doesnt gravity defy thermodinamics?

[apoyusiken]

do i have to explain? imagine you put an asteroid in earths orbit. it will accelerate. 

[VoxelPrismatic]

it's called potential energy.

[starsmine]

2 hours ago, apoyusiken said:

do i have to explain? imagine you put an asteroid in earths orbit. it will accelerate. 

? If its in orbit, its not accelerating. 

[GarlicDeliverySystem]

12 hours ago, apoyusiken said:

do i have to explain?

yes.

[apoyusiken]

9 hours ago, starsmine said:

? If its in orbit, its not accelerating. 

yes. but imagine you put it in orbit so initially its not moving and then it starts to move.

[Avocado Diaboli]

12 hours ago, apoyusiken said:

imagine you put an asteroid in earths orbit.

How did you put it there? If you break thermodynamics by just having it appear out of nowhere and completely stationary (in as much as that's even possible, which it isn't), then you don't get to be surprised that the laws of thermodynamics get broken. You broke them. Also, you know, put a ball on a ramp. It'll roll down the ramp. What law of thermodynamics gets broken by that?

 

This sounds like a thread a teenager makes when they first encounter some new topic and immediately think that there's obviously something wrong with how everybody for the past century has been going on about things.

[apoyusiken]

16 minutes ago, Avocado Diaboli said:

How did you put it there? If you break thermodynamics by just having it appear out of nowhere and completely stationary (in as much as that's even possible, which it isn't), then you don't get to be surprised that the laws of thermodynamics get broken. You broke them. Also, you know, put a ball on a ramp. It'll roll down the ramp. What law of thermodynamics gets broken by that?

 

This sounds like a thread a teenager makes when they first encounter some new topic and immediately think that there's obviously something wrong with how everybody for the past century has been going on about things.

bro, i get what you mean but please dont dismiss what i mean right away. obviously you need energy to put a ball on a ramp. on the other hand how does helium rise to the sky? you can maybe explain this but gravity is innately a force that doesnt run out. if you put the objects near each other in space they will collide. and we use gravity to accelerate spacecrafts? do i have to come up with contraptions to exploit gravity? there is clearly something sketchy here. i am not saying science is wrong, im asking whats the catch and you immediately dismissing my question isnt very scientific.

[Avocado Diaboli]

1 minute ago, apoyusiken said:

bro, i get what you mean but please dont dismiss what i mean right away. obviously you need energy to put a ball on a ramp. on the other hand how does helium rise to the sky? you can maybe explain this but gravity is innately a force that doesnt run out. if you put the objects near each other in space they will collide. and we use gravity to accelerate spacecrafts? do i have to come up with contraptions to exploit gravity? there is clearly something sketchy here. i am not saying science is wrong, im asking whats the catch and you immediately dismissing my question isnt very scientific.

Yes, you need energy to put the ball on the ramp. That's the potential energy that gets released when it rolls down. Same way with your asteroid. If you don't just magic it into existence, then you'll need to exert energy to make it appear stationary relative to Earth within its gravity well. And you would need to do that indefinitely, because gravity, as far as we understand it, is just a fundamental part of how reality operates, that matter distorts spacetime which causes things to be attracted to each other.  I really don't see what's sketchy about any of this.

 

Also, helium rises to the altitude where all gases denser than it are below it and all gases that are less dense are above it. All the gases are still affected by gravity. If you don't think it is, explain your reasoning.

 

And the reason I'm so dismissive about this is that you really didn't put much effort into this thread, or any of your others. You just seem to write short stream-of-consciousness things that typically have a presumptive and arrogant tone about them. Even here, you pose a question in the thread title and then immediately think that that question itself makes complete sense without further qualification. "Do I need to explain?" Yes, you always need to explain, because we can't look inside your brain to see what misassumptions have led you to making statements like these. The best I can gleam from the few examples you've given is that you fundamentally still don't understand the basics of physics, but you think you do and found some kind of bug in the system, aka an example of the Dunning-Kruger effect.

[GarlicDeliverySystem]

27 minutes ago, apoyusiken said:

yes. but imagine you put it in orbit so initially its not moving and then it starts to move.

Yes, it will "fall" towards earth or wherever the curvature of space-time will bring it. However, the funny thing about relativity is that from the perspective of the asteroid nothing will change, only the earth will come closer.

 

8 minutes ago, apoyusiken said:

on the other hand how does helium rise to the sky?

Yes, that is called buoyancy and thermal motion. It takes more energy to bring something heavy "up" in a gravity well like earths atmosphere than it does to bring something lighter up. So the heavy stuff will go lower, displacing the lighter stuff which goes up. At the top of the atmosphere, the solar wind (charged particles and gas being shot out from the sun) is strong enough to knock individual helium atoms out of the very thin atmosphere. So Helium (and hydrogen as well) leaves the atmosphere for good.

 

9 minutes ago, apoyusiken said:

You can maybe explain this but gravity is innately a force that doesnt run out.

Gravity is not really a force, it is an apparent force caused by the curvature of space itself. I can't really wrap my mind enough around this to explain it properly, but it isn't like electrical forces or classic mechanics. It is more that the space itself isn't flat and the motion of things within it can be explained by an apparent force that we call gravity.

 

11 minutes ago, apoyusiken said:

and we use gravity to accelerate spacecrafts? do i have to come up with contraptions to exploit gravity? there is clearly something sketchy here.

There is roughly two possibilities here: either something is sketchy and everyone is in on it, or your understanding is just sketchy and things can be explained a lot better and make more sense than you think. I am not saying we know or understand everything (gravity on a very fundamental level is still not fully understood), but we do have enough understanding as a society to answer these questions.

[apoyusiken]

18 minutes ago, GarlicDeliverySystem said:

Yes, it will "fall" towards earth or wherever the curvature of space-time will bring it. However, the funny thing about relativity is that from the perspective of the asteroid nothing will change, only the earth will come closer.

 

Yes, that is called buoyancy and thermal motion. It takes more energy to bring something heavy "up" in a gravity well like earths atmosphere than it does to bring something lighter up. So the heavy stuff will go lower, displacing the lighter stuff which goes up. At the top of the atmosphere, the solar wind (charged particles and gas being shot out from the sun) is strong enough to knock individual helium atoms out of the very thin atmosphere. So Helium (and hydrogen as well) leaves the atmosphere for good.

 

Gravity is not really a force, it is an apparent force caused by the curvature of space itself. I can't really wrap my mind enough around this to explain it properly, but it isn't like electrical forces or classic mechanics. It is more that the space itself isn't flat and the motion of things within it can be explained by an apparent force that we call gravity.

 

There is roughly two possibilities here: either something is sketchy and everyone is in on it, or your understanding is just sketchy and things can be explained a lot better and make more sense than you think. I am not saying we know or understand everything (gravity on a very fundamental level is still not fully understood), but we do have enough understanding as a society to answer these questions.

actually then the answer is gravity doesnt exist? so i dont think my proposition was wrong? but still i dont fully get it and its relation with thermodynamics. it still seems like creating energy out of thin air

[GarlicDeliverySystem]

3 minutes ago, apoyusiken said:

actually then the answer is gravity doesnt exist? so i dont think my proposition was wrong? but still i dont fully get it and its relation with thermodynamics. it still seems like creating energy out of thin air

It does exist. General relativity is a thing, so is gravity. Just because the understanding might be flawed or how we think/talk about it, doesn't mean the earth suddenly decides to no longer go around the sun.

 

And I don't see the relation with thermodynamics you are trying to make here. In terms of thermodynamics, something like an asteroid in orbit would have kinetic and potential energy. You willing it in existence created that energy. So yes, it did create energy out of thin air because we created an asteroid out of thin air with energy associated with it.

[wasab]

No, it does not break the laws of thermodynamics. every bit of kinetic energy it gains through gravity would have to be repaid in order to escape gravity. if an asteroid crashes into Earth due to Earth's gravitational pull, any energy it gained from gravity would then have to be repaid if this same object is to escape Earth and back into outer space again, never mind the fact it probably wont remain intact upon impact. 

 

That said, Gravity is not a force according to modern physics. Rather it is a phenomenon due to the wrapping of space-time. Acceleration is actually an illusion. The object did not accelerate; rather, it is Earth that actually accelerates and pushes up, but due to the frame of reference, we don't actually see it as such.

 

it is like how you are in an elevator as it accelerates upward. The elevator floor will then push up against you as it accelerates, creating gravity. note, i did not say artificial gravity because the force you experience due to acceleration is literally 100% the same thing as just gravity. THERE IS ABSOLUTELY ZERO DIFFERENCE BETWEEN THE TWO. you did not accelerate, rather the elevator did, and that force you felt is actually the elevator pushing up against you.

 

now imagine that elevator is in space, initially without acceleration, you will be floating inside the elevator. This means you are essentially in free fall inside this elevator.

 

now imagine this elevator then accelerates up, you then fall down to the floor as a result, as the elevator floor moves up against you. makes sense yes? but what if you have horizontal velocity before acceleration? Imagine you were traveling left to right inside this elevator before it accelerates. When acceleration happens, your horizontal trajectory becomes curved, it is as if you you traveling left to right but also falling down like a parabola.

 

You did not accelerate downward; you had zero vertical velocity, but as the elevator accelerated up, it gave off the illusion you were accelerating down.

It is just that, an illusion.

 

Gravity on planet Earth is the same thing. No acceleration down, rather Earth is accelerating up. gravity is actually an upward force, not downward. for earth's case, it is due to the wrapping of space and time. all objects are traveling in a straight line, just like an object in an elevator traveling horizontally is traveling in a straight line. However, due to the wrapping of space and time, their straight line is actually curved, giving you the illusion as if it is experiencing a force. 

 

This video is where I get the above information from.

 

 

[spacepickle]

4 hours ago, wasab said:

 

 

 

literally the first video I thought of

[wasab]

On 4/6/2025 at 3:00 PM, spacepickle said:

literally the first video I thought of

Yeah, it is a good vid. The main take away here is that if you jump off an airplane and are falling from sky, there is actually zero acceleration according to general relativity. No force is acting on you because  gravity isn't a force so you aren't actually accelerating just like a person itself isn't accelerating in an accelerating space elevator in space until that guy falls and touches the elevator floor.

 

 

Newtonian physics aka classical physics on the other hand would say you were accelerating at 9.81m per second squared due to gravity while falling but according to einstein, there wasn't a force acting on you, you did not accelerate as you fell, rather it was the earth coming up to meet you like an accelerating elevator came up to meet the person in free fall. 

 

Once you hit the earth, that's when you actually experience acceleration, earth/the ground push up against you and stop your fall. This is an actual force that you experience, not that illusion of gravity as you fell from the sky. It is this same force you felt inside an elevator as you impact the elevator floor. You don't experience any force until that floor actually pushes up on you and probably crashes your bone if it is 9.81 meter per second square like on earth. 

 

Try this fun experiment. Step inside an elevator and weight yourself. As elevator accelerated up, you would put on some weight because this acceleration creates a force acting on you. You can say elevator temporarily created a temporary gravity as the elevator floor pushes up on you and exerts a force. Your weight then becomes earths gravity plus the elevator's temporary gravity. After acceleration stops(except the necessary amount to prevent the elevator from slowing and falling back down of course), which is after a few seconds or so, both you and the elevator will be moving up at constant speed so the acceleration/weight you feel would be the same and equal to Earth's gravity, 9.81 m/s squared(elevator floor is pushing up on you at 9.81 m/s, it has to to match the downward force of gravity)

 

Now here is the interesting part, as elevator slows down, you are experiencing a force but in the opposite direction, down rather than up so you may actually experience something like an anti gravity! Weight yourself, you may suddenly lose some weight if you have a scale nearby, as it decelerates(okay, elevator did not actually exert a force downward, gravity takes care of that, it just exerts less force going up so gravity does the deceleration). 

 

Neat right? Now imagine this elevator suddenly cut lose. All cables snaps and broke and the elevator falls down due to earths gravity and you also fall with it. What do you think happens now? This "anti gravity" now is exactly the same as earths gravity so it is like the two perfectly cancel one another out. The elevator is no longer pushing up on you at all. you will become weightless

 

You are essentially in a free fall. You will be experiencing the same thing as an astronaut inside a space station orbiting outside earth. Everything will float around you inside this elevator as if gravity doesn't exist. If you have scale under your feet, it will measure that you have ZERO weight. 

 

You will continue to be weightless until this elevator crashes into the ground floor of the building and then you crash into the elevator floor and die a painful death. 

 

This is why physics is so counterintuitive but looking at it this way gives some intuition why gravity is actually an upward force, rather than downward. If you have no window inside a falling elevator, you wouldn't know you were falling down. From your point of reference, you would just be floating and weightless and that gravity doesn't exist.