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# Earths Absolute Velocity

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if it where possible to pinpoint an exact position in space ( but im not sure if this is possible because of expansion) could you then calculate earths net velocity relative to this 'stationary' point? if so has this been attempted?

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There are no fixed points in space. Velocity can only be measured relative to something else. Here are some examples:

Earth's average orbital velocity around the sun: 29.8 km/second relative to the sun

Astronomers sometimes find it convenient to imagine that there is a sort of fixed point in space as you have described. For example they will refer to the Local Standard of Rest (LSR). This is an imaginary circular orbit around the galaxy lying within the Galactic plane. At our distance from the galactic centre a star that followed that orbit exactly would be travelling at 220 kms per second relative to the galactic centre.

The Solar system's orbit is not exactly circular (nor does it remain in the galactic plane). So, it has a motion, relative to the LSR, towards the constellation of Hercules, of between 17 and 22 kms/sec.

Our closest large neighbour galaxy is the Andromeda galaxy. We are approaching it at about 140 kms/second and will eventually collide in around 3 billion years.

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A relativistic universe has four distinct distances: luminosity (inverse square), angular diameter, parallax, and proper motion. No two of them need agree to maintain consistency. Clocks can only be synchronized by being local. Pick a point, measure a Doppler shift, get a number. It's mathematically consistent but is it physically meaningful? Depends on how far away the point is and how much accuracy you need.

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If there was a big bang then there must have been a center. Why would this view be inconsistant with anything?

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If there was a big bang then there must have been a center. Why would this view be inconsistant with anything?

The Big Bang did not occur at the center of the universe, it occured at every location in the universe.

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If there was a big bang then there must have been a center. Why would this view be inconsistant with anything?

Space itself grew out of the Big Bang. In other words, if the universe and all its components were compressed to a pinhead, which exploded and subsequently expanded, space was tied to this pinhead as well. And space has been expanding ever since as well. So, as Aki said, in an expanding universe, every cubic millimetre was the core, location, and origin of the Big Bang - therefore, every point in the Universe is static, and the rest of the Universe is in motion relative to that point. It's the space between the points that's stretching. I have to add that this is only theory and conjecture, and can change when the next Einstein makes his appearance.

To confuse you even more; you live in a different universe than I do. The edges of your universe is a couple of milliseconds off-set from the edges of my universe, seeing as you're on the other side of the world. Each individual therefore inhabits a different universe, althoug the practical volume of everybody's universe intersects, so it doesn't matter in the least. It's just a cool thought.

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That's ridiculous. "The bigbang point" was probably moving too. Its possible that we are moving at lightspeed or not moving , only moving in time...That was what relativity said, right?

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That's ridiculous. "The bigbang point" was probably moving too. Its possible that we are moving at lightspeed or not moving , only moving in time...That was what relativity said, right?

I think you need to read up on relativity, chatlack. Anyway, this has been discussed at length before.

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Sorry. I could have made a mistake.I think I mixed up some theories. :rant:

But its the part that fits my opinion.

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That's ridiculous. "The bigbang point" was probably moving too. Its possible that we are moving at lightspeed or not moving , only moving in time...That was what relativity said, right?

...moving? Compared to what? What else was there that was moving at the time? Nothing? Exactly. There wasn't anything else to judge velocity by. I know - it's counterintuitive, but that's the way it works... :rant:

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If there was a big bang then there must have been a center. Why would this view be inconsistant with anything?

The Big Bang was not an explosion in space, the Big Bang was an explosion of space. All 4(pi)steradians of every point in the universe exactly points to the Big Bang. EVERY point in the universe is at its exact center. At the end of every direction in which you look, that's the Big Bang.

Reality is not Euclidean, Galilean, or Newtonian. Live with it.

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I realize this is the current view, but does't it leave a little bit of a sour test in your own personal logic, it does mine. One problem I have is that if the universe is a sphere this view grates on my nerves, if it is a torus I can understand it.

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ok so relative to a fixed point is pretty much impossible because there are no 'fixed points' so how about relative to our local group of galaxies? if someone told me where i can get the data then i guess i could do it myself...

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I cant understand why people say "space" to area that galaxies exist. Space is everywhere for me. Saying "space is an area" is logically wrong, i think.

Space is not groving, galaxies passing through it....

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If there was a big bang then there must have been a center. Why would this view be inconsistant with anything?
The center of what? There was nothing there. After the bang, it was everywhere - no center. The universe is not a sphere.
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One problem I have is that if the universe is a sphere this view grates on my nerves, if it is a torus I can understand it.

It is not a sphere. In fact, the shape of the universe comes in many flavors depending on what theory you subscribe to.

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I cant understand why people say "space" to area that galaxies exist. Space is everywhere for me. Saying "space is an area" is logically wrong, i think.

Space is not groving, galaxies passing through it....

Okay. Then *what* is space? And *where* is it? ;)

(And how can galaxies be moving through it if it is *not* what the galaxies exist in)?

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