Publications related to Principal bundle

FIBERED TORIC VARIETIES

A toric variety is called fibered if it can be represented as a total space of fibre bundle over toric base and with toric fiber. Fibered toric varieties form a special case of toric variety bundles. In this note we first give an introduction to the class ...

Independent Univ Moscow-Ium2023

Axonal and Dendritic Morphology of Excitatory Neurons in Layer 2/3 Mouse Barrel Cortex Imaged Through Whole-Brain Two-Photon Tomography and Registered to a Digital Brain Atlas

Carl Petersen, Sylvain Crochet, Georgios Foustoukos, Yanqi Liu

Communication between cortical areas contributes importantly to sensory perception and cognition. On the millisecond time scale, information is signaled from one brain area to another by action potentials propagating across long-range axonal arborizations. ...

FRONTIERS MEDIA SA2022

Ordinary varieties with trivial canonical bundle are not uniruled

Zsolt Patakfalvi, Maciej Emilian Zdanowicz

We prove that smooth, projective, K-trivial, weakly ordinary varieties over a perfect field of characteristic p>0 are not geometrically uniruled. We also show a singular version of our theorem, which is sharp in multiple aspects. Our work, together with La ...

2021

Bundle-Specific Axon Diameter Index as a New Contrast to Differentiate White Matter Tracts

Jean-Philippe Thiran, David Paul Roger Romascano, Gabriel Girard, Alessandro Daducci, Cristina Granziera, Muhamed Barakovic, Maxime Descoteaux, Giorgio Innocenti

In the central nervous system of primates, several pathways are characterized by different spectra of axon diameters. In vivo methods, based on diffusion-weighted magnetic resonance imaging, can provide axon diameter index estimates non-invasively. However ...

2021

Three-dimensional fabrication of sub-micron optical waveguides in PDMS and other polymer materials

Giulia Panusa

Optical waveguides are one of the most important photonic components. They are indispensable tools in many of todayâ s technologies because of their capacity of guiding light. In particular, compact, low loss, flexible polymer optical waveguides are cruci ...

EPFL2021

Quasi-categories vs. Segal spaces: Cartesian edition

Nima Rasekh

We prove that four different ways of defining Cartesian fibrations and the Cartesian model structure are all Quillen equivalent: 1.On marked simplicial sets (due to Lurie [31]), 2.On bisimplicial spaces (due to deBrito [12]), 3.On bisimplicial sets, 4.On m ...

2021

Resolving bundle-specific intra-axonal T2 values within a voxel using diffusion-relaxation tract-based estimation

Jean-Philippe Thiran, Erick Jorge Canales Rodriguez, Alessandro Daducci, Muhamed Barakovic, Cristina Granziera

At the typical spatial resolution of MRI in the human brain, approximately 60–90% of voxels contain multiple fiber populations. Quantifying microstructural properties of distinct fiber populations within a voxel is therefore challenging but necessary. Whil ...

2020

Arithmetically rigid schemes via deformation theory of equivariant vector bundles

Maciej Emilian Zdanowicz

We analyze the deformation theory of equivariant vector bundles. In particular, we provide an effective criterion for verifying whether all infinitesimal deformations preserve the equivariant structure. As an application, using rigidity of the Frobenius ho ...

SPRINGER HEIDELBERG2021

Characteristic classes as complete obstructions

Martina Rovelli

In the first part of this paper, we propose a uniform interpretation of characteristic classes as obstructions to the reduction of the structure group and to the existence of an equivariant extension of a certain homomorphism defined a priori only on a sin ...

SPRINGER HEIDELBERG2019

Configuration Spaces Of Products

Kathryn Hess Bellwald

We show that the configuration spaces of a product of parallelizable manifolds may be recovered from those of the factors as the Boardman-Vogt tensor product of right modules over the operads of little cubes of the appropriate dimension. We also discuss an ...

2019

Modular functors, cohomological field theories, and topological recursion

Nicolas Gerson Orantin

Given a topological modular functor V in the sense of Walker, we construct vector bundles Z (lambda) over bar, over (M) over bar (g,n) whose Chern characters define semi-simple cohomological field theories. This construction depends on a determinati ...

AMER MATHEMATICAL SOC2018

A Looping-Delooping Adjunction For Topological Spaces

Martina Rovelli

Every principal G-bundle over X is classified up to equivalence by a homotopy class X -> BG, where BG is the classifying space of G. On the other hand, for every nice topological space X Milnor constructed a strict model of its loop space (Omega) over tild ...

Int Press Boston, Inc2017

Towards new invariants for principal bundles

Martina Rovelli

We investigate the theory of principal bundles from a homotopical point of view. In the first part of the thesis, we prove a classification of principal bundles over a fixed base space, dual to the well-known classification of bundles with a fixed structur ...

EPFL2017

Distributed photothermal spectroscopy in microstructured optical fibers: towards high-resolution mapping of gas presence over long distances

Luc Thévenaz, Kenny Hey Tow

Chemical sensing using optical fibers is often challenging, as it is generally difficult to achieve strong interaction between the guided light and the analyte at the wavelength of interest for performing the detection. Despite this difficulty, many scheme ...

Optical Society of America2017

Fracture of thin-ply composites : effects of ply thickness

Guillaume Frossard

The demand for carbon/epoxy laminated composites is continuously increasing due to their high specific modulus and strength. Among them, laminates made of particularly thin layers (from t=0.015 to 0.150 mm) and called thin-ply composites are gaining in int ...

EPFL2017

Unified prefetching into instruction cache and branch target buffer

Babak Falsafi, Boris Robert Grot, Ilknur Cansu Kaynak

A system and method of coupling a Branch Target Buffer (BTB) content of a BTB with an instruction cache content of an instruction cache. The method includes: tagging a plurality of target buffer entries that belong to branches within a same instruction blo ...

2017

Control of pulsed light propagation through multimode optical fibers

Edgar Emilio Morales Delgado

Visualization of organs and cells in the interior of living beings is a challenging task due to the light absorption and multiple light scattering occurring in biological tissue that prevents the di-rect transmission of images. A standard visualization app ...

EPFL2017

Two-photon excitation endoscopy through a multimode optical fiber

Demetri Psaltis, Christophe Moser, Edgar Emilio Morales Delgado

The vast number of propagating solutions to the wave equation in multimode optical fibers represents a larger information capacity than provided by fiber bundles of the same diameter. Therefore, in the field of imaging, multimode fibers potentially allow t ...

Spie-Int Soc Optical Engineering2016

Fiber bundle model under fluid pressure

Internal fluid pressure often plays an important role in the rupture of brittle materials. This is a major concern for many engineering applications and for natural hazards. More specifically, the mechanisms through which fluid pressure, applied at a micro ...

Amer Physical Soc2016

Dendrimer-Stabilized Titanate Nanowire Dispersions as Potential Nanocarriers

László Forró, Endre Horvath, Marko Pavlovic

The effect of poly(amido amine) (PAMAM) dendrimers of generations G2, G6, and G10 on the dispersion stability of titanate nanowires (TiONWs) as potential nanocarriers was clarified in order to develop biocompatible delivery systems. The PAMAMs adsorbed str ...

Amer Chemical Soc2015