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Time Likely To End Within Earth's Lifespan, Say Physicists

technologyreview.com

11–20 of 64 posts

Re: Time Likely To End Within Earth's Lifespan, Say Physicists

#13

This theory is well across the line from science and into religion. How is this: "we'll run headlong into this catastrophe before we can observe its effects on anything else." any different than this: "But of that day and hour knows no man, no, not the angels of heaven, but my Father only." http://bible.cc/matthew/24-36.htm

The difference is "Father knows".

Re: Time Likely To End Within Earth's Lifespan, Say Physicists

#14
post #6

"If the universe lasts forever, then any event that can happen, will happen, no matter how unlikely." That's just plain mathematically wrong. There are many kinds of infinity ( http://en.wikipedia.org/wiki/Aleph_number ), and the set of all possible events has a much, much higher cardinality than an infinite axis of time. This is similar to saying that, since the set of integers is infinite, it must contain Pi.

> This is similar to saying that, since the set of integers is infinite, it must contain Pi.

Not exactly. Pi has no chance of occurring in an infinite set of integers.

Re: Time Likely To End Within Earth's Lifespan, Say Physicists

#15
post #6

"If the universe lasts forever, then any event that can happen, will happen, no matter how unlikely." That's just plain mathematically wrong. There are many kinds of infinity ( http://en.wikipedia.org/wiki/Aleph_number ), and the set of all possible events has a much, much higher cardinality than an infinite axis of time. This is similar to saying that, since the set of integers is infinite, it must contain Pi.

Well, there IS an integer that contains all the digits of Pi

3141592...

Re: Time Likely To End Within Earth's Lifespan, Say Physicists

#17

From the sounds of it, this is a far from accepted idea that's just now coming out in like it's first paper or something, so don't start planning your End of Time Party. There's still a lot of verification and research and math between this being published and it becoming the consensus among physicists.

> don't start planning your End of Time Party

Rats, there goes my idea for building a Restaurant at the End of the Universe!

Re: Time Likely To End Within Earth's Lifespan, Say Physicists

#18
post #6

"If the universe lasts forever, then any event that can happen, will happen, no matter how unlikely." That's just plain mathematically wrong. There are many kinds of infinity ( http://en.wikipedia.org/wiki/Aleph_number ), and the set of all possible events has a much, much higher cardinality than an infinite axis of time. This is similar to saying that, since the set of integers is infinite, it must contain Pi.

Well, there IS an integer that contains all the digits of Pi 3141592...

No, that "integer" would need to have an infinite number of digits, and no integer has an infinite number of digits.

Re: Time Likely To End Within Earth's Lifespan, Say Physicists

#20
post #6

"If the universe lasts forever, then any event that can happen, will happen, no matter how unlikely." That's just plain mathematically wrong. There are many kinds of infinity ( http://en.wikipedia.org/wiki/Aleph_number ), and the set of all possible events has a much, much higher cardinality than an infinite axis of time. This is similar to saying that, since the set of integers is infinite, it must contain Pi.

Their statement makes sense: If you have a non zero probability of something happening, say P, and N times that it could happen, then you would expect it to happen about P * N times. Lets let E = P * N. Now as N goes to infinity the number of times you expect it to happen does as well. Both go to a countable infinity (Aleph 0 as you linked) which is a problem when it comes back to defining P. Normally we would say P = E / N but this doesn't make sense when E and N are both the same 'size' of infinity.
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