[benm (OP)]

Dalton has a question about quantum entanglement

Why aren't we looking for advanced communication systems that employ entangled particles and don't suffer from the inverse square law? It has to be nearly impossible to filter out the background noise in RF, whereas it could be very possible to generate wave lengths of light that are not part of a solar spectra and easily separated from the ambient light generated and scattered throughout space (prisms and diffraction grating)

Can any help untangle this one?

[Bored chemist]

... don't suffer from the inverse square law?

We already did.
That's why we use optical fibres for comms.

[evan_au]

advanced communication systems that employ entangled particles

Entangled particles have already been used for generation and distribution of "unbreakable" encryption keys between two parties.

The strength and the weakness of entangled particles is that they are very "fragile" - any outside disturbance breaks the entanglement.
- If a spy tries to listen in on the entangled particles, it breaks the entanglement. So you know your communication is not secure
- If you try to transmit them over optical fiber (which has been done), any scattering in the fiber breaks the entanglement
- If you try to increase the range of the optical with an optical amplifier, it breaks the entanglement
- If you try to transmit them through the atmosphere (which has been done), any scattering in the air breaks the entanglement
- If you try to transmit them in free space (which has been done), the inverse square law means that most of the entangled photons don't make it to the receiver

So entangled photons are a very fragile communications medium, which means that a optical communication link with a capacity of 1 Gbps for 1,000km (non-entangled) only has a capacity of perhaps 1-10 bits per second of entangled photons - and very limited range (<100km).

But researchers are rapidly improving the quality of entangled-state generators, and working on improved ways to store entangled states (eg for more than microseconds). This will result in regular breaking of old records (eg China has a satellite that communicates with entangled photons); but at this point in time, communication with entangled photons have far less capacity than non-entangled photons.

See: https://en.wikipedia.org/wiki/Quantum_network#Quantum_networks_for_communication

[yor_on]

Maybe entanglements is another 'background' :)
A way of 'communication' if you like

But it doesn't communicate inside 'time'
Your 'clock' is yours, and mine is mine.

When we SpaceTime creatures communicate we do it inside 'c'.
And thinking of it I would call that 'meaningful communication'

Because it is.
To us

[yor_on]

If you think that way you have to ask yourself what 'time' is.