User:Floaterfluss/My projects/Orders of magnitude (time)

5.4 × 10⁻⁴⁴ s – the Planck time, the earliest time after the Big Bang that theoretical physics can describe.
0.3 yoctoseconds – mean life of the W and Z bosons.
1 ys, time for top quark decay
91 ys, half-life of lithium-4
7 zs, half-life of helium-9's outer neutron in the second nuclear halo
about 17 zs, the approximate period of electromagnetic radiation at the boundary between gamma rays and X-rays
about 300 zs, typical cycle time of X-rays, on the boundary between hard and soft X-rays
1 attosecond (1 as) – estimated time it takes for an atomic nucleus to recoil
about 100 attoseconds – record for shortest time interval measured as of February 2004 (BBC News)
about 200 attoseconds – half-life of beryllium-8, maximum time available for the triple-alpha process for the synthesis of carbon and heavier elements in stars.
250 attoseconds – the shortest pulses of laser light yet created (2002)
320 attoseconds – estimated time it takes electrons to hop between atoms
1.3 femtoseconds (fs) – cycle time for 390 nanometre light, transition from visible light to ultraviolet
2.57 femtoseconds – cycle time for 770 nanometre light, transition from visible light to near-infrared
100 femtoseconds – the time required to travel across a human hair, if travelling at the speed of light
200 femtoseconds – the swiftest chemical reactions, such as the reaction of pigments in an eye to light
300 femtoseconds – the duration of a vibration of the atoms in an iodine molecule
1 picosecond – half-life of a bottom quark
1.66 picoseconds – switching time of the world's fastest transistor (604 GHz, as of 2005) Article
3.3 picoseconds (approximately) – time taken for light to move 1 millimetre
10 picoseconds after the Big Bang – electromagnetism separates from the other fundamental forces
1.087827757 × 10⁻¹⁰ seconds – transition time between the two hyperfine levels of the ground state of the caesium-133 atom at zero kelvins
1.0 nanoseconds (1.0 ns) – cycle time for frequency 1 GHz, radio wavelength 0.3 m
1.02 nanoseconds (approximately) – time taken for light to travel 1 foot
3.3 nanoseconds (approximately) – the time it takes a common 3.0 GHz computer CPU to add two integers
3.33564095 nanoseconds (approximately) – time taken for light to travel 1 metre
10 nanoseconds (10 ns) – cycle time for frequency 100 MHz, radio wavelength 3 m (VHF, FM band)
10 nanoseconds – one shake, approximate time of one generation of a nuclear chain reaction with fast neutrons
12 nanoseconds – half-life of a K meson
20–40 nanoseconds – time of fusion reaction in a hydrogen bomb
0.1 microseconds (μs) – cycle time for frequency 10 MHz, radio wavelength 30 m (shortwave)
0.333 microseconds – cycle time of highest medium wave radio frequency, 3 MHz
0.500 microseconds – T1 time of Josephson phase qubit (see also Qubit) as of May 2005
1 microsecond (1 μs) – cycle time for frequency 1 MHz, radio wavelength 300 m (AM mediumwave band)
1 microsecond – the length of time of a high-speed, commercial strobe light flash
2 microseconds – the life time of a muonium particle
3.33564095 microseconds – the time taken by light to travel one kilometre in a vacuum
5.4 microseconds – the time taken by light to travel one mile in a vacuum
1 microsecond (1 μs) – cycle time for frequency 1 MHz, radio wavelength 300 m (AM mediumwave band)
1 microsecond – the length of time of a high-speed, commercial strobe light flash
2 microseconds – the life time of a muonium particle
3.33564095 microseconds – the time taken by light to travel one kilometre in a vacuum
5.4 microseconds – the time taken by light to travel one mile in a vacuum
0.1 milliseconds (0.1 ms) – cycle time for frequency 10 kHz
0.125 milliseconds – sampling interval for telephone audio (8000 samples/s)
0.24 milliseconds – half-life of ununbium 277
0.25 milliseconds – cycle time for highest tone in telephone audio (4 kHz)
1 millisecond (1 ms) – cycle time for frequency 1 kHz
1 millisecond – duration of light for typical photo flash strobe
1 millisecond – repetition interval of GPS C/A PN code
1.000692286 milliseconds – time taken for light to travel 300 km in a vacuum
2 milliseconds – half life of hassium-265
2.27 milliseconds – cycle time for the A above middle C in music (440 Hz); if a tuning device for musical instruments generates just one tone, it is probably this tone
3 milliseconds – a housefly’s wing flap
3.4 milliseconds – half life of meitnerium-266
5 milliseconds – a honeybee’s wing flap
8 milliseconds – camera shutter speed at setting 125
9 milliseconds – typical maximum seek time for a 7200rpm hard disk
10 milliseconds (10 ms) – cycle time for frequency 100 Hz (also known as a "jiffy")
16.7 milliseconds – cycle time for American 60 Hz AC mains grid
20 milliseconds – cycle time for European 50 Hz AC mains grid
33.3 milliseconds – the amount of time one frame lasts in 30fps video
50 milliseconds – cycle time for the lowest audible tone, 20 Hz
60 milliseconds – cycle time for European 16.7 Hz AC electrified railroad power grid
62.5 milliseconds - a sixty-fourth note at MM = 60
30 to 100 milliseconds – typical minimum latency for a broadband internet connection (important for online gaming)
100 milliseconds (100 ms) – the blink of an eye; see also human's periods
100 milliseconds – the reaction speed of a human
102 milliseconds – half-life of bohrium-262
125 milliseconds - a thirty-second note at MM = 60
134 milliseconds – time taken by light to travel around the earth's equator
150 milliseconds – recommended maximum time delay for telephone service
250 milliseconds – recommended maximum time delay for a computer terminal or web page
250 milliseconds is an approximate average of the round trip time for communications via geosynchronous satellites
250 milliseconds - a sixteenth note at MM = 60
200 to 670 milliseconds – a beat of modern dance music
400 milliseconds - time in which the fastest baseball pitches reach the strike zone
500 milliseconds - an eighth note at MM = 60
838 milliseconds – half-life of lithium-8
100 milliseconds (100 ms) – the blink of an eye; see also human's periods
100 milliseconds – the reaction speed of a human
102 milliseconds – half-life of bohrium-262
125 milliseconds - a thirty-second note at MM = 60
134 milliseconds – time taken by light to travel around the earth's equator
150 milliseconds – recommended maximum time delay for telephone service
250 milliseconds – recommended maximum time delay for a computer terminal or web page
250 milliseconds is an approximate average of the round trip time for communications via geosynchronous satellites
250 milliseconds - a sixteenth note at MM = 60
200 to 670 milliseconds – a beat of modern dance music
400 milliseconds - time in which the fastest baseball pitches reach the strike zone
500 milliseconds - an eighth note at MM = 60
838 milliseconds – half-life of lithium-8
27 seconds – half life of dubnium-261
30 seconds – half life of seaborgium-266
30 seconds – half life of ununquadium-289
30 seconds – most common length of a TV commercial in the USA
32.184 seconds – the amount that Terrestrial Time precedes International Atomic Time
34 seconds – half life of dubnium-262
60 seconds = one minute
61 seconds – half life of rutherfordium-261
86.4 seconds = 1 minute 26.4 seconds = 10^-3 days – the length of a Swatch ".beat"
100 seconds = 1 minute 40 seconds
100 seconds – 1 minute 40 seconds, or 1.666... minutes
102 seconds – half-life of nobelium-253
102 seconds – duration of the Minute Waltz of Frédéric Chopin, as recorded by Dinu Lipatti
180 seconds = 3 minutes – approximate time for cooking instant noodles or for boiling an egg
273 seconds – nominal duration of 4'33 by John Cage
315 seconds = 5.25 minutes (approximately 10^-5 years) after the Big Bang – first nuclei form
500 seconds = 8.333... minutes – approximate time it takes light to travel between earth and the sun
660 seconds = 11 minutes – duration of a 1000-foot reel of 35mm motion picture film
886 seconds (approximately 14.8 minutes) – half-life of a free neutron
930 seconds (approximately 15.5 minutes), may vary by performance, duration of the Brandenburg Concerto #4 by Johann Sebastian Bach
1000 seconds – approximately 16.7 minutes
1892 seconds = 31'32" - duration of Igor Stravinsky's ballet score Le Sacre du printemps (composer's 1960 recording).
2700 seconds = 45 minutes – the length of the Anglo-Zanzibar War, the shortest war in history
2926 seconds = 48 minutes 46 seconds – the change in time of moon rise from one day to the next
3000 seconds (approximately): duration of Johannes Brahms' second piano concerto
3320 seconds = 56 minutes - duration of the collapse of World Trade Center #2 (South Tower) on September 11, 2001
3480 seconds = 58 minutes – half-life of nobelium-259
3600 seconds = 60 minutes = one hour
4440 seconds = 74 minutes – the originally specified maximum length of audio that can be stored on a 120-mm compact disc
5400 seconds = 90 minutes – the time needed for an object in low earth orbit to circle the earth
5700 seconds = 95 minutes – length of Gustav Mahler's Third Symphony, the longest symphony in the repertory of classical music
7140 seconds = 119 minutes – runtime of the film Citizen Kane
10,379 seconds = 2 hours 52 minutes 59 seconds = the length of the record New York–London Concorde flight
19,872 seconds = 5.52 hours – half-life of mendelevium-257
25,200 seconds = 7 hours – one work day in France.
28,800 seconds = 8 hours – one work day in many Western countries
28,800 seconds = 8 hours – common human daily need for sleep
36,000 seconds = 10 hours – one work day in ancient Egypt, according to the oldest definition of an hour
37,296 seconds = 10.36 hours – half-life of erbium-165
54,000 seconds = 15 hours – approximate length of Wagner's opera cycle Der Ring des Nibelungen
72,606 seconds = 20 hours 10 minutes 6 seconds – the world record of human standing motionlessly as of 2005 [1]
80,100 seconds = 22.25 hours – approximate time taken to solve the DES Challenge III of RSA on January 18 - 19, 1999 [2]
86,164 seconds = 23 hours 56 minutes 4 seconds – time for Earth’s rotation around its axis
86,400 seconds = 24 hours = one day
91,404 seconds = 25.39 hours – half-life of fermium-252
102,888 seconds = 28.58 hours – half life of erbium-160
259,200 seconds = 3 days – half-life of fermium-253
432,000 seconds = 5 days – one work week
483,062.4 seconds = 5.591 days – half life of manganese-52
604,800 seconds = 7 days = one week
799,200 seconds = 9.25 days – half life of thulium-167
864,000 seconds = 10 days – length of a new week (décade) in the French Revolutionary Calendar
1.21×10⁶ seconds = 14 days – a fortnight
1.38×10⁶ seconds = 15.9735 days – half life of vanadium-48
1.54×10⁶ seconds = 17.81 days – half life of californium-253
2.36×10⁶ seconds = 27.3217 days – sidereal month
2.39×10⁶ seconds = 27.7025 days – half life of chromium-51
2.42×10⁶ seconds = 28 days – length of February in non-leap years
2.51×10⁶ seconds = 29 days – length of February in a leap year
2.55×10⁶ seconds = 29.53059 days – mean synodic month
2.59×10⁶ seconds = 30 days – length of the months April, June, September, and November
2.68×10⁶ seconds = 31 days – length of the months January, March, May, July, August, October, and December
4.45×10⁶ seconds = 51.5 days – half life of mendelevium-258
5.23×10⁶ seconds = 60.5 days – half life of californium-254
6.68×10⁶ seconds = 77.27 days – half life of cobalt-56
7.24×10⁶ seconds = 83.79 days – half life of scandium-46
7.54×10⁶ seconds = 87.32 days – half life of sulfur-35
7.60×10⁶ seconds = 87 days 23.3 hours – one orbit of Mercury
7.78×10⁶ seconds = 90 days – common length of a product warranty (in the United States)
7.78×10⁶ seconds = 90 days – approximate length of a quarter year, a common corporate and financial reporting interval
8.04×10⁶ seconds = 93.1 days – half life of thulium-168
8.68×10⁶ seconds = 100.5 days – half life of fermium-257
10 megaseconds = 115.74 days
128.6 days — half life of thulium-170
138 days — half life of polonium- 210
224.701 days — one orbit of Venus
271.79 days — half life of cobalt-57
280 days — average length of a human pregnancy; ~24 million seconds
330 days — half life of vanadium-49
333.5 days — half life of californium-248
353, 354 or 355 days — the lengths of regular years in some lunisolar calendars
354.37 days — 12 lunar months; the average length of a year in lunar calendars
365 days — a regular year in many solar calendars; ~31.53 million seconds
365.24219 days — a mean tropical year near the year 2000
365.2424 days — a vernal equinox year.
365.2425 days — the average length of a year in the Gregorian calendar
365.25 days — the average length of a year in the Julian calendar
365.2564 days — a sidereal year
366 days — a leap year in many solar calendars; 31.62 million seconds
373.59 days — half-life of ruthenium-106
383, 384 or 385 days — the lengths of leap years in some lunisolar calendars
383.9 days — 13 lunar months; leap year in some lunisolar calendars
396.1 days — half-life of neptunium-235
462.6 days — half-life of cadmium-109
1.88 years — one orbit of Mars
1.92 years — half life of thulium-171
100 megaseconds = 3.2 years
3.3 years – half life of rhodium-101
4 years – full term of the President of the United States
4.6 years – orbital period of Ceres
5.2714 years – half life of cobalt-60
6 years – full term of a Senator in the United States
7 years – the interval between leap seconds on December 31, 1998 and December 31, 2005, the longest one as of 2006
10 years – one decade = 3.16 × 10⁸ seconds
11 years – sunspot activity cycle (7.5 to 11 years)
11.87 years – one orbit of Jupiter
13.08 years – half life of californium-250
16.13 years – half life of niobium meta state Nb-93m
18.03 years – Saros cycle, the period of solar eclipses and lunar eclipses
19.0002 years – 235 months (1 Metonic cycle)
29 years – recorded maximum lifespan of a dog
29.1 years – half life of curium-243
29.458 years – one orbit of Saturn
35 years – Constitutionally-mandated minimum age for President of the United States.
50.5 years – average age of human menopause
60 years – duration of Indian independence as of 2007
63 years – half-life of titanium-44
65 years – a common age for retirement of workers
68.9 years – half-life of uranium-232
72 years, 3 months, 18 days: reign of Louis XIV
75 years – average life span of humans in the First World
78 years – estimated maximum lifespan of an elephant
84 years, 3 days, 15.66 hours – one orbit of Uranus
100 years – one century = 3.16 × 10⁹ seconds
100.1 years – half-life of nickel-63
122 years and 164 days – longest recorded lifespan of any known human (Jeanne Calment)
130 years – approximate age of the telephone, recorded music, and the electric light
165 years – one orbit of Neptune
190 years – credited age of the oldest known tortoise, oldest land animal
231 years – age of the United States of America as of 2007
247.7 years – one orbit of Pluto
269 years – half-life of argon-39
288 years – one orbit of Quaoar
292 years – age of the ruling Hanoverian dynasty (1714) in Great Britain as of 2006
302 years – duration of Spanish colonial rule in Mexico
304 years – duration of the Romanov dynasty in Russia
351 years – half-life of californium-249
377 years – age (in 2007) of the Massachussetts General Court, oldest continuous extant elected assembly
403 years – duration of the Hohenzollern monarchy in Brandenburg, Prussia, and Germany
418 years – half life of silver-108
432.2 years – half life of americium-241
507 years – duration of the Roman Empire
515 years – time since Christopher Columbus reached the New World
555 years – oldest surviving printing by movable type
680 years – half life of niobium-91
685 years (approximately) – age of Dante Aligheri's Divine Comedy
790 years – approximate duration of Zhou Dynasty (c.1046 BC - 256 BC), the longest dynasty in Chinese history.
898 years – half life of californium-251
1000 years – one millennium = 3.16 x 10¹⁰ seconds*
1053 years – duration of the Byzantine Empire
1140 years – age of Varangian settlements and influence in Russia
1427 years – time since the Hegira
1550 years (approximately) – time since the Anglo-Saxon invasion of Britain
1927 years – time since the volcanic destruction of Pompeii (79AD)
2439 years – age of the Parthenon as a completed building (432 BC)
2500 years (approximately) age of Euclid's Elements
2782 years – time since the legendary founding of Rome (776 BC)
3,200 years – time since the Greek Dark Ages and the beginning of the Iron Age
3,800 years – time since alphabetic writing emerged
4,500 years – approximate time since the domestication of the horse
4,700 years – estimated age of oldest living plant, a bristle-cone pine
5,300 years – time since Sumerians developed cuneiform writing
5,400 years – time since Neolithic Age ended and Bronze Age began
5,715 years – half-life of Carbon-14
6,010 years – age of the earth according to the calculation of Bishop Ussher (in 2006)
6,500 years [3500 in the Dutch version of Wikipedia] – time since the invention of the wheel
7,370 years – half life of americium-243
8,500 years – half life of curium-245
10,000 years – time since city of Jericho was founded
10,000 years – time since end of Pleistocene Epoch
10,000 years – time since beginning of Holocene Epoch
12,000 years – time since beginning of Neolithic Age
12,000 years – time since the land ice left Denmark and southern Sweden
20,000 years – approximate age of the Ishango Bone, the oldest known tally stick
20,300 years – half life of niobium-94
21,000 years – time since the Last Glacial Maximum
24,110 years – half life of plutonium-239
25,000 years – time since the first colonisation of North America
30,000 years – approximate age of Haplogroup X (mtDNA) and Haplogroup I (mtDNA)
40 000 years – time since the Cro-Magnon colonisation of Europe (Upper Paleolithic)
50 000 years – age of Haplogroup B (mtDNA)
60 000 years – approximate age of Haplogroup N (mtDNA), Haplogroup C (mtDNA) and Haplogroup A (mtDNA); out of Africa migration.
75 000 years – time since the ancestors of the Indigenous Australians reached Australia
76 000 years – half-life of nickel-59
80 000 years – approximate age of Haplogroup M (mtDNA)
90 000 years – approximate age of Y-chromosomal Adam
100 000 years – earliest estimate for the domestication of dogs
150 000 years – approximate age of mitochondrial Eve
154 000 years – half-life of neptunium-236
159 200 years – half-life of uranium-233
160 000 years – time since the Homo sapiens idaltu/Homo sapiens sapiens split
200 000 years – approximate age of Homo sapiens
211 100 years – half-life of technetium-99
250 000 years – approximate age of Homo neanderthalensis
300 000 years – time since Homo sapiens separated from Homo erectus (Middle Paleolithic)
301,000 years – half-life of chlorine-36
340,000 years – half-life of curium-248
379 000 years – time after the Big Bang until cosmic microwave background radiation began
500 000 years – time since the colonisation of Eurasia by Homo erectus
~700,000 years – time since last reversal of earth's magnetic field
790 000 years – age of the earliest evidence of the controlled use of fire by Homo erectus
1,000,000 years – the average lifespan of a blue supergiant star
1,500,000 years – time since beginning of Pleistocene Epoch (beginning of Quaternary Period)
1,500,000 years – time since end of Pliocene Epoch (end of Tertiary Period)
1,530,000 years – half-life of zirconium-93
2,000,000 years – duration of the Paleolithic
2,500,000 years – approximate age of the genus Homo
2,600,000 years – half-life of technetium-97
3.74 million years – half-life of manganese-53
4 million years – estimated average lifetime of biological species
4 million years – time since beginning of last ice age
4.2 million years – half-life of technetium-98
4.5 million years – approximate age of the genus Australopithecus
5 million years – time since beginning of Pliocene Epoch
5 million years – time since end of Miocene
5.5 million years – approximate age of the genus Ardipithecus
5-7 million years – estimated age of the Pan/Homo split
6.5 million years – half-life of palladium-107
15.6 million years – half-life of curium-247
18-12 million years – estimated age of the Hominidae family
20 million years – time since the first forms of grass appeared
23.42 million years – half-life of uranium-236
24 million years – time since beginning of Miocene Epoch
24 million years – time since end of Oligocene Epoch
34.7 million years – half-life of niobium-92
36 million years – time since end of Eocene Epoch and beginning of Oligocene Epoch; age of the Cercopithecidae (Old World primates) superfamily.
40 million years – estimated period of time until Australia will collide with Asia; time since the age of the Catarrhini parvorder.
65 million years – time since Cretaceous-Tertiary extinction event at end of Cretaceous Period (end of Mesozoic Era) and beginning of Tertiary Period (beginning of Cenozoic Era); age of the Haplorrhini suborder.
135 million years – time since end of Jurassic and beginning of Cretaceous Period.
195 million years – time since end of Triassic and beginning of Jurassic Period; time since the appearance of the earliest mammals.
225 million years – time since end of Permian Period (end of Palaeozoic Era) and beginning of Triassic Period (beginning of Mesozoic Era).
250 million years – Galactic year - a revolution around the center of the Milky way of our Sun and the Solar system.
280 million years – time since end of Carboniferous and beginning of Permian Period.
340 million years—time since the beginning of the Carboniferous and the end of Devonian period
400 million years—time since the beginning of the Devonian and the end of the Silurian period
420 million years—time since the first creature took a breath of air
435 million years—time since the beginning of the Silurian and the end of the Ordovician period
500 million years—time since the beginning of the Ordovician and the end of the Cambrian period
540 million years—time since the beginning of the Cambrian and the end of the Precambrian period. Time since the Cambrian explosion and age of the earliest Vertebrates.
575 million years— age of the oldest Animal fossils
580 million years—time since the end of a possible Snowball Earth ice age
600 million years—age of first complex multicelled lifeforms
703.8 million years—half-life of uranium-235
750 million years—time since the beginning of a possible Snowball Earth ice age
1277 million years—half-life of potassium-40
1.8-2.1 billion years—age of the earliest Eukaryotes
2.3 billion years—time since the first known ice age
3.0 billion years—time until the potential collision between the Milky Way and Andromeda galaxies
3.5 billion years — age of oldest cellular life (Prokaryotes)
3.7 to 3.9 billion (3.7e9 to 3.9e9) years — age of the Mare Imbrium, the Lower Imbrian epoch
4.468 billion years — half-life of uranium-238
4.5 billion years — age of the Earth (see: Precambrian)
10 billion years — expected main sequence lifetime of a G2 dwarf star (like the Sun)
13.7 ± 0.2 billion years (4e17 seconds) — estimated age of the universe according to the Big Bang theory
20 billion years — time until the end of the universe in the Big Rip scenario
100 billion (10¹¹) years – If the Universe is closed, the estimated total lifetime of the Universe
3.3 × 10¹² years – According to the traditional Vedic time of Hinduism, this is the lifetime of Brahma.

Some radioisotopes have extremely long half-lives:

(1.4 ± 0.4) × 10¹⁷ years – vanadium-50
(1.9 ± 0.2) × 10¹⁹ years – bismuth-209
(3.1 ± 0.4) × 10¹⁹ years – cadmium-116
(2.2 ± 0.3) × 10²⁴ years – tellurium-128

The following times all assume that the Universe is "open":

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 the 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)
$10^{10^{26}}$ years – low estimate for the time until all matter collapses into black holes, assuming no proton decay
$10^{10^{76}}$ 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. 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.

$10^{10^{10^{10^{10^{1.1}}}}}$ 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.

^ Adams, Fred C.; Kane, Gordon L.; Mbonye, Manasse; Perry, Malcolm J. (2000). "Proton Decay, Black Holes, and Large Extra Dimensions" (Document). Int.J.Mod.Phys. A16 (2001) 2399-2410. {{cite document}}: Cite has empty unknown parameter: |version= (help); Italic or bold markup not allowed in: |publisher= (help); Unknown parameter |accessdate= ignored (help); Unknown parameter |url= ignored (help)CS1 maint: multiple names: authors list (link)

[Adams-1] Adams, Fred C.; Kane, Gordon L.; Mbonye, Manasse; Perry, Malcolm J. (2000). "Proton Decay, Black Holes, and Large Extra Dimensions" (Document). Int.J.Mod.Phys. A16 (2001) 2399-2410. {{cite document}}: Cite has empty unknown parameter: |version= (help); Italic or bold markup not allowed in: |publisher= (help); Unknown parameter |accessdate= ignored (help); Unknown parameter |url= ignored (help)CS1 maint: multiple names: authors list (link)

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