The Impact of Maxwell’s Daemon

 

The 19th Century scientist, James Clerk Maxwell, comes to life almost instantly whenever science enthusiasts reflect upon the 2nd Law of Thermodynamics. Such is the impact that he has left with his thought experiment, commonly known as Maxwell's Daemon, devised in 1867.

The Purpose

The second law of thermodynamics asserts that the disorder or the universe's entropy will only increase over time. Maxwell's intention behind formulating the notion of the 'being' or daemon was never to negate the science but to show us the possibility of hypothetically breaking the statistical nature of this law.  

As per the science behind thermodynamics, things are destined to fall apart or collapse. The daemon suggested that they can be put back together without any work, i.e., entropy can be reversed using Information. 

 

 
 
 
 
 
 
 
 
 
 
Feature 01

The Paradox

To explain the thought experiment in simple terms- imagine building a fridge next to an oven without expending any energy. Maxwell argued that it is possible to make one side colder and the other half hotter by knowing what is happening inside two chambers (divided by a sliding door) filled with air molecules.

Feature 02

Proof of Concept

To prove this, he conjured a small 'being' sitting atop the chambers (A & B) who could see the velocity at which all the molecules inside the chambers moved. The division had a hole that the being can open and close —allowing the faster molecules to pass from the left to the right chamber (picture below) and the slow-moving particles to pass from the right to the left chamber. Thus, sorting all the hot (fast-moving) molecules in the chamber B and the cold (slow-moving) molecules to chamber A without expending work.

2nd Law of Thermodynamics

 

That's how the 2nd law of thermodynamics gets violated as the temperature inside chamber A is lowered and raised inside chamber B, using Information alone. Maxwell's imaginary being prevents the thermodynamic system's equilibrium (reduces entropy) by merely observing the motion of the molecules and ordering them into separate chambers.

However, scientists eventually concluded that we could not know the molecules' energy state individually because there is no tiny being with a massless trapdoor. Thus, the 2nd law remains safe.

 

The Impact

The renowned physicist raised the argument as more of a concern and left it unresolved, which followed years of scientists debating and trying to address and solve the astonishing idea. It is interesting to notice the magnitude of impact and inspiration Maxwell had on modern physics with this intricate concept, which in some ways anticipated the notion of Information that was at his time non-existent.

Later in the story, Leo Szilard made the first clear connection between the notion of Information & thermodynamics in one of his key papers. It can thus, be a referral point for the area of the emergence of information theory and modern computing. According to his principle about Maxwell's daemon, the chambers' reduced entropy can be balanced out by increased entropy in the daemon's brain, i.e., the entropy cost of gathering the Information.

In the early 1960s, Rolf Landauer said there was no need to expend any energy (entropy cost) for the daemon to acquire the Information. However, the question about the expenditure of energy remains an open question to date. Various ideas like algorithm randomness and more have been emerging to clear the paradox of the daemon further.

Resources

https://en.wikipedia.org/wiki/James_Clerk_Maxwell

https://mylearntogether.com/free-homeschool-resources/

https://en.wikipedia.org/wiki/Maxwell%27s_demon#:~:text=Maxwell's%20demon%20is%20a%20thought,between%20two%20compartments%20of%20gas.

https://www.britannica.com/topic/Project-Mac

https://www.studyplans.com/languages.html

https://amturing.acm.org/award_winners/corbato_1009471.cfm