17 research outputs found
Lightlike contours with fermions
We consider high energy scattering of open superstrings in flat spacetime. It
is shown that in this regime amplitudes are dominated by minimal supersurfaces
spanned by lightlike supercontours built of the on-shell momenta. We
demonstrate how using a generalization of the functional over
reparametrizations of the boundary one can extract the area of the minimal
supersurfaces directly from the lightlike contour. Exponent of the area
correctly reproduces RNS amplitudes. We also comment on possible implementation
of the supercontours to Wilson loops/Scattering amplitudes duality.Comment: 1+15 pages, v2 to appear in PL
A new antiviral hypothesis and radioactive iodine therapy to other cancers, such as breast cancer, lung cancer, and glioblastoma multiforme (GBM)?
Radioactive iodine therapy (RIT) is an effective, safe, and cheap method in benign and malignant thyroid diseases. There is still an unresolved question of whether RIT treatment also plays a role in the treatment of, for example, breast cancer, lung cancer, or glioblastoma multiforme (GBM). These studies are currently being carried out in rats in combination with genes, but it may be an interesting challenge to assess “pure” RIT alone, thanks to the expression of sodium iodide symporter (NIS), is effective in other organ nodules, both benign and malignant. Cloning of the NIS in 1996 provided an opportunity to use NIS as a powerful theranostic transgene. In addition, NIS is a sensitive reporter gene that can be monitored by high-resolution PET imaging using the radiolabels [124I]sodium iodide ([124I]NaI) or [18F] tetrafluoroborate ([18F]TFB). Based on published positron emission tomography (PET) results, [124I]sodium iodide and internally synthesized [18F]TFB were compared in an orthotopic animal model of NIS-expressing glioblastoma. The results showed improved image quality using [18F]TFB. Based on these results, we will be able to extend the NIS gene therapy approach using non-viral gene delivery vehicles to target orthotopic tumour models with low-volume disease such as GBM. Is it possible to treat RIT alone without using the NIS gene in GBM? After all, the NIS symporter was detected not only in the thyroid gland, but also in different tumours. The administration of RIT is completely harmless; the only complication is hypothyroidism. Indeed, recently it has been shown that, for example, in the case of thyroid cancer, the maximum RIT is 37000 MBq (1000 mCi). When beneficial effects of therapy in GBM are not possible (e.g. neurosurgery, modulated electro-hyperthermia, chemotherapy, immunotherapy, cancer vaccines, or oncolytic viruses), could RIT provide a “revolution” using NIS
Using simulation to calibrate real data acquisition in veterinary medicine
This paper explores the innovative use of simulation environments to enhance
data acquisition and diagnostics in veterinary medicine, focusing specifically
on gait analysis in dogs. The study harnesses the power of Blender and the
Blenderproc library to generate synthetic datasets that reflect diverse
anatomical, environmental, and behavioral conditions. The generated data,
represented in graph form and standardized for optimal analysis, is utilized to
train machine learning algorithms for identifying normal and abnormal gaits.
Two distinct datasets with varying degrees of camera angle granularity are
created to further investigate the influence of camera perspective on model
accuracy. Preliminary results suggest that this simulation-based approach holds
promise for advancing veterinary diagnostics by enabling more precise data
acquisition and more effective machine learning models. By integrating
synthetic and real-world patient data, the study lays a robust foundation for
improving overall effectiveness and efficiency in veterinary medicine
Krylov complexity for operators and states
I will discuss a recent notion of complexity in quantum systems called Krylov complexity. After defining it for operators as well as for states, I will present some results which test this interesting new probe in different many-body systems. This talk will be based on arXiv: 2109.03824, 2110.10519 and 2202.06957.</p
Quantum dimensions from local operator excitations in the Ising model
We compare the time evolution of entanglement measures after local operator excitation in the critical Ising model with predictions from conformal field theory. For the spin operator and its descendants we find that Rényi entropies of a block of spins increase by a constant that matches the logarithm of the quantum dimension of the conformal family. However, for the energy operator we find a small constant contribution that differs from the conformal field theory answer equal to zero. We argue that the mismatch is caused by the subtleties in the identification between the local operators in conformal field theory and their lattice counterpart. Our results indicate that evolution of entanglement measures in locally excited states not only constraints this identification, but also can be used to extract non-trivial data about the conformal field theory that governs the critical point. We generalize our analysis to the Ising model away from the critical point, states with multiple local excitations, as well as the evolution of the relative entropy after local operator excitation and discuss universal features that emerge from numerics
Entanglement entropy of extremal BTZ black holes
In this paper, we use entanglement entropy as a tool to explore the universal properties of conformal field theories (CFTs) dual to extremal BTZ black holes. We demonstrate that the entanglement entropies computed in the CFTs at the boundary of the extremal BTZ and the boundary of the near-horizon limit of the extremal BTZ are in perfect agreement and have the form appropriate to a two-dimensional CFT with only the chiral part excited and the antichiral in the ground state. Furthermore, we analyze the universal limits of the entanglement entropy and recover the correct value of the thermal entropy for large entangling intervals and the first-law-like relation for the small interval
Out-of-time-ordered correlators and purity in rational conformal field theories
In this paper we investigate measures of chaos and entanglement in rational conformal field theories in 1 + 1 dimensions. First, we derive a formula for the late time value of the out-of-time-ordered correlators for this class of theories. Our universal result can be expressed as a particular combination of the modular SS -matrix elements known as anyon monodromy scalar. Next, in the explicit setup of an SU(N)kSU(N)k Wess–Zumino–Witten model, we compare the late time behavior of the out-of-time-ordered correlators and the purity. Interestingly, in the large- cc limit, the purity grows logarithmically as in holographic theories; in contrast, the out-of-time-ordered correlators remain, in general, nonvanishing