Space has always been a primary source of inspiration for the development of the scientific, technological, artistic, philosophical and religious thinking of the whole humankind. Space explorations marked the history of the XX century, bringing an incredible technological advancement and allowing to investigate the natural phenomena over scales and into details which are simply not available on Earth. Nowadays, the Space is the benchmark of the new quantum revolution, which promises to change the way we communicate, measure and calculate, thank to the exploitation and the control of what happens at the microscopic scale. Indeed, the quantum theory, born at the beginning of the XX century to describe the behavior of the elementary particles of Nature, has reached today an incredible reliability. As any scientific theory, Quantum Mechanics is valid within the limits in which it has been experimentally verified, and the Space is the main stage where to validate quantum predictions at large scales, in a domain that is completely different with respect to the microscopic one from which it moved. The technological advances in photonics, which allows the manipulation and the control of the single quanta of light, the photons, make today feasible fundamental tests of Quantum Mechanics in Space, experiments to investigate, for example, if entanglement is preserved along thousands of kilometers or if the wave-particle duality survives even after a Space trip. Furthermore, Space makes available relativistic regimes, in which the velocities and the distances could allow to experimentally investigate the unresolved puzzle of modern physics, that is, the interplay between Quantum Mechanics and gravitation. For these reasons, this thesis is dedicated to the Quantum Optics experiment in Space I have been involved during my PhD.
Space has always been a primary source of inspiration for the development of the scientific, technological, artistic, philosophical and religious thinking of the whole humankind. Space explorations marked the history of the XX century, bringing an incredible technological advancement and allowing to investigate the natural phenomena over scales and into details which are simply not available on Earth. Nowadays, the Space is the benchmark of the new quantum revolution, which promises to change the way we communicate, measure and calculate, thank to the exploitation and the control of what happens at the microscopic scale. Indeed, the quantum theory, born at the beginning of the XX century to describe the behavior of the elementary particles of Nature, has reached today an incredible reliability. As any scientific theory, Quantum Mechanics is valid within the limits in which it has been experimentally verified, and the Space is the main stage where to validate quantum predictions at large scales, in a domain that is completely different with respect to the microscopic one from which it moved. The technological advances in photonics, which allows the manipulation and the control of the single quanta of light, the photons, make today feasible fundamental tests of Quantum Mechanics in Space, experiments to investigate, for example, if entanglement is preserved along thousands of kilometers or if the wave-particle duality survives even after a Space trip. Furthermore, Space makes available relativistic regimes, in which the velocities and the distances could allow to experimentally investigate the unresolved puzzle of modern physics, that is, the interplay between Quantum Mechanics and gravitation. For these reasons, this thesis is dedicated to the Quantum Optics experiment in Space I have been involved during my PhD.
Quantum physics experiments in space using entangled photons and satellites are within reach of current technology. We propose a series of fundamental quantum physics experiments that make advantageous use of the space infrastructure with specific emphasis on the satellite-based distribution of entangled photon pairs. The experiments are feasible already today and will eventually lead to a Bell-experiment over thousands of kilometers, thus demonstrating quantum correlations over distances which cannot be achieved by purely earth-bound experiments.
Abstract. Physical theories are developed to describe phenomena in particular regimes, and generally are valid only within a limited range of scales. For example, general relativity provides an effective description of the Universe at large length scales, and has been tested from the cosmic scale down to distances as small as 10 meters [1, 2]. In contrast, quantum theory provides an effective description of physics at small length scales. Direct tests of quantum theory have been performed at the smallest probeable scales at the Large Hadron Collider, ∼10−20 meters, up to that of hundreds of kilometers [3]. Yet, such tests fall short of the scales required to investigate potentially significant physics that arises at the intersection of quantum and relativistic regimes. We propose to push direct tests of quantum theory to larger and larger length scales, approaching that of the radius of curvature of spacetime, where we begin to probe the interaction between gravity and quantum phenomena. In particular, we review a wide variety of potential tests of fundamental physics
Physical theories are developed to describe phenomena in particular regimes, and generally are valid only within a limited range of scales. For example, general relativity provides an effective description of the Universe at large length scales, and has been tested from the cosmic scale down to distances as small as 10 meters. In contrast, quantum theory provides an effective description of physics at small length scales. Direct tests of quantum theory have been performed at the smallest probeable scales at the Large Hadron Collider, ∼10−20 meters, up to that of hundreds of kilometers. Yet, such tests fall short of the scales required to investigate potentially significant physics that arises at the intersection of quantum and relativistic regimes. We propose to push direct tests of quantum theory to larger and larger length scales, approaching that of the radius of curvature of spacetime, where we begin to probe the interaction between gravity and quantum phenomena. In particular, we review a wide variety of potential tests of fundamental physics that are conceivable with artificial satellites in Earth orbit and elsewhere in the solar system, and attempt to sketch the magnitudes of potentially observable effects. The tests have the potential to determine the applicability of quantum theory at larger length scales, eliminate various alternative physical theories, and place bounds on phenomenological models motivated by ideas about spacetime microstructure from quantum gravity. From a more pragmatic perspective, as quantum communication technologies such as quantum key distribution advance into Space towards large distances, some of the fundamental physical effects discussed here may need to be taken into account to make such schemes viable.
The turn of the XXth century witnessed a revolution in physics comparable to Isaac Newton’s discovery of the universal laws of mechanics and of gravitation three centuries earlier. The world required to be described in novel terms, as the immutable, deterministic view of our familiar universe had given way to a new world picture, one which featured chance, flux, and an incessant upsurge of waves of matter. Such a worldview was so radically new and counterintuitive that it gave rise to strong debates, to the effect that Albert Einstein himself tried to oppose it on the grounds that “God does not play dice”. In spite of the intense debates that accompanied its emergence, quantum mechanics quickly proved an incredibly efficacious new tool to understand and to predict a wide array of new phenomena. It was so successful that in no time it broke free from the environment of research labs to become part of daily life, making it possible, for example, to understand why some materials were conductors, while others were insulators. Along with it, came, too, the discovery of transistors, on which much of modern electronics rests. It also led to understand how novel materials known as superconductors allow the transport of electricity with no loss, thus paving the way for new developments in the fields of medical imagery or energy distribution. Other aspects of the quantum theory led to the development of atomic clocks of astounding accuracy, which would be wrong by no more than fifteen seconds, had they been set at the beginning of the universe. A hundred years later, at the turn of the XXIst century, Quantum mechanics has lost none of its astounding power. Contemporary research has undertaken the task of exploring its less immediately perceptible aspects. Groundbreaking developments have ensued, such as the teleportation of grains of light or the possibility, once predicted by the great physicist Richard Feynman, to build, one day, novel computers which, unlike the ones we are familiar with today, will be able to process innumerable numbers of operations in parallel. The Wright Colloquium will be for us the occasion to explore, in the company of five internationallyknown specialists in the field, some of the fascinating aspects of quantum mechanics. We will appraise how efficiently quantum physics can describe our world, and confront its limitation when it is faced with the infinitely small (in relation to recent experiments carried out at the CERN) as with the incommensurably large scale of sidereal spaces. We will appreciate the extent to which quantum physics already has impacted our everyday lives, and evoke the way in which novel fields such as quantum computers and quantum information will entail profound changes in the future. The quantum adventure has only just begun! Monday 15 November 2010 - 18h30 Jochen Mannhart Center for Electronic Correlations and Magnetism, University of Augsburg, Germany Quantum Physics on the Scale of Daily Life Tuesday 16 November 2010 - 18h30 Wolfgang Ketterle Nobel Laureate 2001 (Physics), Department of Physics, Massachusetts Institute of Technology, Cambridge, U.S.A. When freezing cold is not cold enough New forms of matter close to absolute zero temperature Wednesday 17 November 2010 - 18h30 David Gross Nobel Laureate 2004 (Physics), Kavli Institute for Theoretical Physics, University of California, Santa-Barbara, U.S.A. Quantum Mechanics of the Very, Very Small and the Very, Very Large Thursday 18 November 2010 - 18h30 Alain Aspect CNRS senior scientist and Professor Institut d'Optique and Ecole Polytechnique Palaiseau, France. From Einstein’s intuition to quantum bits: a new quantum age? Vendredi 19 novembre 2010 - 18h30 Rainer Blatt Institute of Quantum Optics and Quantum Information, Austrian Academy of Sciences and University of Innsbruck, Austria The Quantum Way of Doing Computations
Recent interest in quantum communications has stimulated great technological progress in satellite quantum technologies. These advances have rendered the aforesaid technologies mature enough to support the realization of experiments that test the foundations of quantum theory at unprecedented scales and in the unexplored space environment. Such experiments, in fact, could explore the boundaries of quantum theory and may provide new insights to investigate phenomena where gravity affects quantum objects. Here, we review recent results in satellite quantum communications and discuss possible phenomena that could be observable with current technologies. Furthermore, stressing the fact that space represents an incredible resource to realize new experiments aimed at highlighting some physical effects, we challenge the community to propose new experiments that unveil the interplay between quantum mechanics and gravity that could be realizable in the near future.This article is part of a discussion meeting issue 'Foundations of quantum mechanics and their impact on contemporary society'.
Quantum physics is the golden child of modern science. It is the basis of our understanding of atoms, radiation, and so much else, from elementary particles and basic forces to the behavior of materials. But for a century it has also been the problem child of science as it has been overwhelmed by intense disagreements between its inventors, strange paradoxes, and implications that seem like the stuff of fantasy. To understand the universe, quantum physics explores the behavior of the smallest particles in existence like quarks, electrons, and photons and which revealing a world that defies our everyday experiences and expectations. On the other hand, quantum mechanics (QM) is a fundamental theory in physics that describes the behavior of matter and energy at the atomic and subatomic levels, where classical physics fails to apply. However, the phenomena observed in QM can seem nothing short of miraculous. Physicists are trying to explain miracles of physics of universe meticulously which governed by precise scientific principles and mathematical equations. It is serious to modern technology, as its principles as well as wave-particle duality, superposition, and entanglement form the basis for electronics, computing, and medical technologies. The truth of QM in a scientific context refers to its exceptional ability to accurately describe and predict experimental results, not a philosophical ‘absolute truth’. Interestingly, the scientific elucidation of creation through quantum physics does not refute and contradict spiritual or religious narratives, rather augments our gratitude of the universe’s complexity and towards Almighty or Creator. The Bible’s or Quran’s account of creation provides a spiritual and philosophical outlook, accentuating purpose and intentionality. The precise explanations of particle behavior and cosmic formation in quantum physics, offers a balancing view grounded in empirical evidence. The purpose of this investigative study is to explore the scientific reality of QM and its purpose to depict the technical advancement for the development of modern civilization along with understand of universe in more logical way.