Indian Institutes of Science Education and Research

About: Indian Institutes of Science Education and Research is a based out in . It is known for research contribution in the topics: Gravitational wave & LIGO. The organization has 584 authors who have published 731 publications receiving 40599 citations. The organization is also known as: IISERs.

Structural response to the magnetic pre ordering in LiFeSi2O6

Abstract: We investigate the temperature evolution of the structural parameters of potential ferrotoroidic LiFeSi2O6 compound across structural and magnetic phase transitions. The structural transition (TS)is around 220K and the paramagnetic to antiferromagnetic transition (TN) is around 18K. The lattice parameters exhibit unusual temperature dependence and based on its behaviour, the exper- imental results can be divided into 3 this http URL region I (300K to 240K), the cell parameters are mainly governed by mere thermal effect. As the compound enters region II (below 240K to 50K), the lattice parameters show non linear behaviour. In this region, the exchange pathways that lead to the magnetic interactions within and between the Fe-Fe chains do not show significant response.The region III (below 50K) is dominated by the magnetic contribution where we observe setting up of intra and inter-chain magnetic interaction. This behaviour is unlike other low dimensional com- pounds like Ca3Co2O6, Sr3NiRhO6, MnTiO3 etc. thereby suggesting the magnetism in LiFeSi2O6 is of three dimensional nature. The present results will be helpful in understanding the evolution of the spin rings that give rise to net toroidal moment and hence its multiferroic behaviour.

Constant Factor Approximation for the Weighted Partial Degree Bounded Edge Packing Problem

Abstract: In the partial degree bounded edge packing problem (PDBEP), the input is an undirected graph \(G=(V,E)\) with capacity \(c_v\in {\mathbb {N}}\) on each vertex The objective is to find a feasible subgraph \(G'=(V,E')\) maximizing \(|E'|\), where \(G'\) is said to be feasible if for each \(e=\{u,v\}\in E'\), \(\deg _{G'}(u)\le c_u\) or \(\deg _{G'}(v)\le c_v\) In the weighted version of the problem, additionally each edge \(e\in E\) has a weight w(e) and we want to find a feasible subgraph \(G'=(V,E')\) maximizing \(\sum _{e\in E'} w(e)\) The problem is already NP-hard if \(c_v = 1\) for all \(v\in V\) [Zhang, FAW-AAIM 2012]

Punctual gluing of $t$-structures and weight structures

Abstract: We formulate a notion of “punctual gluing” of t-structures and weight structures. As our main application we show that the relative version of Ayoub’s 1-motivic t-structure restricts to compact motives. We also demonstrate the utility of punctual gluing by recovering several constructions in literature. In particular we construct the weight structure on the category of motivic sheaves over any base X and we also construct the relative Artin motive and the relative Picard motive of any variety $$Y{/}X$$.

Device-independent bounds from Cabello's nonlocality argument

Abstract: Hardy-type arguments manifest Bell nonlocality in one of the simplest possible ways. Except for demonstrating nonclassical signature of entangled states in question, they can also serve for device-independent self-testing of states, as shown, e.g., in Phys. Rev. Lett. 109, 180401 (2012). Here we develop and broaden these results to an extended version of Hardy's argument, often referred to as Cabello's nonlocality argument. We show that, as in the simpler case of Hardy's nonlocality argument, the maximum quantum value for Cabello's nonlocality is achieved by a pure two-qubit state and projective measurements that are unique up to local isometries. We also examine the properties of a more realistic case when small errors in the ideal constraints are accepted within the probabilities obtained and prove that also in this case the two-qubit state and measurements are sufficient for obtaining the maximum quantum violation of the classical bound.

Angular changes of Fourier coefficients at primes

Abstract: We study the angle changes of Fourier coefficients of cusp forms and q-exponents of generalized modular functions at primes. More precisely, we prove that both these subsequences, under certain conditions, fall infinitely often outside any given wedge \(\mathcal {W}(\theta _1, \theta _2):=\{re^{i\theta }: r>0, \theta \in [\theta _1,\theta _2]\}\) with \(0\le \theta _2-\theta _1< \pi \).