Can someone explain quantum communications

[mr friendly guy]

Ok I get that quantum communications is supposed to be more secure and "hack proof" than what we have now. Numerous countries are working on it. I understand that it uses Heisenberg's uncertainty principle as part of what makes it work, and if a hacker tried to view the message it would cause the message to be destroyed. Can someone explain to me in simple terms.

a. How the message is destroyed if a hacker tries looking at it

b. Why doesn't the intended recipient of the message have the same problem of the message being destroyed when they look at the message

c. Does the fact the message gets destroyed when an unauthorised party attempts to look at it, not make quantum communications vulnerable to jamming by said unauthorised party. To elaborate the unauthorised party may have no intention of looking at the message per se, but just interested in denying the intended recipient the ability to read it and attempts to read the message purely so it gets destroyed.

[Grumman]

My understanding of quantum communications might be incorrect, but as I understand it...

a. How the message is destroyed if a hacker tries looking at it

b. Why doesn't the intended recipient of the message have the same problem of the message being destroyed when they look at the message

The act of encoding information in the entangled pair produces classical information - a brand new one-time pad, basically. If you have that classical information, you can use it to decode the information in the entangled pair.

c. Does the fact the message gets destroyed when an unauthorised party attempts to look at it, not make quantum communications vulnerable to jamming by said unauthorised party. To elaborate the unauthorised party may have no intention of looking at the message per se, but just interested in denying the intended recipient the ability to read it and attempts to read the message purely so it gets destroyed.

If the enemy has access to the receiver, they can render them incapable of decoding the message. But that is trivially true of any form of secure communication - it doesn't matter if your flash drive is encrypted if all they want to do is smash it with a baseball bat. Intercepting the classical information is, I believe, insufficient to render the information inaccessible - as classical information, there's nothing stopping you from simply copying it and resending it.

[Jaepheth]