The universe (if it were stable for all this time—and we have no reason to believe it is—and infinite in spatial dimension—and it very well could be) is old enough to have a 50% chance of light reaching us from an object completely identical to our universe. This is a consequence of an intuition already present in Friedrich Nietzsche’s mind: nothing is unique, everything has an unlimited number of copies, anything with a probability greater than zero of happening must happen infinitely many times.

The universe (if it were stable for all this time—and we have no reason to believe it is—and infinite in spatial dimension—and it very well could be) is old enough to have a 50% chance of light reaching us from an object completely identical to our Earth. This is a consequence of an intuition already present in Friedrich Nietzsche’s mind: nothing is unique, everything has an unlimited number of copies, anything with a probability greater than zero of happening must happen infinitely many times.

The universe (if it were stable for all this time—and we have no reason to believe it is—and infinite in spatial dimension—and it very well could be) is old enough to have a 50% chance of the light of a living being entirely similar to us reaching us. This is a consequence of an intuition already present in Friedrich Nietzsche’s mind: nothing is unique, everyone possesses an unlimited number of copies, and anything with a probability greater than zero of happening must happen infinitely many times.

Even enormous galactic black holes with original masses equal to several billion solar masses, such as the one that lay at the center of Milkomeda, the galaxy born from the merger of (our) Milky Way and Andromeda, evaporate.

Even galactic black holes with original masses of several million solar masses evaporate.

The first large black holes evaporate

The decay of protons lowers the atomic number of atoms in the Universe: even white dwarfs (re)transform into hydrogen.

The decay of protons lowers the atomic number of atoms in the Universe: the metallic nuclei of the remaining rocky planets are transformed into hydrogen.

Stellar fuel runs out

Black Holes Finish Devouring Galaxies

Bismuth half-life: 50% of bismuth decays. Bismuth will be the last element to disappear.

Galaxies gradually evaporate due to the gravitational slingshot effect caused by random close encounters between stars.

Red dwarfs become black dwarfs, veritable stellar corpses.

Star formation ceases

The electromagnetic radiation of stars is stretched by the accelerated expansion (by dark energy) of the Universe and the wavelength of photons becomes longer than that of the visible Universe.

Other galaxies become invisible due to the redshift

Due to the redshift, the gigantic Virgo Cluster falls beyond our visible horizon and Milkomeda remains the only observable galaxy.

The Universe is 1000 times larger than it is today

In the theory conceived in 2003 by Robert Caldwell, the strength of dark energy grows so dramatically that it soon disintegrates matter itself until the Big Rip in 20 billion years. The theory is not widely accepted in the scientific community.

The Sun’s core runs out of helium. Gravity takes over and causes a new collapse of the core, triggering violent and unstable fusions. A series of four convulsions occurs, each separated by 100,000 years. The Sun reaches a terrifying luminosity of 5,200 times its current brightness. These are the death rattles of our star. The outer layers, now expelled beyond the inner planetary system, are repeatedly illuminated. The Sun is on its way to becoming a white dwarf, gradually dissipating its remaining heat into space.

The Sun’s core compresses and heats up to 100 million degrees. The heat expands to the outer layers, transforming it into a bloated red giant 250 times larger and 2,700 times brighter than today. The Earth reaches the solar atmosphere, and soon the friction causes it to fall onto the Sun, literally “cremating” it. The end of planet Earth.

The Sun’s hydrogen shell ignites and our star grows to twice its current size.

Second collision between the Milky Way and Andromeda. At this point, the two galaxies are an ellipsoidal cluster of nearly 1 trillion stars: an elliptical galaxy that T.J. Cox and Abi Loeb of the Harvard-Smithsonian Center for Astrophysics call Milkomeda.

The Sun (and the Solar System), if the Milky Way did not collide with Andromeda, would leave the Orion Arm and enter the Perseus Arm, towards the Galactic Center.

The Milky Way’s central black hole grows from a few million to a few billion solar masses thanks to a glut of stars triggered by the instability caused by the initial impact with Andromeda. Eventually, the object cyclically transforms into a very bright quasar for 10 million years, alternating with periods of quiet lasting about 100 million years.

In the merger of our Galaxy (the Milky Way) and that of Andromeda, the Sun has a 12% chance of ending up in the tidal tail and being ejected into the depths of intergalactic space, a 3% chance of being engulfed by Andromeda in subsequent rebounds until complete fusion into Milkomeda, a 40% chance of ending up in the core of the galaxy, and a 45% chance of being hurled into the outer halo.

The Milky Way and Andromeda Galaxy collide for the first time. Gravity creates rings and ripples in the stellar distribution, expelling a gigantic arc containing more than a billion stars into the intergalactic void.

The Sun completes its next orbit around the galactic center

Approximate estimated time of the disappearance of Saturn’s rings, inexorably attracted to the planet and crashing into it.

Next passage of the Great Comet of January 1910. In 1910 it was very bright, visible even to the naked eye and during the day.

Comets launched into the inner Solar System by the passage of the Scholz binary star are hurtling around the Sun, threatening even Earth. The Scholz binary star was discovered in 2013 AD and is composed of a red dwarf and a brown dwarf, both very faint in luminosity and mass. The Scholz binary passed in 68,000 BC within just 52,000 AU (Astronomical Units = Earth-Sun distance) of the Sun (0.8 light-years). They therefore undoubtedly interacted with the outer layers of the Oort Cloud, a repository of dormant comets, launching a certain number (perhaps several million) on the long journey (a couple of million years!) into the inner Solar System, while others may have been captured and still others ejected into interstellar space or even ultimately into extragalactic space.

The red dwarf star Gliese 710 passes just 1 light-year from the Sun, interfering with the Oort Cloud and launching several million comets toward the inner Solar System and thus Earth. At this point, Gliese 710 shines in the sky with a magnitude equivalent to a star in Orion’s Belt today. The long journey to the inner Solar System will take a couple of million years.

850 light-years away, the (now) blue supergiant Rigel, in the constellation of Orion, explodes in a spectacular type II supernova, lighting up Earth’s night sky like 100 full moons concentrated in one spot. Before Rigel, Orion’s other very bright star, Betelgeuse (620 light-years away), may have already exploded in a type II supernova, but given its current instability, it’s difficult to determine how long it will take (thousands or millions of years).

Two symbols of human greatness will disappear: the pyramids of Giza and the astronauts’ footprints on the Moon.

(current age of the Universe) The universe, considered with discrete time and matter with discrete quantum structure and discrete states, that is, considered as a gigantic computer that processes information (qubits), has processed since the Big Bang about 10^123 binary operations in the available 4E17s, contains 10^72 joules of energy (the link between energy and clock time expressed by the Margolus-Levitin theorem t>=h/4E) and 10^92 bits of ordinary matter (however no more than 10^123 bits of dark matter), memory considered as Entropy = Energy / Temperature = Temperature ^ 3 because when the entropy is maximum, that is, I have to encode the position and velocity of each particle to describe the state, I use all the available “memory”

The neutron star (100 trillion times denser than steel) born from the explosion of the supernova RX J185635-3754 passes (at 100 km/s) 170 light years from Earth

The constellations will have become unrecognizable due to the proper motions of the individual stars. By then, Betelgeuse will have exploded as a supernova.

Comet Hyakutake’s next pass. It previously passed near Earth in 1996.

We may receive a response to the Arecibo message.

The star Ross 248 will take away Proxima Centauri’s title as the closest star to the Sun.

The radio signal sent by Frank Drake from Arecibo reaches the globular cluster M13, composed of 300,000 stars

The seasons in the Northern and Southern Hemispheres are reversed compared to today, due to the precession of the equinoxes.

Passage of Flaugergues’ Comet, also mentioned by Tolstoy in “War and Peace.” It passed in 1811. It is expected to pass again in the year 4800.

Comet Hale-Bopp passes close to Earth. It passed in 1997 (I saw it).

Pluto completes its first “year” (revolution around the Sun) since it was discovered.

The signal sent by Yvan Dutil and Stephane Dumas, funded by the Houston-based company Encounter 2001 LLC, with the Evpatoria radio telescope in Ukraine, reaches 4 solar-type stars.

Halley’s Comet passes by Earth for the first time in 75 years. Keep the evening free in your calendars!