Infinity Hotel
Infinity Hotel refers to Hilbert's paradox of the Grand Hotel, a thought experiment by mathematician David Hilbert that illustrates the counterintuitive nature of infinity. This pocket of imagination explores the ties between General Relativity and Hilbert's paradox and the ever wondering nature of Black Holes.
The name Infinity Hotel belongs to David Hilbert.
Pinched Space
Instead of a two dimensional sheet, four dimensional space-time can also be visualised as a three-dimensional volume that is narrowed or "pinched in" around large masses.
General Relativity at Work
Einstein encapsulated his theory of how mass distorts space-time in his set of field-equations. Physicists have used these equations to find that it is in the strongest gravitational fields - where massive dense objects distort space-time most strongly.
Before the introduction of general relativity, space and time were thought of only as an arena in which events took place. After general relativity, physicists realised that space and time are dynamic entities that can be affected by mass, forces, and energy. However, while general relativity accurately describes the Universe on a large scale, it has little to say about how it works at the tiniest, subatomic scale.
One of Einstein's major predictions based on general relativity was the existence of gravitational waves. These waves can be regarded as disturbances in the curvature of space-time that propagate outwards from their source - accelerated masses - at the speed of light. For over 100 years, gravitational waves remained hypothetical and unobserved, but in early 2016 it was announced that the first direct observation of such waves have been made, originating from a pair of merging black holes some 1.3 million light years from Earth.
Introduction
Named in honor of the trailblazing astronomer Edwin Hubble, the Hubble Space Telescope is a large, space-based observatory that has changed our understanding of the cosmos since its launch and deployment by the space shuttle Discovery in 1990.
Hubble’s capabilities have grown immensely in its over 30 years of operation. This is because new, cutting-edge scientific instruments have been added to the telescope over the course of five astronaut servicing missions. By replacing and upgrading aging parts, these servicing missions have greatly extended the telescope’s lifetime.
Telescopes have a particular range of light that they can detect. Hubble’s domain extends from the ultraviolet through the visible (which our eyes see) and into the near-infrared. This range has allowed Hubble to deliver stunning images of stars, galaxies, and other astronomical objects that have inspired people around the world.
Hubble has made more than 1.6 million observations over the course of its lifetime. Over 21,000 peer-reviewed science papers have been published on its discoveries, and every current astronomy textbook includes contributions from the observatory. The telescope has tracked interstellar objects as they soared through our solar system, watched a comet collide with Jupiter, and discovered moons around Pluto. It has found dusty disks and stellar nurseries throughout the Milky
Way that may one day become fully fledged planetary systems and studied the atmospheres of planets that orbit other stars. Hubble has peered back into our universe’s distant past, to locations more than 13.4 billion light-years from Earth, capturing galaxies merging, probing the supermassive black holes that lurk in their depths, and helping us better understand the history of the expanding universe.
In its over 30 years of operation, Hubble has made observations that have captured humanity’s imaginations and deepened our knowledge of the cosmos.
It will continue to do so for years to come.
warped space-time
object with large mass
White Dwarf
A white dwarf is a very dense, planet-sized star that can be thought of as producing a smaller, but deeper dent in space-time than does a star like the Sun.
Neutron Star
A neutron star is an exceedingly dense stellar remnant that makes a very deep dent in space-time. A neutron star significantly deflects light passing by, but cannot capture it.
Black Hole
In a black hole, all the mass is concentrated into an infinitely dense point at the centre, called singularity. A singularity produces an infinite distortion in space-time - a bottomless gravitational well. Any light that passes a boundary called "event horizon" near the entrance of this well cannot return
intense gravity
relatively weak gravity
event horizon, beyond which nothing, not even light, can break free of the gravitational field
extremely intense gravity
gravitational well of infinite depth, with steepness (gravity) increasing to infinity
singularity at the centre of the black hole
relatively weak
gravity
deep, steep
gravitational well
massive, dense neutron star
intense gravity
close to the star
white dwarf star
moderately steep
gravitational well
relatively weak gravity
Infinity Hotel
The Infinity Hotel refers to Hilbert's paradox of the Grand Hotel, a thought experiment by mathematician David Hilbert that illustrates the counterintuitive nature of infinity. The paradox describes a fully occupied hotel with infinitely many rooms, which can still accommodate any finite number of new guests by asking existing guests to move to a new room (ex.: guest in room n moves to room n+1). It can even accommodate an infinite number of new guests, such as those from an infinitely large bus, by asking current guests to move from room n to room 2n, freeing up all the odd-numbered rooms.