Warping Space, Time, and Distance, page 4

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reply posted on 7-5-2012 @ 06:32 PM by CLPrime

Originally posted by ImaFungi

Is there an up and down to this region?

Nope, there's not. There is no frame of reference in empty space. Even in non-empty space, this is a relative issue - what's 'up' for Carmen in Cordova is 'down' for Waldo in Wellington.

what if we were launching a spaceship that could travel lightyears in seconds from the northpole, and kept going straight, would we eventually be able to view a birds eye view of the universe?

There's no such thing as a bird's-eye view of the universe. That implies you could leave the universe...which you can't. If you were trapped inside a balloon, could you get a bird's-eye view of it?
Plus, what would be a bird's-eye view for you, with the Earth's north pole pointing a certain direction, won't be a bird's-eye view for Uranians, with the north pole of Uranus pointing in a completely different direction. And that's just two planets in the same solar system. Planets in other solar systems and other galaxies only compound the problem.

what if we were in a space ship and traveled outside of our galaxy and then idled for "a very long time"
would we be eventually moved by surrounding forces, or would we eventually get run into by another galaxy?/ ( is it possible for anything to be completely still for a long period of time?)

Idle relative to what? Our galaxy? In that case, the gravitational pull of the galaxy would eventually (probably over millions, maybe even billions, of years, depending on our distance) pull us back in.
It's also possible that another galaxy would run into us...and, in that case, it would probably pass through the Milky Way.
If we're not idling with respect to the Milky Way, then you have to pick something else to be idling relative to. You can't idle relative to empty space, there's no point of reference.
It's possible to be completely still, if you can provide enough artificial thrust to counteract whatever gravitational forces are acting on the ship, but you have to pick something to be completely still in relation to.

ETA: by the way, with this discussion on the issue of there being no frame of reference in an empty space (that is, a vacuum), I'm hoping we'll get to one topic in particular. I just want to wait until I know you've all got this "no frame of reference in a vacuum" thing down first. Then, I'll pile on the reallly cool stuff.

edit on 7-5-2012 by CLPrime because: (no reason given)

reply posted on 7-5-2012 @ 06:52 PM by artistpoet

So energy it seems has a spiraling motion like in a Galaxy or water running down a plughole.
Or indeed a Tornado yet the center is still or appears that way though it is in fact moving it is calm and still in the eye so to speak. Is this not the same for the center of a galaxy or spinning orb of energy such as a star.

EDIT There is a point or singularity at the centre which is still

edit on 7-5-2012 by artistpoet because: (no reason given)

reply posted on 7-5-2012 @ 06:59 PM by CLPrime

reply to post by artistpoet

Energy doesn't typically have a spiralling effect (charged particles spiral through an electric field, but that's about it), it just happens that most large-scale structures rotate.
Water spirals down a drain because of the shape of the surface around the drain, the way the water reacher the drain, how level the drain is, and so on. Tornados spin because of the conditions that create them: wind shear. Hurricanes rotate because of the Coriolis effect, which itself is due to the rotation of the Earth. And, once you get to planets and other celestial objects, rotation is the norm due to intrinsic angular momentum from when these objects formed.

That "singularity" at the center of a galaxy is a black hole, and it rotates along with everything else around it.

edit on 7-5-2012 by CLPrime because: (no reason given)

reply posted on 7-5-2012 @ 07:06 PM by ImaFungi

reply to post by CLPrime

"by the way, with this discussion on the issue of there being no frame of reference in an empty space (that is, a vacuum), I'm hoping we'll get to one topic in particular. I just want to wait until I know you've all got this "no frame of reference in a vacuum" thing down first. Then, I'll pile on the reallly cool stuff."

I give up, can you pile it on

reply posted on 7-5-2012 @ 07:09 PM by artistpoet

reply to post by CLPrime

The reason I said what I did is an idea I have that black holes as such are inter dimensional gateways or portals for highly refined matter or energy or something exotic off the radar of our knowledge - more a philosophy
But please go onto the good stuff you spoke of it sounds intriguing

reply posted on 7-5-2012 @ 07:17 PM by CLPrime

reply to post by ImaFungi

Alrighty...first, a question.
Let's say you have a car with rocket engines. You leave the Earth in the direction opposite the Sun at a speed of 10 km/s - so, you're travelling at 10 km/s relative to the Sun. You travel out past Mars. If a Martian measured your speed, would they say you're moving at 10 km/s, or some other speed?

reply posted on 7-5-2012 @ 07:22 PM by artistpoet

Originally posted by CLPrime
reply to post by ImaFungi

Alrighty...first, a question.
Let's say you have a car with rocket engines. You leave the Earth in the direction opposite the Sun at a speed of 10 km/s - so, you're travelling at 10 km/s relative to the Sun. You travel out past Mars. If a Martian measured your speed, would they say you're moving at 10 km/s, or some other speed?

No they would measure it relative to the speed of Mars rotation

reply posted on 7-5-2012 @ 07:22 PM by ImaFungi

reply to post by CLPrime

they would measure it 10 km/s plus the speed of mars? but it would really be traveling the speed recorded by the car relative to its measurement of distance/ time.

reply posted on 7-5-2012 @ 07:32 PM by CLPrime

reply to post by artistpoet

Mars' rotation as well as relative to Mars' orbital speed. They might find your speed to be, say, 15 km/s. They could even say you're moving away from them if Mars is moving faster than you in any particular direction.

reply to post by ImaFungi

Okay...so the car says it's travelled x distance in t time. That gives v velocity.
But what about the Martians on Mars? They could legitimately measured the distance you travelled relative to Mars. The only "issue" with that is that Mars is moving. That's going to change their distance measurement, which is, again, going to alter their velocity measurement.

No matter what, it all depends on who you ask, and on what you're going to call the "rest frame" - the frame of reference that's at rest. You can just as easily call that reference frame the car as you could the Sun or the Earth or Mars. In fact, if you make the car your rest frame, you won't be travelling anywhere at all...everything else will be travelling around it, but the car won't be moving any distance.

This leads to a disparity:
Observers on each of the 8 planets would potentially say you have 8 different speeds. And your speed relative to the Sun is another speed. And the car's speed relative to itself is another. And relative to each of the asteroids in the Asteroid Belt is another few thousand different speeds. And relative to other stars is another whole bunch of different speeds.

That gives a lot of different, but equally valid, speeds for your one rocket-powered car.
All good so far?

edit on 7-5-2012 by CLPrime because: (no reason given)

reply posted on 7-5-2012 @ 07:37 PM by dragonridr

Originally posted by jiggerj

Originally posted by ImaFungi
reply to post by jiggerj

the sun is huge compared to planets.. its diameter is almost a million miles.... if it is effecting the planets enough for them to orbit the sun via gravity, why is it hard to imagine the space around the planet and in-between is effected by the sun...

If we're talking gravity, we little beings can jump off the ground. Of course we fall back down, but we aren't a planet billions of miles away from the sun. I'm pretty sure the Voyager image taken of the sun from 3 billion miles away made the sun look as small as a golf ball from that distance. Add another billion miles and the sun would look the size of a gumball. And it holds Neptune in place?

Is it possible that each planet exerts some kind of force on every other planet, thereby keeping them all corralled around the sun? <--- I could buy that more than just the sun doing it.

No the sun creates a gravity well around it this causes space time to distort.The space-time surrounding a gravitating body is curved and represents a spherical field.The closer you get to a massive body the more the distortion.Objects remain in orbit around a massive body due to gravity and their angular momentum. Objects in orbit are moving sideways, approximately at right angles (90 degrees) to the force of gravity.This is why planets take on an elliptical orbit in fact.At one point were pulled closer gaining speed then we slingshot out again. So in effect,50 percent of the time planets are "falling" around the massive body.

Now not to get to deep in math planets also create a distortion of space time. There is a direct proportion between mass and gravitational force, If you double the mass of one body, the gravitational force between them is also doubled. The gravitational force is inversely proportional to the square of the distance: If you double the distance between the two bodies, the force of gravity is reduced to one-fourth its original value. So the planets are also pulling on the sun as well,In fact this is how we can detect planets on distant stars it creates a wobble in the suns path that we can see.

reply posted on 7-5-2012 @ 07:44 PM by ImaFungi

reply to post by CLPrime

well wouldnt the correct measurement be from the car, because your measuring via the atomic second so time is a controled ruler of measurement, you just need reference for the distance you traveled in a certain amount of time?

i remember seeing something with the speed you traveling has an effect on time, it was shown with the time it takes a photon to bounce between to mirrors,, the faster you are traveling in a direction the longer it takes for the photon to hit the mirror because it has to compensate for the movement over distance... is this the same with the atomic second?

reply posted on 7-5-2012 @ 08:00 PM by CLPrime

Originally posted by ImaFungi

i remember seeing something with the speed you traveling has an effect on time, it was shown with the time it takes a photon to bounce between to mirrors,, the faster you are traveling in a direction the longer it takes for the photon to hit the mirror because it has to compensate for the movement over distance... is this the same with the atomic second?

That's not quite how the photon-mirror thing works, but it's close enough for now. And, it depends what you mean by "atomic second."

well wouldnt the correct measurement be from the car, because your measuring via the atomic second so time is a controled ruler of measurement, you just need reference for the distance you traveled in a certain amount of time?

No. Even the car can have many different results. Is it measuring its travelled distance with respect to the Earth? Mars? the Sun? All of these things are moving independent of the car. It has to measure its distance relative to the exact point in space from where it left...but where is that point? You can't find it relative to the Sun because the Sun is moving through space. The whole Solar System is moving through space. The galaxy is moving through space. The local group of galaxies is moving through space. No matter how big you go, everything is moving through space. How can you pin down that exact point of departure in order to calculate the distance travelled?

As I said, the car's motion can even be measured relative to the car, itself...in which case the car is not moving at all.

Or, look at it this way. Remove all matter from the universe. It's just you and you're car...no frame of reference at all. Now tell me: how fast are you moving?

reply posted on 7-5-2012 @ 08:09 PM by artistpoet

You are not moving in relation to anything?

reply posted on 7-5-2012 @ 08:14 PM by CLPrime

reply to post by artistpoet

I just asked my mother this same question. It's like asking a computer to find the last digit of pi.

The answer is (and you've got it), with no frame of reference, there is no possible definition of motion.

But that leads to a new problem: in a universe full of matter, there are an infinite number of equally valid ways to measure the motion of a single object (in this case, you and your fancy rocket-car).

So, what if you're a photon travelling through space?

reply posted on 7-5-2012 @ 08:20 PM by artistpoet

reply to post by CLPrime

If I was a photon traveling through space my speed would be relative to other photons yet photons could be traveling in all directions so the same rule applys as the car traveling through space away from the Sun - If I have understood you correctly that is

reply posted on 7-5-2012 @ 08:24 PM by CLPrime

reply to post by artistpoet

In fact, not just relative to other photons, but everything. One photon can have an infinite number of speeds according to different frames of reference.
And, if we return to the empty universe, you can't say the photon has any speed at all.

To drive this point home, if a photon is travelling through a vacuum, it has no single preferred reference frame to measure its motion. A photon always has an infinite number of possible reference frames from which to measure its speed.

Are you at all familiar with Maxwell's equations?

edit on 7-5-2012 by CLPrime because: (no reason given)

reply posted on 7-5-2012 @ 08:27 PM by artistpoet

Originally posted by CLPrime
reply to post by artistpoet

Are you at all familiar with Maxwell's equations?
edit on 7-5-2012 by CLPrime because: (no reason given)

No not familiar with Maxwell's equations?

reply posted on 7-5-2012 @ 08:35 PM by CLPrime

reply to post by artistpoet

Maxwell's equations (actually several equations described by people other than Maxwell) describe the nature of light and the formation of electric, magnetic, and electromagnetic fields.
What Maxwell found was that a changing/moving magnetic field generates an electric field. He also found that a changing/moving electric field generates a magnetic field. If you start out with, say, a magnetic field that's moving just right, it will create an electric field that's moving just right to create another magnetic field moving like the initial field was. And, of course, that new magnetic field will create a new electric field, and so on. This continual process of the electric field creating the magnetic field, the magnetic field recreating the electric field, the new electric field recreating the magnetic field, and so on, is what sustains the electromagnetic wave.
Combining two of Maxwell's equations shows what contraints have to be satisfied in order for the this to occur: the fields have to be travelling at exactly 299,792,458 m/s.

So, based on everything we've seen so far, that begs the question: that's 299,792,458 m/s according to which reference frame?

reply posted on 7-5-2012 @ 08:43 PM by artistpoet

reply to post by CLPrime

The elecro magnetic field would be moving at its reference or relation to other elecro magnetic fields?
Are these fields attached to stars and planets?

reply posted on 7-5-2012 @ 08:49 PM by CLPrime

reply to post by artistpoet

No, they're not attached.
And why just other EM fields? Why not all other particles or objects? That's what the entire follow-up was for...to establish that there are an infinite number of ways to measure motion in a matter-filled universe, the same as there is no way to measure motion in an empty universe.

So, a photon is travelling through empty space. It must be travelling at 299,792,458 m/s. With respect to what?

In an empty universe, you can't say it's travelling at all, let alone at 299,792,458 m/s
In a matter-filled universe, there are an infinite number of equally valid ways to measure its speed. Even if you use just other EM waves (other photons), you'll still get an innumerable number of ways to measure the speed of this one EM wave.