Posts Tagged ‘physics’
Multiverse?
Dr. Michio Kaku discussing about the universe…
Minds That Saw into God
The who-is-who of the minds that saw into the nature of God by unveiling scientific and philosophical know-how to better understand the universe. Why is it that they don’t make them like that any more?
The following picture is from the famous 5th Solvay Conference in Belgium, which brought together the greatest minds of the last century including Einstein, Curie, Schroedinger, Bohr, Heisenberg, Planck, Dirac, Pauli, Lorentz, Born, etc. The majority of the twenty-nine attendees are Nobel Prize winners.
Participants of the 5th Solvay Congress, Brussels, October 1927. The meeting was dedicated to quantum theory.
| The list of Nobel Prize winners, among those in attendance, and citations: |
- Chemistry 1936): “for his contributions to our knowledge of molecular structure through his investigations on dipole moments and on the diffraction of X-rays and electrons in gases”
- (Physics 1933): “for the discovery of new productive forms of atomic theory”
- Physics 1945): “for the discovery of the Exclusion Principle, also called the Pauli Principle”
- 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”
- Physics 1983): “for his theoretical and experimental studies of the nuclear reactions of importance in the formation of the chemical elements in the universe”
- Physics 1915): “for their services in the analysis of crystal structure by means of X-rays”
- Physics 1933): “for the discovery of new productive forms of atomic theory”
- Physics 1927): “for his discovery of the effect named after him”
- France (Physics 1929): “for his discovery of the wave nature of electrons”
- (Physics 1954): “for his fundamental research in quantum mechanics, especially for his statistical interpretation of the wavefunction”
- (Physics 1922): “for his services in the investigation of the structure of atoms and of the radiation emanating from them”
- Physics 1918): “in recognition of the services he rendered to the advancement of Physics by his discovery of energy quanta”
- Chemistry 1911): “in recognition of her services to the advancement of chemistry by the discovery of the elements radium and polonium, by the isolation of radium and the study of the nature and compounds of this remarkable element”
- (Physics 1921): “for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect”
- Physics 1928): “for his work on the thermionic phenomenon and especially for the discovery of the law named after him”
Type 1.5 Superconductivity
What distinguishes discoveries is that they unearth a new perspective to look at a problem, sometimes as long standing and well studied topic as superconductivity. Here we learn about the discovery of a new type of superconductor. It turns out that Victor Moshchalkov of the Catholic University of Leuven in Belgium and colleagues have shown that the superconductor magnesium diboride is in fact both a type-1 and type-2 superconductor, making it the first “type-1.5″ superconductor.
The vortices in the type-2 superconductor niobium diselenide form an orderly pattern (bottom); those in the "type-1.5" superconductor magnesium diboride form a disorderly pattern filled with stripes and voids
Superconductors, materials that carry electricity without resistance, can be divided into two broad groups depending on how they react to a magnetic field–or so physicists thought. New experiments show that one well-studied superconductor actually belongs to both groups at the same time. “If the experiment is true, this would add a whole new class of superconductors,” says Egor Babaev, a theorist at the University of Massachusetts, Amherst. The advance may not immediately lead to new gadgets and applications, but it suggests that superconductivity, which has already netted four Nobel Prizes, may be an even richer phenomenon that previously thought…
How can that be? Superconductors carry electricity without resistance at very low temperatures because their electrons join to make free-gliding pairs. Those electrons typically come from one of the energy “bands” within the material. Physicists have long known that magnesium diboride has two bands that produce superconductivity. One of those bands produces type-1 superconductivity and the other produces type-2 superconductivity. In a paper to be published in Physical Review Letters, Moshchalkov and colleagues argue that the interaction of the two bands yields the new kind of superconductor.
To make that case, the researchers studied the patterns of electrical vortices within a very pure, single crystal of magnesium diboride. The behavior of vortices in fact determines whether a material is a type-1 or a type-2 superconductor. In a type-2 superconductor, the vortices repel each other, so they spread out to make a lattice. In a type-1 superconductor, neighboring vortices attract each other and quickly merge to form ever larger nonsuperconducting stripes and patches.
A type-1.5 superconductor is a little of both. The vortices should repel each other at close distances but attract each other when separated by long distances. That, in turn, should lead to disordered clumps and stripes of vortices separated by large voids, according to the researchers’ simulations. And that’s exactly what they observed experimentally. The researchers did a series of controlled experiments to rule out other explanations for the weird pattern, such as inhomogeneities in the samples. “We hesitated to come to such an exciting conclusion until all other simpler explanations had been excluded,” Moshchalkov says.
If confirmed, the observation opens “an enormous number of possibilities,” says Babaev, who had predicted such a state might exist. The vortices in a type-2 superconductor can be induced to form states that are orderly, disorderly, or even flowing like a liquid. The new class of materials would likely exhibit even richer behavior and present new puzzles for theorists to tackle, Babaev says. Hermann Suderow, an experimenter at the Autonomous University of Madrid, notes that there are a few other two-band superconductors, so magnesium diboride may not be the only type-1.5 superconductor.”
Einstein Speaks!
Ever wondered how Albert Einstein would explain his infamous equation of mass-energy equivalence (E = m c 2)? Wonder no more:
Top Videos
I am usually not fond of accepting any proclamation of a Top X, you name the number, of anything at face value. There is subjectivity in the evaluation of the aesthetics and usefulness of a given item. For what it is worth, a top X listing is usually a reflection of the limit of knowledge and exposure to a body of information of the individual/group announcing it. I feel that there is certain level of pomposity in proclaiming something is a top pick in any category given the vastness of information there is in the Null Information and the limited nature of our familiarity with it. In that sense, such lists have some value in projecting what is considered to be valuable and relevant by the individual or the group. With that said, below are listings of “Top 10 Amazing Physics Videos,” “Top 10 Amazing Chemistry Videos,”and “Top 10 Amazing Biology Videos”via Wired.
The Pleasure of Finding Things Out
A series of conversations with the late Prof. Richard Feynman, a genius and thinker we can all aspire to learn from.
Why Some Ideas Go Viral and Others Do Not
In the spirit of continuing the process of correlating concepts in physics/science with that of day-to-day human behaviors, here we will discuss why some ideas go viral and others do not. The formulation presented here concerns with the idea of quantum tunneling. When a wave-like entity at a quantum scale encounters a potential barrier of a higher energy than its own, it undergoes one of the following: (1) reflection, which occurs when the entity is not able to penetrate through the barrier, (2) tunneling, which is the processes of partially-passing through the barrier, or (3) combination of both. In all cases, the ability of the wave to surpass the potential barrier is dependent on its energy level and the width of the barrier. The mathematical description of this dependence is given by: Θ ~ Exp[- √Eb³ . Xb], where Θ is the tunneling probability, Eb is the barrier height, and Xb is the barrier width. Hence, the larger the barrier height and width, the more difficult it is for the wave to penetrate through. In the event that tunneling occurs, the amplitude of the wave is diminished as it passes through the barrier.
Barrier Penetration
Now, with that rudimentary introduction to quantum tunneling, let us proceed to the postulation of what the reason behind the ease with which viral ideas spread is. Below is the graph representing the different regions of interest.
Why viral ideas spread quickly
The three distinct regions consist of the genesis, refinement, and viral-spreading of an idea/information. The vertical axis represents the potential of the idea/information to have any type of impact, which is its ability to inspire, depress, delight, annoy, revolutionize, disgust, or any other strong reaction that can make people itch until they share is with someone else. For an idea to break out of the genesis phase and go viral, it needs to overcome what I call the refinement barrier. This barrier, much like the potential barrier in the case of quantum tunneling, allows a given idea to pass through only if the width of the barrier is thin enough and the idea has the necessary potential to overcome it. In the cases where the potential is not sufficiently high, the idea/information will have to tunnel through the barrier and undergo a process of refinement. That is, the lower the potential of the idea, the more time it requires to refine. The higher the potential, the easier it is to propagate it through without much refinement. The nature of potential for impact of ideas gives a characteristic triangular-shaped barrier. Consequently, some ideas have such low potential that they are reflected right back by the refinement potential as the length of time required is simply too much to allow for the process to work. Hence, the primary factors determining the ability of an idea/information to go viral are its potential of impact and the time-length of refinement it requires. In the cases where the idea does undergo refinement, much like the wave that has a diminished amplitude, the refinement process condenses and filters the idea to make it more strong-reaction-inducing.
One wonders about the role marketing and publicity have in the spreading of an idea/information. The aforementioned analogy would dictate that there is an intrinsic potential an idea/information has to have a strong impact. No amount of advertising will change that. What the publicity will do is lower the refinement barrier height. In so doing, the probability of an idea going viral is dramatically increased. The other effect advertising can have is contracting the width of the refinement potential, which has the effect of reducing the time required for an idea to undergo the refinement process. This is accomplished by merely making more resources, e.g. number of people participating in the process, available to partake in the process. The unfortunate reality of this formulation is that if an idea/information does not have the necessary potential for impact to tunnel through the refinement barrier mostly by itself, that is, if it requires the help of major advertising push, its long-term acceptability and utility will most likely be minimal and will not last in the viral-land for a long time.
“I Am Everywhere at Once; I Have Lost My Identity…”
In an excerpt from a NOVA program on “The Race for Absolute Zero,” Prof. Daniel Kleppner of MIT explains how matter changes as it nears -459.67 °F, or absolute zero. This state of matter, the Bose-Einstein condensate, was discovered, in 1995, to exist in alkali metals at twenty-billionth of a degree (20 nK) above absolute zero by Eric Cornell, Carl Weiman and Wolfgang Ketterle. The three were awarded the 2001 Nobel Prize in Physics for this work. The citation is:
for the achievement of Bose-Einstein condensation in dilute gases of alkali atoms, and for early fundamental studies of the properties of the condensates”
- Successive occurrence of Bose-Einstein condensation in rubidium. From left to right is shown the atomic distribution in the cloud just prior to condensation, at the start of condensation and after full condensation. High peaks correspond to a large number of atoms. Silhouettes of the expanding atom cloud were recorded 6 ms after switching off the confining forces of the atom trap.
