The second law of thermodynamics states that disorder, or entropy, tends to increase in any isolated system. For example, a box with a divide in the middle could have oxygen on one side and nitrogen on the other. It is in an ordered state. If the divide is removed, however, the particles will tend to mix and occupy both sides of the box, a disordered state with higher entropy. This is not a definite outcome, but according to the laws of thermodynamics is overwhelmingly likely.
Entropy Quotes in A Brief History of Time
The A Brief History of Time quotes below are all either spoken by Entropy or refer to Entropy. For each quote, you can also see the other terms and themes related to it (each theme is indicated by its own dot and icon, like this one: Note: all page numbers and citation info for the quotes below refer to the Bantam edition of A Brief History of Time published in 1988.).
Chapter 9 Quotes
The progress of the human race in understanding the universe has established a small corner of order in an increasingly disordered universe.
Entropy Term Timeline in A Brief History of Time
The timeline below shows where the term Entropy appears in A Brief History of Time. The colored dots and icons indicate which themes are associated with that appearance.
...black hole’s area could be determined by its event horizon. This non-decreasing idea sounded like entropy, or disorder, which the second law of thermodynamics states never decreases. For example, gas molecules... (full context)
...a black hole will reduce its mass. Its event horizon would contract, reducing its internal entropy proportionally to the increase in entropy outside. As the black hole contracts it heats up,... (full context)
...more overall disorder. This means humans, and computers, only remember things in the direction of entropy, making the psychological arrow of time almost trivial, as it is determined by the thermodynamic... (full context)