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How inflation solves the horizon problem

  1. Aug 25, 2012 #1
    Hi Guys

    I've just made a sheet illustrating the horizon problem and how it is solved by inflation.
    I thought it might be handy for anyone interested in it, or having trouble with it. I'd also appreciate it if some of you could check it over and see if there's anything I have gotten wrong.

    I did find a thread with a similar title, but it appeared to be talking about the hubble length when i read into it, rather than the basics like this.

    Any feedback would be great cheers


    Attached Files:

  2. jcsd
  3. Sep 5, 2012 #2
    Anyone? Just after an opinion as to whether people think what ive written is correct

  4. Sep 5, 2012 #3


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    I can't read the thumbnail sheet. Tried to zoom in to 200% using my browser (IE) but still unreadable.
  5. Sep 6, 2012 #4


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    Soph, Sorry, but that Word document is NOT useful at all. It has no diagrams like your first try, and no explanations of how Inflation solves the Horizon Problem. (It doesn't even pass spellcheck.) Please click on it yourself and see. It's important to check these things yourself first, otherwise you can not expect any constructive criticisms or compliments.

  6. Sep 6, 2012 #5


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    Soph, I think your original write-up looks good and makes sense.
  7. Sep 6, 2012 #6
    Really sorry, i Got confused and uploaded the wrong document. This is the one I meant to upload


    Attached Files:

  8. Sep 6, 2012 #7
    Ah only just noticed your reply, so the original image worked, cool :)

    Thanks for having a look and giving feedback :D

  9. Sep 6, 2012 #8
    Be careful how you use the word "solved". You make it sound like inflation theory has been proven.

    On the contrary, there are models of spacetime (re: emergent space) that do not require inflation to explain the horizon problem.

    Good luck!
  10. Sep 17, 2012 #9
    Its still kind of a solution though, just maybe not the right one. I'm sure that 'there's two possible solutions' could form part of a sentence and is correct English... that implies you can have 'a' solution which isn't the only solution. But yeah, i get what you're saying :D

    Variable speed of light is another possibility!

    Cheers :)
  11. Sep 19, 2012 #10


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    There's nothing wrong with using the word 'solved' here. The standard big bang model had a problem, inflation was put forward and shown to remove this problem, therefore that problem is solved.

    There are other solutions, but inflation is now regarded as part of the standard cosmological model because none of the other solutions match observational data to a better extent.
  12. Sep 20, 2012 #11
    It's always useful to come up with a list of alternative explanations and come up with the reason why they didn't work. The two that I know of off hand are slow growth models and variable light speed models.

    One problem is that people argue about something, come up with a conclusion, forget why people came up with the conclusion, and argue about it again.
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