/sci/ - Science & Math

>>5362155
If you imagine our spacetime as a 2 dimensional sheet, you should imagine objects with mass as balls. The more the mass, the larger the ball.

Then, when you place the ball on the sheet, it'll cause a giant warp around it, because of it's weight of course. This is basically the best way I know to describe this in an easy to understand manner.

>>5362155
>>5362164

http://www.youtube.com/watch?v=YtdE662eY_M

Visual explanation

There is no absolute time. From your poinf of view, time is passing normally. It's only from others' POV that (your) time is being dilated

>>5362164
Exactly how I think of space time. Imagine the bigger the ball, the bigger the stretch.
If this is still a little hard to grasp, imagine it's on an elastic graph paper, imagining the lines represent time. The lines around the bend where the ball is will stretch.
And I think it does, you age differently depending on where you are in relation to Earth's gravitational pull, I think if you lived our whole life in space you'd life something like 4 seconds longer than someone on earth because it's been stretched... that bit I'm not so fresh on.

>>5362184
I don't understand how to translate that from a flat sheet into 3d space

how do you picture the warping of stretchy graph space?

>>5362198

see

> Around 2:30

>>5362171

>>5362198
Yeah it's a little weird.
I guess if you imagine multiple bits of stretchy graph paper coming from all directions, all intersecting and all getting bent around the ball/planet?
I don't think I can explain it better, since I just sort of got it at the 2D stage. I can understand your frustration though, it's a step up from imagining time as what a clock displays.

But will warping dimensions have such an effect to slow down your natural proces of aging?

Imagine what I'm asking like this: Imagine we all have a fixed time to live, a fixed number of minutes, seconds, and after that our body would simply decompose. Should we warp the time around our body using gravity, would the aging process of our body be influenced? How is this even possible?

>>5362155

All of the interactions between the particles in your body occur at or slower than the speed of light. By warping spacetime, gravity can slow down these interactions causing you to age slower.

time is perception based.
gravity distorts perception
ergo gravity effects time via distortion of perception, pending mass surrounding gravity (or field, that being a black hole)
pretty sure it works like this. but im not a scientist.

>>5362232
living longer relative to what?

you wouldn't perceive yourself as living any longer. but other people would.

You don't need somebody with a degree in astrophysics to explain this to you. A basic understanding in special relativity, frames of reference and time dilation would do. Look up those keywords on youtube or google and you can answer your own question.

>>5362232
So this is from a show I watched not long ago. This is on time more than gravity, but still, adds to the thread.
"Your head might only be 175cm from your feet, but time ticks faster by 687 quadrillionths of a second every hour. By the end of your life your head is 484 billionths of a second older than your feet. If you worked at the top of the empire state building at 373.1m at 8.4hours a day for 260 days a year for 46 years, you'd have worked 14 millionths of a second longer than someone on the ground. Speed also warps time, on the Euro star travelling at 136mph / 220km/hr, by the time you reach paris, you'd have aged 168 trillionths of a second slower than everyone else. If you combined the two, and were in the ISS travelling at 7km/s at a height of 415km, every hour is a millionth shorter than that on Earth. If you spent your whole life up there,you'd be a second younger than everyone else on Earth."

>>5362248
>time is perception based.
HAHAHAHA. LOOK AT THIS FAGGOT. LOOK AT THIS FAGGOT AND LAUGH.
> but im not a scientist.
HAHAHAHA

>>5362270
>>5362232
And of course, height and speed are gravity really. The larger the mass (height from the centre) and the faster it spins, (speed) the higher the gravity.

>>5362184
So is time warped on earth due to net mass, despite us as perceiving it as a normal pace, whereas the net mass we experience in space allows us to experience an equilibrium closer to (for lack of technical definitions) 'absolute' time of the relative lack of mass in vacuum?

>>5362274
b-but it is perception based. without a source of reference how could you observe time? thus perception based. without observation of time,
(prior to or after its observance) then how do you validate its existance? i know thats a bit philosophical but, how else can i explain it?

>>5362305
You can't, you're right. tbh I didn't understand that reaction to your post either.

>>5362296
Well as >>5362248 pointed out (without being a scientist) time is perception based. So what time is on Earth, or what most people call time,is not the same as the rest as the universe. It'll vary everywhere at a guess, but yes I'd guess if you were in the deepest vacuum of space, that'd be absolute time as there would be less gravity to warp it. But space isn't really empty, it's full of all kinds of crazy shit. So I don't know, makes sense though.

>>5362296
>>5362290
thats what i was saying. they just articulated it differently.

>>5362311
Hence my citation. in >>5362306
You said it bro.

>>5362290
hmmm indeed. just like my dick

>>5362319
i'm scientist!

>>5362333
um.... yes actually.

>>5362337
you wanna know a secret... I ain't scientist too.

>>5362337
>infantile cartoon

>>5362364
> calling 4chan's mascot infantile
> on 4chan

It's like you're actually retarded.

>>5362364
I'm scientist!

>>5362364
>passing judgement based on reaction images

>>5362374
>>5362378
>>5362379
> being this anal devastated

>>5362386
>haha I was just pretending to be an angry moron!
>trolled!
why do people think this works still

>>5362155
Anyways, are you still here OP? Happy?

>>5362164
ok, i understand this, but why don't all the balls fall to the center of the sheet?

>>5362386

>>5362198
you can't because it requires 4 spatial dimensions

>>5362290
gravity doesn't depend on anything other than mass

>>5362447
because there's centripetal acceleration. like being on a merry-go-round and it try's to throw you off

>>5362447
Because it's spread out over a large distance and so the balls aren't attracted to each other. Having said that, our solar system is an example where they are actually falling in on each other, that's what our orbit is.

>>5362486
Looked into it after you corrected me. Thanks... that's how I learn. http://www.newton.dep.anl.gov/askasci/phy99/phy99x82.htm

>>5362248
>>5362248
time is reality based
gravity distorts reality
perception follows reality

>>5362305
you assume that the speed of light in a vacuum is constant for all observers

>>5362486
dark matter...

pretty sure gravity is dependant upon it at the macrolevel which might seem unnoticiable at our micro level.

>>5362484
Sure you can; just approximate the space with a bunch of flat polyhedra sewn together. The same trick works in 4D spacetime.

>>5362505
because dark matter is mass?

yes yes it is

still only depends on mass of object

It's a consequence of the fact that the speed of light is constant combined with the fact that it's impossible to locally distinguish between acceleration and a gravitational field. The equality of the inertial and gravitational mass is the cute "coincidence" off which the pretty geometry of Einstein is developed.

>>5362502
but a constant flow of time implies origin and observance. nothing we have observed, short of God(which remains directly unobserved[able])
has be continuously constant without origin. ergo no, time isnt reality, mearly warped perceptions of such at different angles.

how's /fit/ been, i heard its pretty gay over there.

>>5362490
ok, but given that matter has gravity, why doesn't everything collapse in on itself?

in terms of the analogy, it shouldn't matter how far away things are, because they will all roll to the 'center'.

would dark matter explain this? or does this require conceptualizing the universe as polymerlike in that it contains both crystalline and amorphous regions, where everything begins crystalline but relaxes to amorphous over time, accounting for universal expansion.

>>5362524
i'd say dark matter is special mass like photons but it directly effects galaxies. its a funny macrocopic thing, i think harnessing it would either A: cause galatic instability which would disrupt galaxys holding together(super massive black holes would no longer sustain themselves) or B: palpatine.jpeg UNLIMITED POWAH!!!!!!!!!!!

>>5362533
>>5362447
>>5362490
Because of some combination of everything having momentum sending it in various directions from the big bang and space itself expanding faster than gravity could pull things back together.

>>5362568
Could the polymer model be a viable explanation for space-time expansion?

It 'sags' (relaxes in polymer science) as a result of the constant loads in the form of balls, which results in expansion/ chain relaxation.

What do you think?

>>5362533
>>5362568
This. It's a case of things are moving... live with it. You have to expand your mind rather than literally seeing balls on a sheet.

>>5362579
I'm trying to extend the analogy, thanks for your insightful comment.

>>5362524
mass and pressure

>>5362576
So what testable predictions does that model generate? I can't think of any, but if it helps you visualise what is going on, then it's as good as any other such construct.

>>5362576
>>5362598
Actually, scratch that, the model does not work. If the expansion was a consequence of gravity acting on spacetime, one would expect the expansion of space between two objects to be independent of their distance; observations indicate that is linearly proportional to it.

>>5362598
I wouldn't know, I study polymer science. I'm writing an article and was trying to use this analogy, but it fell apart for me at
>>5362533
So, in this theory, dark matter is an effect of crystalline space-time. Gravity is an effect of matter which results in stress relaxation (expansion of the universe)

this kind of makes sense to me when you consider that the universe is expanding at an accelerating rate - the crystalline regions decrease as total mass increases as the result of that polymeric relaxation.

>>5362624
where is the stress coming from?

>>5362642
matter

>>5362617
that's good thinking. would you say that spacetime has a fundamentally quantum nature? just curious for your opinion.

>>5362644
I could try saying something about it if you could define a "fundamentally quantum nature" for me first...

>>5362667
I will try again.

Does spacetime operate on a continuum , a background to the matter of the universe, or is spacetime quantum in nature, in that it is made up of fundamental building blocks and fibers - similar to a 2d polymer made up of individual chains

Go read a fucking book on GR instead of asking a bunch of imbecilic highschoolers on break what they think.

>>5362548
No, mass is just mass. Photons are mass-less gauge bosons that mediate the electromagnetic interaction. Dark matter is just mass that doesn't interact electromagnetically.

Does anyone take this guy seriously? I almost feel it's a crime that he might mislead someone into believing him.

>>5362155
I'm not going to try and explain this because I need to review relativity before I feel comfortable that what else I could say is correct, but you need to treat space and time the same way. It also arises, like someone said earlier, from giving light (photons) a constant, finite speed in all reference frames.

>>5362672
Space and energy are not inherently quantized. Quantization arises when you set boundaries on your system. IE: The spectrum of light is continuous, a free electron (one moving in an imaginary infinite space that has nothing else in it, no other fields or matter) can have any momentum/velocity and be at any position.

>>5362685
I take it you don't put much faith in loop quantum gravity then?

Gravity IS a distortion of time. Space and time are changed by the presence of mass, so that when you're near a massive object, your future points ever so slightly towards the centre of mass. If you do nothing, simply existing and moving into your own personal future will lead you to collide with the planet.

One of the side effects of this distortion is that time gets slowed down near massive objects.

>>5362672
Ah, in that sense. Well, I'm aware of certain theories that were fashionable a while back (loop quantum gravity, in particular, might be something that you would want to look at), but I really can't even begin to guess whether they would have more or less merit than continuous theories. Sorry to not be able to give a satisfactory answer (although I'm under the impression, and backtracked on typing out a somewhat lengthy off-topic excursion as to why I think that, that in general, asking people about their hunch on unresolved questions in physics is much less sensible or useful than it is in mathematics).

>>5362725
I'm sorry, and I agree that it's not directly useful but still fun to think about. Like I said, I'm studying Polymer Sciences. I recently had an opportunity to interview Dr. Ashtekar (chief scientist behind lqg) and my mind has been buzzing with this stuff ever since. In his words, he described space-time as polymer-like, and that was before I told him what I studied. It blew my fucking mind.

>>5362680
>/sci/ - Science and Math
> Don't discuss science!

>>5362743
It certainly would be fun to think about - it's just that I feel disproportionately unqualified to even attempt to. If you are aware of any expositions of LQG that do not require a plethora of prerequisite physical knowledge (in general, having a background in an unholy combination of discrete maths and categorical logic, even plain old quantum electrodynamics is already too thick in idiosyncratic notation and conventions for me to follow the way it is taught at universities), I would be very curious to see them; it would help if I could just get an idea how the theory bypasses various granularity blowup effects that would make any naive attempt to discretise spacetime very easy to disprove experimentally.