Physics

[LiamOS]

A lesser purpose of this thread is to allow members to ask questions about physics which they need clarification on or want an explanation on.

In my time spent here, I've been told many a time how conventional science fails and falls short in areas. As such, I decided to make this thread. However, as there are many on the subject of Biology and its many branches, I felt one to address the issues in physics would be appropriate.
For the purposes of this thread, physics covers Nuclear Physics, Particle Physics, Astronomy, Cosmology, Relativity, Quantum Mechanics(QCD, QED...), Electromagnetism, Optics and Thermodynamics.
The conventional theories in each field will be taken, in the context of this thread, as the best explanation currently available:
The Big Bang, the Standard Model(Particle physics), etc.

Questions for debate:
-Other than that which we do not yet know(Higgs Boson, etc.), are there any significant shortcomings in the conventional physics of the day? If so, where and why?
-Some theories are based on underlying assumptions. Are any of these assumptions flawed or not necessarily true?

With our current knowledge of the universe from a physicists point of view, is it logical to infer than a deity is a necessity? Why or why not?

On a final note, this is a physics thread, so don't hold back on using mathematics as support for your hypotheses.

[LiamOS]

We know there was a really hard core expansion at the beginning, it was probably the strong force becoming notable.
However, that result doesn't mean that light travelled that fast or that anything else did, only that space expanded that quickly.

[Grumpy]

AkiThePirate

I am far from a real expert in physics, for one thing math gives me headaches(real headaches). I understand most of the ideas, but have to just trust the math beyond a certain level(say High School level, I can do better, but don't want to). True physicists in the theoretical areas are bound to be a little strange to us mere humans, every other word they use assumes you know things that only a small fraction of the population knows. Of course doctors, engineers and Wall Street traders are exactly the same way. The the depth of current human knowledge is so far beyond the capacity of a single human you could look at it as the difference between a single cell(knowing only what it learns and experiences first hand)and a multicellular creature with specialized organs for separate functions or as the evolution of human society, whatever.

Anyway, what I am about to say is my understanding of what physicists now know...

The Big Bang was an expansion of what we now call Dark Energy. It is a mysterious force/pressure/energy? that acts exactly the opposite of gravity, pushing outward on spacetime(which it is the source of). With nothing to oppose it, and no speed limit yet established it "inflated to incredible size(I've seen estimates as high as 75% of the current size, we don't yet know)within fractions of a second.

Gravity was "frozen" out(a phase change)when temps dropped enough. When gravity/mass exist light speed was established and the inflation halted and became instead expansion. Gravity restrained the Dark Energy, and, as the density was high, the initial expansion was, relatively, slow. As the expansion "diluted" the power of gravity the expansion has been speeding up.

The energy of the BB also created matter(E=MC^2)in a rather complicated dance between matter and antimatter, with a slight excess of matter. We ended up with ~5% matter(the stuff we are made of and we can see), ~20% Dark Matter and the Dark Energy which accounts for ~75% of the mass of the Universe.

Where did all that energy come from? Well, since the original "singularity" erupted out of the Quantum realm(smaller than Planck length, width, heighth and time)we may get clues from behavior we see from that realm today, especially Quantum fluctuations in energy and the creation and annialation of particle pairs. These fluctuations in energy can be any size, and the particle pairs any mass(though the smaller, the more probable). And, particle pairs appear in pure vacuum, where there is no energy or not nearly enough to produce the real mass of the particles. That makes no difference, the pairs exist, therefore they must be "borrowing" the energy of their annialation from their own future! Not only is there no cause for the pair popping into existence, but their annialation energy follows their creation from that energy.

Now, I am about to go a little off the reservation here(though I can still see it from here), but can the Universe be living on energy it will pay back in the future?

We have three dimensions of space, we can move in two directions in all three. But we can only move in ONE direction in time, toward the future. Does that mean it is HALF(1 direction/2 possible directions)a dimension?

M theory postulates 11 dimensions, the four we are aware of, the rest "rolled up" in the Quantum realm. Some are thought to be "space like", some "time like", and some are just strange(the theorists lose me somewhere around here, "If you cannot think in mathematics, you need not apply.").

The space like dimensions are said to have zero length(or of "indeterminant" length as Quantum mechanics says), but every point in space is connected to that same dimension, deep down in the very small. This is what leads some to postulate instant travel, teleportation etc. being possible, by short cutting into other dimensions.

Now imagine a half dimension of time that is "space like" and of zero length, but that only connects every point in space time to one place in the past, the Big Bang(IE the ultimate point in past time). So we would have time as we know it in the macro world, balanced by it's opposite(in duration, direction and size)in the Quantum realm.

Now, where, in all of the time since the Big Bang, do we see matter, energy, space and time all descending into the Quantum realm?

Black Holes.

Grumpy

[LiamOS]

Good post.
I'm almost the opposite to you. While I can grasp ideas to a certain extent, if I'm shown the math it makes far more sense. It's both a blessing and a curse.

As to the universe being based on 'borrowed energy', that's an interesting idea. Quite similar to Lawrence Krauss' hypothesis presented in 'A Universe from Nothing'.

[Grumpy]

AkiThePirate

Lawrence Krauss' hypothesis presented in 'A Universe from Nothing'.

Yes, Krauss was one of the books I looked at that led me to the conclusion that it was a real possibility.

As to the math, those that can, do, those that can't, teach. I taught.

Grumpy

[LiamOS]

Krauss' books are usually quite good.
As for teaching, you only have to understand what you teach. And from what my American friends have told me, High School math and physics isn't the worlds most demanding course, which is a shame.
It's been getting steadily worse in Ireland, too.

It's a little worrying to me that most people who come out of the educational system didn't actually benefit in any way from their math or physics education.

[myth-one.com]

We know there was a really hard core expansion at the beginning, it was probably the strong force becoming notable.

This expansion explains various properties of the current universe that are difficult to account for without such an inflationary epoch.

What we know is that the hard core expansion is required to support present theories. That's the only way the data makes sense to us at present.

However, that result doesn't mean that light travelled that fast or that anything else did, only that space expanded that quickly.

Light didn't travel that fast.

Neither did anything else.

But space did.

Space isn't anything? Expanding implies travelling to me.

In laymen's terms, how do you picture that working? Does the empty space get "created" or whatever; then is populated by plasma, energy, matter, whatever -- later? How can you imagine that "nothing" was there before the space was "created?"

Thanks

[LiamOS]

What we know is that the hard core expansion is required to support present theories. That's the only way the data makes sense to us at present.

In astronomy, astrophysics or cosmology, that's almost as good as knowing; they're not what you'd call 'exact' sciences yet.

Space isn't anything? Expanding implies travelling to me.

Well, for lack of a better way to phrase this, you're wrong.
Space doesn't really expand at a speed, because for speed you need a distance, which changes as the expansion happens. It's a weird phenomenon.
Again, though. If the universe's expansion continues to accelerate, it's not just going to stop at one point.

In laymen's terms, how do you picture that working? Does the empty space get "created" or whatever; then is populated by plasma, energy, matter, whatever -- later? How can you imagine that "nothing" was there before the space was "created?"

Cosmology's a tough one to put in laymen's terms. I'll try, though.
You know those things in airports that are like escalators but flat? This thing:

Let's say we have two of these next to each other moving in opposite directions.
Imagine I'm standing on one, and you on the other. We start right next to one another, and drift apart. However, we're not moving with respect to the thing(Which represents space), but the distance between us is growing.
It's this sort of thing that means nothing travelled faster than light. Nothing moved that distance in space, but 'space' was growing.

Sorry if that's a poor analogy, but it sounded much better in my head.

[fredonly]

Let's say we have two of these next to each other moving in opposite directions.
Imagine I'm standing on one, and you on the other. We start right next to one another, and drift apart. However, we're not moving with respect to the thing(Which represents space), but the distance between us is growing.
It's this sort of thing that means nothing travelled faster than light. Nothing moved that distance in space, but 'space' was growing..

One of the more interesting feature of space expansion is that points in space can separate from one another at a rate that exceeds the speed of light. As time goes on, astronomers will be able to see fewer and fewer galaxies because the expansion will be faster than their light can travel to us.

[fredonly]

Questions for debate:
-Other than that which we do not yet know(Higgs Boson, etc.), are there any significant shortcomings in the conventional physics of the day? If so, where and why?

Yes - Modern physics (cosmology) does not have a generally accepted theory about the origin of the universe. They start with 10^-44 seconds after the point of singularity (which cannot be an actual point in space-time). There are various hypotheses (multi-verse; oscillating universes; the "universe from nothing" ) but they are highly speculative and may not be testable. I'd say this is the closest that science comes to religion...because it's a gap that might possibly never be filled by Physics (despite the enthusiasm one hears from some of the folks involved in the speculations). Unless progress is possible and is made, the speculations begin to sound a bit like faith.

-Some theories are based on underlying assumptions. Are any of these assumptions flawed or not necessarily true?

The various pre-big bang theories are based partly on speculations that are not verified, and possibly cannot be verified.

With our current knowledge of the universe from a physicists point of view, is it logical to infer than a deity is a necessity? Why or why not?

No, at least not in the sense of conventional definitions of a deity. A sentient, active deity raises more questions than it answers.

On a final note, this is a physics thread, so don't hold back on using mathematics as support for your hypotheses.

1 and 1 is 1. (this is a test)

[myth-one.com]

1 and 1 is 1. (this is a test)

1 and 1 are 11. (Proof left to student)