The cr.yp.to microblog: 2018.03.14 23:50:02

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?

Context

2018.03.14 10:13:06 (973855630183235584) from "Jonathan Oppenheim (@postquantum)":

Security hole in quantum cryptography discovered! If an eavesdropper has an exact copy of the entire universe and Alice and Bob have no free will, then she can figure out their secret! Almost as easy as pretending to be tech support and asking them for their password.

2018.03.14 11:13:25 (973864671856996352) from "Māris Ozols (@enclanglement)", replying to "Jonathan Oppenheim (@postquantum)" (973855630183235584):

Unless the eavesdropper is part of an even larger universe controlled by the almighty space aliens! (The quote below is from page 8 of the paper.)

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.