# How to measure empty space

#### sushi

##### Well-Known Member
how do you measure amount of space/nothingness,

is it quantifiable or unquantifialbe
what parameter can be used?

for example: how to measure the amount of "space" in the sky?

do standard measurements like mass, volume, energy, pressure, distance, area apply to this

standardized measurements is one of the things that gave birth to modern science, so I am thinking if empty space or void has amount or quantity that is measurable.

is the amount of empty space in an empty room equal to the room's volume, or is it something else?

#### elliptoid

##### the void is a lie
Good question!

To start make sure you are familiar with the Planck Length and then move onto mass-energy equivalence and uncertainty. At least have a layperson understanding of these entry level principles.

Then yes your answer is most certainly area or volume depending on the dimensionality of the projection you're using.

Measuring astronomical distances is very intricate and exciting process too. Learn about the parsec to understand more.

#### sushi

##### Well-Known Member
Good question!

To start make sure you are familiar with the Planck Length and then move onto mass-energy equivalence and uncertainty. At least have a layperson understanding of these entry level principles.

Then yes your answer is most certainly area or volume depending on the dimensionality of the projection you're using.

Measuring astronomical distances is very intricate and exciting process too. Learn about the parsec to understand more.
let me think about that and do some research.

Is mass, energy, volume, distance, area not applicable in measuring space and nothing?

#### QuickTwist

##### Spiritual "Woo"
You can't measure space in a vacuum. You have to measure it in relation to objects that fill up that space. You have to have a total space amount and then find the area for the objects within that space and then subtract from the total space. At least this is what makes sense to me, but I might not really know what you are asking.

#### sushi

##### Well-Known Member
You can't measure space in a vacuum. You have to measure it in relation to objects that fill up that space. You have to have a total space amount and then find the area for the objects within that space and then subtract from the total space. At least this is what makes sense to me, but I might not really know what you are asking.
you just say the exact opposite of what i mean.

if you can't measure how much black space and emptiness, how can the amount of empty space in the universe be measured?

#### Minute Squirrel

##### magician
I imagine it would depend on what kind of empty space you are talking about. If we're using the room example then it would be relayed terms volume. But ultimately I don't think we can measure it directly as our current understanding is that things fill empty space which is infinite. The universe is filling up empty space but there's still empty space inside it. Like if a jar would suddenly appear it would fill up an empty space while still having an empty space inside it as well.

#### Serac

##### A menacing post slithers
Just figure out the geometry of the space (e.g. Euclidean) and take measurements along its dimensions. Don't really see the problem.

#### kanteravir

##### Redshirt
Space is never entirely empty. Different patches of empty space can be measured to have a different energy density.
Is mass, energy, volume, distance, area not applicable in measuring space and nothing?
Space can be measured for existence of those properties, or their lack.

-How much space lacks energy defines how much of the energy can still fit inside of it, same with mass. Mass is non-linearly proportional to energy.
-Volume and area are directly proportional to distance. The relation is cubic and quadratic respectively. Or you could think in terms of diagonals, square roots of 3 and 2.
-Each unit of space can hold a finite amount of mass-energy ratio which is its energy density.

Space is something which can have properties, emptiness is the local value of those properties and to get a perception of the magnitude of the observed properties some places in space need to be different from others and compared against.

#### sushi

##### Well-Known Member
i now define space as the amount of "stuff/void" between two positions (cordinates).
if the amount of stuff is between two position is zero, than space= 0 .

can anyone define what space is?

#### The Grey Man

##### Well-Known Member
Lots of people with big brains have tried, with mixed success.

There are mainly two schools of thought: the realistic school, typified by Newton, which says that space is the unbounded container of all natural objects whatsoever; and the idealistic school, represented by Leibniz, which says that space as the sum of the relations of distance between those objects.

Kant manages to be both a realist and an idealist regarding space by equivocating on what space is (his heroic determination to publish his doctrine before his weak constitution became his undoing apparently could not make him into a good writer, much to the exasperation of every philosopher who has tried to continue his work). In the first part of his principal epistemological work, he calls space a pure form of perception in which all objects are contained, as Newton said, but in another part he calls it the synthesis of the manifold provided by the sensibility, which sounds more like Leibniz.

I think that the question of whether objects are in space or space connects objects is undecidable, inevitably resulting in Kant calls an "antinomy," a situation in which two contradictory theses are equally defensible. This neatly explains why three big brains could believe the one thesis, the other, and both. Matter is no accident of form, nor form of matter, but both are complementary aspects of the same thing.

#### sushi

##### Well-Known Member
Lots of people with big brains have tried, with mixed success.

There are mainly two schools of thought: the realistic school, typified by Newton, which says that space is the unbounded container of all natural objects whatsoever; and the idealistic school, represented by Leibniz, which says that space as the sum of the relations of distance between those objects.

Kant manages to be both a realist and an idealist regarding space by equivocating on what space is (his heroic determination to publish his doctrine before his weak constitution became his undoing apparently could not make him into a good writer, much to the exasperation of every philosopher who has tried to continue his work). In the first part of his principal epistemological work, he calls space a pure form of perception in which all objects are contained, as Newton said, but in another part he calls it the synthesis of the manifold provided by the sensibility, which sounds more like Leibniz.

I think that the question of whether objects are in space or space connects objects is undecidable, inevitably resulting in Kant calls an "antinomy," a situation in which two contradictory theses are equally defensible. This neatly explains why three big brains could believe the one thesis, the other, and both. Matter is no accident of form, nor form of matter, but both are complementary aspects of the same thing.
I need to study what they wrote more. It seems to the past philosphers like kant and newton already try to define it.

i want to know whether space is really shapeless and formless, or does it have specific shape area or form.

#### travelnjones

##### Active Member
If you are talking about the Mass Energy universe I would say time. Though degradation (red shift) of frequency would be similar. This assumes a finite yet unbound system and that constant is constant. As to density there is variation dependent on proximity to stars. I have heard that measured in molecules per cubic foot.

#### Pizzabeak

##### Prolific Member
Reality is made out of language and meaning, although the scientific models still describe things (phenomena) pretty well. We have the concept of vacuum, which is similar to the Eastern concept of void (non-scientific term, more spiritual or philosophical than anything else). It can be quantified in either energy density or gravitational potential. Exotic matter (dark or non-baryonic matter) could complicate it more these days, since when I was a kid over twenty years ago we didn't really know what it is. You would still be able to measure a vacuum, though.

Measuring the amount of space in the sky is really only important to specialists in the field of cosmology. You could very well take the masses of galaxies and approximate the empty space in between, including subatomic and virtual particles such as neutrinos and gravitons or anti-matter, and anything giving off friction as energy adds to the total of all that.

We know some of the shape of space because of the cosmic microwave background radiation, which is a notion that supports the Big Bang. The variation in spatial density indicates non homogeneity, or the result of the cooling of extremely hot, plasma temperatures, based on the initial settings of the universe.

Leibniz had a more philosophical approach to space whereas Newton solidified the science aspect of it. We know that Newton laid the foundations of absolute space down in the late 17th century before Einstein updated it, saying it is relative, in 1905-1915. Leibniz said it was spatially relational, which sounds relative, and this is the aspect people talk about when they say Einstein plagiarized relativity.

Absolute or relative space could mean everything is one. According to Leibniz, if space consists of relational points between objects, God would have had to think where to put the universe, as opposed to any other location. How important would that be? The opposite would be that it wouldn't so much matter, if there was no direction in space, any other place the universe in would basically be the same. We wouldn't be able to shift to a different universe.

It's illustrated in the bucket of water example, wherein if you spin it it accelerates, and the water doesn't spin until a certain velocity is reached. Space is the water and universe the bucket. Leibniz said you could move the whole bucket. Newton said the water only moves if the bucket does, and that the bucket doesn't necessarily exist.

Newton's 1st Law of Motion: Inertia - an object in motion tends to stay in motion, and one at rest tends to remain at rest, as they were, unless acted on by forces, such as friction.

2nd Law - F=ma

3rd Law - Every action has an equal and opposite reaction. In order to move a boulder, one must apply more energy to it than its mass contains.

Air is really another layer, above the ocean - it's an ocean of air that we breathe, oxygen and carbon/CO2, because we can't breathe water anymore (no gills). Space is a lack of it. We are, in a sense, still connected through that. Space could be more equilibrium in an environment. A core, planetary or stellar, is a huge mass exerting gravitational influence. It warps spacetime causing it to sink. In one sense, it's what's on the other side if any two points in space could be connected. It wouldn't be the most efficient way of transferring information, so to speak.

#### sushi

##### Well-Known Member
The question is is space shapeless, formeless and massless? the three properties that define matter and object (shape, area, form mass)

there is no deep investigation of the true nature and properties of pace and nothing is after and newton and lenbiz, although einstein sort of refrence it in aether, which he later killed.

#### sushi

##### Well-Known Member
how to define space and nothing:

we can only define space by what it includes inside, and its size and boundary.

the space inside a room is defined by all the stuff, matter energy, and emptiness included in room.

but some claim space is boundless, so i would again differentiation, bounded space, and unbounded space.