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What Is Space?

nautil.us

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Re: What Is Space?

#101

Post by monort »

sillysaurus3 wrote: post #53
Razengan wrote: post #16

Some related questions that I don't know where, or how, to ask: - Is there a “quantum” of space? Where/how is location stored? - If electromagnetic repulsion is what makes matter “take space”, and if virtually all macroscopic phenomena are governed by electromagnetism and gravity, then could this reality be said to be “gravelectromagnetic”, and might there be other “dimensions” governed by other forces, like “cones”…

Could gravity be the result of space trying to deflate/return to the pre-Big Bang singularity, kind of like pulling magnets apart? i.e. is gravity the “opposite” of, or a reaction to, “space?” I may be off the mark with what you believe, but just in case: It's a common misconception that the big bang originated at a specific point. The big bang seems to have happened everywhere simultaneously, so it wouldn't be true…

This only applies if the universe is infinite. We don't know it for sure, though we have a lower bound of the universe size at 250 Hubble volumes: http://onlinelibrary.wiley.com/doi/10.1111/j.1745-3933.2011....

And infinite universe brings strange phenomenons, like our doppelgangers far away, that are exactly like us.

Re: What Is Space?

#102

Post by zecg »

Razengan wrote: post #16

Some related questions that I don't know where, or how, to ask: - Is there a “quantum” of space? Where/how is location stored? - If electromagnetic repulsion is what makes matter “take space”, and if virtually all macroscopic phenomena are governed by electromagnetism and gravity, then could this reality be said to be “gravelectromagnetic”, and might there be other “dimensions” governed by other forces, like “cones”…

I can recommend this: https://www.goodreads.com/book/show/30201328-reality-is-not-...

Re: What Is Space?

#103

Post by michaelscott »

Razengan wrote: post #58
tombh wrote: post #32

Earlier quoted context omitted.

Nothing to add, I just love where your questions send my mind, thank you.

You may enjoy contemplating a sort of "epiphany" that I had during that usual pondering of imponderables: That the default or base state of existence may not be nothing, not "not even nothing", but rather Everything. ... Instead of viewing the origin of all reality/creation as things being added to a canvas of blackness/emptiness/voidness, rather consider that "Existence" may be a subtractive process: akin to holes b…

I recently had a somewhat tangential conversation with someone, wherein the relationship between order and chaos in the universe (and specifically our case as the human race) is a function of increasing time. Humans attempt to create order from the chaotic environment, not creating more complex things in the process but simply refining what already exists (although there seem to be unavoidable patterns of "order" that recur in the universe regardless of us or any advanced organism).

This certainly fits with the idea that the universe is an attempted "ordering" bubble in a liquid of everything

Re: What Is Space?

#105

Post by cyphar »

mschwaig wrote: post #64
gizmo686 wrote: post #5

Earlier quoted context omitted.

The biggest issue I see with the goo metaphor, is that it seems to suggest some sort of stationary ether that we move through as we move through space. That is to say, the mathaphor suggests that it makes sense to differentiate between stationary objects and moving objects in an objective sense. However, the core insight of relativity is that there is no such distinction.

I'm reading the whole book right now and the chapter after the one from the article is about time and goes more into spacetime according to relativity. So far it seems to me that they sometimes provide an oversimplified analogy which they revise in a later chapter.

> So far it seems to me that they sometimes provide an oversimplified analogy which they revise in a later chapter.

Welcome to every high-school, undergrad and postgrad physics course. That's just how most sciences are taught. Physics especially, because all analogies lead to misunderstandings because they are an attempt to simplify the mathematics underlying the physics[1]. Such analogies will always result in certain subtleties being lost on the student, but if the student is not familiar with the subject then the mathematics would also be lost on them.

The reason why this method works is that physics operates on approximations, so an approximately accurate analogy is a step in the right direction for a more accurate mathematical model (which is still ultimately an approximation).

[1]: https://xkcd.com/895/

Re: What Is Space?

#106

Post by peter303 »

Razengan wrote: post #16

Some related questions that I don't know where, or how, to ask: - Is there a “quantum” of space? Where/how is location stored? - If electromagnetic repulsion is what makes matter “take space”, and if virtually all macroscopic phenomena are governed by electromagnetism and gravity, then could this reality be said to be “gravelectromagnetic”, and might there be other “dimensions” governed by other forces, like “cones”…

Plancks quantum of action says there a minimum length of space 10^-35 meters below which no experiment can measure. Some asume this is a quantum of space, but not necessarily so. Some physicists suggest the universe is very strange at this length scale and may a sea of boiling virtual particles.

Re: What Is Space?

#107

Post by peter303 »

basicplus2 wrote: post #10

Maybe space is the ether afterall

Ether was invoked the structure of space was necessary for fields to propagate, e.g. light was a vibration of space. This is no longer necessary. And could not be detected in the M-M experiment.

The Ionian Greeks proposed most of same models of space as modern physics, but lacked experiments to select the correct model. Some model propes emptiness and others an underlying substance of matter or energy.

Re: What Is Space?

#108

Post by zdkl »

lmm wrote: post #95
ravenstine wrote: post #2

I'm simultaneously glad that someone's writing articles about these things and dismayed that too many people will read this and believe they understand astrophysics without having philosophized about it on their own. Analogies like "space goo" are useful but can be a double-edged sword(seems the author recognizes this) that can mislead the public in much the same way that the holographic universe theory leads the pub…

Lack of philosophizing is less of an issue than ignorance of the physics, even - especially - among philosophers. There ought to be a rule against speculating on the nature of reality in the context of quantum physics if you haven't completed the exercises in Nielsen and Chuang.

There ought to be a rule against people making rules not founded in maths.

Re: What Is Space?

#109

Post by lmm »

graycat wrote: post #59
cyphar wrote: post #54

Earlier quoted context omitted.

But I don't understand how the question "what is the purpose of X" can be anything but philosophical. Science is primarily concerned with creating models of reality and testing the predictive power of those models. The "purpose" of something is not really a meaningful concept in that context. ... unless by "purpose" you mean cause? As in, what caused our universe to exist? That is also not really a meaningful questio…

> But I don't understand how the question "what is the purpose of X" can be anything but philosophical. Again, my guess is that this depends on how much we know. Or, there about has to be a purpose. And eventually as we learn more there should be some clues about what that purpose is. So I'm wondering if we know that much yet? A first little clue is the speed of light speed limit that so far seems to say that we are…

> Or, if there is no purpose, then this is one heck of a big show for nothing!

It isn't really. The universe all falls out of a very few, very simple rules playing themselves out - and the more we study it the smaller and simpler that set of basic rules is. Physically it's pretty big, sure, but the Kolgomorov Complexity is actually pretty small, and that's the kind of measure you need to use when considering how good a given explanation is.

Re: What Is Space?

#110

Post by anentropic »

jsmthrowaway wrote: post #74
Razengan wrote: post #58

Earlier quoted context omitted.

You may enjoy contemplating a sort of "epiphany" that I had during that usual pondering of imponderables: That the default or base state of existence may not be nothing, not "not even nothing", but rather Everything. ... Instead of viewing the origin of all reality/creation as things being added to a canvas of blackness/emptiness/voidness, rather consider that "Existence" may be a subtractive process: akin to holes b…

This is a common theme many human societies and cultures have developed, and it makes a lot of sense when you really (really) think about it. When you take it further, you realize that also implies everything being connected fundamentally, which is an another interesting thought space to explore with a litany of deep implications, particularly around consciousness.

it doesn't obviously imply anything to do with consciousness
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