The microblog: 2018.03.15 20:40:23

2018.03.15 20:40:23 (974369739337322496) from Daniel J. Bernstein, replying to "Jonathan Oppenheim (@postquantum)" (974268961650077697):

Mathematically, what do you mean with your claim that Faraday cages "cancel" EM waves? (I think you're massively confused, and focusing on the Faraday-cage example will help pinpoint the source of confusion.)


2018.03.14 11:24:25 (973867436796674051) from "Māris Ozols (@enclanglement)", replying to "Māris Ozols (@enclanglement)" (973864671856996352):

More seriously, given that all current attacks on QKD exploit imperfections / side-channels, isn't it a worthwhile theoretical question to understand the trade-off for such attacks? His main point is that we as theoreticians are dismissing the very existence of such trade-off.

2018.03.14 12:27:38 (973883345800253440) from "Jonathan Oppenheim (@postquantum)", replying to "Māris Ozols (@enclanglement)" (973867436796674051):

He's talking about lab security and many people have discussed attacks which aim to get inside Alice and Bob's lab. Great. But saying that a Faraday cage "merely applies some scrambling to the signals" or invoking Holography leads to far less plausible attacks.

2018.03.14 23:50:02 (974055080562429958) from Daniel J. Bernstein, replying to "Jonathan Oppenheim (@postquantum)" (973883345800253440):

Let me get this straight. Are you claiming that Faraday cages have a security property guaranteed by the laws of physics? If so, what precisely do you claim that this security property is?

2018.03.15 13:59:56 (974268961650077697) from "Jonathan Oppenheim (@postquantum)":

Hi Daniel, I think it leaves an incorrect impression to say a Faraday cage merely scrambles information. They cancel EM waves, and I'm not aware of any fundamental limitation on that, especially if all you're trying to shield is which fiber-optic cable a photon travelled down. 1/