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# Is it possible to get an abosolute perfect sphere? watch

1. Doesn't light (photons) travel through time or something like that?
2. (Original post by Cinematographic)
Doesn't light (photons) travel through time or something like that?
i <3 you
3. (Original post by Cinematographic)
Doesn't light (photons) travel through time or something like that?
OMG

SPACETIME there is no seperate space/time , it's the same thing.

light always travels at the speed of light

the problem with 'measuring' the speed of light is that time itself changes, so you can't say it travels 1 mile in 1 sec [I know it's much much faster] as it can travel 1 mile in 0.7s - it didn't go faster, just time changed.
4. (Original post by JordanCarroll)
i <3 you
Lol we're both way in over our heads :P

I watched (cringe) Horizon and there was some mad scientist discussing how relativity didn't seem to work at the quantum level. And he did this experiment where he fired light/photons and some weird sciency thing happened.

Do you want to share the dumb hat with me in the corner of the class?
OMG

SPACETIME there is no seperate space/time , it's the same thing.

light always travels at the speed of light

the problem with 'measuring' the speed of light is that time itself changes, so you can't say it travels 1 mile in 1 sec [I know it's much much faster] as it can travel 1 mile in 0.7s - it didn't go faster, just time changed.
It doesn't work when you look at quantum physics does it? Apparently that's the big problem in physics: combining special relativity with Quantum mechanics.
6. (Original post by Cinematographic)
Do you want to share the dumb hat with me in the corner of the class?
yeahhhh
I heard it from Neil Degrasse Tyson

Are you going to argue physics with him?
Nice argument from authority there
light always travels at the speed of light*
*in a vacuum
9. sub atomic particles are perfectly spherical on their own arent they?
Sub atomic particles are supposedly point-like, i.e. they are zero dimensional. This is not the same as perfectly spherical, as a sphere is a 3d geometrical object. The only perfect sphere is one that exists as an abstract mathematical object, because in reality trying to build such an object would always fail due to quantum mechanics (specifically the uncertainty principle).

The argument is as follows:

Uncertainty principle is
where x = position of particle, p = momentum and h = Planck's constant and is the uncertainty on these measurements.

To get a perfect sphere would require perfect placement of each atom constructing it, i.e. there could be no uncertainty on the positions of the atoms. This implies . The uncertainty principle then requires that the momentum of the atoms constructing it is completely undefined i.e.

Constructing a sphere at the atomic level would require atoms to be bound chemically together; in other words trapped in some kind of electrostatic potential well. A momentum state with infinite uncertainty can tunnel through any finite potential barrier, making it impossible to contain in practice.

This means that the act of placing a particle infinitly precisely (as is required to construct a perfect sphere) makes it physically impossible to contain this particle, meaning such a sphere would never be able to be constructed.
10. it only takes an infinite amount of time to reach the event horizon if you're trying to escape the gravitational pull. you could reach the singularity in finite time surely.
11. Also light doesn't travel through time - look at where For light, with v = c, this makes , meaning that one second in the rest frame of a photon takes an infinite amount of time to pass in any other frame. This means to the outside observer an infinite amount of time passes before any time passes for a photon, i.e. the photon is fixed in time.
12. (Original post by Eccentric)
Its not to do with pressure its to do with fundamental charges I thought o.O ?

Also as mentioned above hydrogen orbitals are not perfectly spherical, no shape is actually perfect to what we see it as (if that makes sense!).
ah yes i was sort of bending OP's question about pressure to find the closest fit...
but yes as someone shows I forgot they weren't spherical.

Weird because I thought it was just a s orbital which I thought was a sphere? thats what we get taught in chemistry anyway..

EDIT: in fact, I am right aren't I?

Hydrogen orbita is 1s....... which is a sphere?

Lol sorry you guys are probably all like degree level chemsitry so I'm sure your right but could you explain why?

Of course this is not a sphere of matter but a sphere of like force or electronegativeness or something like that haha, don't know what the proper term is.. but it is still a perfect sphere?
13. (Original post by latentcorpse)
it only takes an infinite amount of time to reach the event horizon if you're trying to escape the gravitational pull. you could reach the singularity in finite time surely.
was that an unrelated post lol?
14. (Original post by JayEm)
*in a vacuum
No.

Light ALWAYS travels at the speed of light, I just said it might be measured at being slower.

It may move through air a bit slower, but does that mean the light travelling between the hydrogen atoms isn't at the speed of light?

EDIT: light travels at 'light speed' confused with "what is the measured speed of light"

it's only when you give it a figure like ~186,000 miles/s then you need to include "in a vacuum" I didn't say light travels at 186,000m/s I just said it travels at light speed.
15. I thought it was just a s orbital which I thought was a sphere?
An orbital is actually a probability density function mapped in 3d, telling you the probability of finding an electron in a given volume of space - it can be perfectly spherical because it is a mathematical construct, not a physical object.
16. (Original post by JordanCarroll)
yeahhhh

Anyway I found reference to it. Basically time literally stops from the perspective of the photon. Yet from our perspective it is actually moving through time.

I thought that was a rather interesting mystery.
An orbital is actually a probability density function mapped in 3d, telling you the probability of finding an electron in a given volume of space - it can be perfectly spherical because it is a mathematical construct, not a physical object.
Yes I see this but although the orbital is not physical i.e. made out of matter, it is nevertheless REAL because it interacts with real objects: its not purely a theoretical construct.
18. Yes I see this but although the orbital is not physical i.e. made out of matter, it is nevertheless REAL because it interacts with real objects: its not purely a theoretical construct.
No it is not real, it is a purely theoretical concept - an orbital is merely a label to define a volume of space in which we expect to find an electron, given the potential well it is sitting in. In reality it is the electron that interacts with other objects, not the orbital.
No it is not real, it is a purely theoretical concept - an orbital is merely a label to define a volume of space in which we expect to find an electron, given the potential well it is sitting in. In reality it is the electron that interacts with other objects, not the orbital.
Hmm ok.. I see what you're saying but i'm still not completely convinced.
Since we can never know the position of the electron and its speed, things approaching the orbital will act in a way caused by the orbital of the electron. if the electron orbital was not spherical they would react in a different way. So they objects are interacting with the "sphere". I realise that the sphere is not physical but its shape still plays a role in how other things behave. If it was theoretical then it wouldn't make a difference.
20. The discussion of your opinions and views in the physics or general debate section is fine but basically everything adonis has said is false (and hence it has spurred many others to either believe him or come up with equally ridiculously claims) which is something I imagine the OP certainly did not want.

The topic is spheres; Mathematically they exist but of course we can never physically have a sphere.

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