wiki_research

personal research wiki
git clone https://a3nm.net/git/wiki_research/
Log | Files | Refs

commit 073b57210df08ce39420b87bb0652bbaf28b61d0
parent 5bcd0e7a21a6454452ab535c1a81ac8180ec2bfb
Author: Antoine Amarilli <a3nm@a3nm.net>
Date:   Wed, 19 Feb 2025 12:00:21 +0100

commit with codex

Diffstat:
accepting_run | 9+++++++++
complexity_time | 2+-
fagins_theorem | 5+++++
fp | 5+++++
game_theory | 10----------
gap_p | 13+++++++++++++
integers | 2+-
maximum | 2+-
minimal_witness | 2++
npmv | 5+++++
parity_p | 2+-
partial_run | 5+++++
ptime | 2+-
rejecting_run | 9+++++++++
run | 11+++++++++++
second_order_logic | 14++++++++++++++
semiring_idempotent | 2+-
semiring_multiplicative_idempotent | 2+-
theorem | 1+
tropical_semiring | 4+++-
turing_machine | 3+++
turing_machine_deterministic | 11+++++++++++
turing_machine_nondeterministic | 4++++
turing_machine_weighted | 14++++++++++++++
viterbi_semiring | 2++
25 files changed, 123 insertions(+), 18 deletions(-)

diff --git a/accepting_run b/accepting_run @@ -0,0 +1,9 @@ +# Accepting run + +A [run] which finishes on a [final_state] + +Up: [run] + +Aliases: accepting runs + +See also: [rejecting_run] diff --git a/complexity_time b/complexity_time @@ -1,6 +1,6 @@ # Complexity time -The [asymptotic] running time of an [algorithm] +The [asymptotic] [running_time] of an [algorithm] - [complexity_time_classes] diff --git a/fagins_theorem b/fagins_theorem @@ -0,0 +1,5 @@ +# Fagin's theorem + +https://en.wikipedia.org/wiki/Fagin%27s_theorem + +Up: [theorem], [descriptive_complexity] diff --git a/fp b/fp @@ -0,0 +1,5 @@ +# FP + +The [complexity_class] of the [functions] computed by [deterministic_Turing_machines] in [polynomial_time] + +Up: [complexity_class] diff --git a/game_theory b/game_theory @@ -1,10 +0,0 @@ -# Game theory - -studies [games] - -- [shapley_value] -- [parity_games] et [pseudopolynomial]-time algorithm -- [muller_acceptance] -- [prisoners_dilemma] - -Up: [mathematics] diff --git a/gap_p b/gap_p @@ -0,0 +1,13 @@ +# GapP + +https://complexityzoo.net/Complexity_Zoo:G#gapp + +The functions that can be expressed as the [gap] of a [nondeterministic_Turing_machine], aka the difference between the number of [accepting_runs] and of [rejecting_runs] + +The closure of the [sharpP] functions under [subtraction] + +mentioned in [thierauf1994closure] for instance + +Up: [complexity_class] + +Aliases: GapP diff --git a/integers b/integers @@ -4,4 +4,4 @@ The set \mathbb{Z} of [natural_numbers] or the [negative_numbers] (including [ze Up: [number] -Aliases: integer +Aliases: integer, ZZ diff --git a/maximum b/maximum @@ -3,7 +3,7 @@ the largest [element] of an [order] - [supremum] -See also: [minimum] +See also: [minimum], [maximization_problem] Up: [mathematics_basic_concepts] diff --git a/minimal_witness b/minimal_witness @@ -1,5 +1,7 @@ # Minimal witness +#todo "minimum witness"? + Find the smallest subset of a [relational_database] that satisfies a [query] - formally, for query Q and database D, find smallest subset D' of D giving the same result - [approximation]: find a subset of tuples giving the same results which is within a [approximation_multiplicative] factor of the size of the optimal subset diff --git a/npmv b/npmv @@ -0,0 +1,5 @@ +# NPMV + +https://complexityzoo.net/Complexity_Zoo:N#npmv + +Up: [complexity_class] diff --git a/parity_p b/parity_p @@ -6,4 +6,4 @@ https://en.wikipedia.org/wiki/Parity_P Up: [parity], [complexity_class] -See also: [parity_fine_grained] +See also: [parity_fine_grained], [Z_2Z] diff --git a/partial_run b/partial_run @@ -0,0 +1,5 @@ +# Partial run + +A generalization of [runs], that only process a [prefix] of the input [word] + +Up: [run] diff --git a/ptime b/ptime @@ -13,4 +13,4 @@ Up: [complexity_class] See also: [pseudo_polynomial_time], [quasipolynomial], [oplusp], [ptime_reduction] -Aliases: P +Aliases: P, polynomial time diff --git a/rejecting_run b/rejecting_run @@ -0,0 +1,9 @@ +# Rejecting run + +A [run] which finishes at a [nonfinal_state] + +See also: [accepting_run] + +Up: [run] + +Aliases: rejecting runs diff --git a/run b/run @@ -0,0 +1,11 @@ +# Run + +A [sequence] of [states] that starts by an [initial_state] and follows [configurations] on an input [word] + +- [accepting_run] +- [rejecting_run] +- [partial_run] + +Up: [automata_concepts] + +Aliases: runs diff --git a/second_order_logic b/second_order_logic @@ -0,0 +1,14 @@ +# SO + +- [monadic_second_order_logic] +- [descriptive_complexity]: correspondence with [polynomial_hierarchy] + - [existential_second_order_logic] corresponds to [nptime], etc., + [quantifier_prefix] +- [second_order_transitive_closure] SO(TC) [ferrarotti2018expressivity] + - corresponds to [pspace] + - can express [hamiltonian_cycle] + - which is known not to be expressible in [monadic_second_order_logic] + +See also: [first_order_logic] + +Aliases: SO diff --git a/semiring_idempotent b/semiring_idempotent @@ -1,6 +1,6 @@ # Idempotent semiring -A [semiring] satisfying the equation a+a = a for every a ("additively idempotent") +A [semiring] satisfying the equation a+a = a for every a, i.e., [additively_idempotent] Not the case of all [semirings], e.g., not the [natural_numbers] diff --git a/semiring_multiplicative_idempotent b/semiring_multiplicative_idempotent @@ -1,6 +1,6 @@ # Semiring multiplicative idempotent -[Semiring] where s s = s for all s +[Semiring] where s s = s for all s, i.e., [multiplicatively_idempotent] Generalization: [semiring_n_idempotent] diff --git a/theorem b/theorem @@ -6,6 +6,7 @@ A [result] in [mathematics], recognized as challenging to prove - [Brook's_theorem] - [Buchi's_theorem] - [Chen's_theorem] +- [Codd's_theorem] - [Context_free_grammar_pushdown_automaton_equivalence] - [Courcelle_theorem] - [Eggan's_theorem] diff --git a/tropical_semiring b/tropical_semiring @@ -6,8 +6,10 @@ Intuition: you want the derivation with least cost ([min]), and joint use of val Useful for [shortest_path] in [graphs] +It is an [absorptive_semiring] + Up: [semiring_list] -See also: [mpp_minimum], [tropical] +See also: [mpp_minimum], [tropical], [max_plus_semiring] Aliases: semiring tropical diff --git a/turing_machine b/turing_machine @@ -14,6 +14,7 @@ ## Variants - [turing_machine_symmetric] +- [turing_machine_weighted] ## Resources @@ -22,3 +23,5 @@ Up: [theoretical_computer_science] See also: [ram_model], [church_turing_thesis], [alan_turing], [pushdown_automaton], [turing_complete], [decidability], [recursively_enumerable], [kolmogorov_complexity] + +Aliases: Turing machines diff --git a/turing_machine_deterministic b/turing_machine_deterministic @@ -0,0 +1,11 @@ +# Turing machine deterministic + +A [turing_machine] whose [transition_relation] is a [transition_function], so that it has at most one [run] on every input + +- [turing_machine_deterministic_ptime] + +Up: [turing_machine] + +Aliases: deterministic Turing machine, deterministic Turing machines + +See also: [turing_machine_nondeterministic] diff --git a/turing_machine_nondeterministic b/turing_machine_nondeterministic @@ -1,7 +1,11 @@ # Turing machine nondeterministic +A [Turing_machine] which may have several applicable [transitions], so that it can have multiple [runs] on an input + - [nptime]: [nondeterministic_ptime_turing_machine] Up: [turing_machine] Aliases: nondeterministic Turing machine + +See also: [turing_machine_deterministic] diff --git a/turing_machine_weighted b/turing_machine_weighted @@ -0,0 +1,14 @@ +# Turing machine weighted + +[turing_machine_weighted_definition] + +They are to [Turing_machines] what [weighted_automata] are to [automata] + +Can define [complexity_classes] that are [formal_power_series]: [weighted_language_series_correspondence] +- see also [weighted_complexity_classes] in [badia2024logical] + +Were originally called "algebraic turing machines" in [damm2002complexity], connected to [weighted_automata] in [kostolanyi2023weighted] + +Up: [turing_machine], [weighted] + +Aliases: Weighted Turing machine, weighted Turing machines diff --git a/viterbi_semiring b/viterbi_semiring @@ -4,6 +4,8 @@ The [semiring] defined as ([0, 1], [max], [multiplication], 0, 1) Intuitively: you want the derivation with highest confidence ([max]), and when you use several values simultaneously then confidence decreases via [multiplication] +It is an [absorptive_semiring] + Up: [semiring_list] See also: [tropical_semiring]