To help compare orders of magnitude of different times, this page lists times longer than 10¹⁹ seconds (317 billion years) See also times of other orders of magnitude. 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. ... Look up second in Wiktionary, the free dictionary. ... The pages linked in the right-hand column contain lists of times that are of the same order of magnitude (power of ten). ...

See the article about the ultimate fate of the Universe for more discussion of these issues. The ultimate fate of our universe is a topic in physical cosmology. ...

• Shorter times
• 2.0 × 10¹⁰ years – the end of the universe by the Big Rip
• 3.3 × 10¹² years – According to the traditional Vedic time of Hinduism, this is the lifetime of Brahma.
• 7.7 × 10¹⁵ years – half-life of cadmium-113
• 1.4 × 10¹⁷ years – half-life of vanadium-50
• > 1.8 × 10¹⁷ years – half life of chromium-50
• > 6 × 10¹⁸ years – half life of calcium-48
• (1.9 ± 0.2) × 10¹⁹ years – alpha emission half-life of bismuth-209
• 3.1 × 10²² years – estimated half-life of iron-54

The following times all assume that the Universe is "open": To help compare orders of magnitude of different times this page lists times between 1018 seconds (also known as an exasecond) and 1019 seconds (32 000 million years and 320 000 million years) See also times of other orders of magnitude. ... The Big Rip is a cosmological hypothesis about the ultimate fate of the Universe, in which the elements of the universe, from galaxies to atoms, are progressively torn apart by the expansion of the universe. ... {{Hinduism small} Hinduism (Sanskrit/Devanagari: , , also known as , ) is a religion that originated on the Indian subcontinent. ... Brahma (written Brahmā in IAST) (Devanagari ब्रह्मा, pronounced as ) is the Hindu God (deva) of creation, and one of the Hindu Trinity - Trimurti, the others being Vishnu and Shiva. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... General Name, Symbol, Number cadmium, Cd, 48 Chemical series transition metals Group, Period, Block 12, 5, d Appearance silvery gray metallic Atomic mass 112. ... General Name, Symbol, Number vanadium, V, 23 Chemical series transition metals Group, Period, Block 5, 4, d Appearance silver-grey metal Atomic mass 50. ... General Name, Symbol, Number chromium, Cr, 24 Chemical series transition metals Group, Period, Block 6, 4, d Appearance silvery metallic Atomic mass 51. ... General Name, Symbol, Number calcium, Ca, 20 Chemical series alkaline earth metals Group, Period, Block 2, 4, s Appearance silvery white Atomic mass 40. ... Alpha decay is a form of radioactive decay in which an atomic nucleus ejects an alpha particle and transforms into a nucleus with mass number 4 less and atomic number 2 less. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ... General Name, Symbol, Number bismuth, Bi, 83 Chemical series poor metals Group, Period, Block 15, 6, p Appearance lustrous reddish white Atomic mass 208. ... General Name, Symbol, Number iron, Fe, 26 Chemical series transition metals Group, Period, Block 8, 4, d Appearance lustrous metallic with a grayish tinge Atomic mass 55. ... The deepest visible-light image of the cosmos, the Hubble Ultra Deep Field. ... The Open universe theory is a theory in cosmology according to which the universe will continue to expand indefinitely. ...

• 10¹⁴ years – the estimated time until low-mass stars cool off. The smallest red dwarf stars are the longest-lived stars, and are believed to have a lifetime of up to 14 trillion years (1.4 x 10¹³ years). Star formation is expected to cease in galaxies in about 10¹³ to 10¹⁴ years as galaxies are depleted of the gas clouds they need to form stars. The longest-lived stars formed from the last gas clouds will therefore cool off after about 2 x 10¹⁴ years.
• 10¹⁵ years – the estimated time until planets detach from stars. Whenever two stars pass close to each other, the orbits of the planets can be disrupted and the planets can be ejected from orbit around their parent star. Planets that orbit closer to their stars take longer to be ejected in this manner on average because a passing star must make a closer pass to the planet's star to eject the planet.
• 10¹⁹ years – the estimated time until stars detach from galaxies. When two stars pass close enough to each other, the stars exchange orbital energy with lower-mass stars tending to gain energy. The lower-mass stars can gain enough energy in this manner through repeated encounters to be ejected from the galaxy. This process can cause the galaxy to eject the majority of its stars.
• 10²⁰ years – the estimated time until orbits decay by gravitational radiation
• 10³⁰ years – the estimated time until galaxies disappear due to black holes
• 10³⁶ years – the estimated half-life for proton decay, if GUT is right
• 10⁴⁰ years – the estimated expiration of all protons in the universe due to proton decay, if GUT is right (probability dictates only less than one proton in the universe will survive its half-life if its true value is close to our theoretical lower bound)
• 10⁴⁵ years – the estimated half-life of theorized radioactive decay of protons by virtual black holes, if they exist ^[1]
• 10⁶⁴ years – the estimated time until black holes decay by the Hawking process
• 10⁶⁵ years – the estimated timescale at which all matter is liquid at zero temperature due to tunneling effects
• 10¹⁰⁰ years (a googol year) – the estimated time until supermassive black holes decay by the Hawking process
• 10¹⁵⁰⁰ years – the estimated time until all matter decays to iron (if the proton does not decay)

An alternative could be the following also according to Dyson Freeman's "Time without end: physics and biology in an open universe" To meet Wikipedias quality standards, this article or section may require cleanup. ... A black hole is an object predicted by general relativity[1] with a gravitational field so strong that nothing can escape it — not even light. ... The decay of a proton, a baryon, into non-baryonic matter, does not occur perturbatively in the Standard Model. ... For the Physics term GUT, please refer to Grand unification theory The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and... The decay of a proton, a baryon, into non-baryonic matter, does not occur perturbatively in the Standard Model. ... For the Physics term GUT, please refer to Grand unification theory The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and... The decay of a proton, a baryon, into non-baryonic matter, does not occur perturbatively in the Standard Model. ... In physics, a virtual particle is a particle-like abstraction used in some models of quantum field theory. ... A black hole is an object predicted by general relativity[1] with a gravitational field so strong that nothing can escape it — not even light. ... In physics, Hawking radiation is thermal radiation emitted by black holes due to quantum effects. ... In quantum mechanics, the tunneling effect refers to various processes whereby particles appear to violate classical physics by instantaneously changing their location within the space-time continuum without passing observably through the intervening space. ... Look up googol in Wiktionary, the free dictionary. ... Supermassive Black Hole is a song by English rock band Muse and is featured on their 2006 album, Black Holes and Revelations. ... General Name, Symbol, Number iron, Fe, 26 Chemical series transition metals Group, Period, Block 8, 4, d Appearance lustrous metallic with a grayish tinge Atomic mass 55. ... The decay of a proton, a baryon, into non-baryonic matter, does not occur perturbatively in the Standard Model. ...

• 10^{100,000,000,000,000,000,000,000,000} years () – low estimate for the time until all matter collapses into black holes, assuming no proton decay
• 10^{10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000} years () – high estimate for the time until all matter collapses into neutron stars or black holes, again assuming no proton decay. Dyson Freeman, Reviews of Modern Physics, Vol. 51, No. 3, July 1979(c) 1979 American Physical Society

This time assumes a statistical model subject to Poincaré recurrence and is likely the longest finite time ever explicitly calculated by a physicist. A much simplified way of thinking about this time is in a model where our universe's history repeats itself arbitrarily many times due to properties of statistical mechanics, this is the time scale when it will first be somewhat similar (for a reasonable choice of "similar") to its current state again. A black hole is an object predicted by general relativity[1] with a gravitational field so strong that nothing can escape it — not even light. ... The decay of a proton, a baryon, into non-baryonic matter, does not occur perturbatively in the Standard Model. ... The decay of a proton, a baryon, into non-baryonic matter, does not occur perturbatively in the Standard Model. ... The Poincaré recurrence theorem states that a system having a finite amount of energy and confined to a finite spatial volume will, after a sufficiently long time, return to an arbitrarily small neighborhood of its initial state. ... Loschmidts paradox states that if there is a motion of a system that leads to a steady decrease of H (increase of entropy) with time, then there is certainly another allowed state of motion of the system, found by time reversal, in which H must increase. ... In physics and thermodynamics, the ergodic hypothesis says that, over long periods of time, the time spent in some region of the phase space of microstates with the same energy is proportional to the volume of this region, i. ...

• years – scale of an estimated Poincaré recurrence time for the quantum state of a hypothetical box containing a black hole with the estimated mass of our entire universe.

The Poincaré recurrence theorem states that a system having a finite amount of energy and confined to a finite spatial volume will, after a sufficiently long time, return to an arbitrarily small neighborhood of its initial state. ...

References

1. ^ Adams, Fred C.; Kane, Gordon L.; Mbonye, Manasse; Perry, Malcolm J. (2000). "Proton Decay, Black Holes, and Large Extra Dimensions" (PDF). Int.J.Mod.Phys. A16 (2001) 2399-2410. Retrieved on 2006-12-27.

PDF is an abbreviation with several meanings: Portable Document Format Post-doctoral fellowship Probability density function There also is an electronic design automation company named PDF Solutions. ... 2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ... December 27 is the 361st day of the year in the Gregorian Calendar (362nd in leap years). ...

External links

• [1] Dyson Freeman, Reviews of Modern Physics, Vol. 51, No. 3, July 1979(c) 1979 American Physical Society
• [2] Poincaré recurrence and large numbers