Why does time flow forward?

Feb 13, 2023,11:43 AM

As a watch enthusiast and a person who is deeply fascinated by science, I felt like this could be a good idea for a post (keep in mind that I am not an expert in any of the things I'm talking about). One of the reasons why I love watchmaking is the fact that I find the concept of time extremely interesting. I'm here to talk about an english astronomer and physicist by the name of Sir Arthur Eddington, who came up with a theory about why time moves forward.

First of all it's important to have a base understanding of what Thermodynamics is: Thermodynamics is the field of Physics that studies energy and its conversion from one form to another. The second law of Thermodynamics is what we're concerned about: it states that the entropy of an isolated system is always increasing.

What is entropy and why does it always increase? Entropy is the physical quantity that expresses the disorder of a system: the higher it is, the higher the disorder. For a chemical reaction to happen spontaneously, entropy needs to increase. Increasing entropy could mean the molecules of a gas being spaced out over a bigger volume, or a higher temperature that results in those molecules moving faster. Overall, the higher the entropy, the higher the amount of information needed to describe the system will be. Describing the "placement" of gas molecules in a cubic centimetre of space is easier than describing the possible arrangement of those same molecules in a space of one cubic metre, as it requires less information.

At the big bang (not the Unico kind wink ), all matter was condensed into a really tight space, which means that entropy was the lowest it has ever been. As time moved forward, entropy kept on increasing, resulting in the expansion of the universe and every single process taking place inside of it. This is why we can't travel back in time: the overall entropy of the universe would have to decrease, and that is impossible.

As the universe moves forward and reaches a state of thermal equilibrium, time could stop, as entropy is at its maximum. This could mean that time isn't as eternal as we may have thought when we were the lower entropy version of ourselves.

More posts: Big Bang

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I never thought this counted as an explanation

 By: blau : February 13th, 2023-12:03
The second law of thermodynamics--the idea that entropy must always increase--itself assumes the directionality of time. 'Increase' relative to what? The PREVIOUS entropy level!
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 By: andrea~ : February 13th, 2023-12:05
In order to travel back in time you would need to reverse every single chemical process in the universe, which would mean going from a state of higher to a state of lower entropy, which is impossible according to Thermodynamics.
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 By: InHavenPro : February 13th, 2023-21:56
Just travel faster than the speed of light in order to escape the 'light cone' that our universe resides in....
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Easy peasy 😆

 By: andrea~ : February 13th, 2023-22:06
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I think yo will like this video. But you will have to see it until the end.

 By: aWtchslvr : February 13th, 2023-14:55
https://m. Best.
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Cool! Thanks for the suggestion.

 By: andrea~ : February 13th, 2023-15:52
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In Block Universe theory, time and entropy would only appear to be one directional due to limitations of human perception since the past, present, and future all exist simultaneously.

 By: Emil Wojcik : February 13th, 2023-15:48
General relativity first gave us the basis for the block universe. Just thought I'd add some additional confusion to your question.
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haha confusion is always welcome

 By: andrea~ : February 13th, 2023-15:51
That is interesting. I'll look further into block universe theory
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I just found this article that, after a quick scan, describes the basics of the Block Universe. There's no shortage of papers and articles on the subject so you'll be able to find one at whatever level you're comfortable with.

 By: Emil Wojcik : February 13th, 2023-16:08
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 By: andrea~ : February 13th, 2023-16:19
I'll give it a read
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If the universe reaches a state of thermal equilibrium and time stops…

 By: kev09 : February 13th, 2023-17:27
…do you think Rolex will reduce the price of their watches? ) Sorry, couldn’t resist! Regards Kev.
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A daytona will probably go for 2000x retail by then 🤣

 By: andrea~ : February 13th, 2023-18:18
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He he😆

 By: kev09 : February 13th, 2023-19:11
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You're going to love....

 By: InHavenPro : February 13th, 2023-22:53
this T-Shirt designed by Dr. Sean Carroll which I bought a while back.... We exist at one of the most favorable points in time relative to the entropy vs complexity balance ........ ...  
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I love it!

 By: andrea~ : February 14th, 2023-08:08
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I actually....

 By: InHavenPro : February 14th, 2023-08:20
found a link to the site that sells his T-Shirt designs (TeePublic), so I'll text it to you in a PM. They are a very reasonable 24 EUR in case you are interesting in getting one or more. There are even two color schemes available for this same design! Fin... 
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My understanding of entropy is a bit different ...

 By: COUNT DE MONET : June 6th, 2023-19:11
High entropy does not simply mean big dissorder. Example: A sand castle has low entropy because there is only one way (or very few) to form it as a castle, make it look like a castle. A sand pile instead has high entropy, because there are trillion of tri... 
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It’s a cycle

 By: Stirling Newall : September 3rd, 2023-07:53
Time does not flow forward - time does not exist. Only change exists. All change is cyclical. The ocean evaporates and clouds form, clouds condense, rain falls, rivers flow, water returns to the ocean. There is no time only cyclical change. Everything you... 
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