Precursors of non-Markovianity

Using the paradigm of information backflow to characterize a non-Markovian evolution, we introduce so-called precursors of non-Markovianity, i.e. necessary properties that the system and environment state must exhibit at earlier times in order for an ensuing dynamics to be non-Markovian. In particular, we consider a quantitative framework to assess the role that established system-environment correlations together with changes in environmental states play in an emerging non-Markovian dynamics. By defining the relevant contributions in terms of the Bures distance, which is conveniently expressed by means of the quantum state fidelity, these quantities are well defined and easily applicable to a wide range of physical settings. We exemplify this by studying our precursors of non-Markovianity in discrete and continuous variable non-Markovian collision models.Comment: 9 pages, 4 figures. Close to published versio

Entropy production and correlations in a controlled non-Markovian setting

We study the relationship between (non-)Markovian evolutions, established correlations, and the entropy production rate. We consider a system qubit in contact with a thermal bath and in addition the system is strongly coupled to an ancillary qubit. We examine the steady state properties finding that the coupling leads to effective temperatures emerging in the composite system, and show that this is related to the creation of correlations between the qubits. By establishing the conditions under which the system reaches thermal equilibrium with the bath despite undergoing a non-Markovian evolution, we examine the entropy production rate, showing that its transient negativity is a sufficient sign of non-Markovianity.Comment: 8 pages, 4 figures. Close to published versio

A Phenomenological Exploration of Young Adults Who Self-Identify with Primary Complex Motor Stereotypies

Primary complex motor stereotypies (p-CMS) are repetitive, rhythmic, and predictable involuntary movements which occur in typically developing individuals. To date, research has focused on observational data involving parents, leaving a lack of first-hand information about the effect of p-CMS on experiencers’ quality of life and wellbeing in adulthood. This phenomenological study, grounded in Bronfenbrenner’s ecological theory, explored lived experiences of six young adults, ages 21 to 29 years, who self-identified with p-CMS, through in-depth telephone and Zoom interviews. I aimed to answer how p-CMS affected participants in academic, work, and social settings, what meaning participants assigned to their p-CMS, and what participants wished family, doctors, and teachers would know about p-CMS as a social phenomenon. Data were analyzed through the application of Colaizzi’s method of data analysis in combination with open and axial coding. Participants viewed p-CMS as mostly positive and serving a definite purpose in terms of emotional and learning processing, while indicating that p-CMS manifestations needed less focus from caregivers and medical/mental health personnel and underlying comorbidities required more focus. Results of the study revealed unobservable firsthand experiences of p-CMS, the role of p-CMS in processing and regulation of emotional and academic information, and effect of comorbidities. Implications for positive social change include more informed insight by caregivers, family, medical personnel, and teachers into the role of p-CMS on experiencers’ lives and development of future treatments and approaches

Quantum heat statistics with time-evolving matrix product operators

Funding: We acknowledge funding from the European Research Council under the European Union’s Horizon 2020 research and innovation program (ODYSSEY Grant Agreement No. 758403). J.G.is grateful for support from a SFI-Royal Society University Research Program. We also acknowledge support from the EPSRC, under Grant No. EP/T014032/1. A.S. acknowledges support the Australian Research Council Centres of Excellence for Engineered Quantum Systems (EQUS, CE170100009).We present a numerically exact method to compute the full counting statistics of heat transfer in non-Markovian open quantum systems, which is based on the time-evolving matrix product operator (TEMPO) algorithm. This approach is applied to the paradigmatic spin-boson model in order to calculate the mean and fluctuations of the heat transferred to the environment during thermal equilibration. We show that system-reservoir correlations make a significant contribution to the heat statistics at low temperature and present a variational theory that quantitatively explains our numerical results. We also demonstrate a fluctuation-dissipation relation connecting the mean and variance of the heat distribution at high temperature. Our results reveal that system-bath interactions make a significant contribution to heat transfer even when the dynamics of the open system is effectively Markovian. The method presented here provides a flexible and general tool to predict the fluctuations of heat transfer in open quantum systems in non-perturbative regimes.Publisher PDFPeer reviewe

Amalgame: Cosmological Constraints from the First Combined Photometric Supernova Sample

Future constraints of cosmological parameters from Type Ia supernovae (SNe Ia) will depend on the use of photometric samples, those samples without spectroscopic measurements of the SNe Ia. There is a growing number of analyses that show that photometric samples can be utilised for precision cosmological studies with minimal systematic uncertainties. To investigate this claim, we perform the first analysis that combines two separate photometric samples, SDSS and Pan-STARRS, without including a low-redshift anchor. We evaluate the consistency of the cosmological parameters from these two samples and find they are consistent with each other to under $1\sigma$. From the combined sample, named Amalgame, we measure $\Omega_M = 0.328 \pm 0.024$ with SN alone in a flat $\Lambda$CDM model, and $\Omega_M = 0.330 \pm 0.018$ and $w = -1.016^{+0.055}_{-0.058}$ when combining with a Planck data prior and a flat $w$CDM model. These results are consistent with constraints from the Pantheon+ analysis of only spectroscopically confirmed SNe Ia, and show that there are no significant impediments to analyses of purely photometric samples of SNe Ia.Comment: Submitting to MNRAS; comments welcom

Pharmacokinetics of Intra-Arterial Melphalan in Patients withRecurrent or Progressive Retinoblastoma Treated on Spog-Rb-2011, A NationalPhase II Study of the Swiss Paediatric Oncology Group

Since the 1990s, intravenous (iv) chemotherapy has been the system-atic first-line treatment used in the management of retinoblastoma, to reduce tumour volumeand render it accessible to focal treatments as well as to avoid enucleation and/or radiother-apy. This approach has allowed globe preservation in the majority of group A-C tumors and in19-60% of group D cases. Relapse or tumour progression in this group D patients constitute amajor concern for globe salvage. Techniques of local administration of chemotherapy, such asSelective Ophtalmic Artery Chemotherapy (SOAC) administration offers an interesting alter-native. We report here pharmacokinetic analysis of melphalan administered by SOAC in eightpatients, their clinical response to SOAC and observed toxicities