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Your favourite Paradox

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Reply 40
Original post by Mystic Creature
Everyone must know about the grandfather paradox. I love that one!

It's like this: Just say you could go back in time and kill your grandfather (also works perfectly well for father too actually). If your grandfather dies, then obv you werent born.....MEANING you couldn't have gone back in time to kill your grandfather, MEANING your grandfather actually isnt dead, MEANING you do exist and can go back in time to kill him....and so on!


This is fun: http://youtu.be/UJNhLDwj6kI
Reply 41
Original post by Guru Jason
Surely it depends on what the destination. If your crossing the road with a finite distance then, it will take a long long while but you would eventually get there wouldn't you?


Well, assuming that each step takes the same amount of time, then no. That is if you cross half the road in the first step, the next quarter in the next and the next eighth in the next and so on.

If you move at constant velocity, then you will, after an infinite number of steps. However, an infinite number of steps in this case won't occupy an infinite amount of time.
(edited 11 years ago)
Reply 42
i suppose this is a cliché but if God is good then why does he let people suffer ? e.g. famine, mass poverty, poor health etc
Original post by Mystic Creature
Everyone must know about the grandfather paradox. I love that one!

It's like this: Just say you could go back in time and kill your grandfather (also works perfectly well for father too actually). If your grandfather dies, then obv you werent born.....MEANING you couldn't have gone back in time to kill your grandfather, MEANING your grandfather actually isnt dead, MEANING you do exist and can go back in time to kill him....and so on!


I remember Stephen Hawking talked about this. The solution to the paradox is basically that backwards-time travel isn't possible, or at least that's what he believes. :tongue:
Reply 44
Original post by Ilyas
what happens when a unstoppable force comes into contact with an immovable object?


Either the object will move, in which case it wasn't immovable, or it won't, in which case the force was not unstoppable.
Original post by 117r
Well, assuming that each step takes the same amount of time, then no.

If you move at constant velocity, then you will, after an infinite number of steps. However, an infinite number of steps in this case won't occupy an infinite amount of time.


But the it is answerable logically therefore I wouldn't class it as a paradox. Of course I've been proven wrong on many occasion before.
Reply 46
Original post by hassi94
I remember Stephen Hawking talked about this. The solution to the paradox is basically that backwards-time travel isn't possible, or at least that's what he believes. :tongue:


What is your fav one? Share.
Reply 47
Original post by Guru Jason
But the it is answerable logically therefore I wouldn't class it as a paradox. Of course I've been proven wrong on many occasion before.


Well that's what I thought, but now I'm not sure. It seems that the word paradox is often used to describe a strange scenario which seems to defy logic, but which can be explained by pointing out something such as a play on words in the original statement.

I guess technically a paradox can't be explained though, so I would probably stick with this not being a paradox.

An example of a true paradox I think would be something like the twin paradox, or the famous example of whether or not a tree makes a sound when it falls if there is nobody there to hear it. Or things like Curry's paradox: If this sentence is true, then Germany borders China.
(edited 11 years ago)
Would you have sex with a fourteen year old girl?

Most answer that they would not.


Now, how about two fourteen year old girls? Does the desire for a threesome outweigh the immorality of having sex with an underage girl?
Original post by ANIGAV
What is your fav one? Share.


Hmm I'm not really sure. The ones that are plain and simple are great; like 'this sentence is a lie' but that's too well known to share here... Maybe the omnipotence paradox? It states basically that if there is an omnipotent being, it could create a rock that was so heavy that it was un-liftable by anyone, even itself. But then it wouldn't be able to lift the rock, and it would no longer be omnipotent. Or it does lift it which implies it couldn't have been omnipotent to begin with.
Reply 50
Original post by TheRealDarthVader
Would you have sex with a fourteen year old girl?

Most answer that they would not.


Now, how about two fourteen year old girls? Does the desire for a threesome outweigh the immorality of having sex with an underage girl?


LOL!
Original post by TheRealDarthVader
Would you have sex with a fourteen year old girl?

Most answer that they would not.


Now, how about two fourteen year old girls? Does the desire for a threesome outweigh the immorality of having sex with an underage girl?


dafuq is wrong with you
Original post by kingkongjaffa
dafuq is wrong with you




Come at me bro!
Reply 53
Original post by kingkongjaffa
dafuq is wrong with you


What isn't wrong with you? <-- Paradox
dunno about the wording, or whether this one has been mentioned before but : can an omnipotent god create an object he can't move?
Reply 55
Original post by Ilyas
what happens when a unstoppable force comes into contact with an immovable object?


what if the immovable object was already moving on its own? if the unstoppable object and the immovable object are travelling at the same speed then they would just continue to travel at the same speed, only instead they would become a unit. However if they were travelling at different speeds, i.e the immovable object was stationary then... the immovable object will remain as it is but the unstoppable force might rebound, it hasnt been stopped, the object has only changed direction

I am no good at this.
Original post by Mystic Creature
Everyone must know about the grandfather paradox. I love that one!

It's like this: Just say you could go back in time and kill your grandfather (also works perfectly well for father too actually). If your grandfather dies, then obv you werent born.....MEANING you couldn't have gone back in time to kill your grandfather, MEANING your grandfather actually isnt dead, MEANING you do exist and can go back in time to kill him....and so on!


A different timeline is created :wink:
A split in the timeline occurs.
You now can't return to your other timeline and are stuck in this new dimension.

Back to the future! Whooo
My favourite is the twins paradox.

According to Einstein, a moving clock runs slower than a stationary one.
t2=t1[1-(v^2/c^2)]^-0.5
Where t2 is the time measured by the 'stationary' observe and t1 is the time measured by the 'moving' one.
{To all physicsists, I know I am being ambiguous on my frame of refernces. Forgive me...I am trying to make it easier to understand.}

Suppose we can travel at 0.975c, where c is the speed of light (3.00X10^8).
Imagine there are two twin girls aged 18. One of them stays on earth and the other gets on a spaceship and whizzes around the galaxy at 0.975c for, according to the travelling twin, 15 years. Let 15 years =t1. When the travelling twin returns, the non-travelling twin will have aged by t2, where t2=t1[1-(0.975)^2]^-0.5. Hence t2=67.5. Which means the travelling twin is 33 but the one that stayed on earth would be a ripe old age of 82.5. Old enough to be her twins' mother. This is the reason why I think that I am going mad by studying A2 physics.:s-smilie:
Depends on the distance to the destination and the length of the first step.

Simple geometric series. :biggrin:
Original post by Guru Jason
Did A level but your explanation is pretty clear. It does makes sense. It's not be a paradox then it seems.


If it helps as well, even though I see you've understood it, I usually like to think of looking at the fraction over 9.
So 1/9 is 0.1111111111111111...
2/9 = 0.22222222222222...
etc
8/9=0.888888888888888...
9/9 as a fraction we know is 1, but continuing the pattern, it's the same as 0.99999999999999999...

Just a way to remember it :smile:
Original post by TheGrinningSkull
A different timeline is created :wink:
A split in the timeline occurs.
You now can't return to your other timeline and are stuck in this new dimension.

Back to the future! Whooo


Yeah ive read about that..it's one of the solutions to the paradox, but still, fun to think about! :biggrin:

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