The Adventure of Cold Atoms. From Optical Pumping to Quantum Gases
Conservation laws are very important in quantum physics. Two examples of applications will be given. First, optical pumping which uses transfer of angular momentum from polarized photons to atoms to produce highly polarized atomic gases. Then, laser ....
More details | Watch nowA New Kilogram in 2018: The Biggest Revolution in Metrology Since the French Revolution
Metrology - the science of measurements - is responsible for the international uniformity and precision in standards. Today, the seven units for meter, kilogram, second, ampere, kelvin, mole, and candela of our international system of units (SI units....
More details | Watch nowWhat About Redefining Time Using a Stable Laser?
Several laser-based Atomic Clocks now have an accuracy potential of ~2 x10-18, a hundred-fold better than the best achieved after more than 60 years' experience with rf resonances in Cs atoms. Still, this long attention span documents that the Cs Fou....
More details | Watch nowThe Future of Particle Physics
Elementary Particle Physics seeks to discover the basic constituents of matter and understand the fundamental forces that act on them. In this lecture I shall review the current state of particle physics, the grand success of the ñstandard modelî, ....
More details | Watch nowDiscovery of the Higgs Particle
Recently the Higgs particle has been discovered at CERN. This particle was theoretically predicted. The historical development of field theory, leading to this prediction will be discussed.
More details | Watch nowFuture Accelerators for Astro-Particle Physics
One of the most remarkable results of astro-particle Physics has been the success of the Standard Model, recently culminated in the discovery of the Higgs particle (Ho). However, the Ho is observable only in few channels at the LHC, in the presence o....
More details | Watch nowThe International Year of Light: Celebrating Fifty Years of Laser Revolution in Physics
The year 2015 has been named the International Year of Light, to mark milestones in the science of light which occurred 1000, 200, 150, 100 and 50 years go. I was a young student in physics in 1965, when the cosmic radiation background was discovered....
More details | Watch nowLight Quanta and Their Idiosyncrasies
Maxwell's electromagnetic theory (now 150 years old) seemed in its comprehensive way to be capable of answering all of the questions one might ever pose about the theory of light. But that spell was broken in 1900 by Planck's discovery that light bea....
More details | Watch nowQuantum Information: a Scientific and Technological Revolution for the 21st Century
Two of the great scientific and technical revolutions of the 20th century were the discovery of the quantum nature of the submicroscopic world, and the advent of information science and engineering. Both of these have had a profound effect not only o....
More details | Watch nowScience with Combs of Light
The spectrum of a frequency comb, commonly generated by a mode-locked femtosecond laser, consists of several hundred thousand precisely evenly spaced spectral lines. Such laser frequency combs have revolutionized the art of measuring the frequency of....
More details | Watch nowThe Origin of Elementary Particle Masses
In the beginning of the 60s, the laws of classical general relativity, Einstein's generalisation of Newtonian gravity, and of quantum electrodynamics, the quantum version of Maxwell's electromagnetic theory, were known. These laws describe long range....
More details | Watch nowOptical Microscopy – the Resolution Revolution
Throughout the 20th century it was widely accepted that a light microscope relying on conventional optical lenses cannot discern details that are much finer than about half the wavelength of light (200-400 nm), due to diffraction. However, in the 199....
More details | Watch nowDensity Functional Theory: three non-technical explanations
What do six brides have to do with Density-Functional Theory? Discover it in this lecture, in which the essential ideas behind DFT are explained in three different non-technical ways. After this practical lecture, you will be able to understand the m....
More details | Watch nowFrom Millisecond to Attosecond Laser Pulses
A historical overview is presented of the experimental development of ever shorter laser pulses from 1960 to the present. Already in the early sixties nanosecond pulses were achieved and the entry into the picosecond domain was reached in the late s....
More details | Watch nowRole of Cortical Noise in Vision
Our brains are always generating electrical signals, even if we close our eyes, plug our ears, and lie in a warm bath. These signals are called cortical noise because they don't correlate with any sensation or thought of which we are aware. I will ....
More details | Watch nowThe Individuality of Light Quanta
Light quanta are the fundamental units of radiant energy. When propagating freely they travel at the fastest attainable speed and live forever. These properties recommend them as the ideal messengers for communication of all sorts. Ordinary light ....
More details | Watch nowWhich Way For Physics?
This talk describes a new approach to the problem of characterising physical reality, one with the potential to fill in gaps in the conventional understanding of nature. It is based on a different view from the usual one of structure at the finest l....
More details | Watch nowWhat Future for Energy and Climate?
We are using the planet's fossil fuel resources in a time which is very short compared to that of human evolution. In the same process we are changing the planet's climate and sea level, threatening the future of large segments of the global populat....
More details | Watch nowThe Development of Particle Physics
Particle physics mainly developed after World War II. It has its roots in the first half of the previous century, when it became clear that all matter is made up from atoms, and the atoms in turn were found to contain a nucleus surrounded by electro....
More details | Watch nowDiscovery of Superconducting Tunneling
I had the great fortune to receive a Nobel Prize in Physics for using electron tunneling to measure the energy gap in superconductors. In this talk I will recollect some of the events that led to this discovery and hopefully I will be able to convey....
More details | Watch nowThe Optical Frequency Comb – a Really Versatile Tool
The Optical Frequency Comb concept and technology exploded in 1999-2000 from the synthesis of advances in independent fields of Laser Stabilization, UltraFast Lasers, and NonLinear Optical Fibers. The Comb was developed first as a method for optical....
More details | Watch nowTowards a Quantum Laboratory on a Chip
Microfabricated magnetic traps, waveguides, and other elements for the manipulation of ultracold atoms can be combined to form a quantum laboratory on a chip. Devices such as miniaturized atom lasers, atom interferometers, and atomic clocks have been....
More details | Watch nowCold Atomic Gases: the Intersection of Condensed Matter and Atomic Physics
During the past decade laser cooling and evaporative cooling of atoms have produced quantum degenerate gases both of bosons (Bose-Einstein condensates) and of fermions (gases with temperatures below the Fermi temperature). Such gases can provide ana....
More details | Watch nowFrom Spinwaves to Giant Magnetoresistance (GMR) and Beyond
Standing spinwaves and surface waves in layered magnetic structures can be used for the detection and quantitative evaluation of interlayer exchange coupling (IEC). Using this method antiferromagnetic IEC has been found in Fe/Cr/Fe layered structure....
More details | Watch nowCosmic Rays: the Most Energetic Particles in the Universe
Astrophysical objects are able to accelerate atomic nuclei to energies 10^7 times more than man made accelerators such as LHC. _Particles arrive at earth from space with energies as great as 50 joules, a macroscopic energy in a microscopic particle.....
More details | Watch nowThe World of Spintronics: Electrons, Spins, Computers and Telephones
Spintronics is a new field of research which exploits the influence of the electron spin on electronic transport. It is well known for the giant magnetoresistance of the magnetic multilayers and its application to increase the capacity of the hard d....
More details | Watch nowThe Big Challenges
During the entire 20th century, physical sciences have advanced to such a degree that we can extrapolate how they can be applied, even in a fairly distant future. Even if we leave open the (likely) possibility of spectacular new discoveries and inv....
More details | Watch nowFrontiers of Physics
David discusses a few of the questions facing fundamental physics that might be answered before the 100th Lindau meeting in 2050.
More details | Watch nowThe Looming World Shortage of Helium
The worldÍs supply of Helium gas comes primarily from alpha decay in rocks. The most abundant supply is in the American Southwest where it is trapped with methane is natural gas wells. That supply is estimated to last a mere 25 years. It took 4.7 bi....
More details | Watch nowThe History of the Universe, from the Beginning to the Ultimate End
John summarizes the history of the universe, from the Big Bang through the formation of galaxies and the Solar System, and the history of the Earth and some of the special factors enabling the formation of life. Our future will be hot as the Sun ge....
More details | Watch nowWhat is Quantum Optics?
The image of light waves as oscillating electromagnetic fields explains virtually all the phenomena of traditional optics. An awareness that these waves are somehow subdivided into quanta has however been with us since the early 20th century. The....
More details | Watch nowThe Development of Particle Physics
Particle physics mainly developed after World War II. It has its roots in the first half of the previous century, when it became clear that all matter is made up from atoms, and the atoms in turn were found to contain a nucleus surrounded by electro....
More details | Watch nowMapping the Universe and Its History
Using our most advanced techniques and instruments we sift through study the cosmic microwave background as a relic of the early universe to understand the events surrounding the birth and subsequent development of the Universe. A precision inspect....
More details | Watch nowWhat Can We Do with Laser Frequency Combs?
The spectrum of a frequency comb, commonly generated by a mode-locked femtosecond laser consists of several hundred thousand precisely evenly spaced spectral lines. Such laser frequency combs have revolutionized the art measuring the frequency of l....
More details | Watch nowModel Synthesis for Ceramics: Superconductors, Magnets and Others
The discovery of superconductivity in hole doped La2CuO4 was motivated by the interest to find this phenomenon in an oxide. After the discovery near 35 K, copper oxides with transition temperatures of up to 131 K at normal pressure were found, i.e.....
More details | Watch nowSuperposition, Entanglement, and Raising Schrödinger’s Cat
In 1935, Erwin Schrödinger, one of the inventors of quantum mechanics, illustrated his discomfort with the theory by pointing out that its extension to the macroscopic world could lead to bizarre situations such as a cat being simultaneously alive a....
More details | Watch nowControlling Photons in a Box and Exploring the Quantum to Classical Boundary
The founders of quantum theory assumed in 'thought experiments' that they were manipulating isolated quantum systems, obeying the counterintuitive laws which they had just discovered. Technological advances have recently turned these virtual experi....
More details | Watch nowPowering the Future
Some seeds of what to do in the climate/energy controversy are contained in what will be. In this talk I shall ask everyone to jump over contemporary politics and make a mental journey to a time, several centuries from now, when nobody uses carbon-....
More details | Watch nowSpontaneous Ionization to Subatomic Physics: Some Vignettes from Cosmic Ray History
In 1879 Crookes discovered that air seemed to ionize spontaneously. With the discovery in 1896 of radioactivity by Henri Becquerel it appeared that the mystery was solved. However a number of physicists sought a quantitative agreement between the....
More details | Watch nowThe Quantum Mechanics of Light: Interference, Entanglement – and Ghosts
The early days of the quantum theory presented many dilemmas connected with interference phenomena and what we have come to call the entanglement of states. We are much better able to deal with these problems now, both in theory and experiment, but t....
More details | Watch nowFive Decades of Lasers, Six Decades of Progress, and a Proposed Space Experiment to test Einstein’s Assumptions
Even though this is the 51st year of the Laser, progress in its control and application in precision measurements is still accelerating. The Optical Frequency Comb technology exploded in 1999-2000 from the synthesis of advances in independent field....
More details | Watch nowLaser Spectroscopy of Hydrogen
The simple Balmer spectrum of atomic hydrogen has provided the Rosetta stone for deciphering the strange laws of quantum physics during the early 20th century. Four decades ago, Doppler-free laser spectroscopy opened a new chapter in the exploratio....
More details | Watch nowA Century of Quantum Mechanics
In October 2011 we celebrated the centenary of the Solvay conferences that played a unique and important role in the development of twentieth century physics, most notably in the quantum revolution whose birth overlapped the initiation of these meeti....
More details | Watch nowThe Real M-Theory
How can one advance a working hypothesis that will not be wrong tomorrow and ridiculous the day after? Beyond the Standard Model we find uncertainty and confusion, with both unclarity as to which might be the correct theory, as well as little in the ....
More details | Watch nowCreating Artificial Magnetic Fields to Act on Neutral Atoms
Cold, quantum degenerate gases of neutral atoms have proved to be useful in simulating the behavior of quantum systems like electrons in solids. For example, cold atoms moving in optical lattices (periodic potentials created by interfering laser be....
More details | Watch nowNeutrinos: a Golden Field for Astroparticle Physics
Neutrinos have been the origin of an impressive number of ‘surprises’. We know that neutrinos have tiny masses and that oscillations are occurring spontaneously between neutrino species. But additional new discoveries may be ahead of us and t....
More details | Watch nowThe LHC at CERN and the Higgs
The strong interactions, the forces responsible for the interactions between quarks and notably supposedly responsible for quark confinement, profited from the development of gauge theories. In the wake of the gauge theory of weak interactions also....
More details | Watch nowForce or (potential) energy
Classical dynamics uses the concept of force for its solution. On the other hand force in quantum dynamics has no meaning and the concept of potential energy is used instead. The question is, "which one of the concepts is more fundamental?".
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