/sci/ - Science & Math

[Anonymous No.6347979]

Do you even know how gravity works?
Explain it. Right now. Right now, three seconds. Explain gravity.

[Anonymous No.6347991]

>>6347979
Law of universal gravitation

[Anonymous No.6347993]

>>6347979

It's sad when people they don't relies they are stupid.

https://www.youtube.com/watch?v=wMFPe-DwULM

[Anonymous No.6347997]

f=G*m1*m2/r^2

[Anonymous No.6348002]

>>6347979
Mass bends spacetime; this attracts other masses because Reasons.

[Anonymous No.6348001]

>>6347997

[Anonymous No.6348005]

>>6347997
Do you remember what the constant is though? No google.

[Anonymous No.6348010]

>>6348005
6.022x 10^12? m^3/kgs^2

[Anonymous No.6348021]

>>6348010
Opposite end of the universal scale, remember little atoms = little force: 6.67 E-11

[Anonymous No.6348026]

>>6347997
boom. lrn2physics op

[Anonymous No.6348032]

>>6348021
6.022 x 10^23 is Avogadro's number which I always think of when remembering the gravitational constant.
Truth is I haven't had G show up in a calculation since high school, maybe freshman physics which was 6 years ago now.

[Anonymous No.6348036]

>>6347997
This is merely a description of the behavior of gravity (classically)

not an explanation of _how_ it works

>>6347979
Our best theory that attempts to describe _how_ gravity works is general relativity.

[Anonymous No.6348040]

>>6348032
Yeah, not much use for it past high school physics in general life unless you actual go into a field that requires it, and even then we can always use Google.

[Anonymous No.6348047]

>>6348036
It's because all the matter is lonely and wants to be closer to each other. Duh.

[Anonymous No.6348057]

>>6348047
>mfw this turns out to be the real answer

[Anonymous No.6348065]

>>6348036
pedo is right

[Anonymous No.6348066]

The downward motion of heavy bodies is a consequence of their nature. All objects fall towards the centre of the universe, which is below the earth, as it is their natural place. Light bodies, such as fire and air, naturally tend towards the heavens, as they are divine (man has no control over them).
Prove me wrong.

[Anonymous No.6348070]

ha that scene cracked me up. he was being such a dick

[Anonymous No.6348072]

>>6348057
And dark energy is the eternal loneliness tearing it all apart.
>tfw

[Anonymous No.6348074]

Every time I hear his voice I think of that one kid from that Polar Express movie.

[Anonymous No.6348079]

>>6348074
try replying to someone by clicking on the numbers in their comment and leaving the extraction symbols and the numbers there so we know who you are replying to all the time.

[Anonymous No.6348096]

>>6348047
This, I've also come to this conclusion based on very specific scientific study.
[spoiler]Dropping acid.

[Anonymous No.6348102]

>>6347993
>relies they are stupid
>relies they are
>relies they
>relies

[Anonymous No.6348106]

>>6348066

Why don't australians fall off the earth then.

[Anonymous No.6348109]

[Anonymous No.6348119]

Zach cannot be stopped, his power is too strong

[Anonymous No.6348118]

>>6348036
GR is no more a description of HOW than Newtonian gravity. It's just a more complex mathematical mechanism. One says mass creates force. The other says energy density creates spacetime curvature. Neither says how that creation happens. Nothing in physics can ever give an ultimate how. Ultimately it will always rest on some mathematical model that doesn't itself have a reason.

[Anonymous No.6348165]

>>6347979
Invisible wires bound to every object in the universe making them not spread apart, aka string theory

[Anonymous No.6348170]

>>6348118
But that's exactly the difference between a theory and a law.

The "Law of Universal Gravitation" is a law precisely because it is just a description of what happens.
That equation never says that mass creates gravity, it is merely a statement about what we observe, and we observe that the gravitational force is proportional to mass.
That's not a mechanism.

GR is a "theory" precisely because it is an attempt to provide a mechanism.
>Nothing in physics can ever give an ultimate how.
That's why theories do not become laws. You can't ever prove a theory.
On the other hand, laws will always hold some level of truth. If the law of universal gravitation is not exact, it will still be an adequate approximation at low energies for example.

[Anonymous No.6348399]

>>6348002
>What is stress-energy tensor?

[Anonymous No.6348405]

>>6347979
>Explain it. Right now. Right now, three seconds. Explain gravity.

inertial mass ≡ gravitational mass ⇒ gravitation is equivalent with a curved space-time were particles move along geodesics

[Anonymous No.6348443]

>>6347979
Nobody knows how gravity works

[Anonymous No.6348451]

Imagine Maggie Thatcher in a room with people around her. Then the god particle creates mass and so everything tries to stick together.
Source: I'm a gravitologist

[Anonymous No.6348454]

Mass attracts mass

[Anonymous No.6348475]

Gravity is just another form of magnetism.

[Anonymous No.6348482]

Gravity is just a theory (a guess)

[Anonymous No.6348483]

all atoms have invisible rubber bands glued to them

[Anonymous No.6348499]

gravity is undetectable anti-particle magnets

[Anonymous No.6348501]

space foam trampoline

[Anonymous No.6348505]

>>6348170
The law of gravitation is just an equation in a theory by Newton. There are laws within general relativity.
>That's why theories do not become laws.
No, it's not. The problem is an epistemological one, not a semantic one. Laws can also not be proven. The law of gravitiation as well as many other fundamental laws are approximations for special cases, obtained after truncating and neglecting left and right, you learn these derivations in the first semester.

[Anonymous No.6348509]

>>6347979
You are not looking for the how (mass bends spacetime, etc.), but for the why. Science does not aim to explain the why. It is the field of spirituality. Therefore, this topic is not really suited for /sci/ imo

[Anonymous No.6348524]

The earth's spinning holds us down to it; the sun spins even faster and is bigger so the earth floats around it also. For example mars doesn't spin so that why it has no atmosphere and gravity to hold the atmosphere it did have to it.

[Anonymous No.6348532]

I've only 1 year of calculus based physics survey, (pleb mathematician to le pays overlords) but would it be an appropriate abstraction to view gravity as a sort of matter detector (within the scope of the inverse square of distance)?

<span class="math">
If gravity is a field, and it comes from something, it would have to come from some kind of matter. This would induce a gravitational field in an initial state \[Gamma]. This signature \[Gamma] would be directly proportional to the density of the object, scaled by the quantity of matter of our \[Gamma], assuming the object is in isolation.

Then if \[Gamma]' =! \[Gamma] after an arbitrary interval of time, then there would exist a \[Delta] in the system not present at the time of observation of \[Gamma].

The signature of our delta would be crossed with gamma, and we could retrieve data on what delta might be via the analysis of \[Gamma]'.

Sorry if that's a terrible treatment, but would those assumptions be correct? First time I've though about gravity since mechanics 3.5years ago.[/spoiler]

[Anonymous No.6348587]

>>6348532

>forgot le rest xD
<span class="math">
If gravity is a field, and it comes from something, it would have to come from some kind of matter. This would induce a gravitational field in an initial state \[Gamma]. This signature \[Gamma] would be directly proportional to the density of the object, scaled by the quantity of matter of our \[Gamma], assuming the object is in isolation.

Then if \[Gamma]' =! \[Gamma] after an arbitrary interval of time, then there would exist a \[Delta] in the system not present at the time of observation of \[Gamma].

The signature of our delta would be crossed with gamma, and we could retrieve data on what delta might be via the analysis of \[Gamma]'.

Sorry if that's a terrible treatment, but would those assumptions be correct? First time I've though about gravity since mechanics 3.5years ago.[\math][/spoiler]

[Anonymous No.6348590]

>>6348587
>>6348532

fuck the scripts, i just need my point across

If gravity is a field, and it comes from something, it would have to come from some kind of matter. This would induce a gravitational field in an initial state [Gamma]. This signature [Gamma] would be directly proportional to the density of the object, scaled by the quantity of matter of our [Gamma], assuming the object is in isolation.

Then if [Gamma]' =! [Gamma] after an arbitrary interval of time, then there would exist a [Delta] in the system not present at the time of observation of [Gamma].

The signature of our delta would be crossed with gamma, and we could retrieve data on what delta might be via the analysis of [Gamma]'.

Sorry if that's a terrible treatment, but would those assumptions be correct? First time I've though about gravity since mechanics 3.5years ago.

[Anonymous No.6348633]

>>6348590
>fuck the scripts
yes, reading instructions is so hard xD

[Anonymous No.6348647]

[Anonymous No.6348712]

>>6347979
Mass distorts spacetime. This distortion of spacetime affects the inertial paths (paths of maximum proper time) that objects can travel relative to a massive body (in the absence of additional forces).

[Anonymous No.6348830]

>>6348505
>Laws can also not be proven.
They don't need to be proven because they are descriptions of what we observe, that was my point.

when I said this
>laws will always hold some level of truth. If the law of universal gravitation is not exact, it will still be an adequate approximation at low energies for example.
I already accounted for what you said about a lot of classical laws turning out to be approximations, because they can will always be useful within the domain that they were originally formulated because within that domain it was merely a description of what was observed, and that's never going to change unless the laws of physics change.

Theories on the other hand are an entirely different animal. Whether or not GR can give accurate predictions is not going to tell us if spacetime is actually bending or not, that's a theory. It provides a mechanism.

The difference is that GR is not a mere description of what gravity does. It is a description of how something unseen behaves behind the curtain and gravity is a result of it.
That is totally different then just saying "the gravitational force is proportional to the constant G, the mass of the two interacting objects, and inversely proportional to the distance squared".

One is a description of the observation of how gravity behaves (what the strength of the force depends on), while the other provides a mechanism.
You should know the point I'm arguing isn't my own. This stuff appears in physics textbooks, and the difference between the law of gravitation and GR is actually often used to demonstrate the difference between a law and a theory. This is not about semantics, they are this way by definition.

[Anonymous No.6349734]

Isn't gravity explained by string theory?

[Anonymous No.6349980]

>>6349734
Supposedly, yes.
But string theory isn't really relevant for discussions like this until it can make at least one testable prediction.

[Anonymous No.6351581]

gravity is when things fall down

[Anonymous No.6352711]

>>6348647
It all makes sense now.

[Anonymous No.6352731]

>>6349734
I love how nobody in this planet knows that a theory is.

What a fucking retard you are...

[Anonymous No.6352741]

Does anyone have a link to the scene in Ops pic?

I cant open gattocakes youtube videos for some reason.

[Anonymous No.6352756]

>>6347979
Paraphrasing Feynnman: I cannot explain to you how gravity works in terms of something else you are more familiar with, because I do not understand how gravity works in terms of something you are more familiar with. It's one of the parts of our universe which you're going to have to accept, because the evidence says so, and from that we can explain a great many other things.

[Anonymous No.6352773]

>>6352756
That's a very ubiquitous quote isn't it?

[Anonymous No.6352781]

>>6352773
>>6352755
Samefag

[Anonymous No.6352874]

How about Van der Waals forces pulling all particles in the universe towards each other and when together as a clump (like earth) causing synergically greater pull called gravity.

[Anonymous No.6352922]

>>6347997
i've always wondered, wouldn't that mean that once i get really close to something (like holding a pen between my fingers, or just sitting on a chair for that matter) would mean the force would tend towards infinity (as r -> 0) and i wouldn't be able to let go anymore?

or do i then have to go down in scale and look at the distance and mass of the atoms which come closer to each other?

[Anonymous No.6354394]

>>6352741
Look for the other gravity thread.

[Anonymous No.6354426]

>>6348096
<span class="math">CLICK ME % Use Latex for spoilers on /sci/[/spoiler]

[Anonymous No.6354447]

>>6348066
Best post in the thread, hands down

[Anonymous No.6354495]

according to my favorite scientist neil the grass tyson :^) gravity works by objects bending spacetime

[Anonymous No.6354509]

>>6348712
How does mass distort spacetime?

[Anonymous No.6355369]

>>6348066
Then why do all objects fall straight down? Assuming the center of the universe is spherical (as it is the perfect shape), and it is under the middle of the earth, all objects that aren't in Jerusalem (the middle of the earth) would fall in an angle towards Jerusalem.

Besides, the turtles are under the earth.

[Anonymous No.6355836]

>>6354426
<span class="math"> STOP %nobody can know that this is how we send secret messages about how 0.999=1 [/spoiler]

[Anonymous No.6356193]

>>6352874
Vaan der Waals forces are merely the result of momentarily dipole movements in a molecule attracting opposite dipoles in surrounding molecules. Basically, a molecule isn't always completely neutral in terms of charge, since the electrons are not always in the same place at once, resulting in some parts of a molecule being slightly more charged than other parts.
On a massive scale, such as the "clumps" you describe, these electrostatic attractions balance out completely. Any effect it would have on surrounding bodies would be completely negligible.
As a few other people in this thread have mentioned, gravity occurs as a result of energy distorting spacetime, at least according to general relativity. This is a little difficult to conceptualize, but imagine two objects moving in a straight line, parallel to each other. These objects would eventually collide with each other, assuming there were no obstructions in the way. According to Newtonian mechanics, this is because of the force of gravity between the two objects pulling them together, causing them to deviate off from their "straight path". General relativity explains this differently, however. It explains that the mass, or energy of these objects causes the very fabric of spacetime itself to curve. The objects continue to travel in a completely "straight" line throughout space, but the curvature in spacetime created by the other object causes them both to travel in a spherical path, eventually causing their paths to intersect.
It's a somewhat difficult concept to understand, mainly because of how abstract and unintuitive the idea of "curved spacetime" seems to us. We're used to thinking of space as being static, unchanging - a nothingness that just facilitates the movement of objects. However, in actuality, it's a lot more complex than that.
It's pretty cool.

[Anonymous No.6356198]

>>6352874
Vaan der Waals forces are merely the result of momentarily dipole movements in a molecule attracting opposite dipoles in surrounding molecules. Basically, a molecule isn't always completely neutral in terms of charge, since the electrons are not always in the same place at once, resulting in some parts of a molecule being slightly more charged than other parts.
On a massive scale, such as the "clumps" you describe, these electrostatic attractions balance out completely. Any effect it would have on surrounding bodies would be completely negligible.

As a few other people in this thread have mentioned, gravity occurs as a result of energy distorting spacetime, at least according to general relativity. This is a little difficult to conceptualize, but imagine two objects moving in a straight line, parallel to each other. These objects would eventually collide with each other, assuming there were no obstructions in the way. According to Newtonian mechanics, this is because of the force of gravity between the two objects pulling them together, causing them to deviate off from their "straight path".

General relativity explains this differently, however. It explains that the mass, or energy of these objects causes the very fabric of spacetime itself to curve. The objects continue to travel in a completely "straight" line throughout space, but the curvature in spacetime created by the other object causes them both to travel in a spherical path, eventually causing their paths to intersect.

It's a somewhat difficult concept to wrap your head around initially, mainly because of how abstract and unintuitive the idea of "curved spacetime" seems to us.

We're used to thinking of space as being static, unchanging - a nothingness that just facilitates the movement of objects. However, in actuality, it's a lot more complex than that.

It's pretty cool.

[Anonymous No.6356206]

It's like when you lay in bed and a ball rolls to you, only the bed is made out of space-time

[Anonymous No.6356237]

>>6352922

The attraction between the pen and the earth is far greater than the attraction between your fingers and the pen.

[Anonymous No.6356241]

>>6348066
Prove yourself right

[Anonymous No.6356244]

>>6356237

i.e. there are more molecules attracting the pen in the direction of the earth, which are close enough to contribute to the force (as compared to, say, other planets, etc)

[Anonymous No.6356581]

>>6347979
Mass x density = bullshit equation
Gravity

[Anonymous No.6356582]

>>6347979
things attract each other, the more closer they're the stronger the attraction.

[Anonymous No.6357484]

>>6347991
>Using a word with the same root to define a word.
Did you even graduate high school?

[Anonymous No.6357487]

Gravity is a social construct.

[Anonymous No.6357505]

gravity has dimensions of mass squared over length?

[Anonymous No.6357901]

Something with 9.8

[Anonymous No.6357903]

>>6356582
>more closer
you need to be more better at your english

[Anonymous No.6358023]

>>6352773
>a very ubiquitous quote
no, it's only slightly ubiquitous

[Anonymous No.6358100]

>>6347979
http://www.youtube.com/watch?v=MTY1Kje0yLg
I'll just leave this here.

[Anonymous No.6359775]

"Gravity" means "seriousness" or "importance".

Example: "I don't think you understand the gravity of the situation."

[Anonymous No.6359796]

>>6358100
I always loved these "warped sheet" analogies.

>using gravity to explain gravity topmost kek

[Anonymous No.6359907]

When you let go of things they go down

Take that autist

[Anonymous No.6360042]

>>6356244
You can't have radius 0.
Small things have small mass.
When working with very small r, gravity is the weakest of the fundamental forces.

[Anonymous No.6360081]

>>6348036
_how_ about you suck my dick, nye.

[Anonymous No.6360254]

>>6354509
The universe has a sort of "symmetry" to things.

The Higgs Field breaks this symmetry, creating mass, which in turn creates gravity.

[Anonymous No.6361810]

>>6360254
What symmetry does the Higgs field break?

[Anonymous No.6362910]

>>6352731
Isn't theory another word for guess?