Is anything in the physical world infinite?

In summary: Are you saying that if the universe is infinite in size, the number of particles in it must be infinite as well?
  • #71
PeroK said:
Within the classical theory of EM there is no such thing as the shortest possible wavelength. Or the longest.
True about the theory, but still a red herring when it comes to physicality.

I have already pointed out practical limits on upper and lower bounds.
 
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  • #72
DaveC426913 said:
True about the theory, but still a red herring when it comes to physicality.

I have already pointed out practical limits on upper and lower bounds.
There's a difference between

A) An EM wave theoretically having any non-zero finite wavelength.

B) an EM wave having a wavelength of zero or "infinity".

The first is what the classical theory says.
 
  • #73
PeroK said:
There's a difference between

A) An EM wave theoretically having any non-zero finite wavelength.

B) an EM wave having a wavelength of zero or "infinity".

The first is what the classical theory says.
I know, and I'm not disagreeing that it's valid; I'm simply pointing out it's a red herring in a discussion about physical phenomena.

IOW, yes the theory of EMR says there's is no upper or lower limit - but the physical limits of universe supercede that, and put a real constraint on what can, and therefore does, exist.
 
  • #74
Melbourne Guy said:
Perhaps I'm misunderstanding the concept, but with the electromagnetic spectrum, can it really be partitioned into an infinite number? Is it not constrained by the shortest wavelength?
The number of different frequencies between 100 MHz and 101 MHz is infinite for example. The shortest or longest possible wavelength is different and not what I was referring to.
 
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  • #75
I assume we are not speaking of infinitely large things or infinity small things. Both are shorthand for limits to what our human mind can comprehend & actually does not relate to a true mathematical infinity. We need to understand that math is all about modeling & math also introduces infinities, it is only a first approximation to the way the world actually works. A match between our experiments & our theories is necessary. Humans have adopted a deconstructionist POV which is very unacceptable at the extremes. Quantum Theory instructs us quantum entanglement has no spatial/temporal limits. Many individuals cannot accept this experimentally provable aspect of our existence. The human mind is not prepared by evolution to grasp the scale of everything all at once, it's instantaneous reality & of our connection to the entire Universe instantly.

As we discover new aspects of the world we add to our long list of models. This is because we have evolved to thrive at certain scale. Our interaction with the world would be quite different if we were the size of a flea, bacteria or the size of a land locked Blue Whale for example. That is all about evolution & fitness for purpose. But actually these models are only (of themselves) purely intuitive & conceptual & do not specifically relate to the physical world on/at all scales. Scale is of utmost importance & it is why we find it difficult to understand our place in our world but I respectfully remind everyone there are no models that have stood forever. The price of Truth is always the properly constructed observation/experiment not our wishing to be something we are not.
 
  • #76
LightningInAJar said:
Summary:: Is anything in the physical universe unlimited or just in math?

Is anything in the physical universe unlimited or infinite or does Infinity only exist to make some math work? Is Infinity a real thing outside of math?
Well, infinite basically means no limit. Empty space or void that is totally devoid of everything has no limit. So, there you go. But empty space that is totally devoid of everything is just hypothetical. If empty space is nothing more than the totality of electrons, then this is another example of infinite in the real world.
 
  • #77
@wonderingchicken:

To see a World in a Grain of Sand
And a Heaven in a Wild Flower
Hold Infinity in the palm of your hand
And Eternity in an hour...


The meaning of any word has no absolute applicability. There needs to be agreement—an applicable lexicon. Words require a full context. One way to think of infinity in Math is to divide 1 by zero... that is an infinity but can any human mind fully grasp what it means? The result of this division is a number bigger than any human mind can comprehend or ever write down—it size may be approached—but adding a single digit makes it 10 times bigger than before... without any limits, a number raised literally to infinity in tenfold steps, yet it is so easy to write this as a 'simple' fraction... to comprehend it is quite another thing entirely.

Saying something has no limit is also 'highly qualifiable'. You said "infinite basically means no limit". If I said you could run away with 'no limit'... would you get to infinity? It is conceivable that the further away you escape to, the closer you will be to where you first left because our Universe may be unbounded yet finite like a bug caught on the inside of an inflated balloon, it can walk forever but never reach infinity, actually it can't even get out to a distance greater than the size of the balloon. The surface of the Earth is like this—unbounded yet finite (only curved in the opposite direction). Like bugs... we live in 'Plato's Cave' with bodies formed in & by that environment. There are limits to what is directly seen.

Being totally devoid of anything is not infinity—it is a zero. "If empty space is nothing more than the totality of electrons, then this is another example of infinite in the real world". We are in fundamental disagreement about the use of the word 'electrons' being equated to 'empty space' & 'infinite'. Space being empty of everything... what is the difference between infinity & zero? You must tell me... first!
 
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  • #78
Good Elf said:
@wonderingchicken:

To see a World in a Grain of Sand
And a Heaven in a Wild Flower
Hold Infinity in the palm of your hand
And Eternity in an hour...


The meaning of any word has no absolute applicability. There needs to be agreement—an applicable lexicon. Words require a full context. One way to think of infinity in Math is to divide 1 by zero... that is an infinity but can any human mind fully grasp what it means? The result of this division is a number bigger than any human mind can comprehend or ever write down—it size may be approached—but adding a single digit makes it 10 times bigger than before... without any limits, a number raised literally to infinity in tenfold steps, yet it is so easy to write this as a 'simple' fraction... to comprehend it is quite another thing entirely.

Saying something has no limit is also 'highly qualifiable'. You said "infinite basically means no limit". If I said you could run away with 'no limit'... would you get to infinity? It is conceivable that the further away you escape to, the closer you will be to where you first left because our Universe may be unbounded yet finite like a bug caught on the inside of an inflated balloon, it can walk forever but never reach infinity, actually it can't even get out to a distance greater than the size of the balloon. The surface of the Earth is like this—unbounded yet finite (only curved in the opposite direction). Like bugs... we live in 'Plato's Cave' with bodies formed in & by that environment. There are limits to what is directly seen.

Being totally devoid of anything is not infinity—it is a zero. "If empty space is nothing more than the totality of electrons, then this is another example of infinite in the real world". We are in fundamental disagreement about the use of the word 'electrons' being equated to 'empty space' & 'infinite'. Space being empty of everything... what is the difference between infinity & zero? You must tell me... first!
Both zero and infinity are the same if you're a critical thinker. Both possessed no limits at all. What you're trying to tell me is incessant or nonstop moving such as like an ant walking incessantly on a ball. People confused unbounded part of the "finite but unbounded universe" hypothesis with incessant motion on something.
 
  • #79
Good Elf said:
One way to think of infinity in Math is to divide 1 by zero... that is an infinity but can any human mind fully grasp what it means? The result of this division is a number bigger than any human mind can comprehend or ever write down—it size may be approached—but adding a single digit makes it 10 times bigger than before... without any limits, a number raised literally to infinity in tenfold steps, yet it is so easy to write this as a 'simple' fraction... to comprehend it is quite another thing entirely.
Although it may sound poetical to say that no one understands mathematics, it's not the case. The mathematics of infinite sets is well understood by any competent mathematics student.
 
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  • #80
Time to close this thread. Thanks to all that have participated.
 

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