III Quantum Rio Workshop

quantum Rio

Despite of all difficulties of the present, and uncertainties of the future, it is time to gather the quantum info community/family from Rio. The quantum Rio Workshop, now in its third edition, will take place at CBPF from the 5th to the 6th of November. See the tentative schedule below. More information at https://quantumrio.wordpress.com/iii-quantum-rio-workshop/

We hope to see all the family there!

Coordinates: Auditorium 6th floor, CBPF.

Dates: 05/11 and 06/11

Program:

Monday (05/11) Tuesday (06/11)
10h00 — 10h30 Welcome Coffee Welcome Coffee
10h30 — 11h00 José Augusto Fernando Nicácio
11h00 — 11h30 Frederico B. Brito Reinaldo Faria
11h30 — 12h00 Alexandre Martins Thiago Guerreiro
12h00 — 14h00 Lunch Lunch
14h00 — 14h30 Ranieri Nery Ernesto Galvão
14h30 — 15h00 Carlos Eduardo Alfredo Ozorio
15h00 — 16h00 coffee-break + poster coffee-break + poster
16h00h — 16h30 Stephen Walborn Eduardo Duzzioni
16h30h — 17h00 Fernando de Melo Antônio Zelaquett

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QM Talks@CBPF: Diney Ether — 10/10, 16h00

The 2018 Physics Nobel Prize was awarded “for groundbreaking inventions in the field of laser physics”. Among these inventions are the optical tweezers, which will play an important role in our next QM Talks@CBPF. This week we are pleased to welcome Diney Ether (UFRJ), who is employing optical tweezers to measure very feeble forces due to the Casimir effect. See details below, and be sure to be there!

Title: Perspectives: Probing the Casimir Effect using Optical Tweezers

Speaker: Diney Ether (UFRJ)

Coordinates: room t.b.a, CBPF. 10/10, 16h00

Abstract:
We propose to use optical tweezers to probe the Casimir interaction between microspheres inside a liquid medium. This setup has the potential for revealing unprecedented features associated either with the Casimir force screening by movable ions in solution and the non-trivial role of the spherical curvatures achieved by going beyond the validity of the widely employed proximity force approximation. We will show some current experimental results with polystyrene microspheres immersed in water at distances below 500nm by employing very soft optical tweezers, with stiffness in the scale of fN/nm. Finally, we also described some theoretical results and future perspectives to suppress the electrostatic double-layer force always present in this context, and some theoretical results concerning light reverberation between the microspheres. This line of investigation has the potential for bringing together different fields including classical and quantum optics, statistical physics and colloidal science, while paving the way for novel quantitative applications of optical tweezers in cell and molecular biology.

References:

D. S. Ether, L. B. Pires et al, EPL 112, 44001 (2015).
D. S. Ether, F. S. S. Rosa et al, PRE 97, 022611 (2018).

4a Escola Avançada de Física Experimental do CBPF

Estão abertas as inscrições para 4a Escola Avançada de Física Experimental (EAFExp) do CBPF!

Nesta escola estudantes de graduação e de pós-graduação têm a oportunidade de entrar em contato com os pesquisadores do CBPF e suas linhas de pesquisa, além de entrarem em contato com diversas técnicas experimentais em diferentes áreas da Física.

Na EAFExp os alunos são separados em pequenos grupos e cada grupo é inserido em apenas um módulo (curso) da escola. Assim, os estudantes têm a oportunidade de conhecer a fundo como são as atividades de pesquisa de um físico experimental. Esta característica faz desta uma escola especial onde os estudantes selecionados passam duas semanas realizando atividades de pesquisa que incluem o planejamento dos estudos experimentais a serem realizados, realização dos experimentos em equipamentos de última geração, análise de dados e apresentação de seminários relatando seus resultados para professores e outros estudantes da própria escola.

A 4a EAFExp ocorrerá entre 4 e 15 de fevereiro de 2019. As inscrições se encerram no dia 15 de novembro de 2018.

Contato: eafexp@cpbf.br

Home page: www.cbpf.br/eafexp/

QM Talks@CBPF: Diogo O. Soares-Pinto — 26.09, 14h00

Title: Time, coherence and quantum reference frames

Speaker: Diogo O. Soares-Pinto (USP-SC)

Coordinates: COEDU meeting room, 6th floor, CBPF. 26.09, 14h00

Abstract: The Page and Wootters’ mechanism questioned the fundamental nature of time in quantum physics. The mechanism explored the notion that a given physical quantity is always defined and measured relative to a reference frame, in general, not explained in the theoretical description of quantum physical experiments. Recently, the new area of quantum information theory named resource theory of asymmetry deals explicitly with what are the physical conditions for a quantum system to serve as a good reference frame. In this work, we use this machinery in the Page and Wootters’ mechanism by identifying the concept of local time-asymmetry as relative coherence and establishing an operational theory of relative coherence in a composed quantum systems. To do so, the notion of quantum coherence in relation of a quantum reference frame is revisited and a quantifier is proposed in this scenario. Also, this open space to investigate the link of relative coherence and correlations, as proposed by Page and Wootters, under a resource theory approach.

New article: Quantum revival patterns from classical phase-space trajectories

Title: Quantum revival patterns from classical phase-space trajectories

Authors: Gabriel M. Lando, Raúl O. Vallejos, Gert-Ludwig Ingold, Alfredo M. Ozorio de Almeida

Link: https://arxiv.org/abs/1809.04139

Abstract: A general semiclassical method in phase space based on the final-value representation of the Wigner function is discussed that bypasses caustics and the need to search for classical trajectories. We demonstrate its potential by applying the method to the Kerr Hamiltonian. Fractional revivals sensitive to details in the quantum evolution are obtained semiclassically and provide decisive evidence for the validity of the approach far beyond the Ehrenfest time. There is no constraint on the initial state as is shown by reproducing fractional revivals not only for the usual coherent states but also for a shifted weakly excited Fock state.

“O que uma disputa entre Einstein e Bohr pode ensinar à era da pós-verdade”, Fernando de Melo (Folha de SP, 1/9/2018)

quantum Rio

Hoje foi publicado na Folha de São Paulo um belo texto do Fernando de Melo (CBPF), descrevendo a gênese da mecânica quântica como exemplo da importância do debate baseado em fatos, em contraposição à era atual dos “fake news” e pós-verdade. Confiram aqui!

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Q-turn: deadline for submissions extended!

quantum Rio


Dear quantum colleagues,

By popular demand, the submission deadline for contributed talks and posters for the Q-turn workshop, Florianópolis, Brazil has been extended to *September 7* (Anywhere On Earth). Furthermore, the super-early bird registration deadline has been extended to *September 8*!

Q-turn will feature a program of contributed talks and posters in the areas quantum information, computation, foundations and intersecting areas (e.g., many body theory or quantum optics). A generous number of travel support is available (application deadline is *September 8*).

Talk submissions should be a (max) 3-page description of the work. It is encouraged that applications include a link to a published paper or preprint. To submit your work for a talk or poster visit our webpage: https://qturnworkshop.wixsite.com/2018/apply

As well as a scientific program, Q-turn will feature 5 talks and discussions on issues that affect the quantum information community, ranging from diversity and inclusion, health and mental health, to…

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