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Thread: Quantum fluctations and the Universe

  1. #1
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    Quantum fluctations and the Universe

    Hello,

    I hope you are all well and staying safe.

    I was reading a book by Hawking the other night and was confused by one of his statements.
    Hawking said that the laws of physics, and quantum theory in particular, allow for the creation of sub-atomic particles from nothing as long as they dissipate within a short period of time and that the same principle can be used to explain the creation of the universe from nothing.

    Does this mean that the laws of physics were present before the universe was born thus allowing for the quantum fluctuations that led to its birth ? I thought the laws came into existence at the same time the universe did which to me means there couldn't have been any quantum fluctuations before then...

    Pls educate me.

    Thank you.
    Last edited by hush36; 2021-Nov-25 at 10:44 AM. Reason: spelling

  2. #2
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    The laws are our laws, we call models that explain observations well, laws. It is actually unknowable if there were laws before the singularity, physics stops at the singularity. The processes that we think happened and led to the expanding universe are the work of theoretical physics. We cannot repeat the big bang (I hope) but many of the processes are now reproduced in particle accelerators of increasing energy as physics progresses. The universe is not all collisions as you say, there are quantum fluctuations, virtual photons and overall the impression of randomness which is counterintuitive in many ways but the current standard model fits many observations including in quantum experiments. The question of pre-existing laws or existing laws exerted by unknown means is metaphysical. In general physics rejects metaphysical explanations but can never answer the many “why? “ questions. Another physicist you might like to read is Carlo Ravelli, he explores those issues plus time in easy to read books.
    sicut vis videre esto
    When we realize that patterns don't exist in the universe, they are a template that we hold to the universe to make sense of it, it all makes a lot more sense.
    Originally Posted by Ken G

  3. #3
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    Quote Originally Posted by hush36 View Post
    Does this mean that the laws of physics were present before the universe was born thus allowing for the quantum fluctuations that led to its birth ?
    "The laws of nature must have existed before even time began in order for the beginning to happen. We say this, we believe it, but can we prove it? No." [Leon Lederman, The God Particle]
    Everyone is entitled to his own opinion, but not his own facts.

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    Quote Originally Posted by profloater View Post
    It is actually unknowable if there were laws before the singularity, physics stops at the singularity.
    Our current physics doesn't get back to a singularity. Well before that point we reach a domain where our current models are inapplicable.

    We don't know if there was a singularity, we don't know whether the universe operated in the same way prior to the point where our models break down and we don't know if the interactions that govern how things behave were different back then.

    You see/hear a lot of speculation about the very early universe - but that is really all it is. Speculation. Until we have some theories that work in this domain we don't really know what was happening, or even if this is a meaningful question.

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    Quote Originally Posted by hush36 View Post
    ... and that the same principle can be used to explain the creation of the universe from nothing. ...

    Pls educate me.
    You may notice that Hawking never said that it does explain it, only that with what we know so far, and only using the vague loosely defined term "quantum fluctuation" there is an idea for one possibility for a workable explanation ("can be used to explain"). We may be many centuries away from having the ability to rule out ideas of how it all started and narrow the search to a few promising models. If this is something that you feel a strong desire to resolve, then work on it. Help build the scaffolding science that will help us get there.
    Forming opinions as we speak

  6. #6
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    Quote Originally Posted by antoniseb View Post
    If this is something that you feel a strong desire to resolve, then work on it. Help build the scaffolding science that will help us get there.
    Lol, I was asking a question.

  7. #7
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    Thanks to everyone for the replies !

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    Quote Originally Posted by hush36 View Post
    Lol, I was asking a question.
    Well, sure, but did you ask out a burning desire to know, or because you were amused, thinking you'd found a hole in science? Most of us answer to help with the burning desire to understand.
    Forming opinions as we speak

  9. #9
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    The interesting part, is could the disappearance of matter in one part of the universe, cause the creation of matter in another part of the universe.
    The moment an instant lasted forever, we were destined for the leading edge of eternity.

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