Published work

Understanding the behaviour of a quantum system coupled to its environment is of fundamental interest in the general field of quantum technologies. It also has important repercussions on foundational problems in physics, such as the process of decoherence and the so-called quantum measurement proble...

Understanding the behaviour of a quantum system coupled to its environment is of fundamental interest in the general field of quantum technologies. It also has important repercussions on foundational problems in physics, such as the process of decoherence and the so-called quantum measurement problem. There have been many approaches to explore Markovian and non-Markovian dynamics within the framework of open quantum systems, but the richness of the ensuing dynamics is still not fully understood. In this paper we develop a non-Markovian extension of the standard Caldeira-Leggett model, based on expanding the dynamics of the reduced system at high temperature in inverse powers of the high-frequency cut-off of the Ohmic spectral density of the environment, and derive a non-Markovian master equation for the reduced density matrix for the case of a general potential. We also obtain a fully analytical solution in the free particle case. While the short-time behaviour of this solution does not diverge substantially from the Markovian behaviour, at intermediate times we find a resurgence of coherence, which we name lateral coherence. We identify this with a corresponding transient negative entropy production rate, which is understood to be characteristic of non-Markovian dynamics. We also analyze the positivity of the reduced density matrix, and derive the corresponding Fokker-Planck equation in the classical limit.

Understanding the rules of life is one of the most important scientific endeavours and has revolutionised both biology and biotechnology. Remarkable advances in observation techniques allow us to investigate a broad range of complex and dynamic biological processes in which living systems could expl...

Understanding the rules of life is one of the most important scientific endeavours and has revolutionised both biology and biotechnology. Remarkable advances in observation techniques allow us to investigate a broad range of complex and dynamic biological processes in which living systems could exploit quantum behaviour to enhance and regulate biological functions. Recent evidence suggests that these non-trivial quantum mechanical effects may play a crucial role in maintaining the non-equilibrium state of biomolecular systems. Quantum biology is the study of such quantum aspects of living systems. In this review, we summarise the latest progress in quantum biology, including the areas of enzyme-catalysed reactions, photosynthesis, spin-dependent reactions, DNA, fluorescent proteins, and ion channels. Many of these results are expected to be fundamental building blocks towards understanding the rules of life.

Proton transfer along the hydrogen bonds of DNA can lead to the creation of short-lived, but biologically relevant point mutations that can further lead to gene mutation and, potentially, cancer. In this work, the energy landscape of the canonical A–T and G–C base pairs (standard, amino–keto) ...

Proton transfer along the hydrogen bonds of DNA can lead to the creation of short-lived, but biologically relevant point mutations that can further lead to gene mutation and, potentially, cancer. In this work, the energy landscape of the canonical A–T and G–C base pairs (standard, amino–keto) to tautomeric A–T and G–C (non-standard, imino–enol) Watson–Crick DNA base pairs is modelled with density functional theory and machine-learning nudge-elastic band methods.

One of the most important topics in molecular biology is the genetic stability of DNA. One threat to this stability is proton transfer along the hydrogen bonds of DNA that could lead to tautomerisation, hence creating point mutations. We present a theoretical analysis of the hydrogen bonds between t...

One of the most important topics in molecular biology is the genetic stability of DNA. One threat to this stability is proton transfer along the hydrogen bonds of DNA that could lead to tautomerisation, hence creating point mutations. We present a theoretical analysis of the hydrogen bonds between the Guanine-Cytosine (G-C) nucleotide, which includes an accurate model of the structure of the base pairs, the quantum dynamics of the hydrogen bond proton, and the influence of the decoherent and dissipative cellular environment. We determine that the quantum tunnelling contribution to the process is several orders of magnitude larger than the contribution from classical over-the-barrier hopping. Due to this significant quantum contribution, we find that the canonical and tautomeric forms of G-C inter-convert over timescales far shorter than biological ones and hence thermal equilibrium is rapidly reached. Furthermore, we find a large tautomeric occupation probability of 1.73×10−4

Model uncertainties arising due to suppression of target excitations in the description of deuteron scattering and resulting in a modification of the two-body interactions in a three-body system are investigated for several (d,p) reactions serving as indirect tools for studying the astrophysical (p,...

Model uncertainties arising due to suppression of target excitations in the description of deuteron scattering and resulting in a modification of the two-body interactions in a three-body system are investigated for several (d,p) reactions serving as indirect tools for studying the astrophysical (p,γ) reactions relevant to rp process.

he contribution of a three-nucleon (3N) force, acting between the neutron and proton in the incoming deuteron with a target nucleon, to the deuteron-target potential in the entrance channel of the A(d,p)B reaction has been calculated within the adiabatic distorted wave approximation (ADWA).

he contribution of a three-nucleon (3N) force, acting between the neutron and proton in the incoming deuteron with a target nucleon, to the deuteron-target potential in the entrance channel of the A(d,p)B reaction has been calculated within the adiabatic distorted wave approximation (ADWA).

In the midst of the COVID-19 pandemic, science is crucial to inform public policy. At the same time, mistrust of scientists and misinformation about scientific facts are rampant. Six scientists, actively involved in outreach, reflect on how to build a better understanding and trust of science.

In the midst of the COVID-19 pandemic, science is crucial to inform public policy. At the same time, mistrust of scientists and misinformation about scientific facts are rampant. Six scientists, actively involved in outreach, reflect on how to build a better understanding and trust of science.

Quantum biology is usually considered to be a new discipline, arising from recent research that suggests that biological phenomena such as photosynthe

Quantum biology is usually considered to be a new discipline, arising from recent research that suggests that biological phenomena such as photosynthe

A widely accepted practice for treating deuteron breakup in A(d,p)B reactions relies on solving a three-body A+n+p Schr?dinger equation with pairwise

A widely accepted practice for treating deuteron breakup in A(d,p)B reactions relies on solving a three-body A+n+p Schr?dinger equation with pairwise

The greatest physicist of the medieval era led a life as remarkable as his discoveries were prodigious, spending a decade in prison and at one point p

The greatest physicist of the medieval era led a life as remarkable as his discoveries were prodigious, spending a decade in prison and at one point p

This paper reviews the state of knowledge in the field of optics, mainly in catoptrics and dioptrics, before the birth of modern science and the well-

This paper reviews the state of knowledge in the field of optics, mainly in catoptrics and dioptrics, before the birth of modern science and the well-

The energies of the canonical (standard, amino-keto) and tautomeric (non-standard, imino-enol) charge-neutral forms of the adenine?thymine base pair (

The energies of the canonical (standard, amino-keto) and tautomeric (non-standard, imino-enol) charge-neutral forms of the adenine?thymine base pair (

In this work we compare two theoretical approaches to modeling the action of the environment on an open quantum system. It is often assumed that as th

In this work we compare two theoretical approaches to modeling the action of the environment on an open quantum system. It is often assumed that as th

The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However

The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However

The history of science is filled with examples of key discoveries and breakthroughs that have been published as landmark texts or journal papers

The history of science is filled with examples of key discoveries and breakthroughs that have been published as landmark texts or journal papers

Jim Al-Khalili describes the new experiments and theories exploring whether quantum tunnelling of hydrogen causes mutations in our DNA.

Jim Al-Khalili describes the new experiments and theories exploring whether quantum tunnelling of hydrogen causes mutations in our DNA.

We report on a model for determining spin-spin terms in the optical potential for elastic scattering of a nucleon from a target with non-zero spin. Th

We report on a model for determining spin-spin terms in the optical potential for elastic scattering of a nucleon from a target with non-zero spin. Th

The electron?ion scattering experiment ELISe is part of the installations envisaged at the new experimental storage ring at the International Facility

The electron?ion scattering experiment ELISe is part of the installations envisaged at the new experimental storage ring at the International Facility

We give a microscopic derivation of the spin-spin components of the optical potential for elastic scattering of a nucleon from a target with nonzero s

We give a microscopic derivation of the spin-spin components of the optical potential for elastic scattering of a nucleon from a target with nonzero s

The 18C spectrum has been studied in a three body n+n+16C model that includes deformation and the 2+ excitation of the 16C core as well as Pauli proje

The 18C spectrum has been studied in a three body n+n+16C model that includes deformation and the 2+ excitation of the 16C core as well as Pauli proje