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Anyone ever wondered is there a least Velocity, acceration?

  1. Dec 30, 2014 #1
    Hello,
    There is a upper limit to velocity of normal material which is the speed of light C,, So I would think there is a lower continuous velocity as well. In other words discarding starts and stops there should be a lower limit to velocity then a jump to zero relative speed in regards to a reference object.

    [Mentors' note: edited to remove some personal theorizing]
     
    Last edited by a moderator: Dec 31, 2014
  2. jcsd
  3. Dec 31, 2014 #2
    Yeah i think this is the reason for zero-point energy. Each particle will have that minimum energy, and hence, a minimum velocity.
     
  4. Dec 31, 2014 #3

    Nugatory

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    It is possible that speeds are quantized in that way, but there is neither any experimental data hinting that they are, nor does any currently known science (the only kind we discuss here) predict that they would be. In other words, as far as we know so far, there is no reason to think that the lower speed limit is anything but zero.

    The analogy with the speed of light as an upper limit is superficially tempting but doesn't really apply if you consider where the lightspeed limit comes from. It's derived from the laws of electricity and magnetism (from which the speed of light is derived) plus some reasonable assumptions about how any physical law should be affected by motion (the details are too long to go into here, but you'll find them in any decent introduction to the theory of special relativity). There's no analogous argument for a non-zero minimum speed.
     
  5. Dec 31, 2014 #4
    If we approach this problem based on classical physics viewpoints, a body can be at rest v = 0 .that is the minimum velocity possible w.r.t any reference frame whatsoever, assuming of course that by 'minimum velocity' you're referring to the magnitude. otherwise , the -ve sign dosen't create a new minimum as they are just a convention to indicate direction and have nothing to do with the minimal velocity attainable. However, if we see this from a quantum standpoint, we can never reach absolute zero K, no matter how much close we get to that magical limiting temperature. and unless we reach that temperature, atoms will have energy, which TENDS to be zero, but never is zero, and hence they oscillate with certain velocities with respect to suitable reference frames which are non zero in magnitude. you may imagine the temperature(x) - velocity(y) graph to be a asymptote where the graph never touches the X axis in reality, though mathematically , it touches the X axis at 0 deg kelvin.
     
  6. Dec 31, 2014 #5
    It can be shown with the Mean Value Theorem at least for classical physics.
     
  7. Dec 31, 2014 #6

    Nugatory

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    You don't need QM for that - classical thermodynamics says the same thing.

    Quantum mechanics is irrelevant here, as at the quantum level the relationship between energy and speed that you're imagining doesn't exist. Even if we apply classical thermodynamics in which the atoms making up an object of non-zero temperature have non-zero average speed, nothing stops any individual atom or the object as a whole from having zero speed.
     
  8. Dec 31, 2014 #7
    Hello,
    I guess I need to move to another forum, any suggestions?

    Thanks

    Dan
     
  9. Dec 31, 2014 #8
    I think this is the best one, physicshelpforum and thephysicsforum are decent for help without condemning deviation from mainstream... but that's what make this one the best because they only tolerate supported and frequently used theories.
     
  10. Dec 31, 2014 #9
    Well I am sort of dead here for my question and discussion. Current theory does not rule out concretely (that I know of) that a min velocity for material objects is reality. However it is vaguely assumed that objects can go forever slower----toward infinity slow. I personally can't discuss this with any current theory that I know about.

    Thanks all, I found another forum that has a open area, hopefully it will be a productive discussion at some level.

    Dan
     
  11. Dec 31, 2014 #10

    Wes Tausend

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    The problem with moving to a different, more open forum, is that one runs into copius uncontrolled (read irrational) philosophy. On the plus side, questions here often get a rational critique that is more personal and direct than a generic Wikipedia explanation. This forum is ideal for a student to learn what we now know... which is it's intent.

    On the downside, very few truly new insights show up here. Sometimes I think it is too bad rational philosophy, other than math, can not be encouraged here without creating a moderator quagmire. Pure math, though valuable, certainly doesn't tell us everything. You might also be able to reword your inquiry so as to not violate rules here. It's worth a shot. The best, most rational minds are found here.

    I might add that the search for thee lower limit of velocity was the reason Michelson–Morley performed their experiment. They basically searched for Absolute Rest to see which way earth might drift in the vast universe "aquarium". The experiment at first seemed a total failure. What they measured was an apparent semblance of "absolute velocity" (light) that Einstein demonstated was just as valuable a tool to discern the "relativity of drift". Absolute Rest isn't needed and has been therefore laid to the side unless somebody comes up with a good reason to resurrect it. The constant speed of light can be determined from Maxwell's equations, but I don't think Einstein, Lorentz and/or Poincaré would have solved Special Relativity so soon without the Michelson–Morley nudge.

    If you find a more liberal forum that isn't also too loose for a straight answer, let me know. I have a least one, somewhat related, unusual question of my own. Good luck.

    Wes
    ...
     
  12. Dec 31, 2014 #11
    Maybe this forum can consider putting up a section for crackpot theories and hypothesis? It seems that the crank posts can be ignored by members and those posts more "worthy" can be discussed?

    Dan
     
  13. Dec 31, 2014 #12

    jtbell

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  14. Dec 31, 2014 #13

    phinds

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    Utter waste of time. ALWAYS devolves into crackpottery and attracts crackpots to the forum. Been there, done that, BURNED the damned T-shirt.
     
  15. Jan 3, 2015 #14

    Wes Tausend

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    Dan,

    Since I have had some "least velocity" questions possibly along similar lines, I am curious what you may have explored in other forums.

    I'm not sure I can message you, but if you would rather reply in private, you are certainly welcome to message, or email me if you can find the needed info in this new forum software. I think you can message me by mousing over the INBOX tab above and choosing "Start a New Conversation". Thanks for your consideration.

    Wes
    ...
     
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