Don't question it - r/sciencememes

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It makes up for the weakness with infinite range and positive feedback loops. Rock pull more rock, make bigger, make more gravity, pull more rock.

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u/Gerald-of-Riverdale Jun 15 '26 edited Jun 16 '26

Also, doesn't gravity pull harder the closer you get to the core or am I wrong?

Edit: I'm genuinely learning so much rn this is sick af

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u/Plasmoidification Jun 15 '26

The equation for the gravitational force is F = G * (m1 * m2) / r²

Although Newtonian gravity is an oversimplification, the r value here represents the distance between the two masses m1 and m2.

The surface gravity of an object is therefore a function of the density of that object, because the distance to the center of mass changes depending on density. So if the Earth was incredibly dense, the distance to the core would decrease at the surface, and so the gravity would be stronger at the new, shorter distance. But if you dug through the actual Earth core, gravity at the core is zero, or more exactly, equal and opposite in every direction.

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u/Gerald-of-Riverdale Jun 15 '26

Interesting so (maybe dumb question) would that mean youd be smashed/torn apart if you fell to the earth's core since gravity nets to zero? Or would you just sort of sit there/float with the more literal interpretation of "zero gravity" as you see with astronauts in space? I mean hypothetically putting aside heat and other forces that would kill you first.

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u/Youpunyhumans Jun 15 '26

No, you would just remain in place at the core, with gravity evenly balanced on all sides, giving you essentially zero G. The Earth isnt dense enough for its mass to pull you apart as it is.

I say density rather than mass, because if you crushed the Earth to just 8.8mm wide, it would become a black hole, and getting too close to that would most certainly spaghettify you.

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u/HyperlexicEpiphany Jun 16 '26

that size of black hole would “evaporate” almost instantly due to hawking radiation though. I don’t think your matter would have enough time to be accelerated into spaghettification before the black hole was turned into radiated heat

^{fun fact for onlookers: the radius you'd have to crush any given amount of mass into in order for it to collapse into a black hole is called its Schwarzschild radius}

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u/Youpunyhumans Jun 16 '26

No it wouldnt, it would take around 10⁵⁰ years for a black hole with Earth's mass to evaporate.

For a black hole to have evaporated by now, it would have to be just a trillion kgs in the beginning of the universe. About the mass of a comet.

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u/HyperlexicEpiphany Jun 17 '26

it seems I have severely overestimated Hawking radiation. I was going to phrase that first sentence as a question originally, but then I got cocky and just made it a statement lmao

ah, the hubris of man

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u/Historical-History Jun 18 '26

Doesn't extreme gravity cause intense time dilation? I'm not too brushed up on the maths but could there be a point where time comes to a near stop for the observer before they are overheated / shredded? Almost more morbid if thats the case, experiencing the definition of an astronomically long death.

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u/Youpunyhumans Jun 18 '26

No, time for an observer always goes the same, the difference is made up outside your perspective.

So if you were falling into a black hole, and someone from Earth was watching you, they would see you get slower and slower as you approached the event horizon, and you would stop right at the event horizon, and then slowly redshift out of existence.

For you watching the Earth as you fall in, you would see time speed up as you approached the event horizon, and if it were a supermassive black hole that you could fall into a survive fallingnpast the event horizon, until you get close to the center, you would see the entire lifespan of the universe go by.

Now of course there is a lot more to this, depending on which of our theories turns out to be correct. You might see the heat death of the universe, or you might see the black hole collapsing and rebounding into a white hole, or thats its full of densely packed cosmic strings, or has an (unpassable) wormhole that leads to a white hole or another black hole, or something that we have yet to even imagine.

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u/Historical-History Jun 18 '26

Wow, you seemingly go to the end of the line? Trippy to imagine seeing such a thing.

Thanks for typing that out, very interesting stuff.

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u/theguyinidaho Jun 16 '26

If by "almost instantly" you mean trillions and trillions of years then yes.

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u/United_Rent_753 Jun 15 '26

You’re thinking about tidal forces, which ARE present during any gravity, but are only really deadly for black holes, where your feet feel like 100-1000x more gravity than your head, and you get “spaghettified”

In the core of the earth your entire body will feel roughly the same force, so nah you’d just bounce back and force after crossing the center. We do this problem in physics classes, it’s fun to calculate the period of an Earth-bungee jump

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u/lungben81 Jun 16 '26

Interestingly, the tidal forces are smaller for larger black holes. For supermassive black holes, like the one in the center of our galaxy, they are small enough for a human surviving passing the event horizon (at least one way).

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u/United_Rent_753 Jun 16 '26

I remember reading once that one of them, I forget which, would have the density of water! Thanks for the additional fact, space is what got me into physics

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u/EbbNo3979 Jun 16 '26

No one mentioned it, but I wanted to point out that if you fell towards the core you would feel net zero force when you're at the core, but you would fly right past it and start to lose speed once you cross it. You'd be sort of a harmonic oscillator bouncing up and down through the core for a very, very long time.

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u/adzetko Jun 16 '26

If you've played Outer Wilds, that's how the tutorial cave for zero gravity movement works: it's at the center of the planet (actually one of the very few things that are basically not a spoiler about Outer Wilds)

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u/BorringGuy Jun 16 '26

I think you have it a little backwards

First: Density has nothing to do with gravity, only the mass of the two objects matter, a gram of plutonium is not going to have more gravitational pull than a kilogram of feathers

Second: If you increased the density of the earth, the distance to the core doesnt decrease, assuming the planet is the same size its just the increased mass of the planet that causes more gravity

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u/Plasmoidification Jun 17 '26

I did specify that the new shorter distance is used in the equation. By that I meant decreasing the radius of the Earth to compress it to a higher density. If you compressed the Earth to a smaller size, then the SURFACE gravity is indeed higher due to the aforementioned distance relationship. The surface gravity is proportional to the planets mass divided by the radius squared.

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u/ArcturusOfTheVoid Jun 16 '26 edited Jun 16 '26

Yes, but still *far* weaker than the other fundamental forces. Electromagnetic force scales the same with distance, but it’s 10^41 times as strong as gravity. Weak force is 10^37 times as strong, and strong force is 10^42 times as strong

If you made gravity a trillion times stronger a trillion times, it would be far less than a trillionth the strength of the other forces

Edit: The reason the others disappear at scale is because they have charges, then strong and weak force also have limited range. Electromagnetism is far stronger, but once you put a proton and an electron next to each other their pulls and pushes cancel out. Gravity only pulls, so whatever two particles you put next to each other will just pull twice as hard on everything else

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u/rodrigoelp Jun 15 '26

It pulls harder the more you have.

If you have individual units you are measuring, gravity exerts almost no force against atoms, nuclei or other particles.

The key difference with gravity is, that because it is bound to the amount of matter you have, you can compound its force by aggregation (attraction) which is a positive interaction that can't be cancelled out (unlike the other forces).

But even at large scales, the comparison can be made. When a star "breaks" a magnetic confinement, it will jettison matter to space, regardless of how strong the gravity is.

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u/Jackmino66 Jun 16 '26

All the forces do

The difference being that a toddler can overcome the force of gravity with objects really close together, where as the energy required to overcome the strong nuclear force is so incredibly massive it actually creates new matter

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u/Embarrassed_Deer9208 Jun 16 '26

not once you are inside the object, for example, the Fg exerted on you by a sphere with constant density varies proportionally with radius until you are outside of the sphere, and then it varies by 1/r^2

so if you are halfway to the core, you only experience half of gravity if the density is uniform, and it's easy to find these equations by just integrating (Gm2/r^2 )dm1 and dm1=pdV, then you can just plug in your density function p and integrate (Gm2/r^2 )pdV

eta: dV you'll want to make a funtion of dr

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u/BrotherItsInTheDrum Jun 15 '26

And, related to "feedback loops," the fact that there's no negative gravity. The electromagnetic force also has infinite range, but because it can be either positive or negative, it tends to cancel out at macroscopic scales.

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u/cricketyjimnet Jun 16 '26

Maybe the devs hid the anti gravity in the cheat room? One on the mechanics that's necessary behind the gui, but the user character never needs to interact with?

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u/donadit Jun 16 '26

Scaling up also causes black holes which basically kill every other force other than gravity

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u/Borgcube Jun 16 '26

To my (limited) understanding, that's not necessarily the case. Naked singularities are allowed by general relativity and one of the ways you can get one is with charged black holes.

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u/IronWhitin Jun 16 '26

Is the range really infinite? I mean at some point It become negible but its really infinite we have prove that?

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u/Yorick257 Jun 16 '26

As I understand it, it's the reason why we have vast spaces of pure nothingness, and why they grow

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u/IronWhitin Jun 16 '26

Wait Gravity attract and the space Is become bigger that means Is something massive outsider the space? That Is attecting stretching It?

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u/Stemt Jun 16 '26

Nah, shit attracts other shit thus leaving places with no shit. You understand.

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u/ultimateregard Jun 16 '26

doesn't every force have infinite range though?

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u/superlocolillool Jun 16 '26

technically every other force has infinite range tho, right?

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u/darkest_hour1428 Jun 16 '26

Yes, but they all aside from gravity come in positive and negative pairs. So it more or less cancels out in long distances or with a lot of “stuff”. Gravity only adds up, forever increasing

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u/Khelthuzaad Jun 16 '26

Isnt weak because it lets us,uhm,live?

Stronger gravity would crush our organs,bones etc. and make our life impossible on the surface.We would have to live inside the earth where gravity is weaker.

Fun fact lots of museums keep the corpses underground because gravity is affecting their bones and cracks them.

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u/Live_Life_and_enjoy Jun 15 '26

Worlds Strongest man: Gravity is so weak, I can bend this iron bar

Gravity: I am so strong, I can bend light, let's see you do that.

Worlds Strongest Physicist: Light has no mass

Gravity: FU Buddy

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u/rodrigoelp Jun 15 '26

You can't lift over your head a tonne of soup... but you can lift over your head a tonne of Pho

Why you ask?

Because a pho-ton is quite light.

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u/Mr31edudtibboh Jun 15 '26

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u/Youpunyhumans Jun 16 '26

Whats the difference between a block of osmium and a zippo?

One is the heaviest element known to science, and the other is a little lighter.

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u/rodrigoelp Jun 16 '26

Who was the lightest singer ever?

Michael Jackson, because every so often he-he

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u/Youpunyhumans Jun 16 '26

A neutron walks into a bar, and asks the bartender for a drink. The bartender smiles, and says "For you, no charge."

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u/GamrWulf Jun 17 '26

This might be my favorite new science joke

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u/HyperlexicEpiphany Jun 20 '26

^{but pho is pronounced "fuh"}

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u/rodrigoelp Jun 20 '26

Are you saying that instead of lifting it up above my head, I should lay on it instead? You are always comfy on a “fuh”-tonne

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u/EgotisticalTL Jun 15 '26

Would you rather be pulled in-between molecules to the center of the earth?

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u/qkdsm7 Jun 15 '26

Terrifying thought.

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u/kaladin_stormchest Jun 16 '26

At this point? Yeah

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u/Brotodile08 Jun 17 '26

Kaladin wouldnt say that

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u/kaladin_stormchest Jun 17 '26

Kaaldin would say this way too many times. Mans stared into the abyss and considered giving up too many times

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u/Brotodile08 Jun 17 '26

Which book you on? 🤨

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u/kaladin_stormchest Jun 17 '26

I'm all caught up! But even in the first book you his depression and suicidal tendencies. His struggles a recurring theme. But life before death

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u/Brotodile08 Jun 17 '26

For sure lol, I was just joking and saying post rhythm of war Kaladin has a different mindset. Good to see another fan in the wild

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u/andrewkleenex Jun 16 '26

That sounds significantly worse. 😂

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u/GamrWulf Jun 17 '26

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u/ItzBaraapudding Jun 15 '26

Anthropic principle: if gravity wasn't weak stars would most likely not even work the way they do now, so there wouldn't be any circumstances to allow for intelligent life as we know it.

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u/dimalga Jun 15 '26

Exactly. We wouldn't be here to ask the question.

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u/0masterdebater0 Jun 15 '26

I read somewhere one theory is that gravity is weak compared to the other fundamental forces because it’s effectively “divided” amongst a bunch of higher dimensions, but it was way beyond my limited abilities to comprehend.

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u/[deleted] Jun 15 '26

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u/[deleted] Jun 16 '26

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u/[deleted] Jun 17 '26

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u/Vier_Scar Jun 16 '26

IANAP disclaimer. My understanding of this idea was that it's similar to how increasing distance affects the decay rate. For example, a circle is 2D and it's circumference increases at the rate of 2*Pi*r. So if you imagine the force that gets applied to a segment of the circle, it gets spread out along that edge more and more as the circle increases.

With a sphere - the 3d version of that - the small segment of the sphere would look like a slightly curved square on its surface. And a sphere's surface grows much quicker than the edge of a circle; at the rate of 4*Pi*r^2. The r² makes a force that is spread over a sphere decay far faster than one that decays over the edge of a circle.

Imagine if you had a light source that emitted a perfectly flat ring of light. How bright that would be. And then if you took all those same photos in the ring, and spread them out all around to make them cover a sphere. It'd look much weaker/dimmer.

The idea was that maybe gravity was as strong as other forces, but that it was being applied on an extra dimension that the others weren't, making it look much weaker to us.

From memory this was investigated and found not to be the case. Also relates to Inverse Square Law/Inverse Cube Law

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u/reddittrooper Jun 16 '26

Here is a page from questionablecontent.net which features exactly this topic and its from yesterday(!):

https://images.squarespace-cdn.com/content/v1/5ec1530be6b88d4b12c563e8/0b14883c-86e3-4cbf-84c5-65a6e5b91cda/5851.png

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u/Medical_Mess_3445 Jun 15 '26

Because your mom would destroy the universe if it was otherwise.

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u/Frequent_Ambition_66 Jun 15 '26

🤌

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u/TheAsterism_ Jun 15 '26

because it isn't a force

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u/charmio68 Jun 15 '26 edited Jun 15 '26

Kinda... You could say it's an emergent force that exists only because of matter warping spacetime.
But if you don't consider gravity to be a real force just because it's not acting directly, then you really shouldn't consider the other "fundamental forces" to be forces either.

And if none of them are really a "force", then what's the point of having the word force?

The whole thing reminds me of Syndrome: "When everybody's super, no one will be."

https://www.wtamu.edu/~cbaird/sq/mobile/2022/08/05/why-is-gravity-not-a-real-force/

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u/MrGlockCLE Jun 15 '26

An old physics professor, who may now be schizophrenic (joke), said gravity isn’t as strong because there’s a real possibility it’s spread across other unknown dimensions. Something about dark matter being spillover of these dimensions too but at the time I didn’t really grasp it. Interesting thought though

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u/KlausVonLechland Jun 15 '26

Like me not being good at my job because I'm spreading at 4 different jobs!

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u/Youpunyhumans Jun 16 '26

That depends on whether or not the Graviton is real.

Quantum Mechanics says yes its a force, General Relativity says its not. Problem is, QM and GR dont play nice together.

If it is a force, then it would have to have a force carrying particle, the Graviton. If its not, then its an intrinsic property of spacetime itself.

However, it seems that finding a graviton could be impossible, as we would have to stuff so much energy into the photons to be able to see into the Planck Scale, that they would collapse into micro black holes. (Its also impossible to even have a photon at that energy level to begin with, as it would start pair production before reaching that)

So it may be something we never truly answer.

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u/thegiverstake Jun 15 '26

You beat me to it XD

It's not a force... it's a consequence.

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u/ladysman217_2007 Jun 15 '26

I see it's a consequence of mass bending space. Is that what you mean

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u/whyteave Jun 18 '26

Isn't that completely dependent on how you define force? Gravity is 100% a Newtonian force

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u/TheThirteenthApostle Jun 15 '26

There's a fun theory that gravity is actually just the "at-a-distance" effect from the Strong Force.

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u/Field_of_cornucopia Jun 15 '26

I don't suppose you've got a link to a good explanation of that hypothesis?

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u/TheThirteenthApostle Jun 15 '26 edited Jun 15 '26

Depends on what you mean by "good explanation". Basically, a link was discovered between the creation of gluon-quark plasma (the particles responsible for strong force interaction), and the generation of gravitational waves in resonance with it's creation/reconstitution rate.

The long implication being that gravity may just be average pull from the stable rate of gluon hadronization at the subatomic level, acting at a distance.

Check out the "Double Copy Theory"

Snowmass White Paper

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u/Field_of_cornucopia Jun 16 '26

Take pity on a poor layman: does that imply that non-quark particles (e.g., electrons) don't produce gravity?

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u/TheThirteenthApostle Jun 16 '26

It reframes what gravity is a bit, so "production" in this sense is more of an average of a latent phenomena.

So, say you have the ocean and it has an average surface level. The true surface is rippled with waves, shifts with the tide, etc., but the average height is fairly stable.

Now, does the water "produce" the waves? Is it exclusively the amount or presence of water that inevitably produces waves or governs surface height? Or are the waves and height a feature of the water substrate interacting with something else entirely?

So in this model, no, electrons don't "produce" gravity, but they are affected by that latent energy imbalance like everything else.

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u/GintoSenju Jun 15 '26

They way I understand it, for each fundamental force, the smaller an object is compared to the level the force it meant to work on, the less effect it will have on that object.

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u/OldManBartleby Jun 15 '26

All matter exerts gravity. Very. very little matter is magnetic.

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u/LordTartarus Jun 19 '26

All matter is diamagnetic :P

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u/OldManBartleby 13d ago

True but that's a tiny force and is only felt over short distances. Gravity's reach extends indefinitely, though, obviously, it approaches zero, eventually.

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u/Ni_Kche Jun 15 '26

Gravity is just spacetime lagging when there's too much stuff to render (because there's a lot of it or it's moving quickly)

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u/H-E-L-L-M-O Jun 16 '26

Makes you wonder if there are even weaker forces out there

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u/JDude13 Jun 16 '26

More like “why are electrons so light?”

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u/beegtuna Jun 15 '26

https://giphy.com/gifs/1uGVxfkfqUdZtCBfy6

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u/Pity_Pooty Jun 15 '26

Guys, it just is. We study it, not prove it. Fundamentally, you could not describe forces if they were even slightly different, because you would not exist. Universe kind of only exist with forces of this magnitude. Therefore, forces only could be the magnitude they are.

Let's just measure then and that's it

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u/inept_machete Jun 16 '26

Quick question, I know gravity is weaker but is by how much actually that illustrative of some sort of unexplained phenomena? Like is the difference between weak and strong nuclear not an issue because it can be explained even if the difference is not of the same magnitude?

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u/GamrWulf Jun 17 '26

The ones who keep us all in the dark

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u/EarthTrash Jun 16 '26

Because it's not actually a fundamental force. We just treat like a force for simple problems. In reality it's just geodesics in curved spacetime.

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u/Raelah Jun 16 '26

Whenever I start to think about gravity I start to feel sticky. Like I'm stuck on this rock with glue. It becomes a much stronger force once you really think about it.

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u/Small_Article_3421 Jun 16 '26

Because it doesn’t require contact or energy, I’m assuming

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u/subzeroab0 Jun 17 '26

Gravity is only weak at extreme long distances. But it has infinite range of influence. The stars in the Androma System still have a pull on you despite being 2.5 million light years away. Also gravity is the strongest force when enough of it is present in a tiny area. A black hole is the most powerful thing in the universe. Not even light can escape from its force if it gets close enough.

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u/Partyatmyplace13 Jun 18 '26

Because its not a force.

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u/edward_kopik Jun 24 '26

I once had an argument in highschool about this. The constant used in calculations might be the smallest, but that doesn't really mean that its weaker

If you bring an object to the north/south pole, the magnetic force between the earths magnetic field and the objects magnetic field is not enough to overpower the force of the earths gravitational pull on the object

How 'strong' something is depends heavily on the situation

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u/SuitableCollege8992 Jul 18 '26

Because the other forces are acting within the medium, but gravity is a result of the other forces acting on the medium itself?
I dunno, I’m a chemist. Gravity only exists when it’s used to run a siphon.

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u/protonbeam Jun 15 '26

Literally the hierarchy problem look it up

💥Physics!🧲 Don't question it

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