Gravity

[Bill Verburg]

string theory posits 10 dimensional spacetime, 9 physical and 1 time, the 9 physical ones are the 3 we are familiar w/ and 6 curled up ones that are needed for consistency w/ the reality we observe unfortunately there are 5 viable versions of string theory.

all 5 can be contained in an 11 dimensional mathematical construct called M Theory

one of the really fascinating things explained w/ all these extra dimensions is the conundrum of the disparity of the strengths of the 4 fundamental forces,

gravity @ 10^-64 of the strength of the E-M force is a real outlier.

one of modern Physics main goals is a Theory that unifies all 4 fundamental forces into 1

Electro-magnetic and Weak have been successfully unified, M Theory looks to be one of the better theories to unify the Strong and Gravity w/ Electro Weak forces

[island911]

Originally Posted by Pazuzu

... The expansion was rapid (many times faster than the speed of light) for several seconds, ...

I've always gotten a kick out of how time and space moved thru... wait, what did space move into faster than the speed of light? And did this for how long?

Originally Posted by Bill Verburg

angular velocity is the same at the poles and equator, instantaneous linear velocity(spin velocity, because the instantaneous v is accelerated into a curve following the arc of the earths surface) is not. At sea level at the equator, your instantaneous linear velocity is ~460 m/s on top of a mountain on the equator it is a bit faster. This is why the preferred orbital launch direction is to the east and the preferred location is a mountain top on the equator, Kilimanjaro or somewhere in the Andes , like Quito

Yeah, I get all of that, and know that you understand that too.

It's just that how you had written that point prior was ambiguous if not confusing (backwards?) for the typical reader.

[flatbutt]

Originally Posted by Crowbob

Oh yeah! I forgot about the Mexican hat potential. Things are gonna get really weird because we are definitely in another Inflation Era. It’s amazing how everything is connected!

It may be that our apelike brain is not yet sufficiently developed to cope with the reality of the universe......yet.

[Steve Carlton]

Originally Posted by stevej37

Isn't it kinda hot down there?

It’s definitely shorts and flashlight weather down there. One of those scarves you soak in cold water is worthwhile, too.

[Pazuzu]

Originally Posted by island911

I've always gotten a kick out of how time and space moved thru... wait, what did space move into faster than the speed of light? And did this for how long?

Space was not moving INTO anything. The anything ITSELF was what was expanding. It wasn't a case of an existing region, and the Universe was just taking up a larger section of it. There was no region, all of "region" was bundled up into the thing that was expanding. So, therefore, there is nothing "outside" of space, there was no pre-existing "thing" that space moved into, and no need for a prime mover. wink back at you.

As for faster than light, things cannot move faster than light though spacetime. Spacetime ITSELF has no such restrictions. The only problem with spacetime expansion is that information is lost when two sections of spacetime expand away faster than the speed of light...there was no communication across the Universe when Inflation happened. This was part of the decoupling, and why we cannot talk about what is beyond the Visible edge to the Universe. There's stuff out there, but any information has been lost between it and us, since spacetime stretched faster than light between it and us.

[stevej37]

Originally Posted by Steve Carlton

It’s definitely shorts and flashlight weather down there. One of those scarves you soak in cold water is worthwhile, too.

I might wear long pants...my legs burn easily.

[flatbutt]

Originally Posted by Pazuzu

Space was not moving INTO anything. The anything ITSELF was what was expanding. It wasn't a case of an existing region, and the Universe was just taking up a larger section of it. There was no region, all of "region" was bundled up into the thing that was expanding. So, therefore, there is nothing "outside" of space, there was no pre-existing "thing" that space moved into, and no need for a prime mover. wink back at you.
.

This is the part that makes my head hurt. It's difficult to visualize space being the entirety of existence with no borders up against anything else. I accept the red shift of the universe but how can it expand into nothing thereby creating more of something?
I'm accustomed to a finite existence. For the universe to expand my mind says that it must expand into another space or dimension.

As stated my ape brain is better at defining the limits that I will work within whether it be confidence limits or an LoQ specification.

[zakthor]

Originally Posted by Pazuzu

Space was not moving INTO anything. The anything ITSELF was what was expanding. It wasn't a case of an existing region, and the Universe was just taking up a larger section of it. There was no region, all of "region" was bundled up into the thing that was expanding. So, therefore, there is nothing "outside" of space, there was no pre-existing "thing" that space moved into, and no need for a prime mover. wink back at you.

As for faster than light, things cannot move faster than light though spacetime. Spacetime ITSELF has no such restrictions. The only problem with spacetime expansion is that information is lost when two sections of spacetime expand away faster than the speed of light...there was no communication across the Universe when Inflation happened. This was part of the decoupling, and why we cannot talk about what is beyond the Visible edge to the Universe. There's stuff out there, but any information has been lost between it and us, since spacetime stretched faster than light between it and us.

I thought we just discovered that gravity waves also move at speed of light - which is just space moving right?

I played this through in my head a few times and don't see why expansion had to be faster than C. Do you happen to have a thought experiment handy that explains why its necessary that expansion happened at more than c?

[Crowbob]

OK. Think of it this way, flatty.

You are in a room with furniture, lights, floor. A typical room. You know you are in a room because your body is sending information to your brain which interprets what your body is sensing. Information. Sounds, smells, images, temperature, even the passage of time, etc. Now as man has developed, our ability to gather information has expanded. Suddenly we can see further with a spyglass and see smaller with a magnifying glass. We can measure time and temperatures way beyond what we’ve ever imagined. Our ability to gather information grows. So now we are able to receive information beyond our own bodies’ abilities. We can detect electromagnetic radiation, magnetism, x-rays, infinite degrees of wavelengths of light, and so on.

Now imagine a place where there is no information. Not information that is out there that we don’t know how to receive yet. But rather no information. No gravity, no light, no radiation, no time, even. No nothing. There is nothing to be detected and no amount of technological advances can ever be able to detect it. Even if our most powerful telescope was on the edge of our known universe looking into space it would see nothing. There is nothing to see. There is no information. Just space without limit.

That is what the universe is expanding into.

[island911]

Originally Posted by Pazuzu

.... there was no pre-existing "thing" that space moved into, and no need for a prime mover. wink back at you.

...

Yeah, I wasn't trying to suggest a prime mover of some sort.

I mean that's just not believable.

Obviously... there was nothing, and then it exploded.

[Pazuzu]

Originally Posted by flatbutt

This is the part that makes my head hurt. It's difficult to visualize space being the entirety of existence with no borders up against anything else. I accept the red shift of the universe but how can it expand into nothing thereby creating more of something?
I'm accustomed to a finite existence. For the universe to expand my mind says that it must expand into another space or dimension.

As stated my ape brain is better at defining the limits that I will work within whether it be confidence limits or an LoQ specification.

We cannot visualize it at all, but mathematically it all makes sense. 4 dimensional spacetime, and we are a 3 dimensional universe within it. Dots drawn on the surface of a balloon (3D spacetime, 2D universe) all see the other dots moving away as the balloon expands, but none of them can calculate the size of the 2D universe, nor the edge of the 2D universe, nor the center of the 2D universe. Their 2D minds and basic geometry simply won't let them see or understand that their 2D universe is wrapped around a 3D object.

We are a 3D universe wrapped in 4 dimensions. We cannot see the edge, cannot find the center, nor can we determine the size of the universe, but it is still finite in size, and expanding in a mathematically understandably way.

Originally Posted by zakthor

I thought we just discovered that gravity waves also move at speed of light - which is just space moving right?

I played this through in my head a few times and don't see why expansion had to be faster than C. Do you happen to have a thought experiment handy that explains why its necessary that expansion happened at more than c?

Inflation didn't HAVE to happen, but it did happen. That flattened the Universe (make a circle, then make the circle REALLY BIG, and the surface starts to appear flat, not curved). Inflation make the Universe appear flat, not curved. It made the somewhat chaotic stew of matter very homogeneous, since quantum fluctuations which might have appeared as very high density regions got smeared apart under inflation. The distribution of matter that because galaxies and such was spread so thin, that it is now basically equal in every direction.

Originally Posted by island911

Yeah, I wasn't trying to suggest a prime mover of some sort.

I mean that's just not believable.
Obviously... there was nothing, and then it exploded.

There was the Higg's Field. That's not nothing, it was an energy field of negative potential energy that had a high enough value to spawn the Universe. How can you call that nothing?

[island911]

Originally Posted by Pazuzu

....
There was the Higg's Field. That's not nothing, it was an energy field ...

Wait wait... you just said there was no pre-existing "thing" that space moved into

[sc_rufctr]

Space and time didn't exist before the Big Bang. There was simply nothing before that event.

[island911]

n'no, there was Higg's field all the way down. (a little reference to the elephant tortoise explanation.)

[GH85Carrera]

Originally Posted by island911

n'no, there was Higg's field all the way down. (a little reference to the elephant tortoise explanation.)

It does not matter what any creation theory one prefers of the nearly infinite creation stories that every single group of people have. There was always a mysterious and un-explainable beginning. If you believe some entity was the creator, where did that entity come from? What created it? Same issue for all creation theories. With the current big bang theory, that there just was nothing before, as space and time did not yet exist. For all of human existence we have asked where did I come from, and where did the Earth and the stars come from.

The big bang is the only one with any math and physics to try to explain it, but the physics of the first few trillionths of a second all break down. No one has yet figured it all out with math. There is no way to test the theory. No one can say with any real proof one is the "Truth" and it all comes down to faith in math or the mystical. You get to chose what best fits your views.

[Bill Verburg]

The inflationary period is when the Universe expanded faster than the speed of light, causing local domains to lose contact w/ each other. We live in one such domain referred to as the observable universe as opposed to the total universe.


Things pop into andout of existence all the time.

It's called Random Quantum Fluctuation



In quantum physics, a quantum fluctuation (also known as a vacuum state fluctuation or vacuum fluctuation) is the temporary random change in the amount of energy in a point in space, as prescribed by Werner Heisenberg's uncertainty principle. They are minute random fluctuations in the values of the fields which represent elementary particles, such as electric and magnetic fields which represent the electromagnetic force carried by photons, W and Z fields which carry the weak force, and gluon fields which carry the strong force. Vacuum fluctuations appear as virtual particles, which are always created in particle–antiparticle pairs. Since they are created spontaneously without a source of energy, vacuum fluctuations and virtual particles are said to violate the conservation of energy. This is theoretically allowable because the particles annihilate each other within a time limit determined by the uncertainty principle so they are not directly observable.

usually

one place they do become real is at the event horizon of a black hole, where 1/2 of the virtual pair escapes and the other 1/2 is absorbed into the black hole, This observable effect is called Hawking Radiation and eventually leads to the total evaporation of the back hole.

One Theory of the Big Bang is that it is at least similar in nature to such a quantum fluctuation.

[Crowbob]

Ok. So if all physical laws break down at the quantum level, doesn’t that mean that something other than what can be described by physical laws happened?

What does one call something that happens outside physical laws?

[Bill Verburg]

Originally Posted by Crowbob

Ok. So if all physical laws break down at the quantum level, doesn’t that mean that something other than what can be described by physical laws happened?

What does one call something that happens outside physical laws?

The many Universes Theory posits multiple universes each of which may have it's own unique laws

In our universe based on what we know now there are 26 constants that define the universe


If any of these are the least different it changes the entire universe and other universes can have different values

[LEAKYSEALS951]

[Crowbob]

So are you suggesting, Bill, that because there may be multiple universes is cause enough to conclude ours doesn’t exist? This universe, the one we live in, appears to be the result of something outside this universe’s (the one we live in) physical laws.

The multiverse theory looks to me to be a clever way to rationalize the inability of quantum physics to explain how we got here. Here, in the universe we live in.

Even then, since we are talking theory, what if all those other universes also appeared from their own definitions of nothing?