Physics, Computer and Information Mahmoud Abdel-Salam, IT dept., Faculty of Computer and Information System, Mansoura University, [email protected], [email protected] Computers Today! • we are surrounded by computers these days, from smart phones, to LCD displays and etc., we rarely tend to look at all the physics that are happening inside all of these computers Physical Components of Computer • Motherboard (System board – Main board): • The main circuit board of a PC • Computer systems plug directly into the system board. • CPU is normally housed on your system board • Other items are attached to the system board, either directly or via cables. • The motherboard is considered the central nervous system in the computer. Physical Components of Computer • Chipset: • The chipset is a series of chips attached directly to the motherboard • Controls the system and its capabilities. • All components communicate with the processor through the chipset • Chipsets are not upgradeable without a new motherboard Physical Components of Computer Moore's law • The number of transistors on integrated circuits doubles approximately every two years. • Which results in: • faster execution • higher storage capacity. Physical information • Information itself defined as "that which can distinguish one thing from another". • Physical information refers to information that is contained in a physical system. Physical information • A holder of information is a variable can have different forms at different times. • A piece of information is a particular fact about a thing's identity or properties. • A pattern of information (or form) is the pattern or content of an instance or piece of information. Physical information • An embodiment of information is the thing whose essence is a given instance of information. • A representation of information is an encoding of some pattern of information within some other pattern or instance. Physical information • An interpretation of information is a decoding of a pattern of information as being a representation of another specific pattern or fact. • An amount of information is a quantification of how much of a given system's information content. Physical information and entropy • Entropy is simply that portion of the physical information contained in a system. • Quantifying classical physical information: • For a system S, defined abstractly in such a way that it has N distinguishable states, the amount of information I(S) contained in the system can be said to be log(N). Physical information and entropy • if subsystem A has N distinguishable states and an independent subsystem B has M distinguishable states, then the concatenated system has NM distinguishable information content I(AB) = log(NM) = log(N) + log(M) = I(A) + I(B). Digital physics • digital physics is a collection of physical theories in the universe that described by information, and is therefore computable. • is essentially informational and digital • is essentially computable • can be described digitally • is itself a computer Quantum computer • A quantum computer is a computation device that makes direct use of quantum-mechanical phenomena, such as superposition to perform operations on data. • digital computers require data to be encoded into binary digits (bits), quantum computation uses qubits (quantum bits), which Quantum computer • A theoretical model is the quantum Turing machine. • Quantum superposition is a fundamental principle of quantum mechanics that holds physical system. • It is the ability of a quantum system to be in multiple states at the same time. Quantum computer • The quantum properties can be used to represent and structure data to perform operations with this data. • large-scale quantum computers can be built, they will be able to solve certain problems exponentially faster than any of our current classical computers. Optical computing • Optical or photonic computing uses photons produced by lasers or diodes for computation. • Photons promise to allow a higher bandwidth than the electrons used in conventional computers. DNA Computer • A nanocomputer that uses DNA to store information and perform complex calculations. • DNA could be used to solve complex mathematical problems. • Adelman found a way to harness the power of DNA to solve the Hamiltonian path problem (the traveling salesman problem). DNA Computer • The main benefit of using DNA computers to solve complex problems is that different possible solutions are created all at once (known as parallel processing) • Humans and most electronic computers must attempt to solve the problem one process at a time (linear processing/serially). • DNA are of being a cheap, energy-efficient Nanotechnology • Nanotechnology is science, engineering, and technology conducted at the nanoscale. • Nanoscience and nanotechnology are the study and application of extremely small things and can be used across all the other science fields, such as chemistry, biology, physics, materials science, and engineering.