The Dirac large numbers hypothesis refers to an observation made by Paul Dirac in 1937 relating ratios of size scales in the universe to that of force scales. Dirac noted that the ratio of the size of the visible universe, ct with c the speed of light and t the age of the Universe, to the size of a quantum particle r is about . Hence in units c = 1 and r = 1 this large number can be taken as the age of the Universe, . Paul Adrien Maurice Dirac Paul Adrien Maurice Dirac, (August 8, 1902 – October 20, 1984) was a British theoretical physicist and a founder of the field of quantum physics. ... 1937 was a common year starting on Friday (link will take you to calendar). ... The deepest visible-light image of the cosmos. ... Cherenkov effect in a swimming pool nuclear reactor. ... The age of the Universe is defined as the largest possible value of proper time integrated along a timelike curve from the Earth at the present epoch back to the Big Bang. ... Fig. ...

There is another ratio with this order of magnitude: the ratio of the electrical to the gravitational forces between two protons, . Hence, taking the charge e of the electron and the mass m of the proton as units, the gravitational constant equals . Dirac interpreted this to mean that G varies with time as and built what remains to this day a largely untested cosmology out of this idea . If correct, the connection between gravity and quantum mechanics would be unmistakable and may point in the direction of a theory of quantum gravity. An order of magnitude is the class of scale or magnitude of any amount, where each class contains values of a fixed ratio to the class preceding it. ... Electromagnetism is the physics of the electromagnetic field: a field, encompassing all of space, composed of the electric field and the magnetic field. ... This article covers the physics of gravitation. ... In physics, a force is an external cause responsible for any change of a physical system. ... For alternative meanings see proton (disambiguation). ... Electric charge is a fundamental conserved property of some subatomic particles, which determines their electromagnetic interactions. ... Properties The electron is a subatomic particle. ... Mass is a property of physical objects that, roughly speaking, measures the amount of matter they contain. ... Properties In physics, the proton (Greek proton = first) is a subatomic particle with an electric charge of one positive fundamental unit (1. ... According to the law of universal gravitation, the attractive force between two bodies is proportional to the product of their masses and inversely proportional to the square of the distance between them. ... Cosmology, from the Greek: κοσμολογία (cosmologia, κόσμος (cosmos) world + λογια (logia) discourse) is the study of the universe in its totality and by extension mans place in it. ... It has been suggested that Law of universal gravitation be merged into this article or section. ... Fig. ... Quantum gravity is the field of theoretical physics attempting to unify the theory of quantum mechanics, which describes three of the fundamental forces of nature, with general relativity, the theory of the fourth fundamental force: gravity. ...

Some scientists believe that the hypothesis is the result of a numerological coincidence, and in 1961, Robert Dicke argued that carbon-based life can only arise when the hypothesis is true lest fusion of hydrogen in stars not occur. A few proponents of non-standard cosmologies refer to Dirac's cosmology as a foundational basis for their ideas. Numerology is an arcane study of the purported mystical relationship between numbers and the character or action of physical objects and living things. ... 1961 was a common year starting on Sunday (link will take you to calendar). ... Robert Henry Dicke (May 6, 1916 – March 4, 1997) was an American physicist and astrophysicist. ... Life is a multi-faceted concept. ... The deuterium-tritium fusion reaction is considered the most promising for producing fusion power. ... General Name, Symbol, Number hydrogen, H, 1 Chemical series nonmetals Group, Period, Block 1, 1, s Appearance colorless Atomic mass 1. ... For alternate meanings see star (disambiguation) Hundreds of stars are visible in this image taken by the Hubble Space Telescope of the Sagittarius Star Cloud in the Milky Way Galaxy. ... A non-standard cosmology is a cosmological framework that contradicts the standard model of physical cosmology. ...

References

• Dirac, P. A. M. "The Cosmological Constants." Nature 139 (1937) 323.
• Dirac, P. A. M. "Cosmological Models and the Large Numbers Hypothesis." Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences, Vol. 338, No. 1615. (Jul. 16, 1974), pp. 439-446.

External links

• gr-qc/0111034 Guillermo A. Mena Marugan, Saulo Carneiro: Holography and the large number hypothesis
• The Mysterious Eddington-Dirac Number