/sci/ - Science & Math

[Anonymous No.5363015]

Alright, just some curiosities of an undraged kid who's never been on /sci/.

Time dilation, and how does it even. The way I see it, time dilation is simply because you're moving "Through the light waves" Meaning that if you were to be moving away from an object at the speed of light (To stop any arguments about that, let's say very close TO light speed) Would that object appear "Frozen in time", While whatever you were heading directly at would be moving faster through time? And if this is the case, then why is time dilation in affect for things such as the ISS?
And also, how does gravity cause time dilation?
(Another completely unrelated things,what makes a tesseract "Four-dimensional")
I might be bumping this with a few other things I didn't completely understand, but this is just one big mindfuck to me.
Picture mostly unrelated.

[Anonymous No.5363019]

inb4 ban

[Anonymous No.5363021]

Also, obvious typos are obvious, and also something that is probably going to be easily disproved but just some random thought I had. If the world is supposedly going to end with the star expanding, what if (Because everything is getting more distant) we survive because of the fact that, by that time, we've gotten far enough from the sun? Meaning that, we're moving away in sync with the heating of the sun? (And again, i'm not sure if it's the solar systems as a whole moving apart, galaxies, etc, I know less about this than I do in the OP.)

[Aqueous No.5363025]

>>5363021
My crackpot idea is that time and expansion are interconnected. make of this what you will. also, enjoy your eventual ban

[Anonymous No.5363027]

>>5363025
Eh, I could care less about the ban honestly, but if you could can you expand a little more on your idea?

[Anonymous No.5363038]

>Time dilation, and how does it even. The way I see it, time dilation is simply because you're moving "Through the light waves" Meaning that if you were to be moving away from an object at the speed of light (To stop any arguments about that, let's say very close TO light speed) Would that object appear "Frozen in time", While whatever you were heading directly at would be moving faster through time?
You know, it's a nice intuition you have there.
However, no, this is not what causes time dilatation, because light waves in a vacuum always move at light speed, even relative to you in this thought experiment.
What you are thinking about, however, is not completely dissimilar to the optic Doppler effect: object moving away from you quickly will appear "reder" than they really are.

[Anonymous No.5363049]

>>5363038
Then what actually causes it?
I recall reading somewhere about, because of the gravity effects of time dilation, a twin living on top of a mountain would age slower than one living at the bottom of the mountain, but if they went to meet up, they would appear to have aged the same, While I'm not sure if this is only for time dilation caused by gravity, or if this also applies for time dilation caused by velocity. I do, however, remember reading about a twin taking a round trip on an airplane, I don't remember it too well though.

[Anonymous No.5363054]

>>5363049
>Then what actually causes it?

Nothing "causes" it, it's just the way time and space work. In your timeline, things that are moving through space relative to you travel more slowly through time.

[Anonymous No.5363059]

oh man this guy is gonna be banned from all boards pretty soon

[Anonymous No.5363065]

Alright then, just another thing that probably has no relation at all to time dilation.
If you're looking at a star that's, lets for simplicity say 1 light year away. Because the light takes 1 year to reach us, we're seeing the star as it was a year ago. But what would happen if you were to almost instantly travel to that star?

[Anonymous No.5363073]

>time dilation
http://www.iakoad.com/blog.php?id=28
Despite site name, guy knows his shit. It's explained using algebra so people without a shit-ton of maths can grasp it.

(a tesseract is often considered to have four spacial dimensions, basically like the three we see and perceive, and then an extra one. It's basically a mathematical idea. You can also consider its fourth dimension to be time, but that changes things).

[Anonymous No.5363090]

>>5363065
>travel instantly
At this point, you're travelling faster than light. And things get strange. You would, more or less, be travelling backward in time. This guy:
http://www.projectrho.com/public_html/rocket/fasterlight.php
Sort of explains it, and the idea mainly has to do with reference frames (and there being no preferred frame) and lorentz transformations. Basically, if you can travel instantly, than you can move backward in time relative to a non-travelling observer.

As the old saying goes: Faster-than-light travel, Relativity, Causality; pick any two.

[Aqueous No.5363100]

>>5363025
I wish I could, but I'm still trying to figure it out myself. here's what I've got so far:
time, as i see it, is a constant interaction between two extremes of a spectrum.
those extremes are "nothing" in which no possibilities exist, and "everything," in which all possibilities exist (though perhaps not all at one, just in the sense that all possible combinations of materials have come to exist).
that would make the big bang "nothing" and the eventual fate of the universe "everything."
so I'll just call "nothing" past and "everything" future.
that would mean that any given moment or "present" is an interaction between past and future. for example if you run an experiment in physics, the results are the same regardless of which direction time is running in.
this leads me to believe that the future as much influence on the present as the past.
my crackpot idea is that the expansion of the universe is what is moving us from the "nothing" of the past to the "everything" of the future, which we perceive as time.
now, time dilation comes into the picture like this: I believe that gravity is simply resistance to expansion. The more massive an object, the more gravity, the more resistant it is to the expansion of the universe (space time), and therefore it is affected less by what we would call time.
yes, yes, I know I'm crazy and this is a crackpot idea.
this all fits in with my other crackpot ideas of what Dark Matter/Dark Energy are

[Anonymous No.5363121]

Something else that has nothing to do with anything in this thread.
Lets say existance as a whole, the way I see it, will never end. There will always be something and things will always be happening or eventually happening. The way I see it, existance of matter, dark matter, anything at all will exist infinitely (Hard to explain) So in an infinite frame, shouldn't everything happen an infinite amount of times, except a few things that would cause paradoxes, such as existance ending?

I'm seeing it like this, say in one year, there's a 50% chance of a star to be created. In 10 years, that means about 5 stars will be created. In 100, about 50 will be created, and so on. Meaning that in an infinite time frame, and infinite amount will be created. Now let's say there's a 0.0000001% chance of a website being called 4chan existing on a planet with life, in an infinite time frame this will happen an infinite amount of times.
Now lets say there's an extremely low chance, too low for me to type out, that there will be a website called 4chan, on a planet exactly like ours, with these exact same responses typed out the exact way. But in an infinite time frame, it'll happen an infinite amount of times, meaning that this has all happened before, and will happen again.

[Aqueous No.5363135]

>>5363100
I forgot also to mention that I believe the constantly changing interaction between past and future is linked to the uncertainty principle

[Anonymous No.5363147]

>>5363121
First of all, existence will end. It will take a long time, but eventually star fuel runs out, eventually black holes die, and even eventually protons decay. It takes a long, long time, but it does happen.

If things did exist infinitely, then yes, everything would happen within the laws of the universe. But, since the universe does not have infinite time, this won't happen.

Your numbers are horribly off, but I get your gist. If we're talking infinities, than yes, it will happen. But we're not, and that's the important part. We know, for example, that time probably had a beginning (if you trace everything back to the Big Bang, you find that time ceases before it), and we know it probably has an end. There's a long stretch in between, but nothing is truly infinite.

Also, infinities are tricky. See pic related.

[Anonymous No.5363151]

>>5363021
>obvious typos are obvious

[Aqueous No.5363156]

>>5363147

what is existence? without sentience I wouldn't really say existence...well....exists.
that being said, the universe will eventually be "dead" for all intensive purposes as expansion will have spread everything too far apart for any interaction.
However, since I believe black holes and universes are the same thing, our universe will have birthed countless others by this time and so on.
therefore existence will never end on a larger scale, and it probably never began. we are just limited in thinking this way because our sentience "began" when we were born and "ends" the day we die, but matter and energy are not born or destroyed, why would existence behave in a way that the fibers of our universe do not?

[Anonymous No.5363163]

>>5363147
But then again, it all started from nothing. So even if time does end, and there's just a huge vacuum with nothing in it, couldn't it start again?

[Anonymous No.5363179]

>>5363163

Not the same. The universe started from a crazy amount of energy/matter (same thing, really) being concentrated at a single point, which exploded. It will likely end with all that matter spread throughout space in a more or less uniform distribution.

http://en.wikipedia.org/wiki/Future_of_an_expanding_universe

[Anonymous No.5363199]

>>5363156
>what is existence? without sentience I wouldn't really say existence...well....exists.


it won't exist for you, but it'll exist for the observer.

[Anonymous No.5363203]

>4-dimensional movement

Okay, imagine a 2-dimensional guy in 2-d space, in other words on a flat plane. He starts at an origin point and goes off in one direction. If he doesn't change direction, he will go on forever and never get closer to the place he started from, right?

Now imagine that same guy traveling on the surface of a sphere. He still thinks he's on a regular 2-d plane, but no matter which direction he picks, he'll form a great circle around the sphere and end up where he started again, right? If he starts at the intersection of the Prime Meridien and the Equator and goes due west, he'll travel all the way around the world and end up back where he started. Like in Final Fantasy games, the way the map wraps around.

A 4-d sphere or 4-sphere would work the exact same way, except you could also go up or down relative to the surface you perceive and still get back to where you came from. It may help to think of yourself flying through space rather than being on the surface of a planet to understand it. You go in any direction, but loop around.

[Anonymous No.5363208]

>>5363100
>>5363121
>>5363147
>>5363156
What happened ITT?
Who let that guy in?

[Anonymous No.5363212]

>>5363015
I also have a question about time dilation - if you travel a distance of, say, four light-years at the speed of light, for whom does the four years elapse? For you, or for the relatively stationary observer? If the latter, how much time do you perceive elapsing in that time?