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Question on Gravity, Big Bang, Dark Energy and Black Holes

  1. Nov 11, 2013 #1
    Sorry to have such a broad subject line but I was in a contimplative mood yesterday and the mind was wondering and pondering…

    From the publication of Sir Isaac Newton,”Philosophiæ Naturalis Principia Mathematica”, the science world has been challenging the findings around gravity proposing that everything should collapse on itself over time. One suggestion was that there are an infinite number of stars across an infinite galaxy and another suggestion was that once the gravitation pull reaches a certain distance, it may have a negative or repulsive effect. Which was dismissed at the time.

    As we don’t understand how gravity works, could it be possible that the latter suggesting, that when the distance between objects reach a certain distance, that they are repelled from each other?
    Like the effect of an elastic band pulling two objects together, if pulled far enough apart, the elastic band snaps and objects are actually pushed apart….

    So from the time of the big bang, where it is suggested that the universe exploded from a singularity, everything was pushed out and expanded massively. Now, in some point of time, according to the laws of gravity, all the mass in the universe would collapse back on itself (The Big Crunch). However, from recent developments we understand that the universe is not only expanding, but the expansion is accelerating and may never collapse back on itself.

    Could it be, that the dark energy suggested in some theories is created when gravity between objects is extended beyond its limits and changes the fabric of gravity as a force…?

    Would love to hear members thoughts on this.
  2. jcsd
  3. Nov 12, 2013 #2

    Simon Bridge

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    Well of course - all kinds of things could be happening. But that's rather begging the question.

    You need to revise the idea that the "big bang" is any kind of explosion into anywhere from anywhere.
    Whether or not there would be a "big crunch" depends on the amount of mass vs the initial kinetic energy of all the bits moving apart. Just because you have a big bang, you don't have to have a big crunch.

    Sure but where does that get you?
    The point of the "dark energy" hypothesis is that it suggests a mechanism besides just stating what happens.
    In this case, a mechanism that fits within known physics.
    Models that require extra forces run foul of Occam's Razor.
    At any time there are hundreds, if not thousands, of possible models covering currently unknown stuff - each a kind-of scientific god-of-the-gaps. Which should we turn our attention to?
    They may still turn out to be true but we should consider them when the simpler models turn out to be unworkable.
  4. Nov 12, 2013 #3
    thanks for your response Simon. Just trying to put ideas out there that physicists might not have thought about.... and to be honest, I like thinking about possibilities.
  5. Nov 12, 2013 #4

    D H

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    That is extremely arrogant on your part.

    Don't express those thoughts at this site. You agreed to abide by the rules of the site when you joined, but did you read those rules or did you just click "Yes"? Personal theories are not allowed here.

    While you are not free to espouse your personal theories on the origin of the universe, you are quite free to ask questions about topics you don't understand. There are a number of highly educated people who visit this site who are more than glad to help you come to some level of understanding.
  6. Nov 12, 2013 #5

    Simon Bridge

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    The cosmological constant was considered to be just such a thing - an extra force or property of gravitation that takes over at long ranges. i.e. thought of already.

    Not to say that old ideas cannot be revisited.

    Thinking up possibilities is fun.
    However - that kind of speculation is off-topic for these forums.
    You'll find people here will steer you towards the standard or mainstream models in each category.
    It is a good idea to understand those before trying to advance them.

    You'll also find that, after a while, you realize that pretty much anything you can think of without that understanding will have been thought of before.
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