# What is empty space ?

#### curioussoul09

What is "empty space"?

I always hear this term: "empty space." It is synonymous with "vacuum," but I am having trouble understanding either of these two ideas.

How can space be "empty?"

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#### tiny-tim

Homework Helper
I always hear this term: "empty space." It is synonymous with "vacuum," but I am having trouble understanding either of these two ideas.

How can space be "empty?"
that's the pessimist view

I think that space is full, of …

well …

space!

#### wolram

Gold Member
Re: What is "empty space"?

I would think it is impossible to have a truly empty space.

Edit

How would one find it?

#### Bob S

Re: What is "empty space"?

The permeability of empty space is u0 Henrys per meter, and the permittivity of empty space is e0 Farads per meter, so the impedance of empty space is sqrt(u0 / e0)) = 377 ohms, and the velocity of light is sqrt(1 /(u0 e0)) = 2.9979 x 108 meters per sec. Other than that its pretty much nothing at all (except dark matter, dark energy, neutrinos, cosmic rays, microwaves, gravity, photons, etc.)

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#### Danger

Gold Member
Re: What is "empty space"?

Other than that its pretty much nothing at all (except dark matter, dark energy, neutrinos, cosmic rays, microwaves, gravity, photons, etc.)
You can add the collective intellect of my in-laws to that list... :grumpy:

#### cragar

Re: What is "empty space"?

higgs field

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