Graham's number. Graham's number, named after Ronald Graham, is a large number that is an upper bound on the solution to a problem in Ramsey theory.
The number gained a degree of popular attention when Martin Gardner described it in the "Mathematical Games" section of Scientific American in November 1977, writing that, "In an unpublished proof, Graham has recently established ... a bound so vast that it holds the record for the largest number ever used in a serious mathematical proof. " The 1980 Guinness Book of World Records repeated Gardner's claim, adding to the popular interest in this number.
According to physicist John Baez, Graham invented the quantity now known as Graham's number in conversation with Gardner himself. While Graham was trying to explain a result in Ramsey theory which he had derived with his collaborator B. L. Graham's number is unimaginably larger than other well-known large numbers such as a googol, googolplex, and even larger than Skewes' number and Moser's number.
Context[edit] Dirac equation. In particle physics, the Dirac equation is a relativistic wave equation derived by British physicist Paul Dirac in 1928.
In its free form, or including electromagnetic interactions, it describes all spin-½ massive particles, for which parity is a symmetry, such as electrons and quarks, and is consistent with both the principles of quantum mechanics and the theory of special relativity,[1] and was the first theory to account fully for special relativity in the context of quantum mechanics. Although Dirac did not at first fully appreciate the importance of his results, the entailed explanation of spin as a consequence of the union of quantum mechanics and relativity—and the eventual discovery of the positron—represent one of the great triumphs of theoretical physics. Mathematical formulation[edit] The Dirac equation in the form originally proposed by Dirac is:[3] where ψ = ψ(x, t) is the wave function for the electron of rest mass m with spacetime coordinates x, t. Dirac's coup[edit] with.
52 Factorial. They seem harmless enough, 52 thin slices of laminated cardboard with colorful designs printed on their sides.
Yet, as another illustration of the mantra that complexity begins from the most simple systems, the number of variations that these 52 cards can produce is virtually endless. The richness of most playing card games owes itself to this fact. Permute this! Solar Magnetic Activity Cycles & Sun Weather. Our sun is apparently a happy star according to the latest video from a NASA observatory.
The video shows a pattern of sunspots that, when viewed from afar, forms a vast happy face smiling across face of the sun. Sunspots are darker, cooler patches on the sun caused when intense magnetic activity blocks heat convection. These spots are normal, but they don't usually align to give the sun's face such character. The smile on the sun is visible through 11 photographs taken by NASA's Solar Dynamics Observatory, which images the sun from Earth orbit. Each picture was taken at the same time, but through a different filter that separated out a narrow wavelength band of light. We Had No Idea What Alexander Graham Bell Sounded Like. Until Now. How Warp Speed Works" These are the biggest numbers in the universe. NEW SCIENTIST. Cookies on the New Scientist website close Our website uses cookies, which are small text files that are widely used in order to make websites work more effectively.
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SCI FI. Schwarzschild radius. The relation between properties of mass and their associated physical constants.
Every massive object is believed to exhibit all five properties. However, due to extremely large or extremely small constants, it is generally impossible to verify more than two or three properties for any object. The Schwarzschild radius (rs) represents the ability of mass to cause curvature in space and time.The standard gravitational parameter (μ) represents the ability of a massive body to exert Newtonian gravitational forces on other bodies.Inertial mass (m) represents the Newtonian response of mass to forces.Rest energy (E0) represents the ability of mass to be converted into other forms of energy.The Compton wavelength (λ) represents the quantum response of mass to local geometry.
History[edit] In 1916, Karl Schwarzschild obtained an exact solution[2][3] to Einstein's field equations for the gravitational field outside a non-rotating, spherically symmetric body (see Schwarzschild metric). Where: Quantum singularity. In science fiction, the term quantum singularity is used to refer to many different phenomena, which often approximately resemble a gravitational singularity in the scientific sense in that they are massive, localized distortions of space and time.
Oliver Heaviside.