arXiv subjects

William George

Publications and source records attributed to William George.

4 recordsLinked to original sources

arXiv2023

Searches for rare top quark production and decay processes with the ATLAS experiment

The large integrated luminosity collected by the ATLAS detector at the LHC provides the opportunity to probe the presence of new physics that could enhance the rate of very rare processes in the Standard Model (SM). The LHC can therefore gain considerable sensitivity for flavour changing neutral current (FCNC) and charged lepton flavour violating (CLFV) interactions of the top quark. In the SM, FCNCs are highly suppressed while CLFV interactions are forbidden so any measurable branching ratio for such a process is an indication of new physics. The production of four top quarks is a rare SM process which also provides sensitivity to new physics processes. In this contribution, the latest results of searches for these processes are presented.

hep-ex↗

arXiv2017

Transforming face-to-face identity proofing into anonymous digital identity using the Bitcoin blockchain

The most fundamental purpose of blockchain technology is to enable persistent, consistent, distributed storage of information. Increasingly common are authentication systems that leverage this property to allow users to carry their personal data on a device while a hash of this data is signed by a trusted authority and then put on a blockchain to be compared against. For instance, in 2015, MIT introduced a schema for the publication of their academic certificates based on this principle. In this work, we propose a way for users to obtain assured identities based on face-to-face proofing that can then be validated against a record on a blockchain. Moreover, in order to provide anonymity, instead of storing a hash, we make use of a scheme of Brands to store a commitment against which one can perform zero-knowledge proofs of identity. We also enforce the confidentiality of the underlying data by letting users control a secret of their own. We show how our schema can be implemented on Bitcoin's blockchain and how to save bandwidth by grouping commitments using Merkle trees to minimize the number of Bitcoin transactions that need to be sent. Finally, we describe a system in which users can gain access to services thanks to the identity records of our proposal.

cs.CR↗

arXiv2017

A User-Centric System for Verified Identities on the Bitcoin Blockchain

We present an identity management scheme built into the Bitcoin blockchain, allowing for identities that are as indelible as the blockchain itself. Moreover, we take advantage of Bitcoin's decentralized nature to facilitate a shared control between users and identity providers, allowing users to directly manage their own identities, fluidly coordinating identities from different providers, even as identity providers can revoke identities and impose controls.

cs.CR↗

arXiv2009

The spiral index of knots

Two new invariants that are closely related to Milnor's curvature-torsion invariant are introduced. The first, the spiral index of a knot, captures the minimum number of maxima among all knot projections that are free of inflection points. This invariant is closely related to both the bridge and braid index of the knot. The second, the projective superbridge index, provides a method of counting the greatest number of maxima that occur in a given knot projection. In addition to investigating how these invariants are related to the classical invariants, we utilize them to determine all knots with curvature-torsion invariant equal to 6 pi.

math.GT↗