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Thread: Stephen Hawking last work

  1. #31
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    Quote Originally Posted by Sinbad View Post
    So what is different in our lifetime than hundreds or thousands of years ago.
    Also all scenarios mentioned point to thinks atleast billions s of years away except for vacuum collapse, is that what is meant by anytime or is there other things that aren’t mentioned.
    I'm not sure what you are asking. Most scenarios for the end of the universe involve things like all the stars running out of fuel so the universe become dark and cold. This will require an unimaginably long time.

    Vacuum decay could happen anytime and therefore is extremely unlikely to happen soon.

    So, whatever happens, it will be a long time in the future (and I mean a lot further away than Sunday afternoon).

  2. #32
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    That’s what I mean she talks of 5 scenarios
    I know the 4 main ones are predicted a long ways into the future so is the one she mentions anytime vacuum collapse or is there othe scenarios

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    About the universe, does this help? I know that I will be dead in 50 years. But I also know there is a small chance I will be struck by a meteorite ten minutes from now. Does that mean Iím likely to get struck by one? Not at all. We believe that the universe will end in billions or trillions of years. But who knows, it could end ten minutes from now, if something happens that we donít understand.


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    But why are odds of this happening better now that in the past?

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    Quote Originally Posted by Sinbad View Post
    That’s what I mean she talks of 5 scenarios
    I know the 4 main ones are predicted a long ways into the future so is the one she mentions anytime vacuum collapse or is there othe scenarios
    Yes, vacuum decay could happen any time.

    Any time means it is extremely unlikely to happen soon. It means it is extremely unlikely to happen in your lifetime. It is extremely unlikely to happen in the lifetime of the Sun (about another 5 billion years). So probably not worth worrying about.

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    Quote Originally Posted by Sinbad View Post
    But why are odds of this happening better now that in the past?
    They are not. Why do you think that?

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    Quote Originally Posted by Sinbad View Post
    But why are odds of this happening better now that in the past?
    Sinbad: "When will the world end?"

    Everyone on the planet: "Not for billions and billions and billions of years"

    Sindbad: "Tomorrow?"

    Everyone on the planet: "No, not for billions and billions and billions of years"

    Sinbad: "But why is it more likely to be tomorrow?"

  8. #38
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    Not sure just the feeling I got.

    So basically on the book the anytime scenario is vacuum collapse which I believe she herself has an article where she states it is far in the future.

    Or is there another scenario I am missing?

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    Quote Originally Posted by Sinbad View Post
    Not sure just the feeling I got.
    And as has been repeatedly explained, you "feeling" is not based on anything

    So basically on the book thebanytime scenario is vacuum collapse which I believe she herself has an article where she states it is far in the future.

    Or is there another scenario I am missing?
    I think that is right. Vacuum decay is the only one that could happen "any time" (ie. most likely in the far distant [billions of years] future, if at all).

  10. #40
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    I am not sure what I understand anymore about all this
    Everyone says it’s far far away, book says anytime and I am not sure what scenarios mean anytime and not sure anymore what to think

    I am sorry I feel like a big idiot right now
    Last edited by Sinbad; 2020-Jan-24 at 01:00 AM.

  11. #41
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    There's a misunderstanding, I think, because the phrase "any time" is often (mis)used to mean "soon": "Professor, this reactor could blow at any time!" "My god! Evacuate the building!"

    Whereas "any time" relative to the entire lifetime of the Universe means "essentially, forget it; not going to happen".

    Grant Hutchison

  12. #42
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    To me any moment means within short period of time so the comment of can happen any moment Means shortly
    I am not sure how to others this means billions of years
    Last edited by Sinbad; 2020-Jan-24 at 01:42 AM.

  13. #43
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    Quote Originally Posted by Sinbad View Post
    To me any moment means within short period of time so the comment of can happen any moment Means shortly
    You're misunderstanding the term, then. Nobody is using it in the sense of "soon," which is also a valid meaning. We are using it in the literal sense of, it could happen at any point in the billions of years since the Universe has existed all the way to the billions of years into the future that we believe the Universe will exist for. It's not more likely to happen tomorrow then at any other day within those billions of years.
    As above, so below

  14. #44
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    Does any moment not mean soon ? Her book states her professor told her any moment. I find nothing about her findings contradicting that.

    Not sure how any moment means nothing other than shortly and means billions of years from now.
    Last edited by Sinbad; 2020-Jan-24 at 01:57 AM.

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    Quote Originally Posted by Sinbad View Post
    To me any moment means within short period of time so the comment of can happen any moment Means shortly
    But as was said, that’s not how we are using the term. It’s an idea suggested by physics that can’t be ruled out (for now, at least) but there is no reason to assume it is true, either. It’s a possibility. And there is absolutely no reason to think it would be imminent if it were true. Look, the universe has been puttering along for nearly 14 billion years. Just because somebody comes up with an idea today, after 14 billion years, doesn’t mean the idea will be validated the next day.

    I am not sure how to others this means billions of years
    In the most widely accepted current view of the future, the universe slowly gets colder and darker. In that view, a billion years is a blip compared to the many years of changing events of the universe. In 5 billion years or so, when our sun goes red giant, the universe is expected to be not all that different from today. In a trillion years, star production would be way down, so not many high mass stars would exist, mostly low mass stars. It would be different, but something like humans could probably survive then. In a quadrillion years, red dwarf stars would be rare, but something like humans with advanced technology could probably survive. Other kinds of life could perhaps survive on proposed extremely long lived but cool stars (lots of heavy elements in a star could allow for very long lived stars with a cool surface.

    And that would all be a small part of the future.

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  16. #46
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    Quote Originally Posted by Sinbad View Post
    Does any moment not mean soon ? Her book states her professor told her any moment. I find nothing about her findings contradicting that.

    Not sure how any moment means nothing other than shortly and means billions of years from now.
    I think this has been answered more than once. You seem to be very persistently pursuing the idea that the universe or the Earth will be destroyed very soon. I donít know how many more ways we can say that there is no good evidence for that. I donít know why you are so persistent, but if you are worried enough about it that it is affecting your everyday life, perhaps you should talk to someone about it. We can only talk about the science here, and as should be clear, we are not worried about it.

    "The problem with quotes on the Internet is that it is hard to verify their authenticity." ó Abraham Lincoln

    I say there is an invisible elf in my backyard. How do you prove that I am wrong?

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  17. #47
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    I am trying to grasp it but the words any moment ring out as shortly,

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    Quote Originally Posted by Sinbad View Post
    I am trying to grasp it but the words any moment ring out as shortly,
    The odds are immensely low that the Universe will end within any humanly comprehensible period of time. Certainly not within the lifespan of the Sun, which is about five or six billion years in the future, long, long after everyone alive today is dead and dust.

    The end of existence is literally, the least likely thing to have to worry about. The Universe is the safest thing there is.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

  19. #49
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    Quote Originally Posted by Sinbad View Post
    To me any moment means within short period of time so the comment of can happen any moment Means shortly
    I am not sure how to others this means billions of years
    "Any moment [now]" might be used to mean "soon".

    But "at any time" means, literally, any time at all in the next billion, billion, billion years (or the last 13.8 billion years). Not necessarily soon.

    For example, it could happen today (Friday). But it is equally likely to happen next Friday (or any day in between). And it is equally likely to happen the Friday after that. It is equally likely to happen on any Friday in the next year, or the next billion years.

    But there are 365 billion more Fridays in the next billion years, so it is 365 billion times more likely to happen on one of those than today (or next Friday or any other Friday).
    Last edited by Strange; 2020-Jan-24 at 09:28 AM.

  20. #50
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    Quote Originally Posted by Strange View Post
    "Any moment [now]" might be used to mean "soon".

    But "at any time" means, literally, any time at all in the next billion, billion, billion years (or the last 13.8 billion years). Not necessarily soon.

    For example, it could happen today (Friday). But it is equally likely to happen next Friday (or any day in between). And it is equally likely to happen the Friday after that. It is equally likely to happen on any Friday in the next year, or the next billion years.

    But there are 365 billion more Fridays in the next billion years, so it is 365 billion times more likely to happen on one of those than today (or next Friday or any other Friday).

    And that is my point it says Any moment

  21. #51
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    Quote Originally Posted by Sinbad View Post
    And that is my point it says Any moment
    ANY moment.

    That could be the next second. Or the one after that. Or any second in the next billions years. There are 30 million billion seconds in the next billion years. It is equally likely to happen in any of those.

    So it is very unlikely to happen in the next second.

    *pause*

    See, it didn't.

    It is 30 quadrillion times more likely to happen in the future.

  22. #52
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    Quote Originally Posted by Sinbad View Post
    And that is my point it says Any moment
    Any moment, in this context, means it has a one in 1,000,000,000,000,000,000,000* chance of happening in each second. Much better odds that you'd be struck by lightning while being eaten by a shark on fire in a tornado.

    ADDED:

    *,000,000,000,000,000,000,000,000,000,000,000,000, 000,000,000,000,000,000,000,000,000,000,000,000,00 0,000,000,000
    Last edited by Noclevername; 2020-Jan-24 at 09:56 AM.
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  23. #53
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    Quote Originally Posted by Sinbad View Post
    ... I was understanding he has never been proven wrong?
    Wow! What a status this man must have that instead of people struggling to demonstrate that he is right, he is assumed right unless people prove him wrong! (I am using irony, he doesn't have that status).
    Vacuum decay might happen, but it is not a demonstrated part of mainstream science. It is on the fringe, and could only be true if a certain range of models we haven't fully done the math for, and which are so far untestable can be applied. We DO NOT KNOW if Vacuum Decay would/could ever happen. Models that do suggest it seem to favor that it only happens after all the stars have finished fusing, all the white dwarfs have cooled to near absolute zero, all the black holes have evaporated (which itself hasn't ever been observed, or proven to be possible, but is connected to the same models) completely. and the dark energy has separated everything too far for remaining atoms to collide. IF one of those models is actually models the universe, then the "at any time" is probably a time between 10^80 and 10^10^1000 years from now. It is NOT soon, or before the Sun is a red giant, or anytime you can imagine. It is also very possible that those models do not model the universe well enough to be right, and vacuum decay will never happen.
    Last edited by antoniseb; 2020-Jan-24 at 12:05 PM. Reason: typo fixed
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  24. #54
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    Here is my confusion

    The quote from the amazon prelogue of the book is as follows

    [QUOTE][/[Dr. Katie Mack has been contemplating these questions since she was eighteen, when her astronomy professor first informed her the universe could end at any moment, setting her on the path toward theoretical astrophysics.

    So what was the scenario he was speaking of? The only one I have ever heard of is Vacuum collapse theory, what else is there

    And why would the term at any moment be used?

  25. #55
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    Quote Originally Posted by Sinbad View Post
    ... And why would the term at any moment be used?
    To sell books.
    Forming opinions as we speak

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    The book wasn’t written 20 years ago?

  27. #57
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    Quote Originally Posted by Sinbad View Post
    The book wasn’t written 20 years ago?
    Sorry to say this, but kind of repeating what Van Rjin said earlier, I really think you need to talk to someone who deals with anxiety issues. Obviously our explanations are not helping you to overcome the problems that you see. We're really trying to help, but somehow it doesn't seem to get through, and I suspect there must be some reason for that.
    As above, so below

  28. #58
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    Quote Originally Posted by Sinbad View Post
    The book wasn’t written 20 years ago?
    But it is being promoted now.

  29. #59
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    As far as I can see, Katie Mack's The End Of Everything hasn't been published yet. So we have no way of knowing who this professor was or why he said what he said.
    What we can see is that some editions of the book are subtitled "(Astrophysically Speaking)" and some are subtitled "Five Ways The Universe Might End (But Don't Panic)".
    So the subtitles are telling you exactly what everyone here is telling you. You are pretty obviously misunderstanding the use of the phrase "at any moment" in this context. So I suggest you also start taking on board "astrophysically speaking" and "don't panic", given that you're trying to glean meaning from the cover of an unpublished book.

    Grant Hutchison

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    May be worth noting that as well as being an astrophysicist, Dr Mack is also a science communicator. So a lot of her statements for public (rather than professional) consumption are designed to be catchy, entertaining, and maybe even a bit scary (superficially). But that doesn't mean that there is anything to worry about.

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