This thread is a fathom away from plunging into the abyss of mathematics, I would like to execute a strategical retreat.

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how did it get this complicated

I thought the answer was () (you divided the 0 in the middle and it splited into () )
#### abraker wrote:

Plus, what does a 4D cake even look like?? A 2D cake is pi*r^2, a 3D cake is pi*r^2*h, but the 2 shapes are different. The equivalent of a circle in 3D is a sphere, not some puny cylinder. Note: we can consider a cylinder as 2-2D objects: circles and a rectangle. So what is the combination for a 4D cake??

Cylinder + rectangular prism??(which is the equivalent of 2*circle*rectangle + rectangle*6 in 2D world). Cylinder + Sphere?

#### abraker wrote:

**radians** of a cake. Things need units depending on what you're measuring. For example, when measuring your dick, you would say x **dx** long. Now if you don't know what radians are, you obviously haven't played enough MMORPG to know what raids are, which means you should go play more. Now since I'm a nice person, I'll explain what radians are. It's basically a unit that we use to see whether we hit the G spot or not
#### Blitzfrog wrote:

#### Blitzfrog wrote:

#### ColdTooth wrote:

You can't divide by 0 because if you could you would be able to make a lot of contradictions.

Using real life examples is bad because you can do a lot of things in maths that don't work in real life.
#### silmarilen wrote:

#### silmarilen wrote:

BUT, If you were saying that certain things in math should be explained in a mathematical way then I agree with you.
#### Rifdi wrote:

#### Blitzfrog wrote:

#### Rifdi wrote:

First off, Blackholes don't have mass. Not directly. They're not anything, how can they have mass? Black holes are not objects, they're what happens when you delete a region from the fabric of spacetime. We just talk about them like mass because they, similar to a massive object, exert gravitatational properties to other objects. For example, replace the sun with a black hole the size of the schwartzchild radius of the sun, and nothing about the gravitational effects of nearby objects are effected. Earth will still orbit fine, so will Venus and any other planet in the solar system.

Now you might say "But where does all the mass of the original star go?", well first off, this question was what made Stephen Hawking famous. It was originally thought that the materials of the star are just gone, deleted. But if you do some quantum physics you will know that information cannot be destroyed, and therefore mass cannot just be deleted. What got Stephen Hawking famous was his Hawking radiation, which is literally Black Holes "radiating mass out of itself".

About the singularity, which is what the media says is "Mass squashed to an infinitesimal point". I think what you may be thinking is that black holes are massive objects, collapsed into an infinitesimal point called the singularity, therefore have infinite density.

We, again, have to be careful. The singularity isn't anything. It is not an object, not an event nor a location in spacetime. If you look at the diagrams you find on the internet, it might show the singularity as a point stretching the fabric of spacetime really far down, but that isn't it. Singularities are a hole in spacetime, and this hole makes the geodesics(you can think of geodesics like the "straight lines" of a curved geometry, basically the path an object would follow given by Newton's first law of motion in a curved space) so distorted that it is basically undefined.

Black holes are formed when a sufficiently massive object is collapsed into a volume smaller than the original object's Schwartzchild radius.(I realised this is rather jargon so you can search up about it) This usually means the "mass" of the black hole is equal to the original star that collapsed in the first place. However the horizon of the black hole first forms inside the star, and then expands. This means to external observers, the mass of the object never crosses the horizon. (Nothing ever crosses a black hole to an external observer as light never allows external oberservers to "see" and object crossing). So in this scenario, the mass of the black hole is redundant.

Another problem here is that the equation used to calculate a black hole (Einstein's Field Equations), also allows an empty universe with an eternal blackhole. If you're gonna talk about blackholes, you must include all of them, including this one. But in this case, what are you suppose to say about the mass of the black hole??? There is no mass, as defined by the equation, anywhere.

Glad to see my school works helping, at least in some way. But god dammit, I got carried away...
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Joined **September 2015**

I thought the answer was () (you divided the 0 in the middle and it splited into () )

How so? How would you even know what a 4D shape looks like? Let alone cut it. The motion of cutting implies 3D. How do you cut a 2D cake with a 2D knife without going to the 3rd Dimension?? (Slicing doesn't count)## Rifdi wrote:

Well assuming its a regular cylindrical cake3D is irrelevant when cutting the cake because of the subsection nature of the cut. If you have a 4D knife and cake on the other hand, then would play a role.

It should have 2pi*r^2*h of edible volume available.

Plus, what does a 4D cake even look like?? A 2D cake is pi*r^2, a 3D cake is pi*r^2*h, but the 2 shapes are different. The equivalent of a circle in 3D is a sphere, not some puny cylinder. Note: we can consider a cylinder as 2-2D objects: circles and a rectangle. So what is the combination for a 4D cake??

Cylinder + rectangular prism??(which is the equivalent of 2*circle*rectangle + rectangle*6 in 2D world). Cylinder + Sphere?

First off, it's 2pi## kai99 wrote:

my godWhy not?

why would you have 2pi of a cake tho

Joined **July 2014**

How so? How would you even know what a 4D shape looks like? Let alone cut it. The motion of cutting implies 3D. How do you cut a 2D cake with a 2D knife without going to the 3rd Dimension?? (Slicing doesn't count)First if you cut a 2D cake with a 2D knife, then your are effectively squashing it and not cutting it, because you know, like you said how would that go to the 3rd Dimension? It would make more sense to cut a 1D cake with a 2D knife. A 4D cake is impossible for a 3D being to comprehend, but it would would be a 4D cylinder. Here is a 4D cylinder being rotated in a crossection of 3D space:

Plus, what does a 4D cake even look like?? A 2D cake is pi*r^2, a 3D cake is pi*r^2*h, but the 2 shapes are different. The equivalent of a circle in 3D is a sphere, not some puny cylinder. Note: we can consider a cylinder as 2-2D objects: circles and a rectangle. So what is the combination for a 4D cake??

Cylinder + rectangular prism??(which is the equivalent of 2*circle*rectangle + rectangle*6 in 2D world). Cylinder + Sphere?

First off, it's 2pi radians of a cake. Things need units depending on what you're measuring. For example, when measuring your dick, you would say x dx long. Now if you don't know what radians are, you obviously haven't played enough MMORPG to know what raids are, which means you should go play more. Now since I'm a nice person, I'll explain what radians are. It's basically a unit that we use to see whether we hit the G spot or notPlease see this post and consider signing up to OT University's OT unit theory course.

Joined **July 2014**

This thread will be locked in 6 posts.This thread will need to be divided by 0 before that happens

Joined **February 2010**

Using real life examples is bad because you can do a lot of things in maths that don't work in real life.

Joined **July 2014**

Using real life examples is bad because you can do a lot of things in maths that don't work in real life.

Using real life examples is bad because you can do a lot of things in maths that don't work in real life.

BUT, If you were saying that certain things in math should be explained in a mathematical way then I agree with you.

Calculus uses infinitesimal, which is not realistic## silmarilen wrote:

Using real life examples is bad because you can do a lot of things in maths that don't work in real life.

BUT, If you were saying that certain things in math should be explained in a mathematical way then I agree with you.

Calculus uses infinitesimal, which is not realisticIt isn't realistic but there are real examples for it, black holes for one. All its mass is packed in a single infinitesimal point. Well at least in terms of size the concept of infinitesimal exists.

Did you just read an article about blackhole online?## Blitzfrog wrote:

Calculus uses infinitesimal, which is not realisticIt isn't realistic but there are real examples for it, black holes for one. All its mass is packed in a single infinitesimal point. Well at least in terms of size the concept of infinitesimal exists.

First off, Blackholes don't have mass. Not directly. They're not anything, how can they have mass? Black holes are not objects, they're what happens when you delete a region from the fabric of spacetime. We just talk about them like mass because they, similar to a massive object, exert gravitatational properties to other objects. For example, replace the sun with a black hole the size of the schwartzchild radius of the sun, and nothing about the gravitational effects of nearby objects are effected. Earth will still orbit fine, so will Venus and any other planet in the solar system.

Now you might say "But where does all the mass of the original star go?", well first off, this question was what made Stephen Hawking famous. It was originally thought that the materials of the star are just gone, deleted. But if you do some quantum physics you will know that information cannot be destroyed, and therefore mass cannot just be deleted. What got Stephen Hawking famous was his Hawking radiation, which is literally Black Holes "radiating mass out of itself".

About the singularity, which is what the media says is "Mass squashed to an infinitesimal point". I think what you may be thinking is that black holes are massive objects, collapsed into an infinitesimal point called the singularity, therefore have infinite density.

We, again, have to be careful. The singularity isn't anything. It is not an object, not an event nor a location in spacetime. If you look at the diagrams you find on the internet, it might show the singularity as a point stretching the fabric of spacetime really far down, but that isn't it. Singularities are a hole in spacetime, and this hole makes the geodesics(you can think of geodesics like the "straight lines" of a curved geometry, basically the path an object would follow given by Newton's first law of motion in a curved space) so distorted that it is basically undefined.

Black holes are formed when a sufficiently massive object is collapsed into a volume smaller than the original object's Schwartzchild radius.(I realised this is rather jargon so you can search up about it) This usually means the "mass" of the black hole is equal to the original star that collapsed in the first place. However the horizon of the black hole first forms inside the star, and then expands. This means to external observers, the mass of the object never crosses the horizon. (Nothing ever crosses a black hole to an external observer as light never allows external oberservers to "see" and object crossing). So in this scenario, the mass of the black hole is redundant.

Another problem here is that the equation used to calculate a black hole (Einstein's Field Equations), also allows an empty universe with an eternal blackhole. If you're gonna talk about blackholes, you must include all of them, including this one. But in this case, what are you suppose to say about the mass of the black hole??? There is no mass, as defined by the equation, anywhere.

Glad to see my school works helping, at least in some way. But god dammit, I got carried away...