[HaNzY]

(Original post by 117r)
Well no, not quite, although it has been tested several ways, such as firing odd particles round accelerators and looking at the rates of decay.

As for the paradox itself, it's not so much a paradox as a meaningless question. It only seems like a paradox because the understanding that we have of time is essentially wrong, or at least only applicable to slow speeds. In reality, the concept of time running at different speeds for different people doesn't create a paradox since if you were to actually meet with the person travelling at near the speed of light, there would be some form of acceleration involved, which would disrupt things.

Sorry for confusing explanation, it's probably wrong and certainly very vague. If you are interested in this sort of stuff I'd like to recommend A Very Short Introduction to Relativity. Very clear explanations there.

Thanks for that I am gonna get the e-book version of that book because its pretty cheap, looks very interesting! I am incredibly interested in all this stuff to be honest, but I don't understand it and I don't know hardly any of it. Blows my mind and makes me feel very very lucky to be alive living in this weird and wonderful universe!

[117r]

(Original post by HaNzY)
Thanks for that I am gonna get the e-book version of that book because its pretty cheap, looks very interesting! I am incredibly interested in all this stuff to be honest, but I don't understand it and I don't know hardly any of it. Blows my mind and makes me feel very very lucky to be alive living in this weird and wonderful universe!

Great! I feel the Very Short Introduction series are often very good places to start learning about things, and this one in particular has very good explanations, as reflected in the reviews.

[HaNzY]

(Original post by 117r)
Great! I feel the Very Short Introduction series are often very good places to start learning about things, and this one in particular has very good explanations, as reflected in the reviews.

It actually has a lot of good reviews I haven't heard of this short introduction series before, I've already had a quick look through and have seen quite a few others I fancy reading, Thanks

[Belowski]

Dualism is pretty interesting: the idea that we are separate parts body and mind that interact, though separate. I also like causality: that one action, if the efficient cause of another, can only ever be known with probability and thus is inductive knowledge.

My favourite paradox comes from Descartes' Meditations: that we only know the infinite by being finite and while that is imperfect knowledge, it is also the closest to perfect that the finite mind can get.

[IntelligentIdiot]

(Original post by HaNzY)
Out of curiosity, how close have we been to the speed of light? I mean particle acceleration speeds as I am aware this is probably the fastest we have achieved.

In theory, what you say is possible...hence this implies we can travel forward in 'Earth time' so someone travelling for a good few years could come back and see the future lol and live in the future, however they would never be able to get back in time.

And hang on a sec...you say we can get to 0.9999...recurring the speed of light, earlier someone proved this = 1. Therefore...? I understand that we need infinite energy to get to the speed of light though.

And as another question because I'm so curious and love this sort of thing, if we could get to the speed of light, what would happen? Would we be stationary in time? And if we went faster than the speed of light we would go back in time? I am assuming that faster than the speed of light doesn't exist though? But why??

I always wanted to do physics, my childhood dream was to be an astronaut rather than the conventional vet or teacher lol, but I don't like lightbulb and electric physics lol only space stuff and interesting things like this topic!

I have looked everywhere but unfortunately, I cannot find a exact value of how close we have got to the speed of light.

0.9 recurring is approximately 1 but does not equal 1.

I really want to know the answer to those fundamental questions too.
However I believe since we can't reach the speed of the light, we can only hypothesise what will happen if we could but not be able to prove it. Also, I think that if we need an infinite amount energy to reach the speed of light then we can't reach any speed that is greater than the speed of light. Damn...wish that I have applied for a physics degree and try and get work for CERN rather than apply for mechatronics.

[Joluk]

(Original post by HaNzY)
Out of curiosity, how close have we been to the speed of light? I mean particle acceleration speeds as I am aware this is probably the fastest we have achieved.

I believe protons in the LHC travel at something like 99.9999991% of the speed of light

Theoretically we could make a spaceship which could travel that fast, it would just be a bit of a technical and monetary challenge.

[skibur]

(Original post by IntelligentIdiot)
0.9 recurring is approximately 1 but does not equal 1.

0.9 recurring equals 1 /discussion

[see-are]

"This sentence is false"

false if its true
and true if its false

[jstinson]

(Original post by IntelligentIdiot)
Not yet. To get close to the speed of light we need an almost infinite amount of energy. Interestingly, it is impossible to reach the speed of the light since we need an infinite amount of energy to exert an infinite force but technically it is possible to reach 0.9999(place as many 9s as you want here) times the speed of light.

I disagree 'as many 9s as I want' could mean I want an infinite number of 9s in which case it would be one and therefore incorrect

Anyway my favorite paradox is the Socratic Paradox 'I know that I know nothing at all'

Basically the idea is that as people we seek what is in our own interest, like the selfish people that we are

we act with knowledge to pursue what we think is 'good' for us, however the consequences may in fact be harmful in which case we acted without knowledge. ie ignorance

Assuming we don't intentionally seek to harm ourselves of course...

[Rhadamanthus]

The French Paradox.

It's what allows me to keep guzzling wine and eating cheese.

[Souriretoujours]

aware the majority of these paradoxes are scientific/mathematical but thought I would share an infinitesimal reflection of Oscar Wilde's mastery of the literary paradox.


I can resist everything except temptation.

[DanLorenzo]

Don't go near water until you learn to swim.

Im just kidding.

The arrow paradox. That one gets me thinking. Especially since you do it every moment of your life... Or do you?

[Stiff Little Fingers]

(Original post by TheGrinningSkull)
A different timeline is created
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

or you have sex with your grandma and become your own grand-dad.


I quite like the cat-buttered toast one, because it just makes me wonder - what would happen if I buttered a cat?

[tehforum]

(Original post by Alofleicester)
or you have sex with your grandma and become your own grand-dad.


I quite like the cat-buttered toast one, because it just makes me wonder - what would happen if I buttered a cat?

The cat would freak out and scratch you to pieces.

[A.Bot]

(Original post by IntelligentIdiot)
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.

The paradox lies in the fact that from the frame of reference of the twin who is in the spaceship (let's call her traveller), the girl who stayed on Earth (let's call her caretaker) went on a journey. Hence according to caretaker (and your math), traveller should be the one who aged.

Vice versa, applying the same argument, according to caretaker, traveller is the one who aged more.

Now obviously, it is not possible that caretaker is older than traveller AND that at the same time traveller is older than caretaker.

This paradox is solved by remembering that special relativity only applies in inertial frames. Traveller initially travels away from the Earth, and eventually changes direction and comes back. The change in direction is the result of acceleration, which means that her frame of reference is not an inertial frame. Therefore situations are not symmetrical and caretaker is the twin who aged.

[marky--mark]

I quite like this one:

A man is convicted of treason. The king offers him a choice in his method of execution, and allowed to say one sentance. If that sentance is true, the man will be burned at stake- if the sentance is false then the man will be drowned at sea. What did the man say that resulted in his release?

Spoiler:

Show

I will be drowned at sea.

[mmmpie]

The Abilene paradox: if everybody in a group always tries to do what will make the group happy, eventually nobody is happy.

[Clare~Bear]

(Original post by Bey Taco)
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.

The unstoppable force couldnt rebound cos that means fos a fraction of a second it does stop, to change direction.

[BananaWhale]

What came first, the chicken or the egg?

[mmmpie]

(Original post by BananaWhale)
What came first, the chicken or the egg?

The egg. The thing that laid it wasn't quite a chicken.