Speed Quanta: Is There a Lower Limit?

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we all know that there is upper limit for speed that is speed of light, but is there a lower limit, I mean is there quanta for speed.
 
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There is no quanta for speed.
The effective "lower limit" for speed will be the uncertainty principle, because of the wave-particle duality. The speed of a particle can be arbitrarily close to zero as long as the uncertainty in the position is sufficiently large (i.e. the particle is delocalized).

If a particle is confined to any discrete region of space, there will be a lower limit on its velocity. Hope this helps.
 
lzkelley said:
There is no quanta for speed.
The effective "lower limit" for speed will be the uncertainty principle, because of the wave-particle duality. The speed of a particle can be arbitrarily close to zero as long as the uncertainty in the position is sufficiently large (i.e. the particle is delocalized).

If a particle is confined to any discrete region of space, there will be a lower limit on its velocity. Hope this helps.

Thank you that helped.
 
No, not at all.

The uncertainty principle applies for dXdP, not dXd(mv) which is a slight difference; in the case of light the uncertainty applies to its wavelength, frequency and energy via the relation P = hf/c where f is the frequency or alternatively, P = h/w where w is the wavelength.

Correct me if I'm wrong but that's how it seems.
 
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In the case of light, the lower limit is quite well defined... its still just c. but even in the not photon case, by the deBroglie equation the same relation applies (p=h/L).
dst : your point, thought true, is trivial and semantical. In quantum mechanics there is no way to define an instantaneous (accurate) velocity; however, the concept of spatial motion does apply very closely to momentum --> hence it is the term that we should be looking at, in the "lower limit of velocity."
 
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Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
Is it possible, and fruitful, to use certain conceptual and technical tools from effective field theory (coarse-graining/integrating-out, power-counting, matching, RG) to think about the relationship between the fundamental (quantum) and the emergent (classical), both to account for the quasi-autonomy of the classical level and to quantify residual quantum corrections? By “emergent,” I mean the following: after integrating out fast/irrelevant quantum degrees of freedom (high-energy modes...

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