# Why are the laws of physics what they are?

In physics, at least at my level of knowledge and understanding, a lot of the most basic facts of reality start to seem a bit arbitrary. Mostly this seems to be the case with the various universal constants such as the speed of light or plank's length or the gravitational constant. So what I would like to know is if there is some reason why those constants are what they are or is it all just coincidence or chance, or is that maybe something that is impossible to ever know?

jedishrfu
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The truth is we have no answers to your questions. These are things we hope to know someday.

The reality of physics is that try to understand the workings of the universe using theories we construct using mathematical concepts.

We tune the models using experiments to measure key constants and then we begin to apply the theories to make predictions that we can test experimentally.

The mystery is why does the math work so well across so many fields of physics. This mystery gives us hope that we will find a single theory that describes the universe.

Having said that we can see how difficult our journey to a single theory will be as seek to understand the deep meaning of quantum mechanics. A theory which defies our common sense and yet works so well in the subatomic realm.

Nova did a show called The Great Math Mystery on this very subject.

https://www.pbs.org/video/nova-great-math-mystery/

Darn, that's too bad. Still, I figured that there was a decent possibility of that being the case going in. Still, even if there are no concrete answers, do you know if there are any common of popular hypotheses going around the scientific community on the subject? In any case, thanks for the answer, and I'll be sure to check out that video!

Delta2
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Gold Member
Well, I can find some reasons as to why for example the gravitational constant is so small, because if it was much bigger then the miracle of life in planet earth wouldn't be possible, at least not for organisms of medium or large size, because they would collapse under their own weight...

But I guess this reasoning might not be so satisfying (so what if there would be no medium to large organisms???), I believe however that there is God and God made the universe and the laws of the universe and gave specific values to the constants of the universe . Trying to answer your question is kind of like trying to enter the mind of God.

paul15
PeroK
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2020 Award
Well, I can find some reasons as to why for example the gravitational constant is so small, because if it was much bigger then the miracle of life in planet earth wouldn't be possible, at least not for organisms of medium or large size, because they would collapse under their own weight...

But I guess this reasoning might not be so satisfying (so what if there would be no medium to large organisms???), I believe however that there is God and God made the universe and the laws of the universe and gave specific values to the constants of the universe . Trying to answer your question is kind of like trying to enter the mind of God.
That answer got me thinking. I wonder if there are advanced physics courses in heaven? It would give you something to do to pass the time.

Delta2
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Gold Member
That answer got me thinking. I wonder if there are advanced physics courses in heaven? It would give you something to do to pass the time.
Once you pass the gates to heaven you instantaneously gain all knowledge about the laws of physics ….

But ok seriously I know God's existence cannot be supported by data gathered and analysed according to the principles of the scientific method.(for example scientists did experiments, data measurements and data analysing and concluded that quarks exist, we cant conclude God's existence in the same way). All we have are some written documents of the past (bible and others) that I know are of little to no scientific value. Still I believe in God. I absolutely respect your right to be an atheist.

And ok I know that if we refer to God, we put the thread in danger to be locked, don't lock the thread , instead just remove or edit my posts if you find my posts non scientific.

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Another way of looking at it is to redefine what "god" really means. I'm a scientist, and I consider myself an atheist when it comes to any of the religious definitions of god. Show me your proofs, right?

However, if you define "god" as "the structure and behaviour of the entire universe, including what we call physics, that we are all a part of" then that makes logical sense to me.

All available evidence points to us (as individual people) simply being temporary amalgamations of energy/mass and connected to everyone/everything else. That alone is a concept worthy of awe and belief, one that can guide how you behave in this world.

"god" in this sense is not a sentient being analagous to us but bigger, any more than one of our own cells is like us.

CWatters
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Gold Member
You might enjoy The Grand Design by Stephen Hawking and Leonard Mlodinow. I'm about half way through. Just got to the bit where they explain how experiment (appear) to show how we can influence the past.

jtbell
Mentor
Q: Why are Maxwell's equations for electromagnetism the way they are?

A: Because of local U(1) gauge symmetry.

Q: OK, then why is there local U(1) gauge symmetry?

A: Uh...

You can do the same thing for anything in physics, except that you might need one or two more levels of Q&A.

PeroK
PeroK
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2020 Award
Q: Why are Maxwell's equations for electromagnetism the way they are?

A: Because of local U(1) gauge symmetry.

Q: OK, then why is there local U(1) gauge symmetry?

A: Uh...

You can do the same thing for anything in physics, except that you might need one or two more levels of Q&A.
I'd like to see God's response to that!

DennisN
2020 Award
or is that maybe something that is impossible to ever know?
That is impossible to say. At least I think so.
So what I would like to know is if there is some reason why those constants are what they are or is it all just coincidence or chance, or is that maybe something that is impossible to ever know?
Yes. There is a reason, it is because we use base 10 for our numbers.
Seriously, what's more interesting are the dimensionless ratios between various constants like e.g. the fine structure constant $α$ and the proton to electron mass ratio.

See e.g. this article on fundamental constants: How Many Fundamental Constants Are There?
and this thread for some discussion on these matters: Why is the fine structure constant what it is?

Delta2
pinball1970
Gold Member
Once you pass the gates to heaven you instantaneously gain all knowledge about the laws of physics ….

But ok seriously I know God's existence cannot be supported by data gathered and analysed according to the principles of the scientific method.(for example scientists did experiments, data measurements and data analysing and concluded that quarks exist, we cant conclude God's existence in the same way). All we have are some written documents of the past (bible and others) that I know are of little to no scientific value. Still I believe in God. I absolutely respect your right to be an atheist.

And ok I know that if we refer to God, we put the thread in danger to be locked, don't lock the thread , instead just remove or edit my posts if you find my posts non scientific.
I don't think the comment should be removed as there are comparisons with god and string theory.

Both are neat theories that explain the universe but come in countless versions with no hard data to verify them.

Delta2
jedishrfu
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