Presented by: Ashraf Gouda Nobel prize in physics The Nobel Prize in Physics has been awarded to 180 individuals since 1901. (John Bardeen was awarded the prize in both 1956 and 1972.( Noble Prize In Physics- Ashraf Gouda Presented by: Ashraf Gouda

What Is physics? (and why should you care?) Physics is the study of the basic physical world It addresses “How” and “Why” questions It explains and predicts how the universe works. Physics is key to scientific literacy Understanding physics is useful in every day life Leaving physical problem to other is expensive Modern technological society depend on physics.

The Nobel Prize in Physics 1901 "in recognition of the extraordinary services he has rendered by the discovery of the remarkable rays subsequently named after him“ Wilhelm Conrad Röntgen Germany

X-rays How Are X-rays Made? The penetrating rays discovered by Röntgen in 1895.   X-rays, What Are They? electromagnetic waves of shorter wavelength and higher energy than normal light But the debates over the nature of the rays – waves or particles? continued until the wave-particle duality was generally accepted in the 1920s. Photons can be described both as waves and particles.

X-rays in Use

The Nobel Prize in Physics 1902 "in recognition of the extraordinary service they rendered by their researches into the influence of magnetism upon radiation phenomena“ Hendrik Antoon Lorentz the Netherlands Pieter Zeeman

Zeeman effect Is the splitting of a spectral line into several components in the presence of a static magnetic field Since the distance between the Zeeman sub-levels is proportional to the magnetic field, this effect is used by astronomers to measure the magnetic field of the Sun and other stars.

Lorentz transformation converts between two different observers' measurements of space and time, where one observer is in constant motion with respect to the other Time is different from frame to another You can’t transfer energy with a v greater than c

The Nobel Prize in Physics 1903 "in recognition of the extraordinary services he has rendered by his discovery of spontaneous radioactivity" "in recognition of the extraordinary services they have rendered by their joint researches on the radiation phenomena discovered by Professor Henri Becquerel“ Antoine Henri Becquerel 1/2 Pierre Curie 1/4 Marie Curie 1/4 France

Radioactive decay Radioactive decay is the process in which an unstable atomic nucleus loses energy by emitting radiation in the form of particles or electromagnetic waves

The Nobel Prize in Physics 1906 "in recognition of the great merits of his theoretical and experimental investigations on the conduction of electricity by gases“ Joseph John Thomson United Kingdom

Work on cathode rays Cathode Rays Tube (CRT) In his first experiment, he investigated whether or not the negative charge could be separated from the cathode rays by means of magnetism In his second experiment, he investigated whether or not the rays could be deflected by an electric field In his third experiment, Thomson measured the charge-to-mass ratio of the cathode rays by measuring how much they were deflected by a magnetic field and how much energy they carried Application: Cathode Rays Tube (CRT)

The Nobel Prize in Physics 1909 "in recognition of their contributions to the development of wireless telegraphy“ Guglielmo Marconi Italy Karl Ferdinand Braun Germany

Invention of radio Marconi began to conduct experiments, building much of his own equipment in the attic of his home at the Villa Griffone in Pistachio, Italy. His goal was to use radio waves to create a practical system of "wireless telegraphy”. Marconi's system had the following components A relatively simple oscillator. A wire or capacity area placed at a height above the ground; A coherer receiver A telegraph key to operate the transmitter to send short and long pulses, corresponding to the dots-and-dashes of Morse code A telegraph register, activated by the coherer, which recorded the transmitted Morse code dots-and-dashes onto a roll of paper tape.

The Nobel Prize in Physics 1915 "for their services in the analysis of crystal structure by means of X-rays“ Sir William Henry Bragg United Kingdom William Lawrence Bragg

X-ray crystallography Diffraction from a three dimensional periodic structure such as atoms in a crystal is called Bragg diffraction.

The Nobel Prize in Physics 1918 "in recognition of the services he rendered to the advancement of Physics by his discovery of energy quanta“ Max Karl Ernst Ludwig Planck Germany

Quantum Mechanics: The word “quantum” (Latin, “how much”) in quantum mechanics refers to a discrete unit that quantum theory assigns to certain physical quantities, such as the energy of an atom at rest .The discovery that waves have discrete energy packets (called quanta) that behave in a manner similar to particles . E = h v

The Nobel Prize in Physics 1921 "for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect“ Albert Einstein Germany and Switzerland

Photoelectric effect The photoelectric effect is a quantum electronic phenomenon in which electrons are emitted from matter after the absorption of energy from electromagnetic radiation such as x-rays or visible light. The emitted electrons can be referred to as photoelectrons in this context. Study of the photoelectric effect led to important steps in understanding the quantum nature of light and electrons and influenced the formation of the concept of wave–particle duality. Applications:??

Special theory of relativity First postulate: The laws of physics are the same in all inertial frames of reference. Second postulate: The speed of light in a vacuum is a universal constant, c, which is independent of the motion of the light source. c (299792458 m/s) Time dilation (twin paradox) Lorentz contraction Equivalence of mass and energy, E = mc^2

The Nobel Prize in Physics 1922 "for his services in the investigation of the structure of atoms and of the radiation emanating from them“ Niels Henrik David Bohr Denmark

Bohr model In atomic physics, the Bohr model depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus — similar in structure to the solar system, but with electrostatic forces providing attraction, rather than gravity. The electrons travel in orbits that have discrete quantized speeds, and therefore quantized energies. That is, not every orbit is possible but only certain specific ones, at certain specific distances from the nucleus. The electrons do not continuously lose energy as they travel. They can only gain and lose energy by jumping from one allowed orbit to another.

The Nobel Prize in Physics 1927 "for his discovery of the effect named after him" "for his method of making the paths of electrically charged particles visible by condensation of vapor” Arthur Holly Compton USA Charles Thomson Rees Wilson United Kingdom

Compton scattering In physics, Compton scattering or the Compton effect is the decrease in energy (increase in wavelength) of an X-ray or gamma ray photon, when it interacts with matter

The Nobel Prize in Physics 1929 "for his discovery of the wave nature of electrons“ Prince Louis-Victor Pierre Raymond de Broglie France

De Broglie hypothesis all matter (any object) has a wave-like nature (wave-particle duality). He suggested that the wave-particle dualism that applies to EM radiation also applies to particles of matter. He proposed that every kind of particle has both wave and particle properties.  Hence, electrons can be thought of as either particles or waves. 

The Nobel Prize in Physics 1932 "for the creation of quantum mechanics, the application of which has, inter alia, led to the discovery of the allotropic forms of hydrogen“ Werner Karl Heisenberg Germany

Uncertainty principle which lays it down that the determination of the position and momentum of a mobile particle necessarily contains errors the product of which cannot be less than the quantum constant h and that, although these errors are negligible on the human scale, they cannot be ignored in studies of the atom.

The Nobel Prize in Physics 1933 "for the discovery of new productive forms of atomic theory“ Erwin Schrödinger Austria Paul Adrien Maurice Dirac United Kingdom

Atomic theory In chemistry and physics, atomic theory is a theory of the nature of matter, which states that matter is composed of discrete units called atoms, as opposed to obsolete beliefs that matter could be divided into any arbitrarily small quantity. Or, in a nutshell, the idea that all things are made of atoms. The chemists of the era believed the basic units of the elements were also the fundamental particles of nature and named them atoms (derived from the Greek word atomos, meaning "indivisible"). However, around the turn of the 20th century, through various experiments with electromagnetism and radioactivity, physicists discovered that the so-called "indivisible atom" was actually a conglomerate of various subatomic particles (chiefly, electrons, protons and neutrons) which can exist separately from each other.

Schrödinger equation Solutions of the analytical solutions of the time-independent Schrödinger equation can be obtained for a variety of relatively simple conditions. These solutions provide insight into the nature of quantum phenomena and sometimes provide a reasonable approximation of the behavior of more complex systems (e.g., in statistical mechanics, molecular vibrations are often approximated as harmonic oscillators).

The Nobel Prize in Physics 1935 "for the discovery of the neutron“ James Chadwick United Kingdom

The Nobel Prize in Physics 1956 "for their researches on semiconductors and their discovery of the transistor effect“ William Bradford Shockley USA John Bardeen Walter Houser Brattain

Vacuum Tubes: The vacuum tube that hundred years ago only had a role in scientists' exploration of the processes in matter, has, thanks to many technical inventions, evolved into an apparatus that is found in virtually every home and office – the television tube and the computer screen.

First transistor

Solid-state transistor Since then semiconductor devices have evolved tremendously. Today transistors are extremely small and come packed in millions onto tiny Silicon chips called integrated circuits This invention is essential for digital technologies like computers, mobile phones, CDs, mp3s or DVDs. The list could be made almost infinite. For instance, without semiconductor technology there would be no Internet, so you would not be able to read this text. Actions of transistor: Switches Amplifiers How many transistors on the Pentium 4??

The Nobel Prize in Physics 1969 "for his contributions and discoveries concerning the classification of elementary particles and their interactions“ Murray Gell-Mann USA BibAlex

The Nobel Prize in Physics 1973 "for their experimental discoveries regarding tunneling phenomena in semiconductors and superconductors, respectively" "for his theoretical predictions of the properties of a supercurrent through a tunnel barrier, in particular those phenomena which are generally known as the Josephson effects“ Leo Esaki Japan BibAlex Ivar Giaever USA Brian David Josephson United Kingdom

The Nobel Prize in Physics 1985 "for the discovery of the quantized Hall effect“ Klaus von Klitzing Federal Republic of Germany bibalex

The Nobel Prize in Physics 1996 "for their discovery of superfluidity in helium-3“. David M. Lee USA Douglas D. Osheroff BibAlex Robert C. Richardson

The Nobel Prize in Physics 1999 "for elucidating the quantum structure of electroweak interactions in physics“ Gerardus 't Hooft the Netherlands bibalex Martinus J.G. Veltman

The Nobel Prize in Physics 2006 "for their discovery of the blackbody form and anisotropy of the cosmic microwave background radiation“ John C. Mather USA George F. Smoot

The Nobel Prize in Physics 2007 "for the discovery of Giant Magnetoresistance“ Albert Fert France Peter Grünberg Germany

Hard Disks: Portable computers, music players, and powerful search engines, all require hard disks where the information is very densely packed. Information on a hard disk is stored in the form of differently magnetized areas A certain direction of magnetization corresponds to the binary zero, and another direction corresponds to the binary value of one. In order to access the information, a read-out head scans the hard disk and registers the different fields of magnetization. When hard disks become smaller, each magnetic area must also shrink. This means that the magnetic field of each bite becomes weaker and harder to read. A more tightly packed hard disk thus requires a more sensitive read-out technique Recently, the maximum storage capacity of hard disks for home use has soared to a terabyte (a thousand billion bytes).

In a metal conductor, electricity is transported in the form of electrons which can move freely through the material. The current is conducted because of the movement of electrons in a specific direction, the straighter the path of the electrons, the greater the conductance of the material

In a magnetic material the scattering of electrons is influenced by the direction of magnetization. The very strong connection between magnetization and resistance that one finds in giant magnetoresistance arises because of the intrinsic rotation of the electron that induces a magnetic moment – the quantum mechanical property called spin – which is directed in either one of two opposite directions

In the following an example of the simplest type of system where giant magnetoresistance can arise is described: It consists of a layer of non-magnetic metal sandwiched between two layers of a magnetic metal

References http://nobelprize.org/nobel_prizes/physics/laureates/ http://en.wikipedia.org