[kevonline]

I was wondering why everybody seems to think the universe is expanding? Apparently it's proven that galaxies are moving away at an accelerated speed.
Dark energy or antigravity with as a result the Big Freeze.

BUT what if we are actually already on the way back? Falling down back to where it started. As with debris from for example a vulcano, that can also come down accelerated and moving away from other debris and from the vulcano itself.

It would make much more sense (gravity)...
Is this possible?

I have heard of scientists seeing some form of light that in theory should have been closer to us than that it actually was. This can perhaps be explained as stars NOT on the way back yet, but still have some time to go before falling down.

Surely they must have thought about this, I am wondering what makes this theory less believable than the theory where we are still moving outwards.

[ebaines]

We know that the universe is expanding because galaxies that are farther away from us have greater red shift (i.e. longer wave length) in their light than do galaxies that are closer. This is known as Hubble's Law, named for the astronomer who first realized that the magnitude of the red shift is correlated with distance. Red shift is a good measure of the galaxies velocity away from us - the faster it is moving the greater the red shift. Conversely, if a galaxy is moving towards us we would see a blue shift (shorter wavelength) in its light. So it's not too difficult to tell that the universe as a whole is expanding. The rate of expansion is found to be approximately 72 kilometers per second per magaparsec - hence an average galaxy that is 1 megaparsec away (about 3.1 miilion light-years) would be receding form us at 72 Km/sec. However, within our own local group of galaxies the expansion is over-whelmed by the random motion of galaxies in space, and in fact Andromeda (our closest galactic neighbor) is actually moving towards us.

If the universe was shrinking we would see a blue shift in the light from far away galaxies, not a red shift.

For more info see: Hubble's law - Wikipedia, the free encyclopedia

[excon]

Hello kev:

Ebains is correctamundo!

You can get a sense of the "red shift" effect, by listening to a car approaching you, passing you by, and then heading away from you. All of those sounds are distinct and recognizable.

If you heard that, you wouldn't have to see the car at all to know what it's doing, would you?

excon

[kevonline]

ebaines, excon, thanks for your answers.
Just to let you know I am definitely not an expert on the subject, so please correct me on the following.

Think of objects that are falling down. The one that fell lets say couple of minutes ago will have a faster speed and acceleration than the one that just started falling down couple secs ago. The last one is just starting to speed up.
There will be redshift in this case as well, since the first one is moving away from the latter one (top one).

[ebaines]

Yes, BUT to an observer on the ground both falling objects will have a blue shift. Also, if objects are falling to a common point all the objects falling in from the other side of that point from where you are will have blue shifts. The only way for ALL objects to appear to have redshifts is for them all to be moving away from each other.

[kevonline]

I probably agree with you. The idea of an expanding universe seems more likely.
However...

Objects falling behind us are falling at a slower speed than we are, objects in front of us fall faster. So either of those objects will have redshift. We are moving away from the ones behind us and objects below us move away from us.
Objects falling to the center from the other side of that point (Big Bang), will indeed have blueshift, but who says that we can actually already see that far. Perhaps the center is as big as our visible universe and we can't see behind it.
I understand that we can already detect a faint glow, remains of the Big Bang, assuming this is around 360,000 ABB (after Big Bang ;)). But couldn't there be a whole lot out there on the other side of that glow?

Or :), what if that glow is like the crust of the universe and we are all moving towards it like a geyser or lava.

[ebaines]

And how would objects that are "falling" along side you appear? I'm talking about objects that are neither in front nor behind as you fall, but are off to the side falling at the same rate as you. They would have no red nor blue shift, no matter how far away they are. But what we actually oberve is Hubble's Law being followed no matter which direction we look. So again, your hypothesis doesn't match the observed universe.

[sarnian]

Objects falling behind us are falling at a slower speed than we are, objects in front of us fall faster.

Kev : there is hardly any 'in front' or 'behind' us in the universe.
Everything in the universe happens in the thin area of a spherical envelop (bubble) of space-time (not space itself).
We can not look straight from one side to the other side of the universe. We look through that thin area of space-time.

You can not refer to the effects of an explosion, as that refers to space, not to space-time.
The 'Big Bang' was not some explosion in space, but a strong expansion of space-time.
Everything there is, is in that spherical 'envelop'. There is no 'center' of the universe. We do not speed away from the location of the 'Big Bang'. We are part of the 'Big Bang'. That is also why the remnants of the energy of the 'Big Bang' is all around us (the 'glow' you mentioned).

So in general terms : which ever way we look, everything outside our local group of galaxies is moving away from us. Only on a local scale there is movement towards us. For instance the Andromeda galaxy is moving towards us (blueshift). But almost everything else is moving away from us (redshift). Only on an individual small scale - due to supernova explosions or black hole radiation - some matter far far away can move towards us.

So forget 'in front' or 'behind' us in the universe!

[xmlset]

kevonline it's a brilliant thought cheers to you for thinking outside the box. I had a similar thought this morning, looked up "the universe is falling and here was this page. Don't give up just because they are throwing data at you,

The thought of a universe "falling" like a spiral with fractal patterns of galaxies (mirrored objects of the whole) seems to have promise. It also might assist the theory of how information cannot travel out of it, and it is in fact (the universe) in a black hole, which is a theory many have been looking in to.

Anyway bravo kevon always question everything

[Titan69]

I have been thinking about this too, obviously or Google wouldn't have got me here, like you say if we were on a lava bomb ejected from a volcano all at once how would we see everything as it falls to the ground if there was never a ground to reach, everything would appear to be traveling away from everything else apart from those objects which would be about to cross your path, if the whole universe was falling at the same rate then nothing would appear to be moving, I also find it weird how we look at a solar system or galaxy from a side on perspective, why is that, if its speed and motion that keep us in orbit with the sun would it not be better to think of the equatorial plane as the north/south. Looking at the sun and gas giants their equators move faster, is this because they are being pushed by the rest of the matter around it as well as falling, so increasing in speed relative to its poles, if you turned the sun so its north and south were left to right the matter rotating on its equator would be falling faster than the matter at the poles. Could gravity not only be a field measured by size and weight but also the speed and movement of the matter being pushed or pulled around the central mass. I can't really explain what I mean in my head as words, I'm not a physicist but I do like to think of these things, one day I was working beneath a car burning off an exhaust bolt with oxy ascetaline, when the bolt melts to reach its critical point where the gravity takes it for a freefall to the ground it is comparative to the super critical mass of something in space under immense gravitational forces, as it hit the floor the weight pushing down explodes pusing matter outwards in a pattern very much like a solar system, so if you look at my little moment it is very much like a black hole reaching its maximum density, the point it cannot grow any further it would collapse in on itself ejecting mini pieces of super dense materials forming a galaxy. Could it not be that at the heart of every star/planet/atom there is a black hole, ranging in size from anything from a quark to a small planet, those small planet sized black holes wouldn't travel as far in the explosion so creating the denser clusters of space we see in the hearts of galaxies, where everything is on such a huge scale and moving in un imaginable speeds, is it not possible that a "black hole" is nothing more than the centre of everything. Why is it that the centre of our planet is moulten still after all of these years, could it not be that we have in fact contained in a crust the very essence of a solar system, where the magma is in fact orbiting a micro "black hole" (super dense material) creating friction movement and heat? Its a lot to think about no?

[Titan69]

Wish I could edit my post but the reason I got here was thinking about zero gravity or micro gravity in space, if everything is falling at the same rate then weight would be irrelevant, only when you push something faster than the rate of freefall would you create gravity in a weightless environment, like the plane (vomet comet) which falls at terminal velocity or the proposed gravity inducing rotation that is planned for space stations you are pushing faster than the freefall giving the feeling of gravity as you are being pushed from below, is zero gravity the lack of gravity or the feeling of everything falling at the same rate giving you the vomet comet ride through space, I hope this makes sense to everyone else too lol

[TUT317]

Hello Titan,

From your posts I think you are trying to establish one of the most famous debates in physics. Is time and space absolute or relative?

Newton claimed that that space wasn't affected by anything which happens in it, e.g. rotation and orbits of planets. In other words, space is the unmovable backdrop which we use as a frame of reference for all other objects. If an object could 'fall' in space then it would be easy to detect by way of the backdrop.

This was hotly debated at the time( and to some extent still is). Leibniz claimed that Newton was wrong.

Space and time make no sense except in terms of relative location of bodies.Leibniz was unable to prove this. It wasn't until Mach claimed that motion of bodies and mass only makes sense in relation the objects relative motion.

It is said that Einstein was influenced by Mach and from this he developed his ideas on relativity. Einstein thus showed that Newton was wrong. This is because space/time and the objects contained with are not constant and not independent of the observer.

Also I wouldn't place too much emphasis on things falling in space. Out of all the fundamental forces, gravity is very weak by comparison.

Others may be able to explain this better than myself.

Regards

Tut

[ebaines]

... is zero gravity the lack of gravity or the feeling of everything falling at the same rate giving you the vomet comet ride through space, i hope this makes sense to everyone else too lol

Titan - you are correct, in that "zero gravity" doesn't really exist. We commonly refer to objects in orbit about the earth as being "weightless," but strictly speaking that's not correct. The force of gravity from the earth at the altitude the space shuttle flies is just slightly less than the force of gravity on the earth's surface, and so objects "weigh" about as much is orbit as they do on earth. However, the space shuttle's orbit follows a curved path that in essence causes it to "fall" toward the earth at exactly the right acceleration to equal the acceeleration due to gravity - just like the Vomit Comet. Hence, objects inside the shuttle are all falling equally fast, and hence relative to each other act as if zero gravity.

[ptrparker]

What if you added magnetism and falling. This would push and pull as well as keep things organized.
Then add inertia, like jumping in an airplane.. the falling theory I thought was my idea until I goggled it..
Could this explain quantum physics? If a light source were falling and a light is projected on a still wall, the light would move. Like a proton in multiple places on the wall, or space?
This makes much more sense to me than an expanding universe. If I knew the fancy math, I would try and work it out..

ptrparker.

[zanderbaxa]

If the universe, as a whole, is falling, then the Hubble relations will still be there. We are in differenc frame then the BB, so all elements of our universe will be blue-shifted, releative to BB. Anything moving away from us will contune to move away from us, even when that thing and us simultaneouly reverse diection. This is anolous to our throwing a ball in front of us, even wile the ball and us are going backwards.

[zanderbaxa]

Supernovae vs big-bang

I have read thar our universe could not
Have started as a supernova because no
Heavy metals have been detected. I think
They have been looking in the wrong place.
Planets, stars, asteroids, comets and galaxies
Are the remnants of that expansion. If
They are not an agrgation of heavy metals,
What are they?

[TUT317]

what if you added magnetism and falling. This would push and pull as well as keep things organized.
Then add inertia, like jumping in an airplane..the falling theory I thought was my idea until I goggled it..
Could this explain quantum physics? if a light source were falling and a light is projected on a still wall, the light would move. Like a proton in multiple places on the wall, or space?
This makes much more sense to me than an expanding universe. If I knew the fancy math, I would try and work it out..

ptrparker.

Hi ptr,

Do you mean photon rather than proton? A photon is a massless particle whereas a proton has mass. Massless particles are better suited to light.

It is not so much that a photon can be in more than one place at a time but more of a case of light having both the quality of being a particle and a wave. Scientists talk about this unusual quality as a 'Superposition'


Tut

[TUT317]

supernovae vs big-bang

I have read thar our universe could not
have started as a supernova because no
heavy metals have been detected. I think
they have been looking in the wrong place.
Planets, stars, asteroids, comets and galaxies
are the remnants of that expansion. If
they are not an agrgation of heavy metals,
what are they?

Hi Zander,

Galaxies were formed a couple of billion years after the Big Bang. On that basis there was no star formation so there were no heavy metals in the very early universe.

Tut

[ebaines]

Planets, stars, asteroids, comets and galaxies are the remnants of that expansion. If they are not an agrgation of heavy metals, what are they?

Obviously there are heavy metals in the planets (and for purposes of this discussion the term "heavy metal" means any element heavier than lithium, so it includes non-metallic elements such as nitrogen, oxygen, carbon as well as classic metals such as copper and iron). What the astronomers are talking about is that they don't see such elements in the spectra of the very oldest stars. But they do see them in younger stars, like our own sun. These are remnants of nuclear fusion reactions that occurred in stars long before the solar system was formed. These elements were then distributed when the star experienced a nova, and were then available to be incorporated in the makeup of the sun and planets.

[zanderbaxa]

There may not have been heavy metals in our early universe; but, that does not mean there wouldn't be. Nucleosynthesis probably didn't start until our universe was cooler. Maybe our universe is in a
Gravitational bubble (black hole) and is one of many universes.