/sci/ - Science & Math

but what makes the gravity that pulls the balls downward into the pits?

>>10121141
That's not the purpose of this demonstration. This is demonstrating the effect of gravity, and is a sound visualisation.

Yes and now imagine this in 3-dimensional space as the demonstration only visualizes a 2-dimensional plane.

I was laughed out of another thread for explaining the same way. Would it be fair to say that space time doesn't exist unless and until there is matter there to warp space time?

>>10121189
No

>>10121189
>>10121666
actually it is very valid to say this

>>10121137
I once visualized gravity with a cannonball and feather falling from a slanted tower. They both hit the ground at the same time, it was glorious indeed.

>>10121137
If you're not an NPC and have at least modicum of imagination it's pretty easy to imagine this blue thing as a 3D Space Blue Matter and how it's tighten at those points from all directions. Or at least imagine that on the other side is the same blue matter and it's also sagging like that to those balls, and then imagine it happening from all possible sides.

>>10121137
Pic related.

>>10121141
Exactly. Spacetime is bullshit.

>>10121149
Also this. Which makes it even more retarded.

spathe tiem

>>10121137
This just supports the flat earth theory

>>10121908
> parking as the great one

God off my board

>>10121141
The theory is that massive bodies distort space in the direction of the time dimension. Presumably the flow of time from this dimension (or whatever) causes things to be sucked inwards, although there is no evidence of anything of the kind and it is complete hand wavy bullshit. Great for Star Trek and comic books tho.

>>10122423
There are like five or six tests of general relativity that have all been confirmed.

>>10122438
Shut the fuck up. No there aren't. Most claims that "relativity has been demonstrated" either soundly refute it and are bizarrely claimed as successes or are hypothesized outcomes of earlier theories.

>>10121137
I wonder if it's easy to simulate a free return trajectory with that model, that would be cool

>>10121149
>2-dimensional plane.

I have this hypothesis which I'm pretty sure this is based off a theory that's based off another theory that may be inaccurate, so take this for what it's worth...
What if the surface of a black hole is 2D space. Imagine and entire 2D universe that's actually the surface surface of a black hole. You might have pockets of matter in this surface layer that create dimples. These dimples exist in 3d space, but are invisible within the 2D universe/layer created on the surface of the black hole. In such a case, OPs pic is a perfect graphical representation of gravity in a 2D universe.
With that said, it's easy to imagine gravity in a 3D universe, that's actually part of a 4D black hole. The dimples created in our universe extend out into the 4th dimension along the W-axis so we can't perceive them, even tho they have an effect on our space.

>>10122423
>Rigorous mathematics
>handwavy bullshit
You're the only one bullshitting because you can't understand tensor calculus

>>10121137
The man giving the presentation was my ap physics teacher back in high school. His is still my favorite class I've ever taken.

>>10122572
So the dimples created in our 3D universe extend out into the 4th dimension, and do these extend into the 5th dimension, and the 6th dimension, and so on?

>>10122441
b8

>>10122313
The great one wouldn’t have used a feather

that relies on gravity though

>>10122614
A curved space doesn't have to be embedded in a higher dimensional space. And no, space doesn't just curve into the 4th dimension. Spacetime itself intrinsically is curved

>>10121857
>Very valid
So, you're saying a space doesn't exist unless it has curvature and torsion?
>>> /g/ tfo

>>10122634
So dimensions are physically separate from each other, or only some are?

>>10122646
What do you mean by physically separate?

>>10121137
Are there actually any demonstrable experiments that show Mass attracting mass? Something that can be seen in practice not just text?

>>10122668
Can you make any "dimples" in our 3D universe without it affecting the 4th dimension?

>>10122706
No, you have to transform time too, otherwise the speed of light wouldn't be constant

>>10122741
Why isn't space in the 4th dimension?

>>10122423
Definitely been proven man. If you shoot photons at Venus and wait for them to come back (sonar-ish) the time that we would expect based on the distance is not what is observed. What does give the correct value is calculating time dialation caused by the suns mass (gravity) GR is real as fuck man. SR is kinda hokey to me though.

>>10122755
Space and time transform into each other. The time axis of a moving object is (hyperbolically) rotated towards the space direction and vice versa.

>>10122679
Cavendish did that centuries ago.

>>10122798
What makes space different from time?

>>10122813
They have opposite signs in the metric tensor, at least in SR.

>>10122804
Cavendish also experimented with electrostatic attraction. Just as well lead balls like the ones he used in the Cavendish experiment aren't highly electrically static! Since that would invalidate the experiment.

>>10122823
Therefore two sides of the same thing?

>>10122825
The good thing is that we don't have to rely on ancient experiments.
https://phys.org/news/2018-08-ways-gravitational-constant.html
But you're probably a crank so I don't know why I'm even posting this.

>>10122825
You can always reproduce it yourself and "invalidate" it.

>>10122829
I wouldn't say so, you have to consider the arrow of time as well.

>someone makes an analogy of time or space with food or plastic

>>10122837
>>10122838
>https://phys.org/news/2018-08-ways-gravitational-constant.html
But Newtonian gravity has already been disproven? It's not a force between the centers of mass. The experiment still uses a torsion balance (strings are never perfectly straight, and will twist), which is retarded as well.

That's the best you've got?

>>10122846
Time has a direction?

>>10122860
Newtonian gravity is a special case of GR, do you even physics? Maybe turn your brain on once in a while.
But nothing I say will convince you. Stay schizo my friend.

>>10122866
What's attracting the balls together, curved space time, or a force between the centers of the two masses?

>>10122860
>But Newtonian gravity has already been disproven?
No it hasn't, we just found its limitations.

>It's not a force between the centers of mass. The experiment still uses a torsion balance (strings are never perfectly straight, and will twist), which is retarded as well.
What are you talking about?

>>10122872
Curved spacetime. And the strength of the attraction is consistent with GR and Newtonian gravity and can be independently reproduced by different people and with different experimental setups. Also the experimenters already accounted for errors. It's the +/- after the value that you thought was just for shit and giggles.

>>10122879
Wait, you don't remember the day when Newtonian gravity was disproven and everybody floated into space?

>>10122888
You are not making sense.

>>10122891
I just lead the crank's argument ad absurdum

>>10122879
>No it hasn't, we just found its limitations.
What? Is gravity a force or not?
>What are you talking about?
The experiment is inherently retarded with too many variables involved. Using strings is just dumb and really unscientific, something a 5 year old would use.

What about the moon's gravity? What about the sun's? What about the earth's magnetic field? The static electricity present in the balls and apparatus?

gravity force is an illusion. when you jump off a building there is no force pulling you down. the ground is literally accelerating upwards towards you due to the curvature of spacetime. this also explains why differently massed objects accelerate at the same speed

>>10122896
>What about the moon's gravity? What about the sun's? What about the earth's magnetic field? The static electricity present in the balls and apparatus?
So that means doing the experiment at different times with different sun/moon constellations and with different strings and balls would lead to radically differentl outcomes. It doesn't. Explain why it's always consistent with the theory. THAT is scientific, not your hogwash.

>>10122881
>And the strength of the attraction is consistent with GR and Newtonian gravity and can be independently reproduced by different people and with different experimental setups.
But there still isn't a "gravitational" constant, it keeps changing.

>>10122896
>What? Is gravity a force or not?
You can think of it that way when you are dealing with simple cases, but ultimately you can't, just like you can't think of electromagnetism as a force.

>The experiment is inherently retarded with too many variables involved.
Nice baseless opinion you have there.

Using strings is just dumb and really unscientific, something a 5 year old would use.
Ibidem.

>What about the moon's gravity? What about the sun's? What about the earth's magnetic field? The static electricity present in the balls and apparatus?
The gravity of other bodies is not that relevant compared to the one between the two balls. Lead does not react to magnetic fields, and do you even have proof of Cavendish not taking into account electrostatic charges? He was a brilliant man with experience in that particular thing, as you said, how come the charge of the balls was always the same that would lead to gravitational-like forces during all his experimental runs?

>>10122423
>GR is hand wavy bullshit
>literally required for some tech to work

>>10122908
>So that means doing the experiment at different times with different sun/moon constellations and with different strings and balls would lead to radically differentl outcomes. It doesn't.
Who is getting funding for these experiments? Have they been independently verified?

>>10122938
>I-It's a conspiracy
Ah, the last resort of the schizo. I guess I won.

>>10122920
>You can think of it that way when you are dealing with simple cases, but ultimately you can't, just like you can't think of electromagnetism as a force.
It's funny how electromagnetism attracts matter together, yet you are certain that gravity isn't a form of electromagnetism, and is instead some bizarre thing of its own that isn't compatible with any theory.
>Lead does not react to magnetic fields, and do you even have proof of Cavendish not taking into account electrostatic charges?
There's a thing called electrostatic attraction - using lead is silly.
>lead to gravitational-like forces during all his experimental runs?
The experiment that he watched using a telescope looking through a hole in a barn door? Ridiculous people believe this nonsense.

>>10122943
>T-the experiments are done perfectly and everything is taken into account even though I've never verified or observed these experiments

>>10122968
This. I'm floating into space as we speak.

>>10122276
irony or serious? do magas really hate science that much? why?

>>10122276
>dumb president poster

Isn't "time" just measuring the movement of matter within the universe?

>>10122917
All the evidence indicates that the gravitational coupling constant has not changed by more than a part per million since the birth of the universe.

>>10121137
I refuse to read through this idiot troll thread to see how long it took one of you to mention magnets.

>>10122679
www.google.com

Yes.

>>10122861
Ask me yesterday.

>>10122881

>>10122968
>Upper case T

Lurk fucking moar.

>>10123368
remember tomorrow

>>10122958
>et you are certain that gravity isn't a form of electromagnetism
There have been dozens and dozens of attempts to unify or eliminate gravity in theoretical physics. None have been successful. If you think you are smarter than everyone else than I encourage you to publish and go down as one of the greatest minds this species has ever produced.

>>10122905
but what if two people on opposite sides of earth jump off a building? is earth expanding in both directions that way? will it break theoretically

>>10122968
I did the Cavendish torsion balance experiment myself in my freshman physics class, am I a part of the conspiracy too now?

>>10126109
Yes

>>10122679
Try standing close to your mom and see if you don’t get pulled in

>>10126398
But don't cross the event horizon

>>10125153
no, that's what OP's pic is for
spaceTIME is bent inwards
remember that includes time
staying still (geodesic) means you would move inward relative to the earth's surface

>>10121149
No it visualizes a 1D plane you need a dimension for time and then a dimension to curve it

>>10122572
I like it but how?

>>10122988
Because most "scientists" are bought out lapdogs with a political agenda

>>10128159
Yeah, spacetime is a hot topic in politics.

>>10122679
You're standing on it.

A big old Mass, attracting yo ass.

>>10128204
Oh yeah? Why do the Australians need ground harnesses then?

>>10121137
I look at gravity as being kind of a 3d surface tension, except in a volumetric space rather than a planar one.

>>10121137
So what happens when you make something so heavy it rips the fabric?

>>10128241
You get a black hole

>>10128244
You get something weirder that I don't think has a physical analogue. If something too massive rips a hole in it, it suddenly stops attracting things but anything that gets too close to it just vanishes.

>>10121141
Think of the 3D space being 'stolen' and condensed into matter, leaving a stretched pit around it.
That's how I visualize it anyway.

>>10128291
>>10128244
>>10128241
Isn't the idea that it could rip flawed because our experience with material is that it can rip? What evidence is there that the fabric of space and time can rip?

>>10128387
Yes, it's flawed. The closest analogue would be a very dense object that stretches the fabric to infinity. Which would be a black hole.

Gravity visualized.

People need to start explaining this shit in highschool so you guys don't have to ask questions about it.

Forward on a piece of paper moves forward but if you bend the front downwards, then moving forward on the paper is still moving forward but in reality you are also moving downwards relative to other observers who see the paper bent downwards.

>>10128558
Well, the curvature of that piece of paper would be 0, so it's not a good example

>>10121137
Thank you.

>>10122679
Yes! You can even watch it happen in a lab with a sensitive torsion balance and some lead spheres.

>>10121137
As others have said, the demo relies on gravity to work.
So, how could you get it to work without gravity? Would one way be to have the material constantly 'flowing' into a central hole? Would that be representative of a real phenomenon?

>>10128684
Time dilation causes "temperature" differences in an object, and part of an object with higher temperature push part with lower closer to gravity well.

>>10128725
https://www.youtube.com/watch?v=gcvq1DAM-DE

>>10122572
Sounds like the holographic principal to me anon.

>>10122795
How can you believe in general relativity but not the special relativity it contains?

>>10128244
>>10128291
>>10128359
>>10128387
>>10128395
You got to add a layer of abstraction and think of the infinite tablecloth not as a flat plane but as the surface of a shape. For the simpler one, let's say a sphere, where energy deforms toward the center of the sphere (the big bang, where all the energy is concentrated) because deeper = more energy. Ripping a hole in it, means making the shape look like an apple, and opening a wormhole to the antipodes of the universe. Then it just becomes a topology nightmare.
That's what people mean when they speak of the wacky headlines "science men believe universe could actually be a donut".
And before anyone makes the jump to it, not not every black hole is a wormhole, you can bend geodesics to create event horizons without punching a hole.

Fucking hell are there really this many people on /sci/ without any experience with GR? So many shit analogies and opinions flying around here even without the /x/ baiters

>>10121137
Space time is a mathematical abstraction pretending to be a physical thing. It is doomed to fail.

>>10121137
http://libgen.io/comics0/_0DAY21/1%20Non%20English%20Origin/A/Anselme%20Lanturlu%20%28French%29/Anselme%20Lanturlu%20-%20T13%20-%20Le%20Topologicon.cbr
here it is explained to you in detail in the form of a fucking comic
high school level stuff

>>10121142
It's pretty shitty.
I get what it's trying to say, but it misses any relevant audience.

>>10128558
Then you jam a pencil through it.

>>10128811
GR is wrong, and it doesn't fit with special relativity, which fits with QM by the way. SR: speed produces time dilation. GR: gravity is equivalent to the pseudo-force of a non-inertial frame of reference but an electric force applied the same way uniformly isn't(????), acceleration is what causes time dilation, not fundamentally speed(????), gravitational lensing isn't explained by simply refraction. All the tests for GR have such a big error margin with such small measurements you might as well throw the theory into the trash.

>>10122968
>literally an experiment that sophomore physics/engineering majors do at every university in the US

>>10129124
lol

>>10129130
Doesn't mean it proves "space time curvature".

>>10121137
It's a moot point, but it does show a 2D analogue to the 3D (or even higher D) working of gravity. It's a good intro, only a fool would pursue a degree in physics and take it literally, rather, use it to for the correct picture and model in your mind.

>>10129300
Nobody said that, brainlet

>>10129369
Then it's pointless brainlet.

>>10129381
Remind me, Anon. What was the point of the experiment again?

>>10129538
Literally none of what you said makes any sense. Please try being less autistic next time.

>>10129541
So you don't know. lmao

>>10121137
I've toyed with one of these before. Not how gravity works.

>>10129124
Nice try /x/ baiter, you've clearly heard a few physics words and misinterpreted a few explanations in your time

>>10122905
>this also explains why differently massed objects accelerate at the same speed
Hahahahahahaaaaaa!

>>10129538
"Mass" "attracting" "mass", by virtue of mass alone. What is causing that please?

>>10129653
>What is causing that please?
Me: Curved spacetime
You: No because reasons xD
Me: I'm waiting for your publication
You: Sorry I'm stupid. I don't know shit about gravity, I'm going back to /x/

>>10129691
>Curved spacetime
Is this a mathematical abstraction, or a real physical "thing"?

>>10129746
It's a model of the real thing

>>10129746
The maths that is identical to how you would describe mass curving spacetime makes predictions that we can test.
We have tested it, it's real

>>10129789
>the real thing
Where?
>>10129948
>We have tested it, it's real
Tested what?

>>10128395
>The closest analogue would be a very dense object that stretches the fabric to infinity.
Again, if you rip a hole, things are no longer drawn towards that point.

>the demonstration of the cause of gravity is a demonstration of earth's gravity pulling a ball down

why isn't this circular?

>>10130054
>looks at pic
>it's a circle

>>10121137
stupid gay demonstration.
retarded

>>10122855
pretty much this

>>10129975
Tested the predictions made by the maths that also describes how spacetime can warp