12 ms·

is there any reason to believe space is in fact quantized? why should it be? genuine question!

by drsnow 5y ago

Zenst 5y ago
If you look at it with the analogy of vinyl records and digital representations of that music. You can reach a point in which you are quantizing something that equally can represent the original in a way that is not discernable in difference (maybe 192khz 32 bit float for some but still quantized). You equally, hit limits in human perception and technology/physics limitations more so. Maybe the universe is always N+1 with N being the best sampling rate known to man. Sure we can infer, but when you want to know the answer to the exact decimal point, sometimes you have to accept that 1/3 is 1/3 and never exactly 0.333333333333 however much recurring you have.
- ncmncm 5y ago
  Hint: 44100 Hz is plenty to exceed any human's perceptual resolution.
  - Zenst 5y ago
    That was my point, just because you can only perceive at one limit, does not mean there is nothing beyond that like Ultrasound. Anyhow, was analogy about perception and sample rates and what your measuring. Clearly didn't make it that clear and sorry for that.
  - Taniwha 5y ago
    And yet I can flash an LED that fast, then turn my head from side to side and see the modulation ....
    - JohnBooty 5y ago
      >> 44100khz > And yet I can flash an LED that fast You have an LED that flashes 44,100 times per second, and you can perceive this?
      - ncmncm 5y ago
        No.
TheOtherHobbes 5y ago
If spacetime is continuous you effectively get infinite precision -> information density - at every point (of which there are an infinite number). This seems unlikely for a number of reasons. This doesn't mean spacetime is a nice even grid, but it does suggest it comes in discrete lumps of something, even if that something is actually some kind of substrate that holds the information which defines relationships between lumps.
- amelius 5y ago
  > If spacetime is continuous you effectively get infinite precision -> information density - at every point (of which there are an infinite number). Even if space is continuous, that doesn't mean we can get information in and out of it in infinite precision. Look at quantum physics. Maxwell's equations don't suggest existence of photons (quantized information). But atoms being atoms, they can only emit and absorb in quanta.
- scythe 5y ago
  People complain about infinite information, but the theory of real fields is complete and consistent, while arithmetic is not: https://en.wikipedia.org/wiki/Decidability_of_first-order_theories_of_the_real_numbers https://en.wikipedia.org/wiki/Decidability_of_first-order_th...
  - j-pb 5y ago
    I often wonder if we simply constructed math the wrong way around. People tend to mentally construct the natural numbers from set theory, wholes from naturals, rationals from wholes, reals from rationals and so on. But what if there is some universe (in the math sense), which is actually complete and decidable, it's just that the moment you take discrete subsets of it, you also remove the connections that make it consistent or complete. The very act of formalising mathematical concepts into words and paper is a quantisation step after all, because both are symbols. Maybe there are proofs that can be inuitioned about (assuming brains are continuuous in some sense) but neither verbalised nor formalised.
    - 5y ago
greens 5y ago
https://en.wikipedia.org/wiki/Cutoff_(physics) https://en.wikipedia.org/wiki/Cutoff_(physics)
peter303 5y ago
That there is a cosmic speed limit may imply one unit of space per one unit of time. Nothing faster.
- derbOac 5y ago
  Someone else asked about their hand moving in a pixelated versus continuous way in reality, and it occurred to me that if spacetime were discrete that would be a good reason for entanglement, intuitively speaking. Otherwise there wouldn't be an obvious way for information to be transferred across the discrete points? Maybe I'm wrong about this but it seems that way on first thought. That doesn't mean anything has to be a particular way, but it at least would be intuitively consistent to me.
  - BoiledCabbage 5y ago
    If it were discreet, why would that be a good reason for entanglement? Could you explain your idea more?
8bitsrule 5y ago
If it's true that the Planck length (1.616e-35 meters) is the smallest possible Length, [https://futurism.com/the-smallest-possible-length https://futurism.com/the-smallest-possible-length] then so far as we'll ever know, space is quantized. When I think about that, I wonder if that 'quantization of space' is what determines the speed of light. And perhaps explains why inertial and gravitational mass are identical.
physicsyogi 5y ago
Since gravity is the curvature of spacetime, quantizing gravity would mean quantizing spacetime (or quantizing geometry) also, which would lead to their being smallest units of space and time, perhaps somewhere around the Planck length and Planck time.

is there any reason to believe space is in fact quantized? why should it be? genuine question!

by drsnow 5y ago

is there any reason to believe space is in fact quantized? why should it be? genuine question!

If you look at it with the analogy of vinyl records and digital representations of that music. You can reach a point in which you are quantizing something that equally can represent the original in a way that is not discernable in difference (maybe 192khz 32 bit float for some but still quantized). You equally, hit limits in human perception and technology/physics limitations more so. Maybe the universe is always N+1 with N being the best sampling rate known to man. Sure we can infer, but when you want to know the answer to the exact decimal point, sometimes you have to accept that 1/3 is 1/3 and never exactly 0.333333333333 however much recurring you have.

ncmncm 5y ago
Hint: 44100 Hz is plenty to exceed any human's perceptual resolution.
- Zenst 5y ago
  That was my point, just because you can only perceive at one limit, does not mean there is nothing beyond that like Ultrasound. Anyhow, was analogy about perception and sample rates and what your measuring. Clearly didn't make it that clear and sorry for that.
- Taniwha 5y ago
  And yet I can flash an LED that fast, then turn my head from side to side and see the modulation ....
  - JohnBooty 5y ago
    >> 44100khz > And yet I can flash an LED that fast You have an LED that flashes 44,100 times per second, and you can perceive this?
    - ncmncm 5y ago
      No.

TheOtherHobbes 5y ago

If spacetime is continuous you effectively get infinite precision -> information density - at every point (of which there are an infinite number). This seems unlikely for a number of reasons. This doesn't mean spacetime is a nice even grid, but it does suggest it comes in discrete lumps of something, even if that something is actually some kind of substrate that holds the information which defines relationships between lumps.

amelius 5y ago
> If spacetime is continuous you effectively get infinite precision -> information density - at every point (of which there are an infinite number). Even if space is continuous, that doesn't mean we can get information in and out of it in infinite precision. Look at quantum physics. Maxwell's equations don't suggest existence of photons (quantized information). But atoms being atoms, they can only emit and absorb in quanta.
scythe 5y ago
People complain about infinite information, but the theory of real fields is complete and consistent, while arithmetic is not: https://en.wikipedia.org/wiki/Decidability_of_first-order_theories_of_the_real_numbers https://en.wikipedia.org/wiki/Decidability_of_first-order_th...
- j-pb 5y ago
  I often wonder if we simply constructed math the wrong way around. People tend to mentally construct the natural numbers from set theory, wholes from naturals, rationals from wholes, reals from rationals and so on. But what if there is some universe (in the math sense), which is actually complete and decidable, it's just that the moment you take discrete subsets of it, you also remove the connections that make it consistent or complete. The very act of formalising mathematical concepts into words and paper is a quantisation step after all, because both are symbols. Maybe there are proofs that can be inuitioned about (assuming brains are continuuous in some sense) but neither verbalised nor formalised.
  - 5y ago

greens 5y ago

https://en.wikipedia.org/wiki/Cutoff_(physics) https://en.wikipedia.org/wiki/Cutoff_(physics)

peter303 5y ago

That there is a cosmic speed limit may imply one unit of space per one unit of time. Nothing faster.

derbOac 5y ago
Someone else asked about their hand moving in a pixelated versus continuous way in reality, and it occurred to me that if spacetime were discrete that would be a good reason for entanglement, intuitively speaking. Otherwise there wouldn't be an obvious way for information to be transferred across the discrete points? Maybe I'm wrong about this but it seems that way on first thought. That doesn't mean anything has to be a particular way, but it at least would be intuitively consistent to me.
- BoiledCabbage 5y ago
  If it were discreet, why would that be a good reason for entanglement? Could you explain your idea more?

8bitsrule 5y ago

If it's true that the Planck length (1.616e-35 meters) is the smallest possible Length, [https://futurism.com/the-smallest-possible-length https://futurism.com/the-smallest-possible-length] then so far as we'll ever know, space is quantized. When I think about that, I wonder if that 'quantization of space' is what determines the speed of light. And perhaps explains why inertial and gravitational mass are identical.

physicsyogi 5y ago

Since gravity is the curvature of spacetime, quantizing gravity would mean quantizing spacetime (or quantizing geometry) also, which would lead to their being smallest units of space and time, perhaps somewhere around the Planck length and Planck time.