Infinity exists in math, but can't in nature?

[Baby Astronaut]

What's the highest limit in numbers that we're able to count? Or the lowest (negatives?).

 

Exactly.

 

Infinities are supposed to reveal a problem with a theory. But infinities do exist. In counting of numbers, in light wavelengths, and in the measure of gravity strength. (...to name a few?)

 

Does anyone know the problem with infinities, how that got started, and who decided it's a problem?

[Mr Skeptic]

I never use infinities, I take limits to infinities. Infinity just means as big as you like.

[ajb]

Infinities are found in the mathematical formulations of physical theories. Sometimes, such as in renormalisation theory they can be handled. However, more generally as you say they are treated as a symptom of a theory being used outside the domain of validity. This is a good thing as you are lead to new physics.

 

The infinities you point to are mathematical in nature and not physical.

 

It is generally believed that no measurable quantity in nature can be physically measured to have an infinite value. Or, put another way we can only measure real numbers and as infinity is not a number we can never observe infinity in our experiments.

 

The first "infinity" I am aware of is the classical electron self-energy. In classical electromagnetism you can calculate the energy needed to "assemble" an electron. You find that it is infinite! Yet, electrons exist.

 

The solution to this problem let to quantum field theory. The quantum corrections to the self-energy are themselves infinite. However, these corrections are such that overall calculation gives a finite answer.

[darkenlighten]

I concur with ajb.

 

Everything can be quantized, including waves, down to packets of waves (photons). It's essentially what Quantum Mechanics is based off of. Everything has a definite, finite amount.

[liarliarpof]

Good! If infinities in nature are disregarded, we can begin to clean house. For starters, let's toss the 'multiverse' speculation and continue from there.

[ajb]

Good! If infinities in nature are disregarded, we can begin to clean house. For starters, let's toss the 'multiverse' speculation and continue from there.

 

Simply put, as we cannot measure there to be an infinite number of them (if that is the claim) there is no problem. But then, the issue of what it means to "exist".

[Sorcerer]

Without even reading anyting except your title, it depends on your definition of exists. OK, now to read...

 

lol..... but how can we know what we cannot measure?

[ajb]

..... but how can we know what we cannot measure?

 

Indeed.

[Baby Astronaut]

But we can measure a number beyond the calculated total energy of the universe

[clemzzz]

Good! If infinities in nature are disregarded, we can begin to clean house. For starters, let's toss the 'multiverse' speculation and continue from there.

 

Exactly!

it beggars belief why anyone would bother with the multiverse idea!

Infinite universes would mean one of the universes is capable of engulfing all the other universes , making all the other universes destroyed ,infact there would be an infinite number of superdestructive universes destroying all the infinite others or there could be an infinite number of universes with super technological mega beings travelling to all the universes and destroying everything in their path , there's just an infinite possibilty of ludicrous situations.

They like to point out that it could explain the laws of physics in our universe but they just haven't thought about it to even the level of a childs thinking.