This has most likely been mentioned before and if so I apologise, I have seen a few similar discussions though didn't really see any answers that I was able to understand/accept.

The problem is if there is an infinite amount of time in the past then how is there a present? (I know there can be issues with defining present as well but let's generalise it.)

I got told this is similar to Zeno's paradox so just wondering if anyone can show me the similarities and logical arguments against it (in layman terms lol)

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the present is the changeover from one configuration of the universe to the next. it is the only moment which truly exists. past and future are just potentials.sure we have memories and ideas of what is going to occur but they are not happening. say these words: "this is not real it is only a memory." by the time you finish it will be true. the moment you expierience or remember from that is important. that exists. make a decision, look up. you can ponder all day but, until you expierience looking up, its just a potential, not real. i dont know about xeno or whatever but this is how time seems to function.

This has most likely been mentioned before and if so I apologise, I have seen a few similar discussions though didn't really see any answers that I was able to understand/accept.

The problem is if there is an infinite amount of time in the past then how is there a present? (I know there can be issues with defining present as well but let's generalise it.)

I got told this is similar to Zeno's paradox so just wondering if anyone can show me the similarities and logical arguments against it (in layman terms lol)

The future is always in front, yet it is always the last to arrive. This resolves the mooted existence of an infinite past with a problematic present.

disregardthat
This has most likely been mentioned before and if so I apologise, I have seen a few similar discussions though didn't really see any answers that I was able to understand/accept.

The problem is if there is an infinite amount of time in the past then how is there a present? (I know there can be issues with defining present as well but let's generalise it.)

I got told this is similar to Zeno's paradox so just wondering if anyone can show me the similarities and logical arguments against it (in layman terms lol)

I personally don't see the similarities to Zeno's paradoxes. I find the argument faulty, a bit like asking why 0 on the number lines exists even though the number line is infinitely long.

apeiron
Gold Member
The problem is if there is an infinite amount of time in the past then how is there a present? (I know there can be issues with defining present as well but let's generalise it.)
Sounds like you want to discuss this cosmological proof of god's creation of the universe?

http://en.wikipedia.org/wiki/The_Kalam_Cosmological_Argument_(book [Broken])

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alt
Gold Member
Sounds like you want to discuss this cosmological proof of god's creation of the universe?

http://en.wikipedia.org/wiki/The_Kalam_Cosmological_Argument_(book [Broken])
Interesting book, though from the summary points, and without having read it, it doesn't seem to take us past any existing impasse on these matters. To quote part of the Wiki article;

The basic argument
1.Whatever begins to exist, has a cause of its existence (i.e. something has caused it to start existing).
2.The universe began to exist. i.e., the temporal regress of events is finite.
3.Therefore, the universe has a cause.

Following Al-Ghāzāli, Craig argues that this cause must be a personal will.

My underlined .. it seems most cosmological arguments reduce to this. The first cause; God, or Big bang .. personally, I'm not to sure about either.

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apeiron
Gold Member
Interesting book, though from the summary points, and without having read it, it doesn't seem to take us past any existing impasse on these matters.
I've said often enough how some philosophers get round this impasse - vague beginnings and final causes.

But the thread seems to be about the validity of a Zeno paradox here, and the argument that the paradox means the past cannot be infinite, therefore it must be finite, therefore....etc.

There are good arguments against the validity of the Zeno paradox itself, so whether time is finite or infinite is moot on that score.

See for instance...
http://www.godcontention.org/index.php?qid=96

Sounds like you want to discuss this cosmological proof of god's creation of the universe?

http://en.wikipedia.org/wiki/The_Kalam_Cosmological_Argument_(book [Broken])
No, I don't really care for any god arguments it was just something I didn't really understand.

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The basic argument
1.Whatever begins to exist, has a cause of its existence (i.e. something has caused it to start existing).
2.The universe began to exist. i.e., the temporal regress of events is finite.
3.Therefore, the universe has a cause.

I don't see how this would prove God.

The Universe must have some sort of "cause". But, it could simply be part of a larger Multiverse, that gave "birth" to it. Then you might ask, where did the Multiverse come from? So, the God question simply gets pushed back a step.

I think more clear here is the ridiculous infinite regression one can get stuck in when analyzing in a "cause and effect" sort of way. What created the Universe? Well, branes "created" the Universe (says the M-Theory cosmologist). But, where did the branes come from? Then, what created the something that created the branes, ad nauseum.

I think this is a hint that thinking linear in time is, at some point, self defeating.

I don't see how this would prove God.
You forgot to say man.
What?
I said you forgot to say man.
You should have said-
I don't see how this would prove God, man.

Style's the thing, man.

I think I know what you mean with Zeno's paradoxes. You can divide a interval of time to an infinite amount, it is similar to the analogy that there will be an infinite amount of steps you have to take to walk across a room if the amount of distance your walking is half of what is left.
So, to demostrate this notion from what I read in a calculus book(which is also where I read Zeno's paradox). Let x be the amount of time one perceives a constant amount of time.
So, we take the Limit as x --> infinity of (x/(constant interval of time)) = infinity
We can examine that anything less of infinity would give us a figure that tells us the multiples of time the being feels regarding the (constant interval of time).

And to finally answer your question...I'm not sure...time still passes for us regardless. It could be infinite for the being that has his perception of time that continuously increases so that he will fall deeper and deeper into an eternity of time...

The problem is if there is an infinite amount of time in the past then how is there a present? (I know there can be issues with defining present as well but let's generalise it.)
I don't really see a problem. I would think that if there was an infinite amount of time in the past, then that just means the universe had no beginning and we are currently living in the "present".

Hi Assist. You will find Peter Lynds has written on Zeno's paradoxes, singularities and 'infinite time' (among other things). Take a look at http://www.peterlynds.net.nz/papers.html [Broken]. Interesting reading. Accusations have been made that he is not a real person, but whoever wrote those papers is certainly a deep thinker.
F-MA=0.

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time is just an illusion created by our brains. it doesnt really exist

time is just an illusion created by our brains. it doesnt really exist

Time is duration an outward motion of matter called dilation, it is not an illusion. Time is relative motion as counted or measured by each observers clock and space is the illusion for it is nothing more than relative time between events as seen by each observer. Matter is what we see in each of our futures but mass is the connective tissue centered moment to moment within our past. Our consciousnesses keeping up with the speed of light is that which gives each of us the illusion of a static state called the present but only with math can you make time stand still, even then you are only representing a moment of time. How long was the duration before the motion that started our universe and how long will the duration go on after, how could you know other than as a infinite time?

if there is an infinite amount of time in the past then how is there a present
Who said that there is an infinite amount of time in the past?

Assuming that there were... than perhaps time is an artificial construction of the human mind which seeks to measure change. In other words, there was no point in "time" when the past existed. Maybe only the present "exists" in a physically-meaningful sense.

We get the same paradox if we ask how we can be sitting on zero non-physical unicorns, if there are infinitely many non-physical unicorns.

The problem is if there is an infinite amount of time in the past then how is there a present? (I know there can be issues with defining present as well but let's generalise it.)
Maybe if you lived in the fourth dimention. But, you can at least specify what you are saying with some philosophical theory, such as eternalism. And then counter it with presentism. Back each theory up with some relevant findings and we can have a great debate!

We get the same paradox if we ask how we can be sitting on zero non-physical unicorns, if there are infinitely many non-physical unicorns.

Try this thought experiment, think back to big bang, but instead of an outside view of a small space, think of an inside view of a large space about the same as we see today as if Planck's scale were truly relative. It began with motion. No motion = no time. When a “Single Something” separated creating motion that was the beginning of time.

Let that “ Single Something” = S

S = No motion = No Speed = No Mc^2. = No Energy.

S is outside the bun.

It is not imaginary.

The original motion, like all other motion cannot be duplicated, so S is not Divine, yet S can be moved.

Wierd, huh?

Can we please have a discussion about http://en.wikipedia.org/wiki/Eternalism_%28philosophy_of_time%29" [Broken] (otherwise known as eternalism).

"people pass each other on the street; and according to one of the two people, an Andromedean space fleet has already set off on its journey, while to the other, the decision as to whether or not the journey will actually take place has not yet been made. How can there still be some uncertainty as to the outcome of that decision? If to either person the decision has already been made, then surely there cannot be any uncertainty. The launching of the space fleet is an inevitability. In fact neither of the people can yet know of the launching of the space fleet. They can know only later, when telescopic observations from earth reveal that the fleet is indeed on its way. Then they can hark back to that chance encounter, and come to the conclusion that at that time, according to one of them, the decision lay in the uncertain future, while to the other, it lay in the certain past. Was there then any uncertainty about that future? Or was the future of both people already 'fixed'?"

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SixNein
Gold Member
I think I know what you mean with Zeno's paradoxes. You can divide a interval of time to an infinite amount, it is similar to the analogy that there will be an infinite amount of steps you have to take to walk across a room if the amount of distance your walking is half of what is left.
So, to demostrate this notion from what I read in a calculus book(which is also where I read Zeno's paradox). Let x be the amount of time one perceives a constant amount of time.
So, we take the Limit as x --> infinity of (x/(constant interval of time)) = infinity
We can examine that anything less of infinity would give us a figure that tells us the multiples of time the being feels regarding the (constant interval of time).

And to finally answer your question...I'm not sure...time still passes for us regardless. It could be infinite for the being that has his perception of time that continuously increases so that he will fall deeper and deeper into an eternity of time...
In zeno's Achilles vs the turtle paradox, the solution is to realize that the steps make up a series. When the limit of the series is taken, it will converge into a finite distance; therefore, if Achilles is running at a constant speed, he will catch the turtle in a finite time.

disregardthat
In zeno's Achilles vs the turtle paradox, the solution is to realize that the steps make up a series. When the limit of the series is taken, it will converge into a finite distance; therefore, if Achilles is running at a constant speed, he will catch the turtle in a finite time.
The core of the problem is whether and how it makes sense to do an infinite amount of tasks. The series of lengths does converge, but why would one say that the limit is the "total length"? (It seems obvious of course, but why?)

The main point here is that there has been a decision; we have decided that the "total length" of an infinite number or converging lengths is excactly the limit. We have given meaning to the notion of the total length of an infinite number of lengths.

This could of course have been different. We might as well say that the "total length" of an infinite number of lengths is 0. This would have been a different decision, but doesn't contradict anything prior to it. We just didn't know beforehand what to make of the total length. My point is that Zeno's paradox is not solved by referring to convergence, as this is - in a naive way - an arbitrary solution.

The notion of total length is however decided upon and incorporated into our logical machinery (to the point of which we take no notice...), but it is important to be aware of that there has been decisions all along.

In my opinion, the paradox is just that we arrive upon a physical situation for which we have no answer. There are ways to an answer that would seem more "appropriate" than others, but there is no logical reason for deciding upon one or another.

I must stress that this paradox is purely a logical one. It has nothing to do with the physics to it, nor the physical counterpart we would associate the situation with (though it is relevant when it comes to the point of deciding one way or another).

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SixNein
Gold Member
The core of the problem is whether and how it makes sense to do an infinite amount of tasks. The series of lengths does converge, but why would one say that the limit is the "total length"? (It seems obvious of course, but why?)
Since the limit of the sum represents the total area under the curve, the total length is the limit.

Although a task can be broken up into an infinite number of steps, it may also be possible to accomplished in a finite number of steps.

The main point here is that there has been a decision; we have decided that the "total length" of an infinite number or converging lengths is excactly the limit. We have given meaning to the notion of the total length of an infinite number of lengths.

We have determined that a infinite sequence of measurements, when summed, can be equal to a finite number.

This could of course have been different. We might as well say that the "total length" of an infinite number of lengths is 0. This would have been a different decision, but doesn't contradict anything prior to it. We just didn't know beforehand what to make of the total length. My point is that Zeno's paradox is not solved by referring to convergence, as this is - in a naive way - an arbitrary solution.
The assumption I have made is Achilles' decent upon the turtle is such that it causes the series to converge.

The notion of total length is however decided upon and incorporated into our logical machinery, but it is important to be aware of that there has been decisions all along.

In my opinion, the paradox is just that we arrive upon a physical situation for which we have no answer. There are ways to an answer that would seem more "appropriate" than others, but there is no logical reason for deciding upon one or another.

I must stress that this paradox is purely a logical one. It has nothing to do with the physics to it, nor the physical counterpart we would associate the situation with.
Here is a rough introduction to the mathematical concept being used:
http://en.wikipedia.org/wiki/Riemann_sum

disregardthat