Found 20 talks width keyword fundamental physics

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Thursday May 5, 2022
Dr. Francesca Calore
LAPTh

Abstract

 

In this presentation, I will review the history and literature debate about the anomalous gamma-ray emission detected towards the inner Galaxy by the Fermi-LAT telescope.
The so-called Fermi GeV excess has been first discovered in the early 2010s and later characterised by several, independent, research groups. 
While its main features are well established, the details of its spectral energy distribution and morphology remain debated.
Also the nature of this anomalous signal is unknown. Different interpretations have been put forward and scrutinised.
I will provide an overview of the most promising interpretations in terms of dark matter emission and faint astrophysical sources, and offer an outlook on how we can try to disentangle these two hypotheses with multi-wavelength and multi-messenger astrophysics.

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Thursday June 3, 2021
Dr. Javier Redondo
Universidad de Zaragoza

Abstract

We introduce the strong CP problem and the existence of the Axion as a possible solution. 

We discuss the possibility that axions are the dark matter of the Universe and the possible ways to

detect it or disprove it using: direct laboratory experiments as well as astrophysical and cosmological

arguments. 

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Thursday May 13, 2021
Prof. Diego Blas
Imperial College

Abstract

Bosonic ultra-light dark matter (ULDM) in the mass range m ~ $10^{-22} - 10^{-21} \rm eV$ has been invoked as a motivated candidate with new input for the small-scale `puzzles' of cold dark matter. Numerical simulations show that these models form cored density distributions at the center of galaxies ('solitons'). These works also found an empirical scaling relation between the mass of the large-scale host halo and the mass of the central soliton. We show that this relation predicts that the peak circular velocity of the outskirts of the galaxy should approximately repeat itself in the central region. Contrasting this prediction to the measured rotation curves of well-resolved near-by galaxies, we show that ULDM in the mass range m ~ $10^{-22} - 10^{-21} \rm eV$ is in tension with the data.


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Monday November 17, 2014
Prof. Martín Rivas
Theoretical Physics Department - University of the Basque Country

Abstract

Things should be made simple, but not simpler.

What we want to show is that General Relativity, as it stands today, can be considered as a gravitational theory of low velocity spinless matter, and therefore a restricted theory of gravitation.

Gravity is understood as a geometrization of spacetime. But spacetime is also the manifold of the boundary values of the spinless point particle in a variational approach. Since all known elementary matter, baryons, leptons and gauge bosons are spinning objects, it means that the manifold, which we call the kinematical space, where we play the game of the variational formalism of a classical elementary particle must be greater than spacetime.

Mathematics shows that this manifold for any arbitrary mechanical system is always a Finsler metric space, such that the variational formalism can be interpreted as a geodesic problem on this metric space.

This manifold is just the flat Minkowski space for the free spinless particle.  Any interaction modifies its flat Finsler metric as gravitation does.

The same thing happens for the spinning objects, but now the Finsler metric space has more dimensions and its metric is modified by any interaction, so that to reduce gravity to the modification only of the metric of the spacetime submanifold is to make a simpler theory, the gravitational theory of spinless matter.

Even the usual assumption that the modification of the metric only produces a Riemannian metric of the spacetime is also a restriction because in general the coefficients for a Finsler metric, are also dependent on the velocities. Removal of the velocity dependence of metric coefficients is equivalent to consider the restriction to low velocity matter.

In the spirit of unification of all forces, gravity cannot produce, in principle, a different and simpler geometrization than any other interaction.

References: arXiv: 1203.4076


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Tuesday April 22, 2014
Dr. Martin Stringer
Instituto de Astrofisica de Canarias

Abstract

Any viable theory of the formation and evolution of galaxies should be able to broadly account for the emergent properties of the galaxy population, and their evolution with time, in terms of fundamental physical quantities. Yet, when citing the key processes we believe to be central to the story, we often find ourselves listing from a vast and confusing melee of modelling strategies & numerical simulations, rather than appealing to traditional analytic derivations where the connections to the underlying physics are more tangible. By re-examining both complex models and recent observational surveys in the spirit of the classic theories, we will investigate to what extent the trends in the galaxy population can still be seen as an elegant fingerprint of cosmology and fundamental physics.


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Friday May 27, 2011
Mr. Thomas Herbst
Institute for Quantum Optics and Quantum Information (IQOQI), University of Vienna, Vienna

Abstract

Teleportation of physical objects, transferring from one place to another without passing through intermediate locations, is not possible. However, teleportation of quantum states (the full information of quantum objects) is possible. Quantum teleportation is the faithful transfer of quantum states between systems, relying on the prior establishment of entanglement and using only classical communication during the transmission. In this talk I will first give an introduction of quantum teleportation and then present our on?going free?space quantum teleportation experiment between the two Canary Islands La Palma and Tenerife, separated by 144 km. Our scheme combines a Bell?state measurement, capable to identify two of the four Bell?states, with an actively triggered unitary transformation depending on its outcome. The scheme achieves the optimal teleportation efficiency achievable with linear optical elements. Our work is essential for showing the feasibility of satellite?based experiments and is an important step towards quantum?communication applications on a global scale.


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Friday May 20, 2011
Prof. Ramesh Narayan
Harvard-Smithsonian Center, USA.

Abstract

In his public talk, Prof. Narayan will summarize our knowledge of Black Holes in the universe. He will describe how Black Holes are discovered, how their properties are measured, and what the results mean. He will also discuss the many ways in which Black Holes influence their surroundings and the profound effect they have had on the evolution of the universe.


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Friday April 8, 2011
Dr. Javier Tejada Palacios
Catedrático de física de la materia condensada, Universidad de Barcelona

Abstract

En mi conferencia haré una introducción a la Física Cuántica y a continuación pasaré a discutir diferentes casos en los que los fenómenos cuánticos juegan un papel determinante en el trabajo de diferentes máquinas médicas. De hecho, los ejemplos que explicaré recorrerán la historia de la medicina moderna, la del siglo XX, desde el punto de vista de la terapia como de la inspección. Para todo ello tendré que echar mano, por ejemplo, del principio de incertidumbre de Heisenberg, del efecto túnel de la corriente eléctrica y del espín, de la resonancia atómica. Todo ello para explicar, entre otros casos, cómo se “ve” el corazón, cómo se detectan los pensamientos, porque el feto de la madre roba el oxígeno a la sangre de su madre para poder vivir.


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Thursday April 7, 2011
Dr. Antonio Acín
ICFO-Instituto de Ciencias Fotónicas, Barcelona, Spain

Abstract

El azar es un concepto fascinante que atrae el interés de diversas comunidades, desde filósofos a físicos y matemáticos. Por otro lado, los números aleatorios se han convertido en un recurso de gran utilidad práctica, puesto que son utilizados en, por ejemplo, aplicaciones criptográficas o la simulación de sistemas físicos y biológicos. Hasta ahora, cualquier propuesta para la generación de números aleatorios adolece de los siguientes problemas: (i) certificación: ¿cómo se puede probar que los números generados son aleatorios?, (ii) privacidad: ¿cómo se puede garantizar que los números aleatorios son aleatorios, en el sentido de impredecibles, a cualquier otro observador externo y (iii) device-independent: ¿cómo afectan las imperfecciones en los dispositivos al proceso de generación de azar? En la charla se presentará un nuevo formalismo para la generación de azar que resuelve estos tres problemas: por medio de las correlaciones no-locales de los estados entrelazados, es posible generar números cuya aleatoriedad es certificable, privada e independiente de los dispositivos.


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Thursday April 7, 2011
Dr. Manuel Aguilar Benítez de Lugo
CIEMAT, CERN

Abstract

El estudio de la radiación cósmica ha sido la herramienta fundamental para avanzar en el conocimiento del Universo. La instrumentación experimental ha sido muy variada utilizándose para su ubicación laboratorios convencionales, globos sonda, satélites y plataformas espaciales. Está previsto que en 2011 la Estación Espacial Internacional esté totalmente operativa y disponible para la realización de medidas precisas y de larga duración de las componentes electromagnética y cargada de la radiación cósmica en ausencia de contaminación atmosférica. Una colaboración internacional ha construido un detector de física de partículas elementales, el espectrómetro AMS−02, para la realización de este tipo de medidas, algunas de las cuales tienen extraordinario interés en Astrofísica de Partículas, una disciplina científica fronteriza entre la Física de Partículas Elementales, la Astrofísica de Altas Energías y la Cosmología. En la planificación de la NASA este instrumento será enviado a la Estación Espacial en el año 2011. En esta conferencia se describirá la Estación Espacial Internacional (ISS) y el programa científico de AMS−02, en particular la búsqueda de antimateria cósmica primaria y la posible observación de señales de materia oscura.


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