pinecone/core-2020-05-10-deduplication huggingface dataset:
Differentiation in morphology and flowering phenology between two Campanula thyrsoides L. subspecies

Subspecies are usually characterized by sets of morphological discontinuities. By means of common garden experiments, we investigated genetic differentiation in morphological and phenological traits in two geographically disjunct subspecies of Campanula thyrsoides L., i.e. subsp. thyrsoides (= C.* thyrsoides) occurring in the European Alps and Jura Mountains, and subsp. carniolica (= C.* carniolica) occurring in the Southeastern Alps and the Dinaric Arc. Nine out of 16 investigated traits were significantly different between C.* thyrsoides and C.* carniolica. For C.* carniolica inflorescence length was 1.4×, and above-ground biomass 2.7× higher, while flower density was significantly lower. Campanula* carniolica also showed delayed flowering and flower development from bottom to top compared to C.* thyrsoides which flowered from top to bottom. The inflorescence growth was indeterminate and flowering took several weeks in C.* carniolica, whereas C.* thyrsoides showed determinate flowering, rapidly opening all flowers within a few days. This differentiation in flowering phenology is likely to be adaptive. The submediterranean climate favours indeterminate flowering in C.* carniolica, allowing ongoing growth of the inflorescence throughout the long summer until environmental conditions worsen, whereas determinate and early flowering in C.* thyrsoides is favourable in the short growing season in the high Alps where seed production must be secured before temperature drops. Glacial survival in refugia with different climates (alpine vs. submediterranean) may have caused this regional differentiation
Profiteers of environmental change in the Swiss Alps: increase of thermophilous and generalist plants in wetland ecosystems within the last 10 years

It has been predicted that Northern Europe will experience a rise in temperature of 2.3–5.3°C from now until 2100. This increase in temperature may lead to vegetation change along altitudinal gradients. To test this prediction, we recorded plant-species composition in 1995 and 2005/06 in Swiss pre-alpine fen meadows (800–1400 m a.s.l.). Despite no obvious	changes in the management of these fens, overall, plant-species richness (cumulative number of plant species at five plots per site) significantly increased over this period. This was mainly due to an increase in the number of thermophilous, rich-soil indicator and shade indicator species which corresponded to increased community productivity and shading within the vegetation layer. In contrast, fen specialists significantly declined in species numbers. The strongest shift in vegetation composition occurred at the lowest sites, which overall had a higher colonization rate by new species than did sites at higher altitudes. Vegetation change along the altitudinal gradient was also affected by different types of land management: early- flowering species and species with low habitat-specificity had high colonization rates in grazed fens, especially at low altitudes
Arabis alpina and Arabidopsis thaliana have different stomatal development strategies in response to high altitude pressure conditions

The altitudinal gradient involves changes of the partial pressures of atmospheric gases such as CO2. This omnipresent phenomenon likely represents an evolutionary selective agent. We asked whether high altitude plant species had evolved specific response strategies to cope with high altitude pressure conditions. Plants of the high altitude species Arabis alpina and the low altitude species Arabidopsis thaliana were cultivated in growth chambers with high altitude pressure conditions (corresponding to 3000 m a.s.l.) and low altitude conditions (560 m). In both species, high altitude conditions resulted in the narrowing of stomatal aperture as well as a decrease in leaf area and weight. A. alpina produced significantly more stomata under high altitude conditions compared to low altitude conditions, while A. thaliana did not. Under low altitude conditions, however, stomatal density of A. alpina was smaller compared to A. thaliana. The increase in stomatal density of A. alpina was strongly related to the decrease in the partial pressure of CO2 under high altitude conditions. Thus, the adaptation of the high altitude plant A. alpina to high altitude pressure conditions does not consist in a genetically fixed elevated stomatal density but in a different response strategy of stomatal development to environmental factors compared to the lowland plant A. thaliana. A. alpina developed stomata largely uncoupled from other environmental factors than CO2. The increased stomatal density of A. alpina may ensure an optimal CO2 supply during the periods of favourable weather conditions for photosynthesis that are relatively rare and short in the alpine life zone
Patterns of herbivore damage, developmental stability, morphological and biochemical traits in female and male Mercurialis perennis in contrasting light habitats

Light environments can influence variation in plant morphology, development and susceptibility to herbivores. Our research interest was to investigate the patterns of herbivore damage and developmental stability in dioecious understory forb Mercurialis perennis in contrasting light habitats, located at 1700 m a.s.l. on Mt. Kopaonik. Male and female plants from two light habitats, open (a sun-exposed field) and shaded (a spruce forest) were examined with respect to: herbivore damage (percentage of leaf area loss), fluctuating asymetry (FA) as a measurement of developmental stability, plant morphological and, specifically, leaf size traits, as well as biochemical traits relating to nutritional quality and defence, taking into account the possible presence of intersexual differences. Our results show that herbivore damage was significantly higher in open habitat, as well as one out of four univariate FA indices and the multivariate index. Morphological and biochemical traits, apart from defensive compounds, had higher values in the shade, pointing to sun-exposed habitat being more stressful for this species. Intersexual differences were observed for foliar damage, defensive compounds (phenolics and tannins), all leaf size traits, total leaf area, and protein content. Contrasting light habitats affected most of the analysed traits. Both foliar damage and FA were higher in a more stressful habitat; within habitats, no positive correlations were found. Herbivore damage was significantly male biased in open habitat. The analysis of intersexual differences in developmental stability measured by leaf asymmetry levels provided no evidence that female plants were more sensitive to environmental stress.This is a post-peer-review, pre-copyedit version of an article published in Alpine Botany. The final authenticated version is available online at: [http://dx.doi.org/10.1007/s00035-018-0203-8
On Interactive Proofs with a Laconic Prover

We continue the investigation of interactive proofs with bounded communication, as initiated by Goldreich & Håstad (1998). Let <i>L</i> be a language that has an interactive proof in which the prover sends few (say <i>b</i>) bits to the verifier. We prove that the complement $\bar L$ has a <i>constant-round</i> interactive proof of complexity that depends only exponentially on <i>b</i>. This provides the first evidence that for <b>NP</b>-complete languages, we cannot expect interactive provers to be much more "laconic" than the standard <b>NP</b> proof. When the proof system is further restricted (e.g., when b = 1, or when we have perfect completeness), we get significantly better upper bounds on the complexity of $\bar L$.Engineering and Applied Science
Polynomial-time computing over quadratic maps I: sampling in real
  algebraic sets

Given a quadratic map Q : K^n -> K^k defined over a computable subring D of a
real closed field K, and a polynomial p(Y_1,...,Y_k) of degree d, we consider
the zero set Z=Z(p(Q(X)),K^n) of the polynomial p(Q(X_1,...,X_n)). We present a
procedure that computes, in (dn)^O(k) arithmetic operations in D, a set S of
(real univariate representations of) sampling points in K^n that intersects
nontrivially each connected component of Z. As soon as k=o(n), this is faster
than the standard methods that all have exponential dependence on n in the
complexity. In particular, our procedure is polynomial-time for constant k. In
contrast, the best previously known procedure (due to A.Barvinok) is only
capable of deciding in n^O(k^2) operations the nonemptiness (rather than
constructing sampling points) of the set Z in the case of p(Y)=sum_i Y_i^2 and
homogeneous Q.
  A by-product of our procedure is a bound (dn)^O(k) on the number of connected
components of Z.
  The procedure consists of exact symbolic computations in D and outputs
vectors of algebraic numbers. It involves extending K by infinitesimals and
subsequent limit computation by a novel procedure that utilizes knowledge of an
explicit isomorphism between real algebraic sets.Comment: 34 pages, LaTeX (Computational Complexity (cc.cls) class used);
  updated version, to appear in Comp. Complexit
Pseudorandomness and Average-Case Complexity via Uniform Reductions

Impagliazzo and Wigderson (36th FOCS, 1998) gave the first construction of pseudorandom generators from a <i>uniform</i> complexity assumption on EXP (namely EXP [not equal to] BPP). Unlike results in the nonuniform setting, their result does not provide a continuous trade-off between worst-case hardness and pseudorandomness, nor does it explicitly establish an average-case hardness result.

In this paper:

   1. We obtain an optimal worst-case to average-case connection for EXP: if  EXP is not a subset of BPTIME(t(n)), EXP has problems that cannot be solved on a fraction 1/2 +1/t'(n) of the inputs by BPTIME(t'(n)) algorithms, for t'=t^{\Omega(1)}.
       
   2. We exhibit a PSPACE-complete self-correctible and downward self-reducible problem. This slightly simplifies and strengthens the proof of Impaglaizzo and Wigderson, which used a a #P-complete problem with these properties.
       
   3. We argue that the results of Impagliazzo and Wigderson, and the ones in this paper, cannot be proved via "black-box" uniform reductions.Engineering and Applied Science
Probabilistic communication complexity over the reals

International audienceDeterministic and probabilistic communication protocols are introduced in which parties can exchange the values of polynomials (rather than bits in the usual setting). It is established a sharp lower bound $2n$ on the communication complexity of recognizing the $2n$-dimensional orthant, on the other hand the probabilistic communication complexity of its recognizing does not exceed 4. A polyhedron and a union of hyperplanes are constructed in $\RR^{2n}$ for which a lower bound $n/2$ on the probabilistic communication complexity of recognizing each is proved. As a consequence this bound holds also for the EMPTINESS and the KNAPSACK problems
Lipschitz Continuous Ordinary Differential Equations are
  Polynomial-Space Complete

In answer to Ko's question raised in 1983, we show that an initial value
problem given by a polynomial-time computable, Lipschitz continuous function
can have a polynomial-space complete solution. The key insight is simple: the
Lipschitz condition means that the feedback in the differential equation is
weak. We define a class of polynomial-space computation tableaux with equally
weak feedback, and show that they are still polynomial-space complete. The same
technique also settles Ko's two later questions on Volterra integral equations.Comment: 22 pages, 9 figures; preliminary version presented at CCC 200
Inapproximability of the Tutte polynomial of a planar graph

The Tutte polynomial of a graph G is a two-variable polynomial T(G;x,y) that
encodes many interesting properties of the graph. We study the complexity of
the following problem, for rationals x and y: given as input a planar graph G,
determine T(G;x,y). Vertigan completely mapped the complexity of exactly
computing the Tutte polynomial of a planar graph. He showed that the problem
can be solved in polynomial time if (x,y) is on the hyperbola H_q given by
(x-1)(y-1)=q for q=1 or q=2 or if (x,y) is one of the two special points
(x,y)=(-1,-1) or (x,y)=(1,1). Otherwise, the problem is #P-hard. In this paper,
we consider the problem of approximating T(G;x,y), in the usual sense of "fully
polynomial randomised approximation scheme" or FPRAS. Roughly speaking, an
FPRAS is required to produce, in polynomial time and with high probability, an
answer that has small relative error. Assuming that NP is different from RP, we
show that there is no FPRAS for the Tutte polynomial in a large portion of the
(x,y) plane. In particular, there is no FPRAS if x>1, y<-1 or if y>1, x<-1 or
if x<0, y<0 and q>5. Also, there is no FPRAS if x<1, y<1 and q=3. For q>5, our
result is intriguing because it shows that there is no FPRAS at
(x,y)=(1-q/(1+epsilon),-epsilon) for any positive epsilon but it leaves open
the limit point epsilon=0, which corresponds to approximately counting
q-colourings of a planar graph.Comment: In this revision, significant changes have been made to the structure
  of the paper to clarify the presentation. Extra detail has been provided at
  certain points in the proofs, and on at least one occasion the exposition has
  been made more systematic. Some typos have been corrected. The results are
  unchanged. 28 pages and 5 figure
Rank complexity gap for Lovász-Schrijver and Sherali-Adams proof systems.

We prove a dichotomy theorem for the rank of propositional contradictions, uniformly generated from first-order sentences, in both the Lovász-Schrijver (LS) and Sherali-Adams (SA) refutation systems. More precisely, we first show that the propositional translations of first-order formulae that are universally false, that is, fail in all finite and infinite models, have LS proofs whose rank is constant, independent of the size of the (finite) universe. In contrast to that, we prove that the propositional formulae that fail in all finite models, but hold in some infinite structure, require proofs whose SA rank grows polynomially with the size of the universe.\ud
\ud
Until now, this kind of so-called complexity gap theorem has been known for tree-like Resolution and, in somehow restricted forms, for the Resolution and Nullstellensatz systems. As far as we are aware, this is the first time the Sherali-Adams lift-and-project method has been considered as a propositional refutation system (since the conference version of this paper, SA has been considered as a refutation system in several further papers). An interesting feature of the SA system is that it simulates LS, the Lovász-Schrijver refutation system without semi-definite cuts, in a rank-preserving fashion
Modular Composition Modulo Triangular Sets and Applications

International audienceWe generalize Kedlaya and Umans' modular composition algorithm to the multivariate case. As a main application, we give fast algorithms for many operations involving triangular sets (over a finite field), such as modular multiplication, inversion, or change of order. For the first time, we are able to exhibit running times for these operations that are almost linear, without any overhead exponential in the number of variables. As a further application, we show that, from the complexity viewpoint, Charlap, Coley, and Robbins' approach to elliptic curve point counting can be competitive with the better known approach due to Elkies
Parallel approximation of min-max problems

This paper presents an efficient parallel approximation scheme for a new
class of min-max problems. The algorithm is derived from the matrix
multiplicative weights update method and can be used to find near-optimal
strategies for competitive two-party classical or quantum interactions in which
a referee exchanges any number of messages with one party followed by any
number of additional messages with the other. It considerably extends the class
of interactions which admit parallel solutions, demonstrating for the first
time the existence of a parallel algorithm for an interaction in which one
party reacts adaptively to the other.
  As a consequence, we prove that several competing-provers complexity classes
collapse to PSPACE such as QRG(2), SQG and two new classes called DIP and DQIP.
A special case of our result is a parallel approximation scheme for a specific
class of semidefinite programs whose feasible region consists of lists of
semidefinite matrices that satisfy a transcript-like consistency condition.
Applied to this special case, our algorithm yields a direct polynomial-space
simulation of multi-message quantum interactive proofs resulting in a
first-principles proof of QIP=PSPACE.Comment: 28 pages. Final version, compiled in letterpaper with reasonable
  margin
On the Power of Non-adaptive Learning Graphs

We introduce a notion of the quantum query complexity of a certificate structure. This is a formalization of a well-known observation that many quantum query algorithms only require the knowledge of the position of possible certificates in the input string, not the precise values therein.

Next, we derive a dual formulation of the complexity of a non-adaptive learning graph and use it to show that non-adaptive learning graphs are tight for all certificate structures. By this, we mean that there exists a function possessing the certificate structure such that a learning graph gives an optimal quantum query algorithm for it.

For a special case of certificate structures generated by certificates of bounded size, we construct a relatively general class of functions having this property. The construction is based on orthogonal arrays and generalizes the quantum query lower bound for the k-sum problem derived recently by Belovs and Špalek (Proceeding of 4th ACM ITCS, 323–328, 2013).

Finally, we use these results to show that the learning graph for the triangle problem by Lee et al. (Proceeding of 24th ACM-SIAM SODA, 1486–1502, 2013) is almost optimal in the above settings. This also gives a quantum query lower bound for the triangle sum problem.National Science Foundation (U.S.) (Scott Aaronson’s Alan T. Waterman Award
Rank-one quantum games

In this work, we study rank-one quantum games. In particular, we focus on the study of the computability of the entangled value ω*. We show that the value ω* can be efficiently approximated up to a multiplicative factor of 4. We also study the behavior of ω* under the parallel repetition of rank-one quantum games, showing that it does not verify a perfect parallel repetition theorem. To obtain these results, we first connect rank-one games with the mathematical theory of operator spaces. We also reprove with these new tools essentially known results about the entangled value of rank-one games with one-way communication ω qow . In particular, we show that ω qow can be computed efficiently and it satisfies a perfect parallel repetition theorem
Quantum Algorithms for Learning Symmetric Juntas via the Adversary Bound

In this paper, we study the following variant of the junta learning problem. We are given oracle access to a Boolean function f on n variables that only depends on k variables, and, when restricted to them, equals some predefined function h. The task is to identify the variables the function depends on.When h is the XOR or the OR function, this gives a restricted variant of the Bernstein–Vazirani or the combinatorial group testing problem, respectively.

We analyze the general case using the adversary bound and give an alternative formulation for the quantum query complexity of this problem. We construct optimal quantum query algorithms for the cases when h is the OR function (complexity is  Θ(√k) ) or the exact-half function (complexity is O(k[supercript 1/4])). The first algorithm resolves an open problem from Ambainis & Montanaro (Quantum Inf Comput 14(5&6): 439–453, 2014). For the case when h is the majority function, we prove an upper bound of O(k[supercript 1/4]). All these algorithms can be made exact. We obtain a quartic improvement when compared to the randomized complexity (if h is the exact-half or the majority function), and a quadratic one when compared to the non-adaptive quantum complexity (for all functions considered in the paper).National Science Foundation (U.S.) (Scott Aaronson’s Alan T. Waterman Award
The Minimum Oracle Circuit Size Problem

We consider variants of the minimum circuit size problem MCSP, where the goal is to minimize the size of oracle circuits computing a given function. When the oracle is QBF, the resulting problem MSCP[superscript QBF] is known to be complete for PSPACE under ZPP reductions. We show that it is not complete under logspace reductions, and indeed it is not even hard for TC[superscript 0] under uniform AC[superscript 0] reductions. We obtain a variety of consequences that follow if oracle versions of MCSP are hard for various complexity classes under different types of reductions. We also prove analogous results for the problem of determining the resource-bounded Kolmogorov complexity of strings, for certain types of Kolmogorov complexity measures.National Science Foundation (U.S.) (grants CCF-1064785, CCF-1423544, and CCF-1555409)Natural Sciences and Engineering Research Council of Canada (Discovery Grant
The Value of Help Bits in Randomized and Average-Case Complexity

"Help bits" are some limited trusted information about an instance or
instances of a computational problem that may reduce the computational
complexity of solving that instance or instances. In this paper, we study the
value of help bits in the settings of randomized and average-case complexity.
  Amir, Beigel, and Gasarch (1990) show that for constant $k$, if $k$ instances
of a decision problem can be efficiently solved using less than $k$ bits of
help, then the problem is in P/poly. We extend this result to the setting of
randomized computation: We show that the decision problem is in P/poly if using
$\ell$ help bits, $k$ instances of the problem can be efficiently solved with
probability greater than $2^{\ell-k}$. The same result holds if using less than
$k(1 - h(\alpha))$ help bits (where $h(\cdot)$ is the binary entropy function),
we can efficiently solve $(1-\alpha)$ fraction of the instances correctly with
non-vanishing probability. We also extend these two results to non-constant but
logarithmic $k$. In this case however, instead of showing that the problem is
in P/poly we show that it satisfies "$k$-membership comparability," a notion
known to be related to solving $k$ instances using less than $k$ bits of help.
  Next we consider the setting of average-case complexity: Assume that we can
solve $k$ instances of a decision problem using some help bits whose entropy is
less than $k$ when the $k$ instances are drawn independently from a particular
distribution. Then we can efficiently solve an instance drawn from that
distribution with probability better than $1/2$.
  Finally, we show that in the case where $k$ is super-logarithmic, assuming
$k$-membership comparability of a decision problem, one cannot prove that the
problem is in P/poly by a "black-box proof.