Atheist Universe: Not Impossible

[Penumbra]

Kewl .

Not quite: they witness time going normally in the spaceship, and going slow outside.

A person on Earth sees their watch go normally, but a clock on the spaceship tick slowly. But confusingly, a person on the spaceship sees Earth's clocks running slowly! This leads to the wonderful world of simultaneity: events that are simultaneous in one inertial frame might occur at different times in another frame.

So someone driving alongside a train at a slightly lower speed than the train's speed (as measured by an observer on the train station) measure two events on the train to have occurred at the same point in time. But the observer on the platform sees the two events as occurring at different points in time.

Confused? It's all relative, m'dear.


You'd get the same answer: there is nothing special about the spaceship that would make its answer differ to the Earth's.


The question makes no sense, because you've assumed absolute motion. One of the fundamental points about relativity is that motion is relative (hence the name ). It makes no sense to say one particle is travelling faster than the other without defining some origin point (or a stationary observer, or whatever). Moreover, each particle sees itself as stationary, and the other particle moving away.

So particle A sees particle B whizzing away at some speed v, and thus sees B's clocks ticking slowly and sees B as being shorter than when it stationary (relative to A).
B also sees the same things about A.

A sees itself as being of normal length and its clocks ticking normally, but so does B. Length contraction and time dilation are phenonema observed by stationary observers watching moving objects. People on the moving object see themselves as being the stationary objects, and the previous observes as being the moving ones.

I hope I made sense! Relativity boggles everyone .

I applaud your patience with me... I think I have identified the area that I do not understand and so may be able to ask more specific questions.

I understand relative simultaneity to a degree. I learned it from an example about light from a flashlight striking a target on a moving train, much like your example.

Also, I misspoke/typed something in my last post. I do understand that for all parties involved, time seems to move at normal rate for them. People never see themselves as moving more slowly or quicker, just others.

What I don't understand, and what I never really grasped in class either, is that all parties involved see the other as moving more slowly. I would think that for the faster moving party, they would see others as moving more quickly. If a rocket ship takes off from earth, travels around Neptune, and comes back, wouldn't the people on the returned space ship argue with the people on earth about how much time has passed (assuming they are not knowledgeable about relativity, that is )? Maybe the people on earth witnessed the rocket leave 5 years ago, but the people on the rocket have only felt a year go by. That's what we learned in class: specifically, that a parent could travel in a space ship for a while, come back to earth, and find that their child is now older than them.

So what I'm confused about it is an apparent contradiction between things being absolute and relative. If all motion is relative, and each party sees their self as being the stationary one, then why does one age objectively faster than the other? Where am I messing up this time?

 

[Wiccan_Child]

I applaud your patience with me... I think I have identified the area that I do not understand and so may be able to ask more specific questions.

Ask away. This is a good refresher course for me too!

I understand relative simultaneity to a degree. I learned it from an example about light from a flashlight striking a target on a moving train, much like your example.

That's how I learned it too .

Also, I misspoke/typed something in my last post. I do understand that for all parties involved, time seems to move at normal rate for them. People never see themselves as moving more slowly or quicker, just others.

Yep.

What I don't understand, and what I never really grasped in class either, is that all parties involved see the other as moving more slowly. I would think that for the faster moving party, they would see others as moving more quickly. If a rocket ship takes off from earth, travels around Neptune, and comes back, wouldn't the people on the returned space ship argue with the people on earth about how much time has passed (assuming they are not knowledgeable about relativity, that is )? Maybe the people on earth witnessed the rocket leave 5 years ago, but the people on the rocket have only felt a year go by. That's what we learned in class: specifically, that a parent could travel in a space ship for a while, come back to earth, and find that their child is now older than them.

Yes, but that's to do with acceleration: motion is relative, but acceleration isn't. And acceleration is addressed by General Relativity: constantly accelerating is indistinguishable from sitting in a gravitational well, and time dilates asymmetrically when something is in a well.

So if the spaceship accelerates, flies round Neptune, and then decelerates to a halt back at Earth, time dilation does some funky things. Namely, someone on Earth watching a spaceship accelerate away sees its clock run slower than his clock, but the person in the spaceship doesn't see Earth's clocks running as slowly as Earth's sees his.
Or the other way around...
So while something's motion is relative, its acceleration is absolute.

So what I'm confused about it is an apparent contradiction between things being absolute and relative. If all motion is relative, and each party sees their self as being the stationary one, then why does one age objectively faster than the other? Where am I messing up this time?

Acceleration . Basically, you're assumption that the physics is symmetric is wrong: there's an objective difference because the spaceship accelerates. The spaceship is at rest in its inertial frame initially, but because it accelerates, it is now moving at some speed relative to the initial inertial frame. Objective difference is objective

Read up on this article, it's Wikipedia, so you know it's good.

 

[Penumbra]

Ask away. This is a good refresher course for me too!

That's how I learned it too .

Yep.

Yes, but that's to do with acceleration: motion is relative, but acceleration isn't. And acceleration is addressed by General Relativity: constantly accelerating is indistinguishable from sitting in a gravitational well, and time dilates asymmetrically when something is in a well.

So if the spaceship accelerates, flies round Neptune, and then decelerates to a halt back at Earth, time dilation does some funky things. Namely, someone on Earth watching a spaceship accelerate away sees its clock run slower than his clock, but the person in the spaceship doesn't see Earth's clocks running as slowly as Earth's sees his.
Or the other way around...
So while something's motion is relative, its acceleration is absolute.

Acceleration . Basically, you're assumption that the physics is symmetric is wrong: there's an objective difference because the spaceship accelerates. The spaceship is at rest in its inertial frame initially, but because it accelerates, it is now moving at some speed relative to the initial inertial frame. Objective difference is objective

Read up on this article, it's Wikipedia, so you know it's good.

I think I understand it a lot better now. Acceleration being absolute clears up my confusion on the space ship example and the apparent contradiction between that which is relative and that which is absolute.

Now, when you say "but the person in the spaceship doesn't see Earth's clocks running as slowly as Earth's sees his.", does that imply that someone on the spaceship could see Earth's clocks running more quickly than their own? The way you worded it confused me, though I would think that if the space ship returns after so much accelerating, then at some point during the trip it must notice Earth's clocks moving very quickly.

Oddly, I learned about acceleration being indistinguishable from a gravity well by a train example also. Physicists must really like trains. In our example, we saw that if you were in a closed train with no windows, there would be no way to distinguish, from inside the train, whether the train was accelerating or if it was under the influence of gravity of the same magnitude. We only touched on general relativity, though. I'm not too good with it quantitatively.

Going back to my original question about the age of the universe being relative or absolute....

If two particles with mass have undergone different rates of acceleration for various reasons since their initial expansion at time = 0 of the universe, is it possible that they would disagree as to how long they've been in existence? They would both experience time flowing normally for their own selves, but if one has had more accelerating factors than the other throughout its lifetime since the initial expansion, wouldn't the absolute concept of acceleration state that one of them has "aged" more quickly? Or no?

 

[Wiccan_Child]

I think I understand it a lot better now. Acceleration being absolute clears up my confusion on the space ship example and the apparent contradiction between that which is relative and that which is absolute.

Now, when you say "but the person in the spaceship doesn't see Earth's clocks running as slowly as Earth's sees his.", does that imply that someone on the spaceship could see Earth's clocks running more quickly than their own? The way you worded it confused me, though I would think that if the space ship returns after so much accelerating, then at some point during the trip it must notice Earth's clocks moving very quickly.

A clock in the deep end of a gravity well will tick slower than a clock in the shallow end. So a clock in interstellar space ticks faster than a clock on Earth, since the Earth creates a well around it.

So yes, the spaceship would see Earth's clocks running faster than its own (though it would see its clocks running at 'normal' speed).

Take black holes, the quintessential gravity well: things near a black hole appear to be running slower than things further away, and someone near a black hole sees the rest of the universe running fast.

Going back to my original question about the age of the universe being relative or absolute....

If two particles with mass have undergone different rates of acceleration for various reasons since their initial expansion at time = 0 of the universe, is it possible that they would disagree as to how long they've been in existence? They would both experience time flowing normally for their own selves, but if one has had more accelerating factors than the other throughout its lifetime since the initial expansion, wouldn't the absolute concept of acceleration state that one of them has "aged" more quickly? Or no?

Yes, they would disagree. Just as our twins would go from being the same age, to being different ages, so too would our particle disagree on just how much time has elapsed.

 

[Penumbra]

Yes, they would disagree. Just as our twins would go from being the same age, to being different ages, so too would our particle disagree on just how much time has elapsed.

So if the particles disagree as to how old they are and therefore how old the universe is, then what does that imply?

Going back full circle to my first question, how can astronomers say that the universe really is 13.7 billion years old if various particles in the universe may disagree with that number? Why is that reference frame more valid than any other?

Is the reference frame they measure from supposed to be the frame that does not accelerate, and that's why it is most valid? (Seeing as I now realize that acceleration is absolute...) But if the expansion of the universe itself is accelerating, how can this frame be said to not be accelerating? Or is that not the reason they pick that specific frame?

 

[Penumbra]

Oh and as for massless particles traveling at light speed....

If they do not experience time like we do, how can they have a finite velocity of about 3*10^8 meters per second? How can these particles change their position in spacetime if they do not experience time like particles with mass do?

You don't have to answer all these if you don't feel like it.

 

[andross77]

... And to me, it seems, very probable.

BEFORE YOU READ:

I realize that this theory / hypothesis / concept / whatever is not going to be the end-all creationism vs. atheism debate. This is just an idea I found interesting and wanted to see what everybody here thought about it.

ON TO THE SUBJECT:

I just had this sort of thought bouncing around in my head, and I think I had an epiphany. That or my brain exploded. Okay, consider this:

Before the universe existed, there were no laws. Of anything. No physics, no logic, no nothing.

If such a blank nothingness existed without laws, literally anything could happen.

In the infinite amount of time that the nothingness existed, it is infinitely probable for anything and everything to be created. Since there is an infinite amount of time and no binding guidelines, literally every possibility must be fulfilled.

This includes the spontaneous creation of our universe.

----------------------


Put that in your pipe and smoke it, creationists.

your epiphany is not well supported. your logic is exactly the opposite of...well, logic.

If there is absolutely nothing....there is absolutely NO CHANCE of ANYTHING. You can't have ABSOLUTELY NOTHING AND the possibility of ABSOLUTELY EVERYTHING. it's a complete contradiction. Try again.

 

[Penumbra]

your epiphany is not well supported. your logic is exactly the opposite of...well, logic.

If there is absolutely nothing....there is absolutely NO CHANCE of ANYTHING. You can't have ABSOLUTELY NOTHING AND the possibility of ABSOLUTELY EVERYTHING. it's a complete contradiction. Try again.

I don't particularly agree with any theory about anything prior to the Big Bang, seeing as it is all guesswork, but I see a dilemma in your post.

PhilosophicalBluster implied that in a world with nothing, not even logic, anything can happen.

Your argument against him was that with absolutely nothing, there is no chance of anything. This statement of yours is founded on logic, though, which under his assumption, does not exist at that time.

Without logic, everything is silly, and I don't think anything can be stated as fact...

 

[Wiccan_Child]

your epiphany is not well supported. your logic is exactly the opposite of...well, logic.

If there is absolutely nothing....there is absolutely NO CHANCE of ANYTHING. You can't have ABSOLUTELY NOTHING AND the possibility of ABSOLUTELY EVERYTHING. it's a complete contradiction. Try again.

You lambaste him for bad logic, but then your rebuttal is little more than "Assume there is no chance something can come from nothing. Therefore, something can't come from nothing". Your logic is valid, but unsound.

 

[Wiccan_Child]

So if the particles disagree as to how old they are and therefore how old the universe is, then what does that imply?

It implies that the particles consider the universe to be different ages. However, since those particles don't exist (as far as I'm aware), it's just a curious consequence of general relativity.

Going back full circle to my first question, how can astronomers say that the universe really is 13.7 billion years old if various particles in the universe may disagree with that number? Why is that reference frame more valid than any other?

It isn't. The age of the universe is calculated objectively, not relatively. It doesn't which frame you calculate from, the age of the universe is the same.

When you accelerate, you go from being stationary in your initial inertial frame, to moving at some speed relative to it (much how a spaceship initially at rest on Earth accelerates, and thus is now moving at a speed relative to the Earth).

However, the inertial frame itself doesn't change: the age of the universe as measured in that frame is the same as it is in all frames.

Is the reference frame they measure from supposed to be the frame that does not accelerate, and that's why it is most valid? (Seeing as I now realize that acceleration is absolute...)

Aye.

But if the expansion of the universe itself is accelerating, how can this frame be said to not be accelerating? Or is that not the reason they pick that specific frame?

Both: how the universe

Oh and as for massless particles traveling at light speed....

If they do not experience time like we do, how can they have a finite velocity of about 3*10^8 meters per second? How can these particles change their position in spacetime if they do not experience time like particles with mass do?

They have a finite velocity because 3*10[up]8[/sup] is the maximum velocity at which particles can move. It's also how we see them move. Photons, it they have a perception of time similar to us, don't see them moving at all. Rather, they see all events happening at once.

We don't, but they do.

You don't have to answer all these if you don't feel like it.

Haha I don't mind. I'm finally putting my degree to the test!

 

[Penumbra]

It implies that the particles consider the universe to be different ages. However, since those particles don't exist (as far as I'm aware), it's just a curious consequence of general relativity.

Why don't those particles exist? Doesn't every massive particle fit the description?

Is the reason those particles don't exist due to the fact that at the beginning of the big bang, all initial components were particles without mass?

Does a massive particle turning into pure energy, or energy turning back into that mass, affect relativity at all? Say, for example, our spaceship around neptune example: if the ship at one point on its journey was completely turned into energy (i.e. e=mc^2), and those energy particles reassembled into the ship (however unlikely- just a thought experiment.....), when that ship gets back to earth after so much acceleration and deacceleration, wouldn't less time have passed for that ship? It was made of atoms, converted into photons, and then reassembled into atoms. Or would the interruption of being turned into pure energy have distorted and undone everything?

During the course of the universe, matter gets created from energy, and much of that matter gets converted back to energy, and so forth. But all of the particles involved are discrete units: electrons, neutrinos, photons, and so forth. So the spaceship being turned into energy is silly, but it's just me trying to use it as an example of what occurs in the universe all the time.

So I guess my question is, how can those particles not exist, since particles can never really be destroyed, just converted?

It isn't. The age of the universe is calculated objectively, not relatively. It doesn't which frame you calculate from, the age of the universe is the same.

When you accelerate, you go from being stationary in your initial inertial frame, to moving at some speed relative to it (much how a spaceship initially at rest on Earth accelerates, and thus is now moving at a speed relative to the Earth).

However, the inertial frame itself doesn't change: the age of the universe as measured in that frame is the same as it is in all frames.

I guess no matter how many times you explain it, this part will always elude me.

I don't understand how, no matter what reference frame it is calculated from, the age of the universe is the same, whereas in the rocket ship example, different reference frames will calculate different ages for the ship. I'm not grasping what the difference is here. I think I'll just give this part up- I think you're probably explaining it ok, but I'm just not understanding....

Aye.

Both: how the universe

They have a finite velocity because 3*10[up]8[/sup] is the maximum velocity at which particles can move. It's also how we see them move. Photons, it they have a perception of time similar to us, don't see them moving at all. Rather, they see all events happening at once.

We don't, but they do.

Ok, I see.

Is the speed of light an arbitrary aspect of the universe, or is it that way because it cannot be any other speed? I know that the speed of light is derived from an equation involving the magnetic permeability and electric permittivy of the universe, u0 and e0, and these constants are affected by the medium, but are these constants arbitrary, or do scientists know why these numbers are equal to what they are?

Haha I don't mind. I'm finally putting my degree to the test!

Well, thanks for putting up with me.

Do you already have a degree at 20 years of age?

 

[Penumbra]

This is going to give me a headache.

 

[Wiccan_Child]

Why don't those particles exist? Doesn't every massive particle fit the description?

Is the reason those particles don't exist due to the fact that at the beginning of the big bang, all initial components were particles without mass?

Does a massive particle turning into pure energy, or energy turning back into that mass, affect relativity at all? Say, for example, our spaceship around neptune example: if the ship at one point on its journey was completely turned into energy (i.e. e=mc^2), and those energy particles reassembled into the ship (however unlikely- just a thought experiment.....), when that ship gets back to earth after so much acceleration and deacceleration, wouldn't less time have passed for that ship? It was made of atoms, converted into photons, and then reassembled into atoms. Or would the interruption of being turned into pure energy have distorted and undone everything?

During the course of the universe, matter gets created from energy, and much of that matter gets converted back to energy, and so forth. But all of the particles involved are discrete units: electrons, neutrinos, photons, and so forth. So the spaceship being turned into energy is silly, but it's just me trying to use it as an example of what occurs in the universe all the time.

So I guess my question is, how can those particles not exist, since particles can never really be destroyed, just converted?

Well, the particles are destroyed, but conservation laws requires that new particles take their place (e.g., an electron and a positron will annihilate each other, but from this pops a brand new pair of μ[sup]+[/sup] ν[sub]μ[/sub] particles).

But I said our hypothetical particles don't exist because no particle has been accelerating uniformly for the past 13.5 billion years: they will inevitably experience some force or other and their acceleration will change. There are also energy constraints: it takes energy to accelerate something, and the universe has but a finite supply (as far as we can tell ).

I guess no matter how many times you explain it, this part will always elude me.

I don't understand how, no matter what reference frame it is calculated from, the age of the universe is the same, whereas in the rocket ship example, different reference frames will calculate different ages for the ship. I'm not grasping what the difference is here. I think I'll just give this part up- I think you're probably explaining it ok, but I'm just not understanding....

It's because the age of the ship changes. The accelerating thing is what undergoes dilation; everything else behaves normally, sipping their cocktails and gossiping about the ship's unseemly behaviour.

The universe isn't accelerating, so it doesn't experience time dilation.

Is the speed of light an arbitrary aspect of the universe, or is it that way because it cannot be any other speed? I know that the speed of light is derived from an equation involving the magnetic permeability and electric permittivy of the universe, u0 and e0, and these constants are affected by the medium, but are these constants arbitrary, or do scientists know why these numbers are equal to what they are?

Damn, I was going to mention u[sub]0[/sub] and ε[sub]0[/sub], but you beat me to it . In essence, the nature of spacetime determines these vacuum permittivity and permeability, so yes: the speed of light is an inherent property of the universe.

However, these properties are in turn determined by the nature and interactions of the electromagnetic force. Light is, after all, the mediator of the EM force.

Do you already have a degree at 20 years of age?

Almost; I graduate this July

 

[Penumbra]

Well, the particles are destroyed, but conservation laws requires that new particles take their place (e.g., an electron and a positron will annihilate each other, but from this pops a brand new pair of μ[sup]+[/sup] ν[sub]μ[/sub] particles).

But I said our hypothetical particles don't exist because no particle has been accelerating uniformly for the past 13.5 billion years: they will inevitably experience some force or other and their acceleration will change. There are also energy constraints: it takes energy to accelerate something, and the universe has but a finite supply (as far as we can tell ).

As far as I know, the particles don't need to accelerate uniformly for it to experience time dilation relative to another particle. If the space ship traveling to Neptune and back takes a couple pit stops for gas, flies in a few extra circles, and then comes back to Earth, time dilation still occurred, correct?

So for the particles traveling around since the Big Bang, one would assume that due to reasons of probability, some particles have undergone a larger average amount of acceleration and de-acceleration than other particles, due to various matter and energy interactions that they have randomly encountered. We don't need infinite energy to assume that some particles have accelerated more than others, do we?

It's because the age of the ship changes. The accelerating thing is what undergoes dilation; everything else behaves normally, sipping their cocktails and gossiping about the ship's unseemly behaviour.

The universe isn't accelerating, so it doesn't experience time dilation.

If particles in the universe accelerate, and the expansion of spacetime itself is accelerating, is the universe still not considered accelerating? Isn't the universe just the sum of its parts?

Is the universe considered not to be accelerating because it is accelerating in all directions simultaneously, and hence more like a growing stationary object and therefore not really accelerating compared to anything else?

Damn, I was going to mention u[sub]0[/sub] and ε[sub]0[/sub], but you beat me to it . In essence, the nature of spacetime determines these vacuum permittivity and permeability, so yes: the speed of light is an inherent property of the universe.

However, these properties are in turn determined by the nature and interactions of the electromagnetic force. Light is, after all, the mediator of the EM force.

I see.

Almost; I graduate this July

Nice!

Did you enter your university at a young age, or take an accelerated course load, or do universities in the United Kingdom grant degrees to younger people on average than in the United States??

 

[Wiccan_Child]

As far as I know, the particles don't need to accelerate uniformly for it to experience time dilation relative to another particle. If the space ship traveling to Neptune and back takes a couple pit stops for gas, flies in a few extra circles, and then comes back to Earth, time dilation still occurred, correct?

Correct.

So for the particles traveling around since the Big Bang, one would assume that due to reasons of probability, some particles have undergone a larger average amount of acceleration and de-acceleration than other particles, due to various matter and energy interactions that they have randomly encountered. We don't need infinite energy to assume that some particles have accelerated more than others, do we?

No. And you're right: if we attached timers onto each particle and synced them up at the moment of the Big Bang, today's particles (assuming none have been annihilated) would read slightly different values.

But the point is, given the utterly unfathomable number of particles in the universe, this statistical fluctuation gets very very quickly drowned out by the averaging process. That is, if one or two particles were very lucky and accelerated for far longer than any other particle, their could say that they're only a few seconds old for all the good it would do.

The average value on these hypothetical timers is the same: 13.5 billion years. While individual timers may vary somewhat by a few nanoseconds, this is completely negligible: it's a tiny percentage change from the 'true' figure, and the averaging processes negates it even more.

God I love statistics .

If particles in the universe accelerate, and the expansion of spacetime itself is accelerating, is the universe still not considered accelerating? Isn't the universe just the sum of its parts?

Depends on what you consider its 'parts'. The expansion of spacetime is accelerating, but you mustn't confuse motion-acceleration with other forms that have nothing to do with motion or relativity (colloquially, something is 'accelerating' if its rate is changing; only a velocity change is the acceleration we want, and is the only thing that causes gravitational time dilation).

Nothing like a little semantic word-play to confuse you further.

Is the universe considered not to be accelerating because it is accelerating in all directions simultaneously, and hence more like a growing stationary object and therefore not really accelerating compared to anything else?

It's a great conceptual tool to imagine it as an expanding, but stationary, bubble. The rate at which it gets bigger is itself increasing, or in other words 'accelerating'. But the bubble is, ostensibly, stationary.

Of course, this analogy assumes the existence of external space outside the bubble into which it's expanding. This isn't the case with the expansion of spacetime, but it's a good enough metaphor.

Did you enter your university at a young age, or take an accelerated course load, or do universities in the United Kingdom grant degrees to younger people on average than in the United States??

I remember reading somewhere that US university students start quite a bit later than UK students (advanced students notwithstanding). I don't know for sure, though.

 

[Penumbra]

Correct.

No. And you're right: if we attached timers onto each particle and synced them up at the moment of the Big Bang, today's particles (assuming none have been annihilated) would read slightly different values.

But the point is, given the utterly unfathomable number of particles in the universe, this statistical fluctuation gets very very quickly drowned out by the averaging process. That is, if one or two particles were very lucky and accelerated for far longer than any other particle, their could say that they're only a few seconds old for all the good it would do.

The average value on these hypothetical timers is the same: 13.5 billion years. While individual timers may vary somewhat by a few nanoseconds, this is completely negligible: it's a tiny percentage change from the 'true' figure, and the averaging processes negates it even more.

God I love statistics .

So the reference frame that astronomers use to measure the age of the universe is synonymous with the average of the bell curve of all particle reference frames?

Depends on what you consider its 'parts'. The expansion of spacetime is accelerating, but you mustn't confuse motion-acceleration with other forms that have nothing to do with motion or relativity (colloquially, something is 'accelerating' if its rate is changing; only a velocity change is the acceleration we want, and is the only thing that causes gravitational time dilation).

Nothing like a little semantic word-play to confuse you further.


It's a great conceptual tool to imagine it as an expanding, but stationary, bubble. The rate at which it gets bigger is itself increasing, or in other words 'accelerating'. But the bubble is, ostensibly, stationary.

Of course, this analogy assumes the existence of external space outside the bubble into which it's expanding. This isn't the case with the expansion of spacetime, but it's a good enough metaphor.

Ok, I understand the concept even though the visual imagery doesn't quite match up with what's really occurring.

I remember reading somewhere that US university students start quite a bit later than UK students (advanced students notwithstanding). I don't know for sure, though.

We generally start college at 18 and graduate at around 22, with variations of course.

I'm out of questions now; you've pretty much answered everything.

 

[Wiccan_Child]

So the reference frame that astronomers use to measure the age of the universe is synonymous with the average of the bell curve of all particle reference frames?

Pretty much, though it's not so much a curve as it is a sharp spike.

Ok, I understand the concept even though the visual imagery doesn't quite match up with what's really occurring.

Relativity and quantum mechanics has the habit of not conforming to our fleshy brains .

We generally start college at 18 and graduate at around 22, with variations of course.

Ah, I started university at 17. Is it common to call university 'college'? Over here, 'college' is the two years before uni.

I'm out of questions now; you've pretty much answered everything.

Cool! If you ever have any more, you know where to find me .

 

[Penumbra]

Ah, I started university at 17. Is it common to call university 'college'? Over here, 'college' is the two years before uni.

"College" here can have a lot of definitions. We also have two year colleges, though they are generally called community colleges to be more specific because they are cheaper to attend if you live near them: hence they serve the community. There are many four year colleges; possibly as many as there are universities.

When someone is going to get a four year degree, she will generally say that she is "going to college" instead of "going to university", even if the institution she is attending is called "the such and such university". Or when people recall their college days, they will generally say "back when I was in college..." even if the institution they went to is called a university.

The line between college and university is blurred in America, considering that both can be four year degree, or advanced degree granting institutions. Usually, for a school here to be called a university, it must be rather large. Often public institutions paid partially by the state, are called universities and private institutions are either called colleges or universities, generally depending on how large they are or what they want to call themselves.

Sometimes universities break their departments into units called "colleges". For example, I go to a university and am in the college of engineering at that university.

When I talk to people from other countries, I try to call it a university but sometimes I forget to.

/unnecessary derail, but now you know

 

[Wiccan_Child]

"College" here can have a lot of definitions. We also have two year colleges, though they are generally called community colleges to be more specific because they are cheaper to attend if you live near them: hence they serve the community. There are many four year colleges; possibly as many as there are universities.

When someone is going to get a four year degree, she will generally say that she is "going to college" instead of "going to university", even if the institution she is attending is called "the such and such university". Or when people recall their college days, they will generally say "back when I was in college..." even if the institution they went to is called a university.

The line between college and university is blurred in America, considering that both can be four year degree, or advanced degree granting institutions. Usually, for a school here to be called a university, it must be rather large. Often public institutions paid partially by the state, are called universities and private institutions are either called colleges or universities, generally depending on how large they are or what they want to call themselves.

Sometimes universities break their departments into units called "colleges". For example, I go to a university and am in the college of engineering at that university.

When I talk to people from other countries, I try to call it a university but sometimes I forget to.

/unnecessary derail, but now you know

You know when you said you were confused about Relativity? Yeah, I think my brain just popped when I read your post .
Not that it was a bad post, but my noggin' can't cope with this paradigm shift .

 

[Penumbra]