Charge carriers, forces

Discussion in 'Physics & Math' started by Edont Knoff, Mar 26, 2018.

  1. Edont Knoff Registered Senior Member

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    I've been wondering why electromagnetism is the only force that we really can use in a larger scale. Eventually it came to my mind that with the electron we have an easy to access carrier of charge, and a moving charge creates a magnetic field. So with moving electrons we are pretty well set for electromagnetism. And because electrons are part of atoms, and not too hard to split off them, they are available in large numbers and somewhat easy to access for us.

    For gravity, I don't even know if there is a charge particle?

    The strong and the weak force?

    What do you think? Is the lack of accessible charge carriers the reason why we cannot use these forces well?

    Furthermore, fi there is no charge particle for gravity, all the sci-fi gravity control technology will stay fiction, because we lack such a particle?
     
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  3. NotEinstein Valued Senior Member

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    I think this is one of the (if not the) main reasons, yes.

    Hypothetically, the graviton, but it hasn't been demonstrated to exist.

    W-bosons and Z-bosons for the weak force, and gluons for the strong force.

    The main "problem" with the W- and Z-bosons is that they are unstable; they decay pretty quickly, thus rendering the range of the weak force very small. There are no daily applications (that I know of) for such a short-ranged force.
    The main "problem" with the gluons is that they cannot be isolated at the energy levels of daily life; so it's not possible to "use" them without also takin a lot of other particles along for the ride.

    Well, we do have access to gravity, even if we don't have direct access to its force carrier. But it's quite impractical, since you'd need to manipulate a lot of mass to do anything with it.

    Not necessarily; it really depends on what the alternative turns out to be.
     
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  5. origin Trump is the best argument against a democracy. Valued Senior Member

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    I suppose you could say that we 'use gravity for propulsion' when we do a sling shot maneuver with space craft.
     
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  7. NotEinstein Valued Senior Member

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    Good point; many of our contraptions using electromagnetism use it indirectly in exactly the same way. What counts as "using the force"?

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  8. exchemist Valued Senior Member

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    I was going to make a similar point. Using gravity, via the falling of objects or substances (such as water), is one of the most ancient energy sources of mankind.
     
  9. Q-reeus Valued Senior Member

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    We also use the nuclear strong force (in combination with EM) in - you guessed it - nuclear fission (and forever hopeful fusion ) energy plants, nukes, and directly or indirectly in e.g. nuclear medicine:
    https://en.wikipedia.org/wiki/Nucle...des,_with_notes_on_a_few_radiopharmaceuticals
    The latter, and in non-medical radiology, also harnesses the weak force as in certain nuclear decay processes. Bet I've missed something.
     
  10. Edont Knoff Registered Senior Member

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    Sorry for the late reply. I'm still struggling with some health related issues.

    A pity. That would be quite handy to have. I assume that means it's one of the super-heavy particles if it's not been found yet?

    I had been reading about the W- and Z-bosons, but couldn't really make my mind up. Electrons can be collected, e.g. in a capacitor. If the charge bsosons are short-lived, that will make using them really hard. Not onyl they don't reach far, buit also, they cant be stored.

    So far, the beta decay was the only process known to me that included the weak force. Didn't look terribly useful for technical applications, there are better sources of beta rays these days, I guess.

    If we could control gluons better, would that mean we can lower the pressure and temperature needed for fusion? Like, we could raise the attraction of the cores to a similar range than the repulsion by the electric charge? Is this something with a chance of realization, or, due to the effects that you mentions, practically impossible?

    Yes, hard to lug planet sized weights around to counter the gravity of another planet. E.g. to make a space ship lift of smoothly with weak propulsiuon by trying to nullify the gravity of the planet. Also, how to work against the acceleration of these huge masses towards each other? I put more hope into the graviton, if it exist and turns out to be controllable.

    Thanks for all the answers. Seems I had the right idea, but knew too little about all the details.
     
  11. NotEinstein Valued Senior Member

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    Get well soon!

    Not only that, it's not clear that is makes sense for it to exist. It's quite possible it can't: https://en.wikipedia.org/wiki/Graviton#Difficulties_and_outstanding_issues

    Exactly.

    There are even scientists speculating that it would be possible for a universe like ours to exist without the weak force.

    Perhaps, but I wouldn't be surprised if an even better control over electromagnetism would be more useful for fusion.

    I guess, but I don't see how one would be able to do this in practice.

    As long as the issue I described cannot be worked around, I'd say it's the latter.

    That would most likely also cause the disintegration of the planet (due to its surface being no longer bound to the core by gravity). And I suspect the tidal forces would be enough to rip the planet apart.

    I don't know of any solutions given the scenario.

    Yep, anti-gravity would be cool and probably very useful to have.

    No problem! Feel free to ask follow-up questions. Speculating about these things can be very enlightening.
     
  12. sweetpea Registered Senior Member

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    And, for countering the lift of an aircraft wing.

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  13. Edont Knoff Registered Senior Member

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    Just spinning the train of thoughts a bit further.

    Given that the graviton was not discovered at LHC yet, chances seem to be slim that a small and handy machine can produce and control them anytime soon. And we already concluded that the weak and the strong force are fairly out of reach for us, at least if try to use them the same way we use electromagnetism.

    Funnily, the ideas of unified froces say that weak and electromagnetic forces will merge first, then electro-weak force will merge with the strong force and gravity will be the last to merge, if at all.

    To me gravity seems to be fundamentally different because it is linked to the geometry of space, actually (if I have that right) gravity is equvilant to bent space and gravity effects can alternative explained by calculations in bent space, gravity only being the "reason" for the space beign deformed.

    This also gives me little hope for antigravity, because would need to undo the curvature of space ina given region, to counter the effect of a planet. As you pointed out, this presumably is a very destructive operation, unless the the effect can be conatiend to a small volume of space.

    I'm also thinking abotu the one point that you brought up, instead of trying to "improve" the strong force to make fusiuon easier, try to lower the electric rejection of the protons. gave me soem weird ideas of tryxing to fuse neutrons and use beta decay to form a helium nucleus from such a compound. If that would result in a similar amount of energy like fusing protons? Maybe it would be useful to control the weak force and turn neutrons into protons at certain moments. E.g. if a neutron-neutron fusion (probaly instable pair) or neutron-protoc fusion (deuterium, no nergy gain) doesn't work, imagien we could trigger the neutron decay just before the neutrons hit, and the resulting protons are too close to each other alreadys and fused by their inertia.

    Tricky that. And, very speculative, because my knowledge of physics on these scales is not very good.
     
  14. NotEinstein Valued Senior Member

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    I'm not sure if the LHC was ever expected to discover them in the first place. I wouldn't be surprised if there are other experiments being run right now that have a much better chance at it.

    That is most likely true.

    I think this is merely coincidence?

    Pretty accurate, and this thus is also one of the big reasons why GR and quantum theories are so difficult to merge.

    There are some cases where "negative energy" comes in, but I'm not well enough versed to make any definitive statements on that. But these negative energy situations are rare, pretty much edge cases, and of little practical use, as far as I know.

    Right, it needs to be very controlled and directed before we can use it in any practical application.

    Probably very similar, yes, but the question is whether we can do that efficiently.

    Very speculative indeed, but it is certainly interesting to see whether this idea could in principle work.

    Just keep on reading and learning; knowledge is easy to grow!
     
  15. Q-reeus Valued Senior Member

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    A much better chance of zero chance? https://arxiv.org/abs/gr-qc/0601043v3
    He is probably vaguely referring the BB energy hierarchy situation, but in reverse. Spontaneous symmetry breaking leading to de-merging of fundamental forces as universe cooled, would do the opposite in reverse. Energy densities required for currently just speculative merger of gravity with EM, weak, and strong force(s) will always be far beyond human capabilities.
    Not pretty accurate. Gravity as we feel it is essentially all due to the time curvature component of gravity - not spatial curvature.
    There is no known case of overall 'negative energy' anywhere. Folks get variously confused and excited by talk of 'negative energy' but when it's all stripped down, always the net energy content is positive. For instance, gravitational potential energy is negative by definition, but it's always part and parcel of a larger positive energy-stress-momentum source. Similarly for misplaced talk of 'negative Casimir energy' etc.
    Anyone remember a thing called conservation of charge? Something out the window if one could magically turn a neutron into a proton at whim. In isolation a neutron randomly decays into usually a proton + electron + neutrino. And occasionally also a gamma ray: https://en.wikipedia.org/wiki/Free_neutron_decay
    Inside some nuclei, random beta decay can be the generally much less frequent result of above random free neutron process: https://en.wikipedia.org/wiki/Beta_decay
     
  16. NotEinstein Valued Senior Member

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    Erm... from the abstract: "however, when anything remotely resembling realistic physics is taken into account, detection becomes impossible," How is that different from zero chance?

    Yes, I understood that, but why would the force that separates last be the easiest to control by human technology? That was what I called a coincidence.

    Sorry, I read "spacetime" instead of "space". Yes, the curvature of the time-component is also very important.

    I do remember the evaporation of black holes through Hawking radiation sometimes being explained as the infalling particle having negative energy, but as I said, I'm not well enough versed in it.

    I'm leaning towards the same explanation of negative energy.

    I don't think that's being suggested here. To "control the weak force" would probably include the ability of directing W-bosons.

    Sure, and that's one of the reasons why the speculative idea of controlling the weak force is interesting in a practical way: perhaps it could one day be used to help process nuclear waste?
     
  17. Q-reeus Valued Senior Member

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    It's not. Quite my point and why I quoted your relevant reply to Edont Knoff:
    "I'm not sure if the LHC was ever expected to discover them in the first place. I wouldn't be surprised if there are other experiments being run right now that have a much better chance at it."
    Maybe there was a suggestion of 'large extra dimensions' showing up at LHC via decays suggesting 'micro BH formation then decay'. The notion being 'large extra dimensions' might allow gravity to become relatively strong at energies many orders of magnitude below Planck scale. Presumably that in turn would be compatible with non-standard gravitons coming into play. If so, alas there is zilch evidence for such 'large extra dimensions'. And moreover, in those inherently messy collisions, involvement of any putative 'large dimensions gravity' 'gravitons' would at best be inferred never directly detected.
    According to knowledgeable advocates, the means to achieve that has been there for quite some time:
    http://www.transatomicpower.com/
    http://gehitachiprism.com/what-is-prism/how-prism-works/
     
  18. NotEinstein Valued Senior Member

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    Ah, I see. I didn't understand what you meant due to the broken sentence: "A much better chance of zero chance?"
    Also, can I point out to the "I wouldn't be surprised"-part of the sentence you quoted?
    The paper you linked is from 2006, but in 2014 Lawrence Krauss and Frank Wilczek apparently argued it is possible, though indirectly:
    https://phys.org/news/2014-03-elusive-graviton.html

    (No comment.)

    Are you claiming these devices control and direct the weak force?
     
  19. RainbowSingularity Registered Senior Member

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    thats the money question.

    does inertia exist without movement in the vacuum of space ?
     
  20. Q-reeus Valued Senior Member

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    It was duly noted. As was the remainder of that sentence....
    Good luck to them - although Krauss needs luck in a different context of late. The problem with such novel proposals is they are typically plagued with there being a plethora of competing models. Even before the 'B-mode polarizations' debacle had played out, papers came out challenging the primordial GW's interpretation. Pointing out primordial magnetic fields for instance could also create such 'B-mode polarizations' in CMBR. Maybe the Krauss-Wilczek proposal is free from such ambiguities, but I doubt it.
    One thing is for sure - generating such new proposals, just beyond testing with current tech, keeps the funding momentum going for ever more sensitive thus expensive instrumentation and allied. So reminiscent of decades long WinTel combine.
    No. I was referring to the last part of your comment: "...perhaps it could one day be used to help process nuclear waste?"

    Burning up what is for current fission reactors 'nuclear waste' is the perfectly sensible claim made for in particular the PRISM scheme in the 2nd relevant link I gave.
    Transatomic iirc had made much more spectacular claims earlier on re burning low-grade nuclear fuel, but seem to have pulled back recently. An earlier piece on them:
    https://www.extremetech.com/extreme...t-nuclear-reactor-that-eats-radioactive-waste

    Of course as fission processes it involves the weak force, but not in the sense of a fanciful directing of individual decay processes. There are various schemes under the banner of 'direct energy conversion' that use electric fields to channel decay products; e.g. https://forum.nasaspaceflight.com/index.php?topic=18598.0
    None of those afaik claim to manipulate the original decay process - rather take advantage of it after the fact, in a novel way going beyond traditional heat -> steam -> turbine -> alternator.
     
  21. NotEinstein Valued Senior Member

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    I'm not sure what your point is here?

    So there's a non-zero chance, now or "just beyond testing with current tech". Got it.

    Ah, you were going slightly off-topic. OK.

    (No comment.)
     
  22. Q-reeus Valued Senior Member

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    My point was even if the ultra subtle signature is actually detectable and claimed to have been detected in fact, for sure it will be contested. Owing to the zoo of competing inflationary models still considered viable. Planck data has knocked many models out of contention, but still leaves many in the game. And each model will have differing predictions about size or even presence of possibly surviving primordial graviton signature on CMBR. And perhaps other contributors mimicking graviton signature.
    This situation would in turn prompt calls for ever more expensive and sensitive equipment and missions. To settle the matter beyond reasonable doubt. Which is at least a better use of taxpayer funds than e.g. destructive 'regime change' military ventures.
     
    Last edited: Apr 6, 2018
  23. NotEinstein Valued Senior Member

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    Oh, I don't doubt that, certainly considering the shaky ground on which the graviton-concept is built.

    As I said, a non-zero chance, now or "just beyond testing with current tech".
     

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