The Butterfly Effect

[zanzibar]

I've heard that time can be relative and can be described as a river that flows through our universe. That time isn't entirely constant everywhere.

As your relative speed increases, you start to experience time at a slower rate.  Other people observing you see time in your system moving at a slower rate.  If you had a twin, and you left the earth moving really really fast, and then you came back to earth really really fast, you would be younger than your twin when you got back and compared notes.

The proof of this is tests done at high altitudes using atomic clocks.

When i see a black hole, in my mind, i think of destruction, but now we see them at the center of every galaxy.

So?  A black hole is essentially a super massive star that is so massive that not even light can escape its gravitational field.

What stops a black hole from taking in mass, because i've heard of dormant black holes that no longer take in large amounts of mass.

I haven't heard the term "dormant black hole".  I would guess that it refers to a black hole that isn't near anything, so it isn't taking in anything currently.

Where do you think a black hole would take you? Basically, you have this huge blob that is sucking in mass because of it's gravity and it's becoming denser and denser. Could it actually take you somewhere or would you be smushes like a glob on top of all the other matter that's in it.

A black hole isn't understood today to be a blob.  It's an incredibly large amount of matter occupying an extremely small volume of space.  The diameter of a black hole - not the event horizon, but the black hole itself - may be as small as the plank length.  Basically, it's the size of a particle.

Yes.  It's that tightly compressed.

What evidence is out there that black holes even exhist?

Photographs, galaxies, gravitational lensing, radiowaves from space, math.


Edit:  Check out http://www.eso.org/outreach/press-rel/pr-2002/pr-17-02.html , including the video clip reconstructing the observed movement of stars near a black hole.

[Datruth]

"What evidence is out there that black holes even exhist?"

Photographs, galaxies, gravitational lensing, radiowaves from space, math.
~~~~~~~~~~~~~

Can you explain that to me?

Photographs?

You basically just named a bunch of things but you didn't explain how they actually proved black holes.

[zanzibar]

Photographs over time show the movement of certain stars is influenced by super-massive invisble objects.

Gravitational lensing is when light bends around black holes on its way to us.  The Einstein Cross is a superb example of this.  You can find images of it on google images.

The forces involved in pulling a galaxy together demonstrate the existence of super massive bodies.  Black holes are really the only likely explanation for so much force to be coming from such a small area.

Radiowave imagery lets us "see" black holes.  As black holes swallow matter, they release large amounts of radiowaves that we can observe.

Black holes were predicted using math well in advance of being discovered.



I can make more posts, but really... you should just google it.  There's a lot of information out there.

[Vengeance]

Getting back to the original topic of this thread, this idea that a butterfly can "cause" a hurricane to occur later is really a gross oversimplification of pop science.  I studied Chaos Theory and worked in a research lab using it for several years back in college, so I do know something about it.

One of the central findings of chaos theory or of studying chaotic systems is that they are impossible to predict accurately over time.  A tiny change in initial conditions can result in a large difference in future state out in time as you watch the system evolve.  If you run simulations of chaotic systems, you can see this at work.  You set up some variables with random values, and simulate 1000 iterations of your system and record the final values.  Then you change 1 of those variables by 0.000000001 and re-run the same simulation, and you will end up with totally different resulting values.  This means that if you are looking at a real system and measuring its initital state, you cannot predict (accurately) its state after 1000 iterations, because even if you are off by a tiny bit, your prediction has no value.

You would think that the smaller amount you change the initial settings, the smaller the difference in final results is, but it isn't always true.  How true that is, and how far out you can stay within a certain error factor, depends on how chaotic the system is.

This doesn't mean a change in initial conditions will make a system do something it cannot do though. Moving a water molecule 1mm might result in a differently shaped snowflake than you would have gotten, but it is still going to be six-sided and "look" like a snowflake.  We don't get hurricanes over land.  Tidal waves don't start on mountaintops.

In the same way, the butterfly isn't "causing" a hurricane.  Instead the author is saying that in trying to predict the weather, if we take into account millions of variables and measure pressure and windspeed every 1cm across the earth to 10 digits of accuracy, and we fail to take into account a single butterfly, eventually our predictions will be off and we will fail to predict that a hurricane is occurring over a certain spot a year from now--or 10 years from now.  Timeframe of prediction is crucial.  If you only want to predict the weather 5 minutes from now, sticking your head out of the window is enough data points to be right 99.99% of the time.  Predicting it 5 years from now will be impossible forever.

We can't predict the shape of a snowflake, or the exact flicker pattern of flames in a bonfire, or the ever-changing shape of clouds in the sky--and yet these always "look" almost the same to us.  Almost is the key word here.  And since they are "almost" the same, we can "almost" predict how they will act but not quite.

And that is why most people find these things endlessly fascinating to watch, sightsee and take pictures of--capturing 1 individual in a trillion trillion trillion possibilities.

- Vengeance

[Datruth]

If you only want to predict the weather 5 minutes from now, sticking your head out of the window is enough data points to be right 99.99% of the time.  Predicting it 5 years from now will be impossible forever.

- Vengeance

That isn't true and shouldn't be used as a fact.

We know that all things we see today are an ordered system, there are laws that can't be broken and each atom has it's own qualities.

I predict, once we delve into this ordered system some more and understand it better, we will have the ability to predict weather.

This is far off from now, i mean the sun might destroy the earth before we ever figure this out, but i still feel that we are in an ordered system and that with more knowledge we can understand this system better.

That and the effectiveness of our measurements will one day help us predict this seamingly chaotic system.

[zanzibar]

I predict that the sun will rise tommorow. 

[Datruth]

I predict that the sun will rise tommorow. 

$5 on Paypal, YOUR ON!

lol

[Wired_Crawler]

Can You give me a link to a movie showing this, filmed through some kind of microscope?

I doubt you could observe such behaviours using conventional microscopes.

Errm... It was the rhetorical question, Zanzibar. I know that it can't be observed directly. What I want to say is, that you don't know, if photons are stopping at other particles, you only have a theory, which converge with observations of results of passing light thrug a medium and which is well supported by math. What really happens in nano-world (pico- ? femto- ?) - we don't know.

Other particles that move at the speed of light include the gluon and theoretically the graviton

Neither free gluons nor gravitons were observed. They are just theory (nice one) describing interactions between other particles. Until somone will find a trace left by gluon (graviton) you can not say "gluons and gravitons are particles which can travel at lightspeed".

Heh, and what would happen, if photon stopped in pure vacuum ? Would it just... vanished ? If it has no rest mass (no rest energy), it simply does not exist... Right ?

Your comment has the same value as the sentence "Purple monkey dishwasher".  Photons exist and have energy.  They do not stop in a pure vacuum.

Again - It was not a question, it was a sentence showing, that your statements are of the same value You mention above "Photons exist and have energy", because they are moving, at least according to current theories which assume that they have no rest mass.

Tachyons may exist if their starting conditions allowed them to have such properties.  If something started off existence moving faster than the speed of light, then it would still be moving faster than the speed of light today - and theoretically backwards through time as well.

Currently tachions are result of playing with imaginary numbers. IF the theory is right (if they do exist), there is no way we can detect any (they are far away and long time ago ). Technically - they don't exists (until we produce and observe one).

You set up some variables with random values, and simulate 1000 iterations of your system and record the final values.  Then you change 1 of those variables by 0.000000001 and re-run the same simulation, and you will end up with totally different resulting values.

And if You repeat the same simulation with the same starting conditions, You get what ? The same result or diffrerent result?  If the result remains the same - your system is not unpredictable, it follows well defined rules (even if You don't know those rules).

This means that if you are looking at a real system and measuring its initital state, you cannot predict (accurately) its state after 1000 iterations, because even if you are off by a tiny bit, your prediction has no value.

It only means, that you don't know all required variables, you do not take into account all of single objects involved in your model and you don't know the real formula allowing to calculate everything (see ->Unification theory, ->Theory of everything etc...)

I predict that the sun will rise tommorow. 

You are right in the world of cosmology.
In the world of quantum physics You may be wrong  .
In the world of theory You may be wrong.
If the dense cloud covers the sky, so dense, that no device can detect sun through it (your eyes, if you haven't anything else at the moment), You will never know if it raised or not. It could also simultaneously rise and not rise.  Read about ->Schrödinger's cat (although You probably know about that "experiment", Zanzibar).

And about movie - I haven't seen it yet, and I think I'll wait untl it is broadcasted in TV. There are so many movies covering this topic - have you watched "Back to the Future" ( ), or "Time Cop" ? There are more similar productions, I don't remember them atm. I also remember a story I read long time ago, I cant recall the author nor the title. In that story people were traveling back in time to hunt dinosaurs, for fun. Of course, they were doing it in a way which "guaranteed" leaving the future (I mean present) in unchanged state. They used special artificial paths, they always were taking all bullets back to the future etc. One day one of hunters panicked and he left he path. He had only some mud on his shoes, so they though it will be OK. But they did not notice a butterfly sticked to the mud. I think You already guess, that they found quite different world after returning... Just another example of "butterfly effect"

[zanzibar]

Wired_Crawler,  I find your statement that "things don't exists until we produce and observe them" to be ludacris.  And I know plenty about quantum physics and the uncertainty principle and its various applications, there's no reason to insult me just to make a point.  Your own statement isn't even backed up by quantum mechanics:  Things exist, even if we aren't directly observing them.  They just exist in a different state.


Even on a cloudy day, the sun still rises.


Edit:  I'm pretty sure gluons have been observed in experiments using particle accelerators, so there you go.

Edit times two:  Chaotic systems are still governed by laws.  The point is that the variables are extremely sensitive.

[Xordan]

Things exist, even if we aren't directly observing them.  They just exist in a different state.

Or in multiple states simultaneously.

Also yes, gluons have been observed. We're pretty sure they exist, and are part of our standard model.

[zanzibar]

Or in multiple states simultaneously.

I'm pretty sure that counts as a different state.

[Wired_Crawler]

Wired_Crawler,  I find your statement that (...)

*sigh*

OK, OK. I give up. My oratorical skills (especially in non-native language) are not high enough to continue this interesting discussion. Sorry if I wrote something offensive.
And yes, my knowledge may be covered by thin layer of dust, so I find all informations above valuable.
 

[zanzibar]

Wired_Crawler,  I find your statement that (...)

*sigh*

OK, OK. I give up. My oratorical skills (especially in non-native language) are not high enough to continue this interesting discussion. Sorry if I wrote something offensive.
And yes, my knowledge may be covered by thin layer of dust, so I find all informations above valuable.
 

We aren't talking about things which are that new.  And it's not your communication skills that are lacking.

[Mindari]

yea no room for non genious's in this discussion

[miLosh]

i just stumbled over this thread and think i should clarify some points from a astronomical point of view (i wont quote everything cause i'd had to quote almost all posts in this thread

generally speaking: we do not know anything for sure, nothing is to be taken for granted. take the blackhole theory, it is a beautiful theory and would simplify our view of the universe by many means. unfortunately, recent observations show that the theory might not be much more than a theory - that is wrong. zanzibars definition of the classical black hole was quite right, it's a singularity created by an imploded star (which must have had about 3 sun masses IIRC). btw, a dormant BH is exactly what zanzibar wrote, a blackhole that has consumed all mass that is within its schwarzschild radius (that is, the area of effect to put it simple).

so why should the theory be wrong? because its states that BHs do not have a magnitc field and that does not go along with receint observations of a particular quasar. they show, that that "black hole" has indeed a magnetic field - and because of that, it cant be a BH but must be a "MECO", which stands for "Magnetospheric Eternally Collapsing Objects". further trouble comes with that, as MECOs and BHs are mutual exclusive - either we have BHs or MECOs in the universe, the existence of both is not possible. see here for more information:
http://www.newscientistspace.com/article.ns?id=dn9620&feedId=online-news_rss20

that does not mean that we have to overthrow all BH theory and question einstein in general, for the MECO theory is also, only a theory. but it should remind us that nothing is to be taken for certain in our universe.

so lets continue to the speed of light topic. as stated by the theory, nothing with mass can exceed that speed. but that does not mean that C is the fasted speed in the universe. a practical experiment with lasers and xeon gas (IIRC) showed speeds around 300 times C. and there are the quantum physics who observ twin-particles that clearly interact with each other in no-time - literally. if you change a property of one particle, it is immediatly changed on the other without any delay. this passing of information from one particle to the other is considered to be faster-than-light. that does not prove that we could theoretically travel faster than light, because we consist of mass and information does not, but it states that C is not the highest velocity we experience.

and well, there is also a philosophical view to it: what is the speed of a thought? ^^

alright, back to the original topic of this thread: time travel. oh i love timetravel theories, they are so full of paradoxons that it can busy my brain for days when thinking about it. a simple one: if im going back in time and kill my mother before she gave birth to me, what will happen? will i simply vanish? if so, how could i go back in time then? and so on and on... so to me, timetravel is strictly a science-fiction term that lets us dream of "if i only could...". but in a universe that is based on cause and effect (at least in the macro-universe, im aware of the quantum effects where the effect precides the cause) it simply makes no sense. the jar falls first from the table, then it breaks. but timetravell says that a jarr can break before it falls from the table.

"but if we could travel faster than light we could go back in time..," i hear some of you exclaiming. yes, theoretically. period. it is nice to think in theories because no one can prove it wrong (thats why the string-theory is considered the most perfect theory ever made: no one will ever be able to prove it wrong). but we should not forget to apply real-world-experiences to our theories and far more important, that we are only at the very beginning of understanding our existence. nothing is for granted.