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Related papers: The Separation of $NP$ and $PSPACE$

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A set is autoreducible if it can be reduced to itself by a Turing machine that does not ask its own input to the oracle. We use autoreducibility to separate the polynomial-time hierarchy from polynomial space by showing that all…

Logic · Mathematics 2016-09-07 Harry Buhrman , Lance Fortnow , Leen Torenvliet , Dieter van Melkebeek

Schindler recently addressed two versions of the question P $\stackrel{?}{=}$ NP for Turing machines running in transfinite ordinal time. These versions differ in their definition of input length. The corresponding complexity classes are…

Logic · Mathematics 2007-05-23 Vinay Deolalikar

While theoretical computer science primarily works with discrete models of computation, like the Turing machine and the wordRAM, there are many scenarios in which introducing real computation models is more adequate. We want to compare real…

Computational Complexity · Computer Science 2025-10-08 Thekla Hamm , Lucas Meijer , Tillmann Miltzow , Subhasree Patro

The class of local languages is a well-known subclass of the regular languages that admits many equivalent characterizations. In this short note we establish the PSPACE-completeness of the problem of determining, given as input a…

Formal Languages and Automata Theory · Computer Science 2025-11-11 Antoine Amarilli , Mikaël Monet , Rémi De Pretto

Complexity classes such as $\#\mathbf{P}$, $\oplus\mathbf{P}$, $\mathbf{GapP}$, $\mathbf{OptP}$, $\mathbf{NPMV}$, or the class of fuzzy languages realised by polynomial-time fuzzy nondeterministic Turing machines, can all be described in…

Formal Languages and Automata Theory · Computer Science 2024-08-20 Peter Kostolányi

The notion of nondeterminism has disappeared from the current definition of NP, which has led to ambiguities in understanding NP, and caused fundamental difficulties in studying the relation P versus NP. In this paper, we question the…

Computational Complexity · Computer Science 2015-01-09 Yu Li

We introduce a new setting, the category of $\omega$PAP spaces, for reasoning denotationally about expressive differentiable and probabilistic programming languages. Our semantics is general enough to assign meanings to most practical…

Programming Languages · Computer Science 2023-05-29 Mathieu Huot , Alexander K. Lew , Vikash K. Mansinghka , Sam Staton

It is known [DemriSchnoebelen02] that both satisfiability and model-checking problems for propositional Linear-time Temporal Logic, LTL, with only a single propositional variable in the language are PSPACE-complete, which coincides with the…

Logic in Computer Science · Computer Science 2018-11-27 Mikhail Rybakov , Dmitry Shkatov

The objective of this article is to formalize the definition of NP problems. We construct a mathematical model of discrete problems as independence systems with weighted elements. We introduce two auxiliary sets that characterize the…

Data Structures and Algorithms · Computer Science 2007-05-23 Anatoly D. Plotnikov

In P systems with active membranes, the question of understanding the power of non-confluence within a polynomial time bound is still an open problem. It is known that, for shallow P systems, that is, with only one level of nesting,…

Computational Complexity · Computer Science 2020-08-05 Alberto Leporati , Luca Manzoni , Giancarlo Mauri , Antonio E. Porreca , Claudio Zandron

We provide an implicit characterization of polynomial time computation in terms of ordinary differential equations: we characterize the class $\operatorname{PTIME}$ of languages computable in polynomial time in terms of differential…

Computational Complexity · Computer Science 2017-01-18 Olivier Bournez , Daniel S. Graça , Amaury Pouly

We introduce a novel variant of BSS machines called Separate Branching BSS machines (S-BSS in short) and develop a Fagin-type logical characterisation for languages decidable in non-deterministic polynomial time by S-BSS machines. We show…

Logic in Computer Science · Computer Science 2020-07-09 Miika Hannula , Juha Kontinen , Jan Van den Bussche , Jonni Virtema

It is well known that the kind of P systems involved in the definition of the P conjecture is able to solve problems in the complexity class $\mathbf{P}$ by leveraging the uniformity condition. Here we show that these systems are indeed…

Computational Complexity · Computer Science 2020-08-05 Alberto Leporati , Luca Manzoni , Giancarlo Mauri , Antonio E. Porreca , Claudio Zandron

The question of whether all problems in NP class are also in P class is generally considered one of the most important open questions in mathematics and theoretical computer science as it has far-reaching consequences to other problems in…

Data Structures and Algorithms · Computer Science 2016-12-20 Wenhong Tian

There are languages A such that there is a Pushdown Automata (PDA) that recognizes A which is much smaller than any Deterministic Pushdown Automata (DPDA) that recognizes A. There are languages A such that there is a Linear Bounded Automata…

Formal Languages and Automata Theory · Computer Science 2015-07-17 Richard Beigel , William Gasarch

An important theorem in classical complexity theory is that LOGLOGSPACE=REG, i.e. that languages decidable with double-logarithmic space bound are regular. We consider a transfinite analogue of this theorem. To this end, we introduce…

Logic · Mathematics 2026-05-19 Merlin Carl

Article presents the compatibility matrix method and illustrates it with the application to P vs NP problem. The method is a generalization of descriptive geometry: in the method, we draft problems and solve them utilizing the image…

Computational Complexity · Computer Science 2012-05-08 Sergey Gubin

We investigate the possibility to separate the bisimulation-invariant fragment of P from that of NP, resp. PSPACE. We build on Otto's Theorem stating that the bisimulation-invariant queries in P are exactly those that are definable in the…

Logic in Computer Science · Computer Science 2026-01-28 Florian Bruse , Martin Lange

This paper presents the following results on sets that are complete for NP. 1. If there is a problem in NP that requires exponential time at almost all lengths, then every many-one NP-complete set is complete under length-increasing…

Computational Complexity · Computer Science 2010-02-03 Xiaoyang Gu , John M. Hitchcock , A. Pavan

Neural Laplace is a unified framework for learning diverse classes of differential equations (DE). For different classes of DE, this framework outperforms other approaches relying on neural networks that aim to learn classes of ordinary…

Machine Learning · Computer Science 2024-06-10 Adrien Carrel