Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Totally Secure Classical Communication Utilizing Johnson (-like) Noise
  and Kirchoff's Law   An absolutely secure, fast, inexpensive, robust, maintenance-free and
low-power- consumption communication is proposed. The states of the information
bit are represented by two resistance values. The sender and the receiver have
such resistors available and they randomly select and connect one of them to
the channel at the beginning of each clock period. The thermal noise voltage
and current can be observed but Kirchoff's law provides only a second-order
equation. A secure bit is communicated when the actual resistance values at the
sender's side and the receiver's side differ. Then the second order equation
yields the two resistance values but the eavesdropper is unable to determine
the actual locations of the resistors and to find out the state of the sender's
bit. The receiver knows that the sender has the inverse of his bit, similarly
to quantum entanglement. The eavesdropper can decode the message if, for each
bits, she inject current in the wire and measures the voltage change and the
current changes in the two directions. However, in this way she gets discovered
by the very first bit she decodes. Instead of thermal noise, proper external
noise generators should be used when the communication is not aimed to be
stealth.

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The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
8
The categories of this paper are: hep-ex
11
The categories of this paper are: hep-lat
26
The categories of this paper are: bayes-an
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The categories of this paper are: dg-ga
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
9
The categories of this paper are: nlin
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The categories of this paper are: comp-gas
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The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int