The beginning is the point at which there is no point before.Please define “beginning,” then. For I had understood you using it to mean that there was a point when the Universe first existed in time and space. As a definition, the Universe is time and space. So I conclude the Universe does not exist necessarily.
The universe could not exist always. There is argument for that: It would take infinity to reach infinite past from now, which is impossible through finite waiting, hence the opposite also is impossible.In other words, perhaps it is correct to say that the Universe has always existed in time – for the very definition of the Universe includes time.
I don’t understand what you are trying to say here.But there are good reasons to think the “ultimate reality” is not within time, for the past cannot be infinite.
I disagree, because I believe that you can set up a 1-1 correspondence between time and the real line. for example, the year 2016 corresponds to the point 2016 on the real line. We are now at 2016, but there has been a time when the present was at 1054, etc.Not possible.
An infinite time period, by definition, cannot end.
Yet, if the past is infinite, then the time period from “before now” to “now” is an infinite time period… which just ended.
Sure, but what you’re proposing is that there is no 0-time (an infinite past means no beginning).I disagree, because I believe that you can set up a 1-1 correspondence between time and the real line. for example, the year 2016 corresponds to the point 2016 on the real line. We are now at 2016, but there has been a time when the present was at 1054, etc.
I realize that this may be more than you’re prepared to wrap your head around, but let’s think outside the box for a second. You’re assuming that the past is fixed, and the future isn’t. But let’s suppose for the sake of argument that neither of them is any more fixed than the other, and the only thing that’s truly fixed, is the present. In which case the state of the past and the state of future may be fixed only in-so-far as those states are dictated by the state of the present. Rather than reality having its origin in the past and then proceeding endlessly forward through the present, and into the future, reality may instead have its origin in the present, and then radiate outward, creating what you perceive to be a fixed past and a potential future.But how could an intimate past be possible? Besides, science points to the beginning of our Universe, which is the only physical reality we can observe, anyway.
An infinite future is possible precisely because we assume a beginning.
Condescending tone aside, I don’t think what you’re saying is too hard to understand. The problem people seem to be having with it, is that there simply isn’t any reason to believe it’s true.I realize that this may be more than you’re prepared to wrap your head around, but let’s think outside the box for a second.
Then go ahead and un-assassinate Lincoln.You’re assuming that the past is fixed, and the future isn’t. But let’s suppose for the sake of argument that neither of them is any more fixed than the other, and the only thing that’s truly fixed, is the present.
More like there’s nothing to say that it is.If this is the case, and there’s nothing to say that it isn’t,
Other than the fact that physics tells us that cause and effect works equally well both forwards and backwards in time.The problem people seem to be having with it, is that there simply isn’t any reason to believe it’s true.
More like there’s nothing to say that it is.
Knowledge of the assassination of Lincoln is part of the present, therefore “un-assassinating Lincoln” would be inconsistent with the present. Both the past and the future will always be consistent with the present…Then go ahead and un-assassinate Lincoln.
Yes.Other than the fact that physics tells us that cause and effect works equally well both forwards and backwards in time.
No.Meaning that the present influences the past as well as the future.
Are you arguing, then, for an equally **fixed **past and future?Knowledge of the assassination of Lincoln is part of the present, therefore “un-assassinating Lincoln” would be inconsistent with the present. Both the past and the future will always be consistent with the present…
Not true, because the real line has a zero point.Sure, but what you’re proposing is that there is no 0-time (an infinite past means no beginning).
Where are you starting from? If you are starting from 2000 BC, it would take 4016 years.So how many years would it have taken to get to “now” ?
That is why time travel to the past is impossible. You could go back and kill Lincoln’s assassin one year before the assumed date of the assassination.Knowledge of the assassination of Lincoln is part of the present, therefore “un-assassinating Lincoln” would be inconsistent with the present.
What is the duration of the time period that lasted from “before now” to “now” ?Where are you starting from?
Yes, assuming that there was only one Big Bang, that is about right. However, there are other theories, such as the cyclical theory of the universe which posits a continuous recycling of universes from one Big Bang to one Big Crunch, to another BB to another BC, etc. With the cyclic theory there is no fixed beginning. There is no starting point, which is similar to what you have on the real line. And yes, you are still able to get from any point in the past (negative values on the real line) to a present point (say 2016) on the real line. Further, the whole real line can be put into 1-1 correspondence with the finite interval ( -1, 1) ={x: -1<x<1}. and this interval is seen to have no starting point and no point at infinity and you can always get from one point to another. There are different ways of setting up this 1-1 correspondence between the real line and the interval ( -1, 1).What is the duration of the time period that lasted from “before now” to “now” ?
I would say it’s probably 13.7 billion years. How many do you say?
Just to clarify, it has been experimentally demonstrated that the present can apparently affect the past. Granted, the extent to which this phenomenon holds true is as yet unknown. So to assert, as I have, that the present creates the past is indeed highly speculative. But it is none-the-less, possible. Which was my point. You can’t definitively say that an infinite past is impossible. You may deem it to be unlikely, but you can’t categorically rule it out.Not at all.
It’s true that the physical processes would still add up the right way, if you “ran the tape” backwards. But that doesn’t mean that’s how it actually happened.
That’s the basic argument. That the information available in the present dictates the state of both the past and the future, and that neither are fixed beyond the point that the present forces them to be fixed. The basic premise is, that cause and effect don’t begin in the past and and travel forward, but rather begin in the present and radiate outward, creating both the past and the future. There’s no end, in either direction.Are you arguing, then, for an equally **fixed **past and future?
I doubt that what has already happened in the past can be changed by an action in the present.Just to clarify, it has been experimentally demonstrated that the present can apparently affect the past…
Except the finite interval** does** have a starting point.Further, the whole real line can be put into 1-1 correspondence with the finite interval ( -1, 1) ={x: -1<x<1}. and this interval is seen to have no starting point and no point at infinity and you can always get from one point to another. There are different ways of setting up this 1-1 correspondence between the real line and the interval ( -1, 1).
What is the starting point in the interval: {x: -1<x<1} or (-1,1)?Except the finite interval** does** have a starting point.
What is the smallest possible unit of time?And for that explanation to work, you’d have to assume that a finite interval of time is infinitely divisible, which it isn’t. There is a smallest possible unit of time.
You don’t have to assume infinite divisibility for a 1-1 correspondence to work. One example of a 1-1 correspondence between the interval (-1,1)and the whole real line is:And for that explanation to work, you’d have to assume that a finite interval of time is infinitely divisible, which it isn’t. There is a smallest possible unit of time.
TomYou don’t have to assume infinite divisibility for a 1-1 correspondence to work. One example of a 1-1 correspondence between the interval (-1,1)and the whole real line is:
F(x) = tan (x*pi/2)
Of course, Arctan is going to give a correspondence between the real line and the given interval.
A Planck time.What is the smallest possible unit of time?
Negative one.What is the starting point in the interval: {x: -1<x<1} or (-1,1)?
Yes you do. The real number line has infinite points on it. If you want a one-to-one match with an interval, that interval would need to contain an infinite number of points.You don’t have to assume infinite divisibility for a 1-1 correspondence to work.