bip52: Update to Closed

This proposal appears abandoned, as it has not had any updates in over
four years, and cursory search did not produce any public discussions of
it since it was published either. Attempts to contact the authors did
not receive a response within four weeks.

README.mediawiki

@@ -302,13 +302,13 @@ users (see also: [https://en.bitcoin.it/wiki/Economic_majority economic majority
 | Gavin Andresen
 | Informational
 | Deployed
-|-
+|- style="background-color: #ffcfcf"
 | [[bip-0052.mediawiki|52]]
 | Consensus (hard fork)
 | Durable, Low Energy Bitcoin PoW
 | Michael Dubrovsky, Bogdan Penkovsky
 | Specification
-| Draft
+| Closed
 |-
 | [[bip-0053.mediawiki|53]]
 | Consensus (soft fork)

bip-0052.mediawiki

@@ -4,7 +4,7 @@
   Title: Durable, Low Energy Bitcoin PoW
   Authors: Michael Dubrovsky <mike+bip@powx.org>
            Bogdan Penkovsky <bogdan+bip@powx.org>
-  Status: Draft
+  Status: Closed
   Type: Specification
   Assigned: 2021-05-13
   License: BSD-2-Clause OR OPUBL-1.0
@@ -284,13 +284,15 @@ With significant progress in optical and analog matrix-vector-multiplication chi
 
 PoWx will also be publishing the designs of the current optical miner prototypes in the near term under an open-source hardware license.
 
+== Changelog ==
+
+* 2026-06-18:
+** Updated to Closed after the proposal has not made progress for several years and [https://groups.google.com/g/bitcoindev/c/Vrh7oED9b9Q/m/TrCEKRjNAAAJ attempts to contact the authors] did not succeed.
+
 == Acknowledgments ==
 
 We thank all the members of the Bitcoin community who have already given us feedback over the last several years as well as others in the optical computing community and beyond that have given their input.
 
-
-
-
 [1] M. Dubrovsky et al. Towards Optical Proof of Work, CES conference (2020) https://assets.pubpub.org/xi9h9rps/01581688887859.pdf
 
 [2] https://sciencex.com/news/2020-05-powering-bitcoin-silicon-photonics-power.html