,
Prashant Nalini Vasudevan
Creative Commons Attribution 4.0 International license
Given an integer-valued function f:{0,1}ⁿ → {0,1,… , m-1} that is mildly hard to compute on instances drawn from some distribution D over {0,1}ⁿ, we show that the function g(x_1, … , x_t) = f(x_1) + ⋯ + f(x_t) is strongly hard to compute on instances (x_1,… ,x_t) drawn from the product distribution D^t. We also show the same for the task of approximately computing real-valued functions f:{0,1}ⁿ → [0,m). Our theorems immediately imply hardness self-amplification for several natural problems including Max-Clique and Max-SAT, Approximate #SAT, Entropy Estimation, etc..
@InProceedings{li_et_al:LIPIcs.CCC.2025.2,
author = {Li, Yunqi and Vasudevan, Prashant Nalini},
title = {{Hardness Amplification for Real-Valued Functions}},
booktitle = {40th Computational Complexity Conference (CCC 2025)},
pages = {2:1--2:25},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-379-9},
ISSN = {1868-8969},
year = {2025},
volume = {339},
editor = {Srinivasan, Srikanth},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.CCC.2025.2},
URN = {urn:nbn:de:0030-drops-236967},
doi = {10.4230/LIPIcs.CCC.2025.2},
annote = {Keywords: Average-case complexity, hardness amplification}
}