CASE 410 - M theory

Parallel Universes - is a 2001 documentary produced by the BBC's Horizon series. The documentary has to do with parallel universes, string theory, M theory, supergravity, and other theoretical physics concepts. Participants include Michio Kaku, Paul Steinhardt, and other physicists.



The Standard Model

Particles are considered to be points moving through space, tracing out a line called the World Line. To take into account the different interactions observed in Nature one has to provide particles with more degrees of freedom than only their position and velocity, such as mass, electric charge, color (which is the "charge" associated with the strong interaction) or spin. The standard model was designed within a framework known as Quantum Field Theory (QFT), which gives us the tools to build theories consistent both with quantum mechanics and the special theory of relativity. With these tools, theories were built which describe with great success three of the four known interactions in Nature: Electromagnetism, and the Strong and Weak nuclear forces. Furthermore, a very successful unification between Electromagnetism and the Weak force was achieved (Electroweak Theory), and promising ideas put forward to try to include the Strong force. But unfortunately the fourth interaction, gravity, beautifully described by Einstein's General Relativity (GR), does not seem to fit into this scheme. Whenever one tries to apply the rules of QFT to GR one gets results which make no sense. For instance, the force between two gravitons (the particles that mediate gravitational interactions), becomes infinite and we do not know how to get rid of these infinities to get physically sensible results.

String Theory

In String Theory, the myriad of particle types is replaced by a single fundamental building block, a `string'. These strings can be closed, like loops, or open, like a hair. As the string moves through time it traces out a tube or a sheet, according to whether it is closed or open. Furthermore, the string is free to vibrate, and different vibrational modes of the string represent the different particle types, since different modes are seen as different masses or spins. One mode of vibration, or `note', makes the string appear as an electron, another as a photon. There is even a mode describing the graviton, the particle carrying the force of gravity, which is an important reason why String Theory has received so much attention. The point is that we can make sense of the interaction of two gravitons in String theory in a way we could not in QFT. There are no infinities! And gravity is not something we put in by hand. It has to be there in a theory of strings. So, the first great achievement of String Theory was to give a consistent theory of quantum gravity, which resembles GR at macroscopic distances. Moreover String Theory also possesses the necessary degrees of freedom to describe the other interactions! At this point a great hope was created that String Theory would be able to unify all the known forces and particles together into a single `Theory of Everything'.

From Strings to Superstrings

The particles known in nature are classified according to their spin into bosons (integer spin) or fermions (odd half integer spin). The former are the ones that carry forces, for example, the photon, which carries electromagnetic force, the gluon, which carries the strong nuclear force, and the graviton, which carries gravitational force. The latter make up the matter we are made of, like the electron or the quark. The original String Theory only described particles that were bosons, hence Bosonic String Theory. It did not describe Fermions. So quarks and electrons, for instance, were not included in Bosonic String Theory. By introducing Supersymmetry to Bosonic String Theory, we can obtain a new theory that describes both the forces and the matter which make up the Universe. This is the theory of superstrings. There are three different superstring theories which make sense, i.e. display no mathematical inconsistencies. In two of them the fundamental object is a closed string, while in the third, open strings are the building blocks. Furthermore, mixing the best features of the bosonic string and the superstring, we can create two other consistent theories of strings, Heterotic String Theories.

Extra dimensions...

One of the most remarkable predictions of String Theory is that space-time has ten dimensions! At first sight, this may be seen as a reason to dismiss the theory altogether, as we obviously have only three dimensions of space and one of time. However, if we assume that six of these dimensions are curled up very tightly, then we may never be aware of their existence. Furthermore, having these so-called compact dimensions is very beneficial if String Theory is to describe a Theory of Everything. The idea is that degrees of freedom like the electric charge of an electron will then arise simply as motion in the extra compact directions! The principle that compact dimensions may lead to unifying theories is not new, but dates from the 1920's, since the theory of Kaluza and Klein. In a sense, String Theory is the ultimate Kaluza-Klein theory. For simplicity, it is usually assumed that the extra dimensions are wrapped up on six circles. For realistic results they are treated as being wrapped up on mathematical elaborations known as Calabi-Yau Manifolds and Orbifolds.

M-theory

Apart from the fact that instead of one there are five different, healthy theories of strings (three superstrings and two heterotic strings) there was another difficulty in studying these theories: we did not have tools to explore the theory over all possible values of the parameters in the theory. Each theory was like a large planet of which we only knew a small island somewhere on the planet. But over the last four years, techniques were developed to explore the theories more thoroughly, in other words, to travel around the seas in each of those planets and find new islands. And only then it was realized that those five string theories are actually islands on the same planet, not different ones! Thus there is an underlying theory of which all string theories are only different aspects. This was called M-theory. The M might stand for Mother of all theories or Mystery, because the planet we call M-theory is still largely unexplored.

CASE 409 - Drake equation

There supposidly a way to estimate the number of technologically advanced civilizations that might exist in our Galaxy. While working at the National Radio Astronomy Observatory in Green Bank, West Virginia, Dr frank Drake conceived a means to mathematically estimate the number of worlds that might harbor beings with technology sufficient to communicate across the vast gulfs of interstellar space. The Drake Equation, as it came to be known, was formulated in 1961 and is generally accepted by the scientific community.

N = R* fp ne fl fi fc L

where, • N = The number of communicative civilizations • R* = The rate of formation of suitable stars (stars such as our Sun) • fp = The fraction of those stars with planets. (Current evidence indicates that planetary systems may be common for stars like the Sun.) • ne = The number of Earth-like worlds per planetary system • fl = The fraction of those Earth-like planets where life actually develops • fi = The fraction of life sites where intelligence develops • fc = The fraction of communicative planets (those on which electromagnetic communications technology develops) • L = The "lifetime" of communicating civilizations Frank Drake's own current solution to the Drake Equation estimates 10,000 communicative civilizations in the Milky Way. Dr. Drake, who serves on the SETI League's advisory board, has personally endorsed SETI's planned all-sky survey.

Criticism

Criticism of the Drake equation follows mostly from the observation that several terms in the equation are largely or entirely based on conjecture. Thus the equation cannot be used to draw firm conclusions of any kind. As Michael Crichton, a science fiction author, stated in a 2003 lecture at Caltech: The problem, of course, is that none of the terms can be known, and most cannot even be estimated. The only way to work the equation is to fill in with guesses. [...] As a result, the Drake equation can have any value from "billions and billions" to zero. An expression that can mean anything means nothing. Speaking precisely, the Drake equation is literally meaningless... Another objection is that the very form of the Drake equation assumes that civilizations arise and then die out within their original solar systems. If interstellar colonization is possible, then this assumption is invalid, and the equations of population dynamics would apply instead. One reply to such criticisms is that even though the Drake equation currently involves speculation about unmeasured parameters, it was not meant to be science, but intended as a way to stimulate dialogue on these topics. Then the focus becomes how to proceed experimentally. Indeed, Drake originally formulated the equation merely as an agenda for discussion at the Green Bank conference. http://www.sentientdevelopments.com/2007/05/drake-equation-is-obsolete.html http://en.wikipedia.org/wiki/Drake_equation

CASE 408 - Stars and planets

Our Solar System could be called our neighborhood in our home Galaxy, the Milky Way. Our solar system has 8 planets; in order of increasing average distance from the Sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. The International Astronomy Union has an official definition for a planet. It states, "A 'planet' is defined as a celestial body that is in orbit around the Sun, has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and has cleared the neighborhood around its orbit." Pluto is a dwarf planet. Stars are balls of mostly hydrogen and helium gas that shine extremely brightly but are lightyears away from us except our sun, which is a star which eventually in around 8 billion years will explode and then spend a futher 2 billion years cooling and burning out. A star is so massive that its core is extremely dense and hot. At the high core temperatures of a star, atoms move so fast that they sometimes stick to other atoms when they collide with them, forming more massive atoms and releasing a great amount of energy. This process is known as nuclear fusion.



There are (as of June 11, 2012) 102 known multiplanetary systems (i.e. stars with at least two confirmed planets), beyond our Solar System. The star table below contains information about the coordinates, spectral and physical properties, and number of confirmed planets.



http://en.wikipedia.org/wiki/List_of_multiplanetary_systems

CASE 407 - The history of Uraguay

Uruguay,nofficially the Oriental Republic of Uruguay, sometimes the Eastern Republic of Uruguay is a country in the southeastern part of South America. It is home to 3.5 million people, of whom 1.8 million live in the capital Montevideo and its metropolitan area. An estimated 88% of the population are of European ancestry. Uruguay borders the state of Rio Grande do Sul, Brazil, to the north; and the provinces of Corrientes and Entre Ríos, Argentina to the west, limited by the Uruguay River. To the southwest, lies the estuary of the Río de la Plata. To the southeast lies the southern part of the Atlantic Ocean. With an area of approximately 68,000 sq miles, Uruguay is the second-smallest nation in South America by area. Colonia del Sacramento, one of the oldest European settlements in the country, was founded by the Portuguese in 1680. Montevideo was founded by the Spanish in the early 18th century as a military stronghold. Uruguay won its independence in 1811–28 following a three-way struggle between the claims of Spain, Argentina and Brazil. It is a constitutional democracy, with a president who is both the head of state and the head of government.



Uruguay is one of the most economically developed countries in South America, with a high GDP per capita and the 48th highest Human Development Index in the world as of 2011, and the first by human development in Latin America, when inequality is factored in. Uruguay is also noted for its low levels of corruption, being ranked by Transparency International as the second least corrupt country in Latin America (behind Chile). Its political and labor conditions are among the freest on the continent. It was the highest rated country in Latin America on Legatum's 2010 Prosperity Index. Reader's Digest ranked Uruguay as the ninth "most livable and greenest" country in the world, and first in all the Americas. Uruguay is ranked highest in Latin America on the Global Peace Index. Uruguay was the first South American country to legalize same-sex and different-sex civil unions at a national level, and to allow gay adoption. Uruguay and Bolivia were the only countries in the Americas which did not go into recession (2 consecutive quarters of retraction) as a result of the Late-2000s financial crisis. In 2009, Uruguay became the first nation in the world to provide every school child with a free laptop and internet. It was the first nation in the Americas to test hemp cultivation. Uruguay is reimbursed by the UN for the majority of its military spending, because the majority of its military is deployed as UN peacekeepers.

CASE 406 - Basf

BASF SE is the largest diversified chemical company in the world and is headquartered in Ludwigshafen, Germany. BASF originally stood for Badische Anilin- und Soda-Fabrik. Today, the four letters are a registered trademark and the company is listed on the Frankfurt Stock Exchange, London Stock Exchange, and Zurich Stock Exchange. The company delisted its ADR from the New York Stock Exchange in September 2007. The BASF Group comprises subsidiaries and joint ventures in more than 80 countries and operates six integrated production sites and 390 other production sites in Europe, Asia, Australia, Americas and Africa. Its headquarters is located in Ludwigshafen am Rhein (Rhineland-Palatinate, Germany). BASF has customers in over 200 countries and supplies products to a wide variety of industries. Despite its size and global presence BASF receives little public attention as it abandoned consumer product lines in the 90s. At the end of 2010, the company employed more than 109,000 people, with over 50,800 in Germany alone. In 2010, BASF posted sales of €63.87 billion and income from operations before special items of about €8.1 billion. The company is currently expanding its international activities with a particular focus on Asia. Between 1990 and 2005, the company invested €5.6 billion in Asia, for example in sites near Nanjing and Shanghai, China and Mangalore in India.

Chemicals

BASF produces a wide range of chemicals, for example solvents, amines, resins, glues, electronic-grade chemicals, industrial gases, basic petrochemicals and inorganic chemicals. The most important customers for this segment are the pharmaceutical, construction, textile and automotive industries.

Plastics

BASF offers a comprehensive product line and market expertise ranging from commodities to engineering and high-performance materials in thermoplastics, foams and urethanes. 1. Engineering Plastics BASF's Engineering Plastics consists of the "4 Ultras" - Ultramid polyamide (PA) nylon-based resins, Ultradur, polybutylene terephthalate (PBT), Ultraform, polyacetal (POM), and Ultrason, polysulfone (PSU) and polyethersulfone (PES). 2. Styrenics BASF Styrenics consists of the Foams and Copolymers. BASF's styrenic copolymers have applications in electronics, building and construction, and automotive components. 3. Polyurethanes BASF's Polyurethanes business consists of diverse technologies and finished products. Urethane chemicals are raw materials used in rigid and flexible foams commonly used for insulation in the construction and appliance industries, furniture, packaging and transportation. 4. Foams, Foams like Styropor are generally used as insulating materials. They are eco-efficient and offer advantages over other materials in terms of cost-effectiveness, preservation of resources and environmental protection. Investments made for insulating materials usually pay for themselves within a short time and contribute to retaining and even enhancing the value of buildings. 5. Polyamides and Intermediates BASF is a manufacturer of polyamide precursors and polyamide. BASF offer polyamide 6 and polyamide 6,6 polymers as well as precursors. 6. Biodegradable Plastics BASF was a pioneer in manufacturing and developing biodegradable plastic, namely, Ecoflex. Ecovio, consists of Ecoflex and a high content of polylactic acid.

Performance products

BASF produces a range of performance chemicals, coatings and functional polymers. These include raw materials for detergents, textile and leather chemicals, pigments and raw materials for adhesives, paper chemicals. Customers are the automotive, oil, paper, packaging, textile, sanitary products, detergents, construction materials, coatings, printing and leather industries.

Functional Solutions

BASF's Functional Solutions segment consists of the Catalysts, Construction Chemicals and Coatings divisions. These divisions develop innovative, customer-specific products and system solutions, in particular for the automotive and construction industries.

Agricultural

BASF's pesticide division supplies agricultural products and chemicals. The company produces fungicides, herbicides and insecticides including F500 (pyraclostrobin), epoxiconazole, pendimethalin, boscalid, fipronil, seed treatment products and the Clearfield Production System. The company also researchs Nutrigenomics.

Oil and gas

BASF explores for and produces oil and gas through its subsidiary Wintershall Holding AG. In Central and Eastern Europe, Wintershall works with its Russian partner Gazprom.