for the time being).

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    13. What strikes me as well that an electromagnetic wave is moving in apace-time (although at speed c is looks different), while with gravity waves space itself is moving... at least that is how I interprete LIGO etc.

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    14. Ripples in space, I mean

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    15. @Dr. Hossenfelder:

      I don't believe every YouTube comment I read; there is plenty of weirdness and crack-pottery in the comments sections of your videos, the original comment I paraphrased at least seemed factual.

      My original comment was meant as a joke that seemed funnier when I made it sorry. I will often look up something that's a more simple question myself but the commentariat can have information from different angles, which is helpful.

      About questions people ask and why: On my part, I am trying to think in a way I hadn't much learned how to yet. I'm getting better at putting things together to ask some useful questions but I usually come up with questions that I can't tell if they make sense to ask so I don't expect they'll always get answered.

      @ Others:

      So it seems there's the short, relatively simple explanations then the 'well, actually' descriptions and then there's the esoteric answers full of equations and surnames. :)

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  2. how long in time do we need to wait for resolution on x17? i heard of x17 couple years ago and it is now july 2021

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    1. Here is an example that might re-calibrate your expectations. I read, probably on Wikipedia, that archeological evidence of modern human bone structure goes back about 200,000 years; and archeological evidence of the wheel and axle goes back about 6000 years. Now maybe we don't look as hard for wheels as bones, so I'll be generous and say it took us about 100,000 years of rolling logs to develop the wheel. Of course once you have a concept like that, uses multiply: chariots, pottery wheels, capstans, pulleys, gears, watermills, wind mills, computer hard drives ... but if its something new you haven't even seen before, not a derivative of existing concepts, how long "should" it take? Depends on how many people are working on it, for how long, just like everything else. There are a lot more ways that don't work than do, and so you try most of those first, as I see it. (In whatever spare time you have from dealing with other problems.)

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    2. The lack of follow on may be an indicator this hypothesis is not working.

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  3. . . . all taking place in the quantiferous ether.

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  4. What's about "time" or the "expansion of space", can't these characteristics of spacetime also considered as own natural force?

    And what about consciousness? Is it an own force or a state of condition of electromagnetism?

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    2. Pst, Jonathan...
      we all feel that way.
      In any case, me just like you...
      Every Saturday large parts of my brain simply switch over & a film is running that has little to do with the rest of reality...
      Sabine then only speaks to me & what she has to say is to be interpreted over so many semantic levels that I could actually be busy for the rest of the week...
      If it weren't for those strange other worlds that I unfortunately still have to take care of. ^.^ ,
      So if you feel compelled to apologize (8 times again, clever shit: at least in German, by the way, it's better to ask for forgiveness 8), then that only indicates that you are aware that the worlds we wander through together, unfortunately are quite far apart...
      Fortunately, distances seem to shrink the greater the distance from which they are viewed.

      Best regards,
      muck(8)

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    3. @Jonathan & muck:

      I tune in to 'Science without the Gobbledygook' like I used to watch favourite shows on television so I can jump into the YouTube comments after for a couple of hours, it's fun. I think finding this channel/blog was a bit of a game-changer for my thinking.

      Props to Dr Hossenfelder and her videographer for great content.

      I think Dr. Hossenfelder lets things chug along by themselves a fair bit here, so unless we manage to derail the blog somehow, we're okay. I figured if I'm being ignored then what I've said is a 'not even wrong'-level of incorrect, so I'm not worth the effort of responding to. If I say something worthwhile (or particularly stupid), the commentariat will catch it/ a certain commenter will just act like they know what they're on about to try to correct me, but whatever.

      I do find it noteworthy that people believe we're all interconnected, and that there are persistent, consistent belief patterns for deities, spiritual beings, ancestors, etc. that affect the world and communicate with people, and all the other ideas of other realms overlaying or seperate to ours that can be breached. I want to know why and where these all these beliefs and ideas all come from, and why we have them. I used to believe such a force/forces could exist, I don't much now but I'm not entirely unconvinced.

      I've copped crap here for saying I believe dreams can contain information relevant to the present and future events and situations, and I still don't entirely disbelieve that either. Maybe future advances in computing, physics, biology and neuroscience will show us *why* we think this way, and even reveal these phenomena. Even if it's all in our minds, I want to find out.

      P.S. My best friend told me I've been recruited into his cyborg army, so we're planning how to weaponise my pacemaker. :D

      Have a good one.

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    5. Many thanks to both of you.
      I'm glad you give me the feeling to be understood & wish you the best of all worlds & x~tesions (8)

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  6. A small quibble if you do not mind. I know the number of fundamental particles is not important and it depends upon how you count. I have heard the number 18 counting gluon as 1 particle and 25 if you count 8 gluons. On the other hand if you count antiparticles and still consider gluons as their own antiparticles then I come up with 38!!

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  7. The fifth force? Clearly, you are referring foundationally to the work of Prof Siniski formerly of the University of Warsaw. Let's be clear here, until the terminology is not agreed for concerning the zero-point/nulll/vacuum energy then we are left in the skotos (ignorance) of 'dark energy' from cosmology. DCN

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  8. 5th Force? How about the Force of Intelligence?

    his was propose by Wissner-Gross: F = T ∇ Sτ. It is a force that acts so to maximise future freedom of action. Intelligence is a physical process that maximises future freedom of action and avoids constraints in its own future. This allows for the building of complex systems and acts as an anti-entropy principle — making cosmology much more comprehensible.

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  9. The B meson anomaly is one of many weak force anomalies that might indicate the existence of new physics beyond the Standard Model.

    Under the Standard Model—the theory that describes elementary particles and the forces they obey, minus gravity—leptons such as electrons and muons are identical except for their mass. So B mesons should decay to a kaon and two muons at the same rate at which they decay to a kaon and two electrons. Yet LHCb is seeing a difference in this rare beauty decay: B mesons seem to decay to muons 15 percent less often than they do to electrons.

    This anomaly might indicate the existence of a new force carrying a boson that expresses the existence of a fifth force of nature. A popular theory that fits into my EVO theory of dark matter is the Leptoquark.

    Leptoquarks (LQs) are hypothetical particles that would interact with quarks and leptons. Leptoquarks are color-triplet bosons that carry both lepton and baryon numbers. Their other quantum numbers, like spin, (fractional) electric charge and weak isospin vary among theories.

    I do not view the Leptoquark as a particle but instead as a modified bubble of vacuum energy whose Higgs field equivalent being the same as existed in the era just after the big bang when the forces of nature were united.

    These modified vacuum derived Leptoquark like fields emerge in Grand unification theories; for example, in the Georgi–Glashow SU(5) model, they are called X and Y bosons.

    As dark matter, these superconductive based EVOs are usually dormant but may be excited through the infusion of free electrons and photons. The grand unified force carriers: X and Y bosons are then produced and have infinite range.

    These are dark photons that are not detectable or reproducible by the LHC since the Higgs field that the LHC operates under is not subject to the Grand unification level Higgs field that the EVO operates under. Only the weak force effects will show the effects of the dark photons.

    This Higgs field vacuum energy mismatch may be the reason why the X17 dark photon is not detectable during the The Atomki group's beryllium-8 decay experiments.

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  10. So, would this have to do with the unit of time that Bohm discussed with Einstein, where the Lagrangian density of the field theory would be calculated from the 'particle' selecting one Bohmian trajectory after another, according to the Born rule?

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  11. There was an article in CERN Courier (2 May 2019) entitled: “The flavour of new physics”. This article suggested two possible new force particles, though not at five sigma significance. I wrote an amateur paper in July 2019 showing the possible properties of these particles using my preon model.

    The idea lay in alterative routes in the decay of the bottom quark. The standard decay path is: bottom quark ---> charm quark + tau lepton + antineutrino where the charm is produced first, and a W boson is the force boson used, but not surviving the interaction.

    If this decay were possibly to happen in a different order: bottom quark ---> tau lepton + charm quark + antineutrino, then the force boson would be a leptoquark boson rather than the W boson. I showed that the leptoquark used in this particular possibility would have the properties:
    electric charge = +2/3
    spin = 0
    weak isospin = +0.5
    colour charge = red or green or blue.

    This was possible to find using the preon model as preons are supposed to be smaller elements of elementary particles. The original decay is run in this calculation in terms of the smaller preon elements and then rearranged into elementary particles to make the existing particles with the W boson's preons being rearranged to contribute to the structure of the leptoquark.

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  12. Perhaps we should ask Professor Doctor Famous.
    I hear that he has discovered a new force.

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  14. It seems to me to be worth mentioning that, just as there are interactions that are not forces, like gravity, there's also something that could be called a force but not an interaction! Namely, the exchange interaction, which is not an interaction at all, and yet results in what from a classical point of view a very important force; it's what causes the classical normal force, it's why you don't fall through the floor! So "force" and "interaction" are even more disconnected than you say...

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  15. If the speed of light and the speed of gravity are the same its probably because the speed of light is the maximum speed at which change can spread through spacetime. That they are the same is an important clue to the nature of reality. Although how to interpret that clue, I don't know.

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    1. Hi Steve, that they are the same seems to me that the Universe is a container of some sort within which the matter etc. that radiation, waves, particles, what-have-you travel through and interact with is somehow held. There's no obvious reason for me to think that though.

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    2. Hi C., ...
      I can think of a reason.
      The speed at which gravity spreads has an impact on the universe precisely when mass is added to or removed from the universe.





      PS: but I also think: "what have you" is the even more significant phrase than "that guy again" (x)

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    3. So that's why I've been using it? I didn't even pick up on that!

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  16. Are these transitions to different possible trajectories in some nonphysical or pre-physical space?

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  17. Physicsworld: Do solar neutrinos affect nuclear decay on Earth?

    Data accumulated over many years shows that nuclear decay rates correspond to various solar activities. So does neutrino production; so under the logic of many science professionals, it is natural to say that neutrinos cause anomalous nuclear decay.

    Anomalous nuclear decay implies that a fifth force of nature is at play producing weak force anomalies in the Sun.

    But according to the Standard model, neutrinos are not force carriers. Saying that neutrinos generate a fifth force is sticking a pin into the Standard model. Also, the fifth force coming out of the Sun sticks a pin into the posit that many in science express that the fifth force is derived from dark matter.

    How can all this mess be appropriately adjudicated?

    As I see things, a major constituent of the Sun's photosphere is metallic hydrogen. The Sun broadcasts megatons of metallic hydrogen into space every day in the solar wind. Metallic hydrogen is a superconductor that is the primary feedstock for dark matter. When the exotic vacuum object that forms around the metallic hydrogen invariably becomes unstable when its Higgs field energy content becomes large, it explodes in a EVO terminating Bosenova. The Bosenova generates a dark photon that acts as a Leptoquark, the force carrier for the fifth force associated with grand unification of forces carried by the EVO.

    To tie all the various anomaly fifth force threads together, I predict that the The g – 2 experiment and The B meson anomaly data will show variations in their associated data sets that directly correspond to measured anomalous nuclear decay data produced by solar activity.

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    1. Metallic hydrogen is a state where under great pressure H_2 molecules transition into a lattice of monohydrogen. This might be compared to a lithium. The hydrogen in the photosphere is a plasma, mostly protons and electrons at 5400K. While this is conducting, as all plasmas are, this is not metallic hydrogen. Metallic hydrogen occurs at 250K atmospheres and is likely a constituent of gas giant planetary cores.

      The ionized gas of the solar photosphere is 5400K and the average energy of charged species in the plasma in electron volts of energy is on the order of an electron volt. I am doing number in my head, but this sounds about right. The Higgs particle occurs at 125GeV or 1.25x10^{11} electron volts. While the sun is hot, it is nowhere hot energy to generate the Higgs particle. Even the solar center in the 10 million K range is nowhere near enough to generate the Higgs particle.

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    2. The core temperature of the liquid metallic hydrogen interior of Jupiter: a failed star may be about 24,000 degrees Celsius (43,000 degrees Fahrenheit). That's hotter than the surface of the sun. So pressure is a determinant factor in the state that metallic hydrogen will assume.

      Liquid metallic hydrogen provides a compelling material for constructing a condensed matter model of the Sun and the photosphere. Like diamond, metallic hydrogen might have the potential to be a metastable substance requiring high pressures for formation. Once created, it would remain stable even at lower pressures. The metallic form of hydrogen was initially conceived in 1935 by Eugene Wigner and Hillard B. Huntington who indirectly anticipated its elevated critical temperature for liquefaction (Wigner E. and Huntington H. B. On the possibility of a metallic modification of hydrogen. J. Chem. Phys., 1935, v.3, 764–770). At that time, solid metallic hydrogen was hypothesized to exist as a body centered cubic, although a more energetically accessible layered graphite-like lattice was also envisioned. Relative to solar emission, this structural resemblance between graphite and layered metallic hydrogen should not be easily dismissed. In the laboratory, metallic hydrogen remains an elusive material. However, given the extensive observational evidence for a condensed Sun composed primarily of hydrogen, it is appropriate to consider metallic hydrogen as a solar building block. It is anticipated that solar liquid metallic hydrogen should possess at least some layered order. Since layered liquid metallic hydrogen would be essentially incompressible, its invocation as a solar constituent brings into question much of current stellar physics. The central proof of a liquid state remains the thermal spectrum of the Sun itself. Although other indicators exist for a liquid photosphere, our focus remains solidly on the generation of this thermal spectrum.

      Regarding: "While the sun is hot, it is nowhere hot energy to generate the Higgs particle. Even the solar center in the 10 million K range is nowhere near enough to generate the Higgs particle."

      With regards to the formation of a false Higgs field, superconductivity provides a "Higgs mode" now being researched in condensed matter physics whereby a false Higgs field may form using a method of gradual accumulation of energy over time supported by polariton condensation.

      This superconductive seeding nature of metallic hydrogen is the threshold whereby a cosmic false Higgs field can be self assembled. This false Higgs field formation mechanism is a closed system that is independent of the external environment.

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    3. It is better to say that in superconductivity the breaking of the U(1) symmetry is due to a Ginsburg-Landau potential that results in a degenerate vacuum state. This is not really the Higgs field. There are analogous processes with symmetry breaking in laser physics. This is a not the LHC Higgs field.

      My point about metallic hydrogen is that while it exists in the core of Jupiter, which is fairly hot, this thermal energy is far less, in the electron volt range or so, than the 125 billion electron volt range. In the atmosphere of the sun hydrogen is in a plasma state, not a metallic state.

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    4. Provided that the theory of the Higgs particle originates from that of superconductivity and that the Higgs particle has been discovered in LHC experiments in 2012, it would be rather surprising that an experimental observation of the Higgs mode in superconductors, a home ground of Higgs physics, has been elusive for a long time. There are, however, good reasons for that: The Higgs mode does not have any electric charge, electric dipole, magnetic moment, and other quantum numbers. In other words, the Higgs mode is a scalar excitation (which is distinct from, e.g., charge fluctuations). Therefore it does not couple to external probes such as electromagnetic fields in the linear-response regime. Another reason is that the energy scale of the Higgs mode lies in that of the superconducting gap, which is in the order of milli electron volts in typical metallic superconductors. To excite the Higgs mode, one needs an intense terahertz (THz) light source, which has become available only in the last decade.

      Furthermore, the Higgs mode in superconductors (where the Anderson-Higgs mechanism is taking place) are collective amplitude modes that are not limited just to superconductors but are ubiquitous in condensed matter systems that may not be coupled to gauge fields (hence without the Anderson-Higgs mechanism). Those include squashing modes in superfluid 3He , amplitude modes in bosonic and fermionic condensates of ultracold-atom system's amplitude modes in quantum antiferromagnets and so on. A comprehensive review including these topics can be found in Pekker D, Varma CM. 2015. Annu. Rev. Condens. Matter Phys. 6:269.also... Amplitude / Higgs Modes in Condensed Matter Physics - https://arxiv.org/pdf/1406.2968

      Science can look for dark matter particles till the cows come home but none will be found. The key to understanding dark matter is the understanding of the application of the Higgs mode to cosmic micro superconductors and the behavior of the false Higgs vacuum.

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    5. Once formed, metallic hydrogen will remain intact regardless of the temperature and pressure that it is exposed to because metallic hydrogen is degenerate matter.

      In order of increasing density, common forms of degenerate matter include metallic hydrogen, present in large amounts in the core of massive planets such as Jupiter and Saturn; white dwarf matter, found in white dwarfs, which our Sun will one day become.

      But there are other cosmic micro superconductors present in space.

      A recent study sponsored by the US government reports the presence of superconducting material in two meteorites. These are the first superconducting materials found in extraterrestrial samples. These superconductors have been characterized as alloys of lead, tin and indium. These findings could impact our understanding of several astronomical environments. Superconducting particles in cold environments could affect planetary formation, shape and origin of magnetic fields, dynamo effects, motion of charged particles and other processes.

      This suggests the possibility that superconducting material phases could also be found in interstellar grains deep within the coldest regions of space, where these phases would be in a superconducting state. For example, cold, dense molecular clouds have typical temperatures as low as 10 K , but in regions with particularly low ultraviolet stellar radiation, temperatures are estimated to be as low as 5 K or even colder. In unusual parts of space, temperatures can be even lower. The superconducting phases detected in these meteorites would be superconducting in these regions. Furthermore, other metallic alloys have been shown to have critical temperatures above 10 K, which could exist naturally if they could be created in similar conditions.

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    6. Axil wrote: Once formed, metallic hydrogen will remain intact regardless of the temperature and pressure that it is exposed to because metallic hydrogen is degenerate matter.

      Sorry that is false.

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    7. Note how Axii's claim went from 'metallic hydrogen might be metastable' (a better way of phrasing that is 'metallic hydrogen is probably not metastable) to 'metallic hydrogen is definitely stable' in 48 hours.

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    8. @Scott

      The form that hydrogen assumes is based on the context. Hydrogen can be a gas, liquid, or a solid and assume metallic form based on its temperature and pressure. When in space, I believe that metallic hydrogen will become dark matter when exposed to electrons and photons. In that form, that bubble of false vacuum will remain in tact until the false vacuum eventually reaches a point of instability, whereupon it will explode in a Bosenova.

      When this dark matter is dormant, it is not affected by any perturbations in the environment of our de Sutter space time. In terms of string theory, the false vacuum that develops around the metallic hydrogen seed becomes a brane of anti de Sutter space that interacts with our universe via the grand unification of forces that that brane expresses and the associated particles therein until the false vacuum becomes unstable. The false vacuum becomes the prime mover as dark matter that supersedes the nature of the subordinate metallic hydrogen seed.

      In another context, under very high pressure and temperature found in gas giant planets and in the core of the Sun, the metallic hydrogen forms a plasma of degenerate matter that becomes a global collective hole superconductor where the protons form cooper pairs and the electrons form shells that surround the positive core. The protons may form a solid lattice. While in this state of charge separation, metallic hydrogen cannot support the development of a false vacuum. However, the rotating monolithic electron shell(s) that form around the aggregate collective positive core may generate the huge magnetic fields seen in the Sun and the gas planets.

      See the work of J E Hirsch for an explanation of hole superconductivity.

      Because of the huge temperatures and pressures involved, the solid plasma state inside planets and the core of the Sun should not be thought of as the gaseous plasma state that is produced here on earth even if both demonstrate charge separation. Such plasma takes on the nature of a liquid or a solid even when exposed to isolated low intensity fusion reactions.

      Finally, the energy rich environment near and on the surface of the Sun supports an ideal staging area where dark matter can form and be broadcast into space as solar wind.

      Delete
  18. Sometimes it is not a good idea to say gravity is not a force.
    I am a retired physicist who attends courses in philosophy. In a lesson I mentioned that “Schwerkraft” (gravitational force) is an illusion invented by I. Newton. One half of the students laughed, the other one was upset, and the professor said: “Next you will tell us that the earth is flat.”
    I felt a little bit provoked and answered: “In first order, yes.”
    Now, I have the problem not to be taken seriously by some people.

    ReplyDelete
    Replies
    1. Saying that the gravitational force is an illusion is very different from saying that gravity is not a force.

      Delete
    2. I think in the excitement of Einsteins discovery we lose sight of Newtons achievement. I would suggest that gravity is both a force and the curvature of spacetime. The difference lies in the perspective you take. After all, you say that the earth is flat to a first approximation and to a second approximation, it is a sphere.

      Delete
    3. “Saying that the gravitational force is an illusion is very different from saying that gravity is not a force.”
      I thought long about it, but I do not see a big difference. If gravity is not a force, that means for me that I do not deny that there is gravity, but I deny that there is a force caused by gravity which I call gravitational force.
      The idea that something exists, which does not exist, I call an illusion.

      Delete
    4. Understanding that gravity is the effect we attribute to the curvature of space-time doesn't mean the gravitational force is an illusion but it's an approximation (an approximation to a more widely applicable theory). You can deny the validity of that approximation all you wish but that doesn't make it go away.

      Delete
    5. . . . and if Æther makes a comeback, then it’s simply a compression of the medium.

      luminiferous æther = light-bearing (for the propagation of light) killed off by unanimity in 1897
      quantiferous æther = quark-bearing (for the propagation of light and matter) postulated in 2014

      Delete
    6. According to Einstein's general theory of relativity, matter tells space how to curve, and curved space tells matter how to move. It makes for an interesting 'philosophical' debate about whether or not gravity should be considered as a 'true force', but for all practical purposes treating it as one seems to work out just fine.

      Delete
  19. To the guy who is upset that his comments don't appear: I do not approve links other than to published literature or well-known news pages, please read the comment rules.

    ReplyDelete
  20. This comment has been removed by the author.

    ReplyDelete
    Replies
    1. Hi, Jonathan.
      I think: nothing wrong,
      but if I was forced to point out a potential for fallacy I'd say:
      First things first...
      if there is no point in pointing out motion...
      it's of no matter to point it out.

      . ^.^ , °[ Now I need to find out, what I wanted to say. ]

      Delete
  21. Sabine, you say:

    These 25 particles are held together by four forces.
    That’s 1) gravity, …, 2) the electromagnetic force, that’s “a combination of the electric and magnetic force which really belong together, …”

    That is physically not correct. We have an electric force, but the magnetic force is a side effect of it, a relativistic one; in some analogy to the fact that the Coriolis force is as well not an own force but the Newtonian one seen from a certain perspective.

    This explanation can be found in textbooks about special relativity. A detailed deduction is given in: W.G.V. Rosser, “Classical Electromagnetism via Relativity”. Rosser deduces Maxwell’s theory on the basis of 1) the Coulomb law; 2) the Lorentz transformation.

    Einstein has said it in this way: “What led me more or less directly to the special theory of relativity was the conviction that the electromotive force acting on a body in motion in a magnetic field was nothing else but an electric field.”

    ReplyDelete
    Replies
    1. antooneo,

      The electric and magnetic force can't be separated because they mix under Lorentz-transformations. That's why it's called the electromagnetic force. The magnetic force is not a "side-effect" of the electric force, they simply belong together.

      Delete
    2. Sabine,

      You refer to the formalism of the Lorentz-transformation. But look at the physical cause. Magnetism is the consequence of the finiteness of c. This causes that for a moving observer (maybe a moving electron) temporal shifts of the field occur. And these shifts have the effect that such observer will see a resulting electric field, even if it is neutral in a static view. So, if the speed of light would not be finite, there would be no magnetism in the world.

      You refer to the Lorentz-transformation. Also this and so special relativity is the consequence of this finiteness of c. All phenomena of SR can be deduced as consequences of this finiteness.

      This now has the interesting consequence that not only the electric field but any field has its magnetism as relativity applies to any field. So also the strong force, where the magnetism is, however, difficult to observe. But the Pauli Principle is a consequence of just this “strong” magnetism. Which is otherwise not explained.

      And again to Einstein: He also has clearly stated that the magnetic force is in truth the electric force.

      Delete
    3. antooneo: A charge with an electric field E in a stationary frame with that charge, has according to a frame moving at velocity v a transformed field

      E’ = γ(E – v×B)

      where this transformed electric field E’ is a mix of the electric field in the rest frame with a magnetic field B. Here γ = 1/√(1 – (v/c)^2) is the Lorentz gamma factor. The force on a charge in this new frame is F = qE’ = q γ(E - v×B), and for v not relativistic γ ≃ 1 and this is the Lorentz force.

      Every electric motor passes a current through a wire. Since these charges are moving their electric field transforms in our frame into an electric plus magnetic field. We then have these wires wound up and their magnetic field attracts and opposes the magnetic field of a stationary magnet. The inverse happens with a generator. We have built our entire world for over a century on the basis of special relativity.

      Delete
    4. Lawrence Crowell:

      your equations are correct. But they do not show the physical origin of magnetism. Magnetism is a force which acts in specific cases on a charge if the charge is in motion, but not if the charge is at rest. The reason is that for an object (or a system) in motion the view at certain situations changes relativisticly.

      For the case of magnetism there is a very imaginative presentation at Versitasium which makes this situation understandable. You find it at
      https://www.youtube.com/watch?v=1TKSfAkWWN0

      I also refer to again to Albert Einstein, originator of relativity. Also he has stated that the magnetic force is in truth the electric force.

      Delete
  22. Hi Sabine,

    though I like the symmetry of it, I thing you have a typo:
    "it makes frequently makes headlines".

    You name dark matter as a possible fifth force, but why not the cosmological constant? after all that is pressure and pressure is force (and btw could it mean a force carrier ?).

    Best,
    J.

    ReplyDelete
    Replies
    1. Hi akidbelle,

      Yes, generalizations of the cosmological constant are also often referred to as a "fifth force", I mention this when I talk about long distances in cosmology. There is however no reason to think at the moment it's anything but a constant of nature. The case for a fifth force mediated by dark matter is more convincing, I think. All very speculative of course.

      (Thanks for pointing out, I fixed the typo.)

      Delete
  23. As ‘5th forces’ go my own favorite is one that shows up like the Cheshire cat’s smile, only to fade away when looked for by others. I’m referring to the sometimes you see it, and sometimes you don’t, detections of acceleration signals apparently emanating from superconductors under certain conditions. To investigate claims by Eugene Podkletnov, and his physicist colleague Giovanni Modanese, of very brief (~ 100 micro-seconds) gravity-like impulses from their “Gravity Impulse Generator”, Martin Tajmar and Istvan Lorincz at the Technical University of Dresden, in Germany, conducted a series of experiments in 2015 that approximately followed the experimental protocol of Podkletnov. They authored two papers describing their efforts and results. The 2nd paper is titled: “Null-Results of a Superconducting Gravity-Impulse-Generator”, in which they reported no acceleration signal detected by their Colibrys – SF1500SN.A accelerometers above their noise limit of 48 micro-g’s.

    The first of these papers titled: “Design and First Measurements of a Superconducting Gravity-Impulse-Generator” detailed their preliminary work at reproducing the experimental claims of Podkletnov/Modanese. Since very similar, but much simpler, experiments were conducted by Claude Poher in France, and myself in the United States, the Dresden team chose to attempt replication of these experimental procedures rather than the much more elaborate experiments detailed in a number of papers authored by Podkletnov and Modanese. It’s also worth mentioning that George D. Hathaway, of Hathaway Consulting Services, Toronto, Canada, also carried out attempted replications of Podkletnov’s experiments in the early 2000’s. I have his paper: “Force Beam and Gravity Modification Experiments: An Engineer’s Perspective”, but not his group’s later paper describing the results of their attempted replication of Podkletnov’s “force beam” experiments. In this first paper Hathaway Consulting found it very difficult to meet all the requirements of Podkletnov’s device and had to make various compromises. They found no evidence for the weight reduction effect, above the superconductor, reported by Podkletnov.

    In the 2nd paper by Tajmar and Lorincz they concluded that the ‘positive’ detections of acceleration signals by Poher and myself were the result of electromagnetic impulses (EMP’s), which makes eminent sense. I’m now planning to redo my experiments utilizing the strategies that the Dresden group applied to suppress EMP’s. One source of false detections originated from the acoustic ‘pop’ as the cryofluid expanded during a discharge of 1.2 megawatts directly through my YBCO superconductor, or through a heavy gauge coil surrounding it. So I put together a circuit using a 556 dual timer IC which introduces a 350 microsecond delay on the capacitor bank discharge from the moment the RF transmitter button is pressed that triggers a thyristor to dump the accumulated charge through the YBCO superconductor load. This allowed the trace on my Textronix 465B scope (set for single sweep, 100 microsec./div) to reach 3 and ½ graticules on the screen where the anomalous signal should appear (if it really exists), while the acoustic impulse should show up another 3 and ½ graticules further along.

    It’s probably not likely that any anomalous signals will show up in these upcoming experiments. But there’s no harm in trying.

    ReplyDelete
  24. One thing I neglected to mention in a previous comment is that in their 1st paper “Design and First Measurements of a Superconducting Gravity-Impulse-Generator”, Tajmar and Lorincz reported (on page eight) 3 anomalous signals: “During these 14 test discharges we observed three anomalous readings of the accelerometer with the oscilloscope. Since they were not repeatable, e.g. appearing in all the discharges, we can not conclude anything specific from them at this point but for the sake of completeness we show one of the readings in figure 10.” In the next paragraph they state: “A possible explanation for these readings could be that the signature of the EMP changed after each discharge, since the mechanical vibration of the support structure of the disc (deduced from the increased acoustic noise) could have caused the disc in fact to change position between the electrodes”. This I found to be a bit tantalizing, as also in my own experimental runs only a few yielded acceleration signals. My upcoming experiments should clear things up one way or another as I will have EMP suppression techniques in place.

    I also forgot to mention the outstanding work of Frederick N. Rounds dating back to the late 90’s. His paper: “Anomalous Weight Behavior in YBa2Cu3O7 Compounds at Low Temperature” is on the arXiv. He found a sudden weight change in his “target” mass during the transition of his YBCO chip into the non-superconducting state. His experiments are very carefully documented and well worth reading. This is something I would also like to try replicating.

    ReplyDelete
    Replies
    1. @David Schroeder

      Regarding: "He found a sudden weight change in his “target” mass during the transition of his YBCO chip into the non-superconducting state"

      There may be an effect at play here that has confused many experimenters over the years and has produced failure in the experiment.

      Effects will not be detected when the system is in a state of coherence because of quantum superposition that is supported by superconductivity. Only when coherence is terminated does the system produce detectable results. Experiments done under an uninterrupted steady state may not show results.

      As a general experimental method, you might try to execute your experiments in an off/on cycle.

      Also look for Bremsstrahlung as the energy carried by high energy electrons in the system that had been in the state of superposition is released at the termination of the coherent state.

      Delete
    2. Hi David,

      reading Poher in full, it appears that the current density and the discharge slope (dI/dt) must not be too high, otherwise there is no effect at all. So a larger emitter will have less current density - that may explain why Podkletnov emphasises so much on size. Poher also showed (on his website) that thinner larger emitters have larger effect.

      But in my opinion the true difference between the two experiments is that Poher reports a direct push with the same direction as the electrons current (flip the emitter, the push is reversed), with direction opposite to the distant push but on both sides, attractive on one side and repulsive the other side. So I think it looks pretty much like a gravity diode - assuming the effects are not artifacts and gravity, of course.

      I hope you succeed.

      Delete
    3. Thank you, Axil and akidbelle for your very considerable interest.

      Axil, thanks for your very cogent observations. I’ve also long assumed that a system in a steady state will result in no effect being seen. My operational assumption is the effect arises from the acceleration of the condensate, whether by mechanical (Tajmar group), or electromotive (Podkletnov, Poher, and others). I actually mused about the idea of imparting a truly gigantic acceleration to a rod shaped superconductor, properly insulated, by firing it out of a gun barrel. Just looked at a Reddit post where it was calculated that the bullet in a Glock 17 pistol undergoes an acceleration of nearly 63,000 g’s. By comparison the Tajmar group at the Austrian Research Center (ARC) imparted only 7.33 g’s in their spun-up niobium superconductor, for an acceleration signal yield of around 100 micro-g’s. So, if the claimed effect is directly proportional to acceleration, firing a cooled down, insulated niobium rod from a Glock 17 would yield about 0.85 g’s, in principle.

      Akidbelle, I especially thank you for looking at Claude Poher’s website, most of which is in French which I wasn’t able to read. I long ago read the English language portions of his website, but have forgotten my password to enter it. Dr. Poher is a highly accomplished scientist having worked in both the astronomy and aerospace fields. Now, that’s very interesting about the current density as a factor in the reported effect showing up. As you point out that would be the underlying explanation for Podkletnov’s insistence on a certain size emitter. What you said about an attractive force on one side and repulsive on the other is something that I’ve assumed was the case for a very long time. It’s, in fact, integral to a very speculative theory that I conceived back about the time when Podkletnov first came into public prominence.

      I’ve retrieved and dusted off my old equipment from the basement which last saw use about 6 years ago. The main project board is fairly complex with four separate battery power supplies for isolating high and low voltage sections. It took me a long time to work out all the electronic bugs, mainly associated with the huge currents during discharges feeding back through the circuitry and blowing out delicate components. That problem was ultimately fixed with opto-isolaters. Will likely need to order new YBCO superconductors, as moisture has probably chemically altered my old ones. But once everything is up and running its back to searching for this elusive ‘5th force’, with new, innovative approaches.

      Delete
    4. Hi David,

      I think we should try to communicate directly with each other; there are many important details that you seem to ignore; for instance commercial YBCO superconductors wont'work without a bit of work. Also Poher now uses emitters made (mostly) of graphite powder and claims they work better (and certainly cheaper, no need for liquid nitrogen).

      And btw, he removed passwords some time ago (- but still mostly in French).

      Best,
      J.

      Delete
    5. Hi Akidbelle,

      Yes, I agree that it's far better to learn of the findings of Dr. Poher, who has done far more extensive work in this area than I have, so I'll have better experimental guidance. I was very disappointed with the hobbyist grade YBCO discs. They were badly warped making it a challenge to make full body electrical contact across their entire surfaces. Actually the theory I mentioned in the earlier comment also expects non-condensed matter to be a signal source, but lacking coherence it would be much less concentrated. I'm very happy to see that Dr. Poher is continuing his research, and will look at his site again, now that passwords aren't needed anymore. Not sure how to give you my email address without posting it publicly. Perhaps if we both sent our email addresses to Sabine she could forward them to each of us.

      Delete
    6. Hi David,

      I am not sure Sabine wants to be hired as postwoman. I will try anyway..

      J.

      Delete
  25. Hi David,

    I'm probably on the wrong track here and ask that you indulge my question. Reading your first comment, I wondered if it could be that Podkletnov and Modanese made their experiment over-complicated by design or by accident so that some sort of glitchy artefact would be recorded, that they claimed was a result?

    ReplyDelete
    Replies
    1. Maybe in the lab, but they report it 2 Km away... yes 2000 meters, and also photons scattering. I guess they also ran the discharge with a fake emitter to make sure there is no artifact.

      Delete
  26. C.T.,
    I'm not sure there is experimental evidence that the speed of gravity is the same as the speed of light even with the detection of gravity waves. It just seems like it ought to be the same.

    ReplyDelete
    Replies
    1. C. Thompson,

      There are times when I wonder whether Podkletnov actually built the devices that he and Modanese so extensively write about. The reason for this uncertainty is I do not recall any photographs of any of their devices ever presented in any paper, just diagrams. I would have to peruse their papers to double check on that, I could be wrong. Without doubt their claims of gravity-like effects are the most spectacular of any reported. On the other hand if it’s all on the level the parameters of their claimed experiments greatly exceed those of any other group attempting to replicate them, particularly with regard to voltages and power levels. But I do find it hard to rationalize why there’s anything special about the diameter of the emitter, for example, in their Impulse-Gravity-Generator, which Podkletnov emphasizes is very critical for the phenomena to show up.

      As far as the complexity of their setup causing a “glitchy artefact”, I would think that as professionals in their respective fields Podkletnov and Modanese would have a good handle on sources of false positives. In any case their report of a rubber pendulum bob being set into damped, oscillatory motion by a very brief push from their Impulse-Gravity-Generator, hundreds of feet away, would be hard to explain other than by their claim of a collimated, gravity-like “force beam” that persists for some 100 micro-seconds with each discharge. The sci-fi geek within me wants to believe these things, but my degree of conviction would be greatly enhanced if there were, say, Youtube videos of their experiments in progress, or pictures of their apparatus (I will check their papers on the arXiv). So for now my focus is on studying the very professional and more transparent work of the Dresden group, as well as doing experiments of my own.

      Delete
    2. Thanks Dave, that's interesting. I hope you turn up some solid positive results.

      Delete
  27. Thanks Steve & Dr. Hossenfelder.

    I just assumed that gravity waves would move more slowly than light, since gravity makes things weighty, but I've been disabused of that naive assumption. :)

    ReplyDelete
  28. Do all bosons carry forces that have multiple components/sides (in the way a photon has an electric and a magnetic component)?

    ReplyDelete
  29. Everything is in motion. You, like everything else, are falling through space, following the path of least resistance. The only reason that you are standing on the floor is because it is in the way preventing you from falling any further in that direction.
    Is that a fair statement?

    If space, time, and gravity are so intimately connected with each other as to be considered one, shouldn’t we be looking for a spacetime-graviton, or is that implied?

    I think that gravity is an apparent force caused by the curvature of spacetime.

    Sabine said:
    “So, if you read headlines about a fifth force, that just means there’s some anomalous observation which can be explained by a new fundamental interaction, most often a new particle. It’s a catchy phrase, but really quite vague and not very informative.”
    My reply:
    They’re obviously not talking about you.

    ReplyDelete
  30. Sabine,
    Thanks! I remembered the incident but not the details. For those who might be interested, on August 17, 2017 gravitational waves were detected from the merger of two neutron stars. The detection event lasted about 100 seconds and was accompanied by a short gamma ray burst observed 1.7 seconds after the start of the gravitational wave detection. The event happened in NGC 4993, a galaxy about 140 million light years away.

    So, regarding the speed of gravity and the speed of light being the same, as far as I'm concerned, thats good enough.

    ReplyDelete
    Replies
    1. Steve,
      As you indicated the detection of short gamma ray burst observed 1.7 seconds after the start of gravitational wave detection from the merger of two neutron stars in NGC 4993, a galaxy about 140 million light years away is convincing evidence that the speed of gravity is nearly the same, if not the same as, as the speed of light.

      From the very first binary pulsar system discovered in the 1980s, PSR 1913 + 16 (The Hulse-Taylor binary) researchers have confirmed the speed of gravity equal to the speed of light with a measurement error of only 0.2%!

      Delete
  31. Aristotle had a definition of force that I feel is pretty accurate. It is when an agent capable of causing change is in contact with a substance that is capable of changing and actually does change. Notice all the qualifiers which marks him out as a true scientist. This is valid for gravity and electromagnetism. The substance capable of changing in the former being spacetime itself and in the latter, the electromagnetic field. Its only with the advent of quantum theory with its spooky action at a distance that this model breaks down. Thats not bad for a characterisation that was written down 2,500 years ago. Really, physicists should wittering on about all the ways Aristotle got things wrong - all physicists get things wrong as physics is a work in progress - and think about all the ways in which Aristotle was right. Personally, I think he should be inducted into the pantheon of great physicists. There are very good reasons why he was admired for so long.

    ReplyDelete
    Replies
    1. Maybe a reason why the quantum theory is puzzling comes from the fact that its inner logic only concerns and works for events occurring and measured here and now, at the border between the past and the future ; hence in a locally flat world (R = 0)?
      Hence the Heisenberg's uncertainty principle?

      Delete
    2. @Paps57:

      Thats a very interesting point of view and one that I feel the physics community has done little to explore. The question of time, in its many ramifications, is one of the key problems of quantising gravity. Lee Smolin, one of the founders of the modern theory of loop quantum gravity, in his book, Time Reborn, has come round to this view. Before this conversion, he was a supporter of the block theory of time, where time is timeless, in that there is no past, present or future and that the whole of time is to be understood as one block. He supported this view because of how he understood General Relativity. He came round to the view that time was real, and that there was a real present - and so time reborn - because of the questions that Quantum Theory posed.

      I'd like to add that Aristotle noted that there were questions raised in logic because of time. This is important because logic is usually presented as transcending time. I think that this is a clue in thinking about space, time and the quantum which hasn't been explored sufficiently apaet from some radical quantum theorists like the Brazilian school of logicians who have tried to smuggle in the notion of contradiction into quantum theory.

      Delete
  32. Pin em to the wall with your 5th Force, Sabine.
    Looking forward to Saturday.

    ReplyDelete
  33. I'm imagining gravitons as collecting around/within objects according to their mass, and affecting the flow of time around masses as a collection of fields with gradients.
    Is this a workable idea?

    ReplyDelete
  34. Dr. Hossenfelder,
    It seems to me that there are other forces in nature that we have yet to discover and understand. It also seems to me that we do not have a firm grasp on understanding the forces we claim to know about now. Having made this statement please forgive my heresy, but I have to note my disagreements with part of you post. I do not believe that the weak and strong nuclear forces should be considered forces as they are not at all like the E&M or gravity. I have a number of reasons for reaching this conclusion but I will keep this short. Regarding the weak nuclear force, it is not a force it is an interaction (as you stated). The most glaring issue associated with the weak nuclear force/interaction is its right-handed spin asymmetry. What force in nature is able to pick what it interacts with? It seems to me that the wise path would be to identify what acts on right-handed spin particles like the weak nuclear force does with left-handed spin particles. Specifically, particle physics tells us the neutron has about a 10 minute half life so what is acting on right-handed spin neutrons? Additionally, what other force needs the higgs boson to provide it with its necessary mass so that it can interact with particles?
    As for the strong nuclear force, particle physics tells us that quarks are never found singularly in nature. This suggests that they must be created in some form of two or more all at once, which in turn would required the quarks must be created with the necessary gluons already in place. If gluons come with created quarks the inference would be that gluons are not created singularly which could effect the production of neutrons and protons as well as the exotic quark combinations.
    It seems that the W & Z boson interactions are well established and I am not saying that this interaction does not exist. Rather it is my position that the weak force/interaction is not a force. As for the strong nuclear force, rather than being confined to quarks, just the right amount of force travels outside of the proton and neutron quark cluster to bind these particles into atomic nucleus. To me this seems to be a bit more range than simply binding quarks. And, if this attraction is confined to the quark cluster in the proton and neutron, would it not shift the quark cluster mass inside of the proton and neutron? This in turn could set up a situation where the extra gluon force might not be able to interact with the quark cluster in an adjacent proton or neutron creating and instability in the atomic nucleus.
    Thanks for all of your work with your post(s), and for your patience with a retiree who asks to many questions.

    ReplyDelete
  35. If there is a dark matter particle, is it likely it obtains its mass by interacting with the Higgs field, or is it probable there is some other field responsible for at least part of its mass?

    ReplyDelete
  36. Re your excellent article: string theory is apparently helping the field of mathematics. But as a physics idea, it has no experimental support, and no clear way to be tested. So it can’t yet be taken seriously.

    ReplyDelete
  37. Steven Weinberg (1933-2021) passed away today July 25, 2021. He was an American theoretical physicist and Nobel laureate in Physics for his contribution along with Adbus Salam (1926-1996) and Sheldon Glashow (b.1932) to the unification of the weak force and electromagnetic interaction between elementary particles.

    Weinberg helped lay the foundation for the development of the Standard Model, a theory that classifies all known elementary particles in the universe, making it one of the most important breakthroughs in physics in the 20th century.

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    Replies
    1. In particle physics, the electroweak interaction or electroweak force is the unified description of two of the four known fundamental interactions of nature: electromagnetism and the weak interaction. Although these two forces appear very different at everyday low energies, the theory models them as two different aspects of the same force. Above the unification energy, on the order of 2.46 GeV, they would merge into a single force. Thus, if the universe is hot enough (approximately 10^15 K, a temperature not exceeded since shortly after the Big Bang), then the electromagnetic force and the weak force merge into a combined electroweak force. During the quark epoch, the electroweak force splits into the electromagnetic and weak force.
      Ref: Wikipedia 'Electroweak interaction'

      Delete
    2. Grand Unification theory GUT is a model that tries to describe the universe. It says that three forces - electromagnetic, weak and strong forces - were once combined into a single force. These are three of the fundamental four forces of nature, which are responsible for all of the pushes and pulls in the universe. If gravity is also combined with these these forces, then the GUT will become the proposed 'Theory of Everything TOE'.
      Ref: Wikipedia 'Grand unification theory'

      Delete
  38. For some good background information about one of the most important, yet most mysterious entities in the universe I suggest watching the YouTube video "Dark Matter: The Unknown Force", Apr 19, 2019.

    ReplyDelete
  39. Here's to dark matter - "May the force be with you!" Sorry bad joke.

    ReplyDelete
    Replies
    1. Hi Howard,

      I'm here for the bad jokes, the random fanfiction, personal reminiscences and music recommendations, oh, and the science.

      I hope a certain controversial physicist contributes the next major physics breakthrough, and we can then say, 'I know her! (Sort of)'.

      Delete
  40. About these four forces, I have always been surprised by the fact that radioactive decay and electro-magnetism, so the weak nuclear force and the electro magnetic force, were two aspects of a same force, the electro-weak force. My under educated mind always held it more plausible that the radio-active decay of atomic nuclei was more related to the strong nuclear force, and this nuclear decay process was more or less like the decay of gravitaional decay of orbits due to some instability in the gravitational bound system, and so only a residual effect of the force of gravity....

    ReplyDelete

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