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Some remarks on SLE bubbles and Schramm's two-point observable [article]

Dmitry Beliaev, Fredrik Johansson Viklund
2011 arXiv   pre-print
In this paper we give a rigorous proof of their formula.  ...  Simmons and Cardy recently predicted a formula for the probability that the chordal SLE(8/3) path passes to the left of two points in the upper half-plane.  ...  Numerical evaluation supports to some extent the above hypothesis. In the last section we consider infinite SLE bubbles.  ... 
arXiv:1012.5206v2 fatcat:a3baojvcanc4bdur6yulhlahuy

SOME OBSERVATIONS ON TRUTH HIERARCHIES

P. D. WELCH
2014 The Review of Symbolic Logic  
(To take some terminology from [2], the internal sets  ...  Paths defined 'externally' to the model in any way, presumably have no length restrictions, and would correspond to some kind of 'super-determinateness'.  ...  We independently established that the universal Infinite Time Turing Machine of [10] also enters a final loop with the same (ζ, Σ) the first such pair (see [23] for an account of this).  ... 
doi:10.1017/s1755020313000361 fatcat:cokosamcljhkjlg5ofd4yv4eue

Some Observable Effects of Modified Gravity in Cosmology and Astrophysics [article]

Lorenzo Reverberi
2014 arXiv   pre-print
and its implications for the early and contemporary universe; in Chapter 3 I investigate the formation of curvature singularities in contracting astronomical systems; in Chapter 4, I discuss some mechanisms  ...  The following Chapters essentially contain the published papers with some modifications and additions: in Chapter 2 I study the radiation-dominated epoch in R^2 gravity, gravitational particle production  ...  I showed that such infinite-R, finite-singularities can arise in a number of physically reasonable systems, and derived the time scales for this to happen.  ... 
arXiv:1406.6943v1 fatcat:bzbgdgeh4bbpfdyj6ouiezykcy

Some observations about isogenies between K3 surfaces [article]

Marie José Bertin, Odile Lecacheux
2020 arXiv   pre-print
For example some of its elliptic fibrations with 3-torsion section induce by 3-isogeny either an elliptic fibration of Y_2, the unique K3 surface of discriminant 8, or an elliptic fibration of other K3  ...  Recalling the elliptic fibrations in the generic case [6] Table 2 , we derive some observations.  ...  Some remarks.  ... 
arXiv:2006.16108v1 fatcat:gehbzfcdvbbo3bbbxbnfftcrl4

Some models of holographic dark energy on the Randall-Sundrum brane and observational data [article]

Artyom V. Astashenok, Alexander S. Tepliakov
2019 arXiv   pre-print
Analysis of observational data allows to define upper limit on value of δ=ρ_0/2λ (ρ_0 is current energy density in the Universe and λ is brane tension).  ...  The some models of holographic dark energy for Randall-Sandrum brane are considered.  ...  One also note that for 1.5 ≤ γ < 2 life of universe ends in so called "big freeze" singularity (Hubble parameter diverges for finite time but scale factor a = a f = ∞).  ... 
arXiv:1911.01422v1 fatcat:l7lbess3kvek3ikhua76q6oi2q

Linear Time Logic Control of Discrete-Time Linear Systems

Paulo Tabuada, George J. Pappas
2006 IEEE Transactions on Automatic Control  
We show that existence of controllers for discrete-time controllable linear systems and LTL specifications can be decided and that such controllers can be effectively computed.  ...  The closed-loop system is of hybrid nature, combining the original continuous dynamics with the automatically synthesized switching logic required to enforce the specification.  ...  As discussed in [KG95] , a finite supervisor that is implementable 6 necessarily has finite memory and therefore can only restrict the infinite behavior of A P ∆ based on finite length observations.  ... 
doi:10.1109/tac.2006.886494 fatcat:3mlrq7z3hja5na4v6s4pdncazm

Discrete-time feedback stabilization

Wojciech Mitkowski, Waldemar Bauer, Marta Zagórowska
2017 Archives of Control Sciences  
The proposed method was then implemented in order to find the control function for thin rod heating process. The optimal sampling time was found depending on discrete output measurements.  ...  This paper presents an algorithm for designing dynamic compensator for infinitedimensional systems with bounded input and bounded output operators using finite dimensional approximation.  ...  Finite dimensional stabilization problem: for a given infinite system S find a stabilizing controller (finite dimensional) such that the closed-loop system is exponentially stable with predefined damping  ... 
doi:10.1515/acsc-2017-0020 fatcat:x6sjj7kadvfr5knbrz5sqkompa

Branching Time? Pruning Time! [chapter]

Markus Latte, Martin Lange
2012 Lecture Notes in Computer Science  
These can be pruned into finite trees using fixpoint strengthening and some simple combinatorial machinery such that the results represent proofs in a Hilbert-style axiom system for this fragment.  ...  We present infinite satisfiability games for this fragment. Winning strategies for one of the players represent infinite tree models for satisfiable formulas.  ...  We then employ combinatorial arguments and logical principles by which winning strategies in these games, which are infinite trees, can be made finite and loop-free.  ... 
doi:10.1007/978-3-642-31365-3_31 fatcat:r2yqqg4ie5bgbjyg2igf753e4y

Infinite-Time TuringMachines [chapter]

2008 Hypercomputation  
Infinite time Turing machines extend the operation of ordinary Turing machines into transfinite ordinal time.  ...  This algorithm is infinite time computable by some program q.  ...  The essence of an infinitely fast computer, of course, is that it is able to complete infinitely many steps of computation in a finite amount of time.  ... 
doi:10.1007/978-0-387-49970-3_4 fatcat:b3xt6bt4vzcxnfzrgir6rtxcue

Intersection of Regular Signal-Event (Timed) Languages [chapter]

Béatrice Bérard, Paul Gastin, Antoine Petit
2006 Lecture Notes in Computer Science  
While several constructions have been proposed in particular cases, it is the first time, up to our knowledge, that a construction working on finite and infinite signal-event words and taking into account  ...  We write Z * (respectively Z ω ) the set of finite (respectively infinite) sequences of elements in Z, with ε for the empty sequence, and Z ∞ = Z * ∪ Z ω the a, p1, q1, 0 τ, z ≤ 0 a, p2, q1, 0 τ, z ≤ 0  ...  Conclusion We proposed in this paper a construction for the intersection of two signal-event automata in the most general framework, working on finite and infinite signal-event words and taking into account  ... 
doi:10.1007/11867340_5 fatcat:s5tooyj6mzd27peh7rp5h7li7i

Hilbert's Inferno: Time Travel for the Damned

Alasdair M. Richmond
2013 Ratio  
Fourthly, rates of temporal passage are either constant for all observers or at most can only diverge within finite bounds, (e.g. so you can't give some observers an infinite duration in a finite interval  ...  or performer), whereas with bifurcated supertasks, infinitely many sub-tasks occupy finite time for an observer but infinite time for their performers.  ... 
doi:10.1111/rati.12012 fatcat:xu52j477fbgtvmuyungnqxn26i

The Timestamp of Timed Automata [article]

Amnon Rosenmann
2019 arXiv   pre-print
Given a member A of the class of non-deterministic timed automata with silent transitions (eNTA), we effectively compute its timestamp: the set of all pairs (time value, action) of all observable timed  ...  As a consequence, we have a partial method, not bounded by time or number of steps, for the general language non-inclusion problem for eNTA.  ...  at time t in some run of A.  ... 
arXiv:1412.5669v5 fatcat:b7e34t57dvhjbarigfcn5e55q4

Time After Time — Big Bang Cosmology and the Arrows of Time [chapter]

Rüdiger Vaas
2011 The Arrows of Time  
Time, as familiar  ...  Acknowledgements Though time might be an illusion, deadlines are not.  ...  A good illustration (or candidate) is the spin foam approach in loop quantum gravity (see [9, 106, 114] ), but in principle spin networks would also suffice (see [123, 124] ), and some versions of loop  ... 
doi:10.1007/978-3-642-23259-6_2 fatcat:xiky3q6syvdkpbudwd72xqqyyq

Space and Time Complexity for Infinite Time Turing Machines [article]

Merlin Carl
2019 arXiv   pre-print
This considerably expands our earlier observations on the topic in section 7.2.2 of , which appear here as Lemma 6 up to Corollary 9.  ...  We consider notions of space complexity for Infinite Time Turing Machines (ITTMs) that were introduced by B. Löwe and studied further by J. Winter.  ...  If x ∈ X, i.e. if P x n(x) halts in < ω CK,x 2 many steps, then Q x enters an infinite loop; otherwise, Q x halts.  ... 
arXiv:1905.06832v6 fatcat:hbv7clmaknhgtpv6wx3rsolhwe

How to stop time stopping

Howard Bowman, Rodolfo Gómez
2006 Formal Aspects of Computing  
Some time ago, Tripakis proposed a syntactic check on the structure of timed automata: If a certain condition (called strong non-zenoness) is met by all the loops in a given automaton, then zeno-timelocks  ...  Furthermore, our conditions identify the cause of zenotimelocks directly on the model, in the form of unsafe loops.  ...  This represents a situation where the system performs an infinite number of actions in a finite period of time.  ... 
doi:10.1007/s00165-006-0010-7 fatcat:d7cvbbmdabhutofjefc5ratpba
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