How long is the present?

Felix Da Housecat · 2 Nov 2006 at 17:22

The answer is...... Less than you think

Podfather · 2 Nov 2006 at 18:07

The future does exist. The next generation is the future and we are the present if you look at in that way. The past are the deceased and people who are on there last legs. The present is right now, the past is before and the future is in front of us.

Psyk · 2 Nov 2006 at 18:18

sendos said:
there has to be a smallest unit of time, just like there has to be a smallest unit of distance that is indivisble. think its called zenos paradox, if there wasnt a smallest unit of distance and you tried to run 100m youd never be able to finish the race because everytime your tried to cross the finish line, the distnace you would need to travel across would just become smaller and smaller and smaller and you'd never reach your destination. just like time you'd never be able to reach you first birthday infact you couldnt even exist if there wasnt a definite present and a definite past.

Hmm I don't quite get that. We all know there's an infinite amount of numbers between 0 and 10 but if you take steps of 1 then you'll reach 10 in 10 steps. Seems kind of obvious though, maybe I'm just not understanding your point.

Sweetloaf · 2 Nov 2006 at 18:48

Psyk said:
Hmm I don't quite get that. We all know there's an infinite amount of numbers between 0 and 10 but if you take steps of 1 then you'll reach 10 in 10 steps. Seems kind of obvious though, maybe I'm just not understanding your point.

Agreed, It makes the assumption that you are halving the distance with each step. Poppycock I say

Ricochet J · 2 Nov 2006 at 19:11

Johanson said:
Planck time!

Can't touch this!

titaniumx3 · 2 Nov 2006 at 19:23

Arcade Fire said:
A question:

As time passes, you change as a person. You change from second to second, and over time those small changes build up to much greater changes. In ten years you could be a completely different person to the person that you are today. In fact, the 'you' of today might hate the 'you' that you're going to be in ten or twenty years time.

Given that, why do we bother doing things that are of no benefit to our present selves, but that are only going to benefit us in the remote future? Why do we sacrifice our own interests to benefit some unknown stranger, who we might very well hate if we met them!

I'm not asking this as a question demanding of an answer, but rather just to stimulate thinking.

If we were only interested in the present we would all just sit still, static forever. To me the constantly changing state of the three dimensional world is a limited form of time travel.

RetiredGreyFox · 2 Nov 2006 at 19:26

Consider the sandwich.

The present is looking at the sandwich and the future is you thinking about cutting it in half and when you cut it in half it is now the past.

Vonhelmet · 2 Nov 2006 at 19:31

Time is an illusion. Lunchtime doubly so.

Efour · 2 Nov 2006 at 19:31

dmpoole said:
Consider the sandwich.

The present is looking at the sandwich and the future is you thinking about cutting it in half and when you cut it in half it is now the past.

whats in the sandwhich?? mmmmmmm

RetiredGreyFox · 2 Nov 2006 at 19:34

Efour2 said:
whats in the sandwhich?? mmmmmmm

Forgot because it was in the past.

Rich_L · 2 Nov 2006 at 19:47

The past is history, the future's a mystery....ok ok I'll stop now

It's the good old problem of attempting to apply a discrete measuring system to something of a continuous nature!

There was a roughly similar discussion about when, exactly, is midday..as soon as your clock goes from 11:59 to 12:00 you are an infitessimal amount of time past midday, so when exactly is midday?

I figure that you approach 'now' when the difference between the future and the past tends to zero...so 'now' is much like zero in mathematics, a convenient label for the mid-point between positive and negative time.

locutus12 · 2 Nov 2006 at 20:47

technically the present doesnt exist, there is only the past and the future, for there to be a present there would have to be an amount of future time that stopped for a brief ammount of given time creating "present time" before becomming past.

what we percieve to be present is just that... perception... nothing more

Zogger · 2 Nov 2006 at 21:26

Psyk said:
Hmm I don't quite get that. We all know there's an infinite amount of numbers between 0 and 10 but if you take steps of 1 then you'll reach 10 in 10 steps. Seems kind of obvious though, maybe I'm just not understanding your point.

but how do you take a step of 1 without stepping through every number in-between?

Freefaller · 2 Nov 2006 at 22:07

It's about | | <- that long.

Daveyboy · 2 Nov 2006 at 22:11

Johanson said:
Planck time!

Gotta love the Compton wavelength!

Personally I don't believe there is a present, just a swift movement from past to future. We are living in the future and creating the future. If we lived in the "present" nothing would happen at all. Sort of like limbo but without people trying to clamber under broomsticks

Psyk · 2 Nov 2006 at 22:35

Zogger said:
but how do you take a step of 1 without stepping through every number in-between?

By adding one of course

Seriously though, I get what you're saying. But consider some graph of x plotted against y = some function of x. Not really important what function except that it has to be continuous and have a range of all real numbers. Imagine moving at a steady pace along the x axis. Take any value of y and eventually you will get to that value by following the graph along the x axis. There are an infinite amount of points on that graph, there are no discrete steps. But regardless eventually you will reach that y value. It makes no difference that there are an infinite amount of numbers between that value and where you started.

sendos · 2 Nov 2006 at 23:00

Psyk said:
By adding one of course

Seriously though, I get what you're saying. But consider some graph of x plotted against y = some function of x. Not really important what function except that it has to be continuous and have a range of all real numbers. Imagine moving at a steady pace along the x axis. Take any value of y and eventually you will get to that value by following the graph along the x axis. There are an infinite amount of points on that graph, there are no discrete steps. But regardless eventually you will reach that y value. It makes no difference that there are an infinite amount of numbers between that value and where you started.

yes it does thats the point, if there is an infinite amount of numbers between that value then you will never actually reach it. becuase everytime you take another step theres aother hurdle to overcome. hence the word infinity, never ending.

Psyk · 3 Nov 2006 at 00:24

sendos said:
yes it does thats the point, if there is an infinite amount of numbers between that value then you will never actually reach it. becuase everytime you take another step theres aother hurdle to overcome. hence the word infinity, never ending.

But just because there is an infinite amount of numbers between them doesn't mean you'll never reach it. Just look at a graph like I described, it's obvious you can get to that point by following it. So say I'm on the graph y = x^3, starting at the origin and I want to get to 1000 on the y axis. I just follow the line to where x=10 and there I am at y=1000. There's clearly an infinite amount of numbers between 0 and 1000 but I still managed to get there.

When you apply this to a real problem such as running 100m then you can't be exactly certain at what time you reach 100m, but it's pretty damn obvious when you've gone past it.

yer_averagejoe · 3 Nov 2006 at 00:28

not going to bother reading the thread but basically the present is infinetly small and theres no "slice of time". For any scientific or physical worth though, you could define a slice as the plank unit of time, the time taken for a photon to cover the plank length. EXTREMEly small!

Edit: Psyk you're wrong.

Locrian · 3 Nov 2006 at 00:53

I would say that the present is infinitely long since the viewer can never exist in either the past or the future. Since passage of time is merely a recognition of passing events it is unfair to state that the present is only fleeting since it suggests time is stationary where it is infact constantly moving. While the viewer moves with time, time moves with the viewer and thus we are constantly stuck in the void of the present.

There is no such thing as a transition from the future to the present. Since no future event is absolute till it occurs the future is infact an illusion and merely a consequence of the past. Relative to time, the present is eternity. Relative to a perception of time, it is only fleeting.