How is the unit of quantum space time (given) a value

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Discussion Overview

The discussion revolves around the nature of quantum spacetime and the potential limits of energy associated with it. Participants explore concepts related to the unit of quantum spacetime, its value, and implications for energy and particle behavior. The scope includes theoretical considerations and conceptual clarifications regarding quantum mechanics and spacetime.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants question whether the unit of quantum spacetime can be equated with energy and discuss the implications of this relationship.
  • One participant suggests that a complete theory of quantum spacetime may eventually establish an upper limit on the energy a single particle can possess, estimating this limit to be around 2 billion joules.
  • There is a discussion about the relationship between particle energy and wavelength, with references to the Planck length and the challenges of localizing particles at high energies.
  • Some participants express uncertainty about the oscillations in spacetime, suggesting they must be constrained between the speed of light and the Hubble constant.
  • Questions arise regarding the concept of traversing a Planck length in a given time, with some participants debating the implications of time in the context of spacetime theory.
  • One participant acknowledges confusion regarding the nature of Planck length and its relation to quantized space.

Areas of Agreement / Disagreement

Participants express various viewpoints and uncertainties, indicating that multiple competing views remain on the nature of quantum spacetime and energy limits. The discussion does not reach a consensus.

Contextual Notes

Participants highlight the limitations of current understanding in quantum spacetime, noting that fundamental questions remain unanswered due to the lack of a complete theory. There are also unresolved assumptions regarding the definitions of energy and spacetime in this context.

wolram
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Is it energy? how is the unit of quantum space time (given) a value, so it can multiply several times over, is there a limit when the (energy) will be exhausted ?
 
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wolram said:
Is it energy? how is the unit of quantum space time (given) a value, so it can multiply several times over, is there a limit when the (energy) will be exhausted ?

one always needs to point out (even though you and I know this well) that these very fundamental questions are not yet answerable because there is not yet a complete theory of quantum spacetime and matter

but my feeling is that there will be a theory that will be properly completed and checked out so that one can accord it some credibility

and it will probably have a built in UPPER LIMIT on the amount of energy which a single particle can have

and this limit will be roughly on the order of 2 billion joules WHICH IS ENOUGH TO FILL THE PETROL TANK OF YOUR CAR and drive 100 miles or so with. actual mileage may vary, since this is just an order of magnitude estimate------our gracious dame Nereid calls it an OOM estimate.

a single particle carrying that much whallop is quite inconceivable to me, but if there were one then it would have a quantum WAVELENGTH (giving a fuzzy idea of localizing it in space) equal to the PLANCK LENGTH

this is the fractious recalcitrance of nature which fiercely resists being pinned down----you only can clamp a particle wavelength down by increasing its energy-----or else give up and change to a different particle with higher energy and shorter wavelength.

Maybe this upper limit on the energy of particles is not what you asked.

Maybe you are thinking of some upper limit on the combined energy of BUNCHES of particles. Except for accidentally getting so much together in a small space that they collapse to make a hole, I don't know of any upper limit.

=========
always fun thinking about questions you ask wolram, even if often can't give a satisfactory answer
 
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But Marcus ,these oscilations can not excede c and can not be less than
the hubble, so they (must ) be betwicx these two values ?
 
wolram said:
But Marcus ,these oscilations can not excede c and can not be less than
the hubble, so they (must ) be betwicx these two values ?
Can you talk about transversing a Planck length in a giving time? How can you transverse a quantum of something, either it is one or the other, one side or the other side of the Planck length in no time at all, right?
 
wolram said:
But Marcus ,these oscilations can not excede c and can not be less than
the hubble, so they (must ) be betwicx these two values ?

wolram if you completely stump me then I will just have to be quiet and wait for some passerby to tell us the answer

[edit] Ah, Mike2 appeared I see.
 
Mike2 said:
Can you talk about transversing a Planck length in a giving time? How can you transverse a quantum of something, either it is one or the other, one side or the other side of the Planck length in no time at all, right?
sorry Mike but no time at all makes no sense. Spacetime inferses time, as a part of the theory so how can you negate one part of it
 
wolram said:
sorry Mike but no time at all makes no sense. Spacetime inferses time, as a part of the theory so how can you negate one part of it
Sorry, I was thinking of space only. Maybe you're right, chunks of spacetime would include a chunck of time.

But now I'm not sure, ... the Planck length ... that's not the measure of quantized space (only)?
 

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