Why does time work the way it does?

[Cypress]

Why does time work the way it does? Time is as mysterious as it is familiar. The fundamental laws, ever since Isaac Newton, have a profound feature: they do not distinguish between past and future. They are reversible. But for systems with many moving pieces, there is a pronounced directionality to time.

Explaining why time has an arrow is a primary concern of modern physics. It does not arise from quantum mechanics or particle physics. Rather, it is due to the increase of entropy—a way of measuring how messy or disorderly a system is—as time passes. The increase of entropy is responsible for many deeply ingrained features of time, such as our ability to remember the past or make decisions that affect the future.

The question then becomes: Why does entropy increase? The increase of entropy toward the future is known as the second law of thermodynamics and was explained in modern terms by Ludwig Boltzmann in the 19th century. Boltzmann’s insight is that entropy increases because there are more ways for a system to have high entropy than low entropy; thus, high entropy is a natural condition.

This raises a new question: Why was entropy lower in the past? That turns out to be a much harder problem, one that traces back to the very beginning of time. The low entropy of the past is ultimately due to the fact that our universe had low entropy 13.7 billion years ago. Somehow, our Universe must have avoided all those high entropy states and started in a very unlikely, very low entropy state. Physicists and philosophers call this the past hypothesis. But what makes this hypothesis correct? Why did the Universe begin in such an unlikely state that allowed us to emerge? We do not want to invoke an intelligent designer to make the choice for us — that would be a flagrant case of special pleading.

Cosmology would like to explain why the Big Bang had low entropy, but our best current models aren’t up to the task. It’s possible that the ultimate explanation might lie beyond our observable cosmos, in a larger multiverse.




Source credits:
course guidebook “Mysteries of Modern Physics: Time”, Sean Carrol, CalTech
And
[url="https://bigthink.com/13-8/the-past-hypothesis-universe/#:~:text=It%20would%20experience%20no%20change,call%20this%20the%20past%20hypothesis]Our best models of the Universe have a troubled past [/url]

 

[Cypress]

 

[IBDaMann]

Why does time work the way it does?

The 2nd law of thermodynamics is what gives time a directional axis.

Explaining why time has an arrow is a primary concern of modern physics.

Nope, physicists aren't concerned. The 2nd law of thermodynamics explains it all thoroughly.

Rather, it is due to the increase of entropy—a way of measuring how messy or disorderly a system is—as time passes.

This is the gross miswording of laymen. The subjective nature of the words "messy" and "disorderly" immediately broadcasts that there is a problem here. Science doesn't touch the subjective.

The 2nd law of thermodynamics is all about the quantity of usable energy available to perform work in a closed system. This quantity is absolute, objective and strictly decreases as work is performed. In a car, the gasoline represents the amount of usable energy to perform work (i.e. drive around). As you drive, the amount of gasoline strictly decreases and never increases.

Focusing on entropy will only confuse matters. Those who aren't experts in thermodynamics should focus on "quantity of usable energy", e.g. the gasoline in a car, the hydrogen in a star, the coulombs in a battery, etc. The concept of entropy is actually not needed.

The question then becomes: Why does entropy increase?

Because the quantity of usable energy decreases. Entropy is simply Total_Energy - Usable_Energy. It's just math, and it's why the term entropy is really not needed. All that is really needed is the initial quantity of usable energy and its rate of decrease as work is performed. Once all of the usable energy is expended, no more work can be performed. Done.

The increase of entropy toward the future is known as the second law of thermodynamics and was explained in modern terms by Ludwig Boltzmann in the 19th century. Boltzmann’s insight is that entropy increases because there are more ways for a system to have high entropy than low entropy; thus, high entropy is a natural condition.

Cypress, you totally blew that one. Boltzmann was extremely competent at math. He was quite capable of performing subtraction, i.e. calculate entropy by subtracting usable energy from total energy.

Boltzmann's primary contribution was the derivation of the Stefan-Boltzmann law which kills greenhouse effect dead. It really was quite the testament to his proficiency in math; mere subtraction was well within his repertoire.

This raises a new question: Why was entropy lower in the past?

There is no "why" in science. That is a theological question. As an atheist, all that matters to me is that the quantity of usable energy within a closed system strictly decreases over time. The question of "why" it is that way is for theists to ponder per their respective faiths.

The low entropy of the past is ultimately due to the fact that our universe had low entropy 13.7 billion years ago.

Now you are claiming omniscience. You like to do that. I would mention that you are actually not omniscient and your commentary to that effect is ignored.

Physicists and philosophers call this the past hypothesis.

Nope. They call it their "speculation."

But what makes this hypothesis correct?

The assumption of omniscience ... which happens to be a fallacy.

Why did the Universe begin in such an unlikely state that allowed us to emerge?

What makes you think it was an unlikely state ... as opposed to being the only possible state in which the universe could begin? Or what makes you think that the big bang even happened, as opposed to the continuum theory which states that the universe always existed and that there was never any "big bang"? Nobody knows the unobserved past, but many who are desperate for attention nonetheless claim to know.

We do not want to invoke an intelligent designer to make the choice for us — that would be a flagrant case of special pleading.

You are getting your fallacies confused. Belief in an intelligent designer is not a case of special pleading; it is a religious faith.

When you claim omniscience, it's a fallacy on your part, not a fallacy on the part of Christians.

Cosmology would like to explain why the Big Bang had low entropy,

Nope. Cosmology is not trying to cut into the religion business. Cosmologists are fine with speculating; they don't feel any need to claim omniscience.

 

[Cypress]

^^ posting and frantically Googling all Saturday night long = no wife, no girlfriend, no social life.


CLICK HERE: IBDumbass does not post in good faith; he hounds me with what he believes is a 'gotcha!' question, but when it blows up in his face he runs away from the thread like a little girl

hint: energy and matter are not interchangeable

The Theory of the Big Bang is just a nonscientific theory

Wave-Particle duality is classical physics.

There is no such thing as an accelerating reference frame!!

There is no such thing as an 'accelerating frame of reference'.

Darwin's theory of evolution is not science

Bulverism fallacy. Bigotry.

Bulverism. Bigotry. False Authority.

bigotry, bulverism

 

[Into the Night]

Why does time work the way it does? Time is as mysterious as it is familiar. The fundamental laws, ever since Isaac Newton, have a profound feature: they do not distinguish between past and future. They are reversible. But for systems with many moving pieces, there is a pronounced directionality to time.

Explaining why time has an arrow is a primary concern of modern physics. It does not arise from quantum mechanics or particle physics. Rather, it is due to the increase of entropy—a way of measuring how messy or disorderly a system is—as time passes. The increase of entropy is responsible for many deeply ingrained features of time, such as our ability to remember the past or make decisions that affect the future.

The question then becomes: Why does entropy increase? The increase of entropy toward the future is known as the second law of thermodynamics and was explained in modern terms by Ludwig Boltzmann in the 19th century. Boltzmann’s insight is that entropy increases because there are more ways for a system to have high entropy than low entropy; thus, high entropy is a natural condition.

This raises a new question: Why was entropy lower in the past? That turns out to be a much harder problem, one that traces back to the very beginning of time. The low entropy of the past is ultimately due to the fact that our universe had low entropy 13.7 billion years ago. Somehow, our Universe must have avoided all those high entropy states and started in a very unlikely, very low entropy state. Physicists and philosophers call this the past hypothesis. But what makes this hypothesis correct? Why did the Universe begin in such an unlikely state that allowed us to emerge? We do not want to invoke an intelligent designer to make the choice for us — that would be a flagrant case of special pleading.

Cosmology would like to explain why the Big Bang had low entropy, but our best current models aren’t up to the task. It’s possible that the ultimate explanation might lie beyond our observable cosmos, in a larger multiverse.




Source credits:
course guidebook “Mysteries of Modern Physics: Time”, Sean Carrol, CalTech
And
[url="https://bigthink.com/13-8/the-past-hypothesis-universe/#:~:text=It%20would%20experience%20no%20change,call%20this%20the%20past%20hypothesis]Our best models of the Universe have a troubled past [/url]

Still trying to deny the 2nd law of thermodynamics, eh?

 

[Saint Guinefort]

^^ posting and frantically Googling all Saturday night long = no wife, no girlfriend, no social life.

While I don't think IBDAman is necessarily any better with science than you are, Cypress, it fascinates me how scared you get that someone might know more than you do. Anytime someone so much as disagrees with you and provides actual science you ALWAYS claim they must be "frantically googling".

Your stumble with the freezing point depression was all I needed to see to know you frantically google with the best of 'em. You don't know what your posting most of the time, but it sounds science-y to you so you post it in DESPERATE HOPES that people will think you smarter than you actually are.

Pitiful, actually.

 

[Into the Night]

^^ posting and frantically Googling all Saturday night long = no wife, no girlfriend, no social life.

He does not need to 'frantically Google' to state the 2nd law of thermodynamics you are ignoring.

CLICK HERE: IBDumbass does not post in good faith; he hounds me with what he believes is a 'gotcha!' question, but when it blows up in his face he runs away from the thread like a little girl

Paranoia. Hallucination.

 

[Saint Guinefort]

He does not need to 'frantically Google' to state the 2nd law of thermodynamics you are ignoring.

Paranoia. Hallucination.

You and your socks know next to nothing of science, but that's good because GoogleMaster Cypress doesn't know much more than you do! It's fun to see you guys argue about stuff you have ZERO CLUE about.

 

[AProudLefty]

The 2nd law of thermodynamics is what gives time a directional axis.


Nope, physicists aren't concerned. The 2nd law of thermodynamics explains it all thoroughly.


This is the gross miswording of laymen. The subjective nature of the words "messy" and "disorderly" immediately broadcasts that there is a problem here. Science doesn't touch the subjective.

The 2nd law of thermodynamics is all about the quantity of usable energy available to perform work in a closed system. This quantity is absolute, objective and strictly decreases as work is performed. In a car, the gasoline represents the amount of usable energy to perform work (i.e. drive around). As you drive, the amount of gasoline strictly decreases and never increases.

Focusing on entropy will only confuse matters. Those who aren't experts in thermodynamics should focus on "quantity of usable energy", e.g. the gasoline in a car, the hydrogen in a star, the coulombs in a battery, etc. The concept of entropy is actually not needed.


Because the quantity of usable energy decreases. Entropy is simply Total_Energy - Usable_Energy. It's just math, and it's why the term entropy is really not needed. All that is really needed is the initial quantity of usable energy and its rate of decrease as work is performed. Once all of the usable energy is expended, no more work can be performed. Done.


Cypress, you totally blew that one. Boltzmann was extremely competent at math. He was quite capable of performing subtraction, i.e. calculate entropy by subtracting usable energy from total energy.

Boltzmann's primary contribution was the derivation of the Stefan-Boltzmann law which kills greenhouse effect dead. It really was quite the testament to his proficiency in math; mere subtraction was well within his repertoire.


There is no "why" in science. That is a theological question. As an atheist, all that matters to me is that the quantity of usable energy within a closed system strictly decreases over time. The question of "why" it is that way is for theists to ponder per their respective faiths.


Now you are claiming omniscience. You like to do that. I would mention that you are actually not omniscient and your commentary to that effect is ignored.


Nope. They call it their "speculation."


The assumption of omniscience ... which happens to be a fallacy.


What makes you think it was an unlikely state ... as opposed to being the only possible state in which the universe could begin? Or what makes you think that the big bang even happened, as opposed to the continuum theory which states that the universe always existed and that there was never any "big bang"? Nobody knows the unobserved past, but many who are desperate for attention nonetheless claim to know.


You are getting your fallacies confused. Belief in an intelligent designer is not a case of special pleading; it is a religious faith.

When you claim omniscience, it's a fallacy on your part, not a fallacy on the part of Christians.


Nope. Cosmology is not trying to cut into the religion business. Cosmologists are fine with speculating; they don't feel any need to claim omniscience.

Whoooosh!

 

[Cypress]

Some physicists think the reasoning is flawed

The problem with conflating the entropy's directionality with the arrow of time is that the second law of thermodynamics says that entropy in a closed system either increases or stays the same. But in a system where entropy stays the same, time does not stop. Time moves forward at the same rate as systems where entropy is increasing.

 

[IBDaMann]

Whoooosh!

This is the typical result when you tax your brain. Just skip over the posts you don't understand.

 

[AProudLefty]

This is the typical result when you tax your brain. Just skip over the posts you don't understand.

Q.E.D.

 

[PostmodernProphet]

time does not work......it only gets up and leaves the moment it gets here.......

 

[NiftyNiblick]

Why does time work the way it does? Time is as mysterious as it is familiar. The fundamental laws, ever since Isaac Newton, have a profound feature: they do not distinguish between past and future. They are reversible. But for systems with many moving pieces, there is a pronounced directionality to time.

Explaining why time has an arrow is a primary concern of modern physics. It does not arise from quantum mechanics or particle physics. Rather, it is due to the increase of entropy—a way of measuring how messy or disorderly a system is—as time passes. The increase of entropy is responsible for many deeply ingrained features of time, such as our ability to remember the past or make decisions that affect the future.

The question then becomes: Why does entropy increase? The increase of entropy toward the future is known as the second law of thermodynamics and was explained in modern terms by Ludwig Boltzmann in the 19th century. Boltzmann’s insight is that entropy increases because there are more ways for a system to have high entropy than low entropy; thus, high entropy is a natural condition.

This raises a new question: Why was entropy lower in the past? That turns out to be a much harder problem, one that traces back to the very beginning of time. The low entropy of the past is ultimately due to the fact that our universe had low entropy 13.7 billion years ago. Somehow, our Universe must have avoided all those high entropy states and started in a very unlikely, very low entropy state. Physicists and philosophers call this the past hypothesis. But what makes this hypothesis correct? Why did the Universe begin in such an unlikely state that allowed us to emerge? We do not want to invoke an intelligent designer to make the choice for us — that would be a flagrant case of special pleading.

Cosmology would like to explain why the Big Bang had low entropy, but our best current models aren’t up to the task. It’s possible that the ultimate explanation might lie beyond our observable cosmos, in a larger multiverse.




Source credits:
course guidebook “Mysteries of Modern Physics: Time”, Sean Carrol, CalTech
And
Our best models of the Universe have a troubled past

Time is fairly simple to me.
I'm not saying that it is actually simple,
but it's simple for all of my practical applications.

It's based on the earth's orbit around the sun as well as it's own revolutions.

That established the units in real time.

Once that standard unit is codified, it's applicable anywhere,
even elsewhere in the universe,
even if our earth and our sun cease to exist.

That's why I find it easier to imagine forward infinity...more of the same shit forever--

than backward infinity.

There can't be a beginning of any kind because.... what came before that?

That's what I can't understand. I'm fine with the measuring units but the final calculation never comes

...as measured in my previously described codified units, going from milliseconds to millennia.


That's the key. There was no time before this or before that happened, a cosmologist,
or even a cosmetologist ,
is likely to say,
but I've got the defined units by which I want to measure. Just use them.

But we can't ever arrive at the final answer because the concept of a "beginning" is undefinable.
Not as long as the concept of "before" still exists in my mind.

 

[Cypress]

While I don't think IBDAman is necessarily any better with science than you are, Cypress, it fascinates me how scared you get that someone might know more than you do. Anytime someone so much as disagrees with you and provides actual science you ALWAYS claim they must be "frantically googling".

Your stumble with the freezing point depression was all I needed to see to know you frantically google with the best of 'em. You don't know what your posting most of the time, but it sounds science-y to you so you post it in DESPERATE HOPES that people will think you smarter than you actually are.

Pitiful, actually.

You're welcome waste your time debating with a poster who writes stupidity like this. Why don't you tell him about your glorious geochem PhD

hint: energy and matter are not interchangeable

The Theory of the Big Bang is just a nonscientific theory

Wave-Particle duality is classical physics.

Darwin's theory of evolution is not science

CLICK HERE: IBDumbass does not post in good faith; he hounds me with what he believes is a 'gotcha!' question, but when it blows up in his face he runs away from the thread like a little girl

 

[IBDaMann]

The problem with conflating the entropy's directionality with the arrow of time is that ...

This doesn't make any sense. The 2nd LoT is what gives the time axis direction ... and I don't think "directionality" is a word.

... the second law of thermodynamics says that entropy in a closed system either increases or stays the same.

The usable energy in a closed system always decreases, but sometimes the rate of decrease is negligible by our measure and we say "remains the same" in such situations. Nonetheless, a car with a full tank of gasoline that is somehow left parked and unused for six years, won't have the equivalent of a full tank of usable gasoline. Similarly, most fully charged batteries, if left unused in storage for many years will lose most to all of their charge. The ability to perform work in a closed system always decreases, but to remain practical we also include the clause "or remains the same."

But in a system where entropy stays the same, time does not stop.

So? In a system in which the rate of decrease of usable energy changes, time neither speeds up nor slows down.

 

[Cypress]

Bulverism 41

hint: energy and matter are not interchangeable

The Theory of the Big Bang is just a nonscientific theory

Wave-Particle duality is classical physics.

Darwin's theory of evolution is not science

CLICK HERE: IBDumbass does not post in good faith; he hounds me with what he believes is a 'gotcha!' question, but when it blows up in his face he runs away from the thread like a little girl

 

[IBDaMann]

It's based on the earth's orbit around the sun as well as it's own revolutions.

The earth's orbits around the sun are its revolutions, and the earth's rotations about its axis are its rotations.

That established the units in real time.

The problem with using the orbits and rotations of planets and/or celestial bodies is that they change over ... wait for it ... time!

Once that standard unit is codified, it's applicable anywhere, even elsewhere in the universe,

Nope. Not orbits or rotations. This is why time is no longer defined by earth's rotation. You might think that one second is defined as 1/60th of 1/60th of 1/24th of an earth's rotation, but it is not. For those who have an understanding of Relativity, one earth rotation represents a different amount of time to an observer in a different inertial frame of reference, so no, it certainly is not applicable anywhere, and that defeats the purpose of unit of measure.

One second is defined by the radiation of a cesium isotope. That is the same amount of time regardless of one's inertial frame of reference and yes, it is applicable anywhere and everywhere.

That's why I find it easier to imagine forward infinity...more of the same shit forever-- than backward infinity.

It's actually quite easy to imagine "backward infinity" by imagining yourself observing the universe as an external observer to the universe. Imagine the universe getting slower and slower as you go back in time towards the singularity as time itself within the universe begins dilating (slowing down) more and more. Imagine that it begins to take two seconds of your time for one second of time to occur in the universe, like someone turned on the slow motion. Eventually it takes three seconds of your time for the universe to complete one second of its time. Then it takes four seconds, five seconds, six seconds ... it starts to get very slow. After a long while, it starts to take years of your time for the universe to move back in time just one second. Eventually it gets to the point that it takes centuries for one second of advancement, and then it takes millennia. At the singularity, it will take infinite time to move one second, i.e. you will never get there. You will be going back in time forever without ever reaching the point of the Big Bang, i.e. the singularity, as time becomes infinitely slow.

Then there is the theory of the continuum in which there was never any beginning. Just imagine that you're sitting in the universe, traveling backward through time observing something that is getting slower and slower and slower, as in the example above. You will be studying it forever in your universe without a beginning as you travel back in time forever.

There can't be a beginning of any kind because.... what came before that?

Did you not have a beginning? I mean, what came before you? Also, those who believe that time itself began at the Big Bang do not believe there was any time prior to that.

but I've got the defined units by which I want to measure.

Nope. It doesn't look like you have the units, but I can give them to you: Cesium-133 radiates very stably at 9,192,631,770 Hz, ergo, one second is 9,192,631,770 cycles of Cesium-133 radiation.

But we can't ever arrive at the final answer because the concept of a "beginning" is undefinable.

It's definitely definable. In fact, the definition is what serves as the basis for acceptance or rejection of the model. There are posters on JPP who reject the Hawking definition of the singularity, and yet others on JPP reject the idea of no singularity ever. Fortunately, international markets and the global economy are not tied to any particular model of the universe.

 

[Into the Night]

You and your socks know next to nothing of science, but that's good because GoogleMaster Cypress doesn't know much more than you do! It's fun to see you guys argue about stuff you have ZERO CLUE about.

I have no sock, Sock. You are only describing yourself again.

 

[Into the Night]

The problem with conflating the entropy's directionality with the arrow of time is that the second law of thermodynamics says that entropy in a closed system either increases or stays the same. But in a system where entropy stays the same, time does not stop. Time moves forward at the same rate as systems where entropy is increasing.

Because there are systems where entropy is increasing.