Gravity foam and quantum fluctuations

Lbeard

I was thinking about gravity waves. Say the waves generated by a large body orbiting another large body.

When the waves break down, I imagined there would be gravity foam (like sea foam from waves at sea).

Does this mean space is full of gravity foam? Or does this happen?

If the foam is at the Planck length...Would it be the cause of Heisenberg's energy uncertainty?

When gravity waves move through space, do they dissipate energy? I was thinking of vacuum fluctuations. If there's pair production in the vacuum, the moving wave might be able to separate the pairs before they have a chance to annihilate. Would there be a signature radiation?

Lbeard

Am I completely wrong headed in this idea?

locum-motion

Well, I can tell you that foam - on the sea or in your dishwasher or in your shower - is a phenomenon caused by surface chemistry at the surface between two dissimilar chemicals, and the other chemicals that are dissolved in them. It is not caused by waves (although agitation causes more of it)

I really don't know what you mean by 'gravity foam'.

Lbeard

locum-motion wrote: »

Well, I can tell you that foam - on the sea or in your dishwasher or in your shower - is a phenomenon caused by surface chemistry at the surface between two dissimilar chemicals, and the other chemicals that are dissolved in them.

I am not talking about bubbles.

It is not caused by waves (although agitation causes more of it)

I'm talking about agitation. If you have a perfectly still lake on a windless day, the surface will look smooth and flat. Fill the lake with pleasure boaters, even if there's no wind, the wakes of their boats will add up causing the surface to be no longer flat, but more like a the sea on still day; lots of mini waves going in all directions.

I really don't know what you mean by 'gravity foam'.

You mean you Googled it and you found nothing. Or the only link was this thread. Welcome to the cutting edge of science, my friend.

I used the term Gravity Foam, to make it sound close to Quantum Foam (Which if you google, Wikipedia do have an entry)

locum-motion

Lbeard wrote: »

...You mean you Googled it and you found nothing. Or the only link was this thread. Welcome to the cutting edge of science, my friend.

I used the term Gravity Foam, to make it sound close to Quantum Foam (Which if you google, Wikipedia do have an entry)

No, I didn't google it. I meant precisely what I said (unlike you).

locum-motion

Lbeard wrote: »

I am not talking about bubbles...

Oh are you not? So, why did you say this then?

Lbeard wrote: »

... (like sea foam from waves at sea) ...

Since I have obviously so completely misunderstood you, would you care to try again to explain your concept? And perhaps this time avoid using similes that you don't actually mean to use.

Capt'n Midnight

Lbeard wrote: »

I was thinking about gravity waves. Say the waves generated by a large body orbiting another large body.

When the waves break down, I imagined there would be gravity foam (like sea foam from waves at sea).

First of all a reminder that you can't have pair production in a complete vacuum because you need something to take away the momentum.

You imagine gravity foam. If it's to be more than cool name / mismash of diverse theories it should make some predictions or explain some things.

Gravitons ?

Lbeard

locum-motion wrote: »

Oh are you not? So, why did you say this then?

Because you went off on one about chemistry..........And I believe bubbles may be possible too. I think they're allowed by the maths of General Relativity. Bubbles aside for the minute.

Since I have obviously so completely misunderstood you, would you care to try again to explain your concept? And perhaps this time avoid using similes that you don't actually mean to use.

Okay for the sake of visualization, as it's difficult to imagine 3 dimensional gravity fields and gravity waves. So for the sake of trying to think about it, to picture something in my head, I know it's incorrect but it's just a visualisation. I'll explain.

Let's forget gravity exists for the moment. Imagine all bodies are half submerged in a sea. Imagine a huge planet half submerged in some liquid (I'm subsitituing gravity for this liquid). It has an orbiting moon. As the moon orbits, it leaves a wake like a boat* in the gravity liquid - the waves of the wake travel through space. And this is where you get your gravity waves. This is just a away of thinking about it. Imagine a lake with lots of these planets and moons, the surface of the liquid would eventually become choppy - there would as be choppiness in the volume. With gravity there is no surface - it's just volume.

*A difference with gravity and water wakes, is that a body traveling through space creates a wake in front of it as well as behind.

Lbeard

Capt'n Midnight wrote: »

First of all a reminder that you can't have pair production in a complete vacuum because you need something to take away the momentum.

Okay. this is largely accepted, also largely disputed*. Heisenberg's Uncertainty Principle is largely accepted. I can't do latex on this machine to show the formula, but Uncertainty Principle implies, kind of obviously, that the uncertainty is not just in momentum and position, also energy, and you could stretch that to gravity.


This is the theory of quantum foam. That there is minor energy, gravity etc fluctuations - bubbles, loops, everything.

Vacuum production does not violate the conservation of energy. To use a liquid analogy (this is not real liquid, it's magical imaginary liquid to illustrate the Uncertainty Principle). For any spontaneous bump going up in the still surface, there is a corresponding anti-bump going down. The up and down bumps exist for a short time and then cancel each other out. There is no free energy from the vacuum.

Hawking radiation from a black hole, is when a one bump falls into the black hole and its' anti-bump can't annihilated it, so it escapes. The bump that falls in the hole, annihilates energy in hole, causing it to shrink. Energy in the universe is conserved.


*the dispute, is there is no experimental evidence of Quantum Foam. some Photons arriving from a distant stellar event, like certain types of super novae, should be slightly out of sync, since they're not traveling through a pure vacuum, but a spatial foam. But there are also good reasons to believe the foam does exist.

You imagine gravity foam. If it's to be more than cool name / mismash of diverse theories it should make some predictions or explain some things.

Even Einstein aside, some form of gravity wave has to exist. Think about your own gravity field. As you walk towards somebody, both your gravity fields produce a wake (in front of you, as well as behind), as you walk away, the fields change . Gravity moves at the speed of light, the amplitude of the waves will diminish very rapidly, but they will travel very far. Once their amplitude falls to below the Planck level, I imagine they become part of the foam. Though if they add energy to the foam, for energy to be conserved the quantum foam must release energy. Imagine you are a surfer, you are out at sea with a surfer friend, you're both still in the water. A wave comes but for some reason your friend doesn't catch it, but you do. You reach the beach, while he's stuck at sea.

Gravitons ?

There's lots of problems with the idea of Gravitons. According to the observations of General Relativity, masses distort empty space/vacuum. So if Gravitons exist, if they are the force carriers of gravity, then they have to act on the vacuum. To keep everything quantised, empty space must also be constituted of little quanta of nothing, but that nothing must interact with the gravitons.

Capt'n Midnight

[QUOTE=Lbeard;84855967

I can't do latex on this machine to show the formula,

just use tags in your post [Latex] x^2 [/latex] [latex]x^2[/latex]

Vacuum production does not violate the conservation of energy.

you have to conserve momentum too

locum-motion

Lbeard wrote: »

Because you went off on one about chemistry...

Can I suggest you have another look at the chronology of the thread, and who said what in which order?
The bit about 'sea foam' was in your original post, so you can't have said it in response to me 'going off on one' about chemistry.

locum-motion

I'm gonna hold my hand up here and say I'm out of my area, it's all flying over my head. I'm out.

Lbeard

Capt'n Midnight wrote: »

just use tags in your post [Latex] x^2 [/latex] [latex]x^2[/latex]

you have to conserve momentum too

p = mv

Kinectic energy

[latex]E_{k}= \frac{1}{2}mv^{2} = \int p \ dx [/latex]

Heisenberg

[latex]\Delta p\Delta x \approx h [/latex]

[latex]\Delta p \approx \frac{h}{\Delta x} [/latex]

[latex]\Delta \int p \dx \approx {\Delta} \int \frac{h}{x}[/latex]


That was a struggle. I'm using a crappy distro of Linux that doesn't like my keyboard.


There is something even more freaky and cool in there if you can see it.

Lbeard

The freaky bit is

[latex]\Delta mv\Delta x \approx h [/latex]

[latex]\Delta m\frac{dx}{dt}\Delta x \approx h [/latex]

See time is there. If there is an uncertainty in all quantities, then there is an uncertainty in time. And since the delta [latex]\Delta [/latex], moves positively as well as negatively, in the Planck volume, time can run backwards.

And of course gravity can go positive and negative too. As [latex]Gravity Acceleration = \frac{d_2x}{dt_2} [/latex]

If anyone would like to disagree, disagree.

Duggys Housemate

Well there is nothing new there, not knowing a particles momentum or position exactly means you don't know it's time to get somewhere exactly which you are demonstrating. And all physical laws have no "direction of time". That's a higher level property caused by entropy ( if it even really exists). There is no "now" in any equation.

Voltex

Lbeard wrote: »

The freaky bit is

[latex]\Delta mv\Delta x \approx h [/latex]

[latex]\Delta m\frac{dx}{dt}\Delta x \approx h [/latex]

See time is there. If there is an uncertainty in all quantities, then there is an uncertainty in time. And since the delta [latex]\Delta [/latex], moves positively as well as negatively, in the Planck volume, time can run backwards.

And of course gravity can go positive and negative too. As [latex]Gravity Acceleration = \frac{d_2x}{dt_2} [/latex]

If anyone would like to disagree, disagree.

Would I be right to say that there may be nothing in the equations to say time cant run backwards...its just highly improbable or that time is a parameter rather than an observable?

Duggys Housemate

There is nothing in any equation I know of where time can't be reversed ( it would be like saying if you replace t with = 10s, you then can't replace t with 5s)

Direction of time is not in any equation.

Justin1982

Lbeard wrote: »

I was thinking about gravity waves. Say the waves generated by a large body orbiting another large body.

When the waves break down, I imagined there would be gravity foam (like sea foam from waves at sea).

Does this mean space is full of gravity foam? Or does this happen?

If the foam is at the Planck length...Would it be the cause of Heisenberg's energy uncertainty?

When gravity waves move through space, do they dissipate energy? I was thinking of vacuum fluctuations. If there's pair production in the vacuum, the moving wave might be able to separate the pairs before they have a chance to annihilate. Would there be a signature radiation?

Gravity on the large scale (based on General Relativity) and the associated gravity waves should really be taken with a small pinch of salt. I'm not overly impressed with experiments that claim to confirm existence of gravity waves.
As for quantum gravity, well you should take that with a large pinch of salt also even if big names like Hawking claim theories like M theory are the final answer. I havent seen too many experiments that back up any of the theories of quantum gravity and any of the theories that do exist are probably still at early stages.

Lbeard

Voltex wrote: »

Would I be right to say that there may be nothing in the equations to say time cant run backwards...its just highly improbable or that time is a parameter rather than an observable?

I'm not sure, to be honest. All I think is the appearance of time at that level would be definitely fuzzy...maybe.

I need a more rigorous verification. I have a rough idea what I need to do...hit the maths books.

Duggys Housemate wrote: »

There is nothing in any equation I know of where time can't be reversed ( it would be like saying if you replace t with = 10s, you then can't replace t with 5s)

Direction of time is not in any equation.

It's over much short time intervals then seconds. It's down at the Planck scale so the time intervals are very small.

I don't know.

Duggys Housemate

Lbeard wrote: »

I'm not sure, to be honest. All I think is the appearance of time at that level would be definitely fuzzy...maybe.

I need a more rigorous verification. I have a rough idea what I need to do...hit the maths books.



It's over much short time intervals then seconds. It's down at the Planck scale so the time intervals are very small.

I don't know.

The t being seconds is not relevant. It could be any value. There is no direction of time in any equation except entropy calculations.

Lbeard

Justin1982 wrote: »

Gravity on the large scale (based on General Relativity) and the associated gravity waves should really be taken with a small pinch of salt.

I believe the gravity waves have to exist.

Think of a planet, 3 light minutes away. It has a huge moon - that does a complete orbit in 6 minutes. From where you are, you can measure the gravity of the moon. When you see the moon, your measuring device tells you the gravity is at it's max, when it's behind the planet, it's minimum. But think about what your seeing. When you see the moon in front of the planet, at that moment in time it's behind the planet. In what form does the gravity propagate thrown space? It has to be a wave.

Your measuring device will show you a sine wave.

Think about it, it's hard to visulise but once you do it's hard not to have gravity waves.

I'm not overly impressed with experiments that claim to confirm existence of gravity waves.

I think they're using a binary star system. If the stars are orbiting each other, the system will act like a gravity oscillator. The main draw back is the amplitude of the wave falls very quickly. If you knew what system they're trying to measure, then using Newton's gravitation law you could calculate the amplitude of the wave.

Capt'n Midnight

Lbeard wrote: »

I believe the gravity waves have to exist.

Think of a planet, 3 light minutes away. It has a huge moon - that does a complete orbit in 6 minutes

6 minutes :eek:

what sort of density would the planet need to have a moon outside the Roche limit

https://en.wikipedia.org/wiki/Roche_limit

If the primary is less than half as dense as the satellite, the rigid-body Roche limit is less than the primary's radius, and the two bodies may collide before the Roche limit is reached.

https://en.wikipedia.org/wiki/Hill_sphere may also worth looking at when considering gravity propogations

Justin1982

Lbeard wrote: »

I believe the gravity waves have to exist.

I dont believe in anything to be honest.
The only thing that exists for me is a theoretical derivation or an experimental result that can be replicated and confirmed.

GR theoretically looks good but its not rock solid on the quantum scale. Even on the large scale where its considered to be an exact model of gravitation, I'm not 100% convinced. Despite all the experiments that confirm its predictions, its totally conceivable that it could be altered same as Newtons theory.
Gravity waves have only been indirectly observed. So until they are directly observed by experiments currently in operation then I hold a neutral stance. I replace belief with "I reckon there is a 80% chance" that gravity waves will be detected or whatever confidence I have in the theory.

Lbeard

Justin1982 wrote: »

I dont believe in anything to be honest.
The only thing that exists for me is a theoretical derivation or an experimental result that can be replicated and confirmed.

The existence of gravity is hard to dispute. It has to have a speed, and then all you need is an appropriate moving body to observe the waves. You definitely need something on the astronomical scale.

I don't know if direct gravitational observations have been done of planets in our solar system. But if there have been, if the gravity conincides with the light then it is travelling in a wave.

GR theoretically looks good but its not rock solid on the quantum scale. Even on the large scale where its considered to be an exact model of gravitation, I'm not 100% convinced. Despite all the experiments that confirm its predictions, its totally conceivable that it could be altered same as Newtons theory.

There's a good chance its' incomplete for large scales. Dark matter sounds like a huge fudge.

Gravity waves have only been indirectly observed. So until they are directly observed by experiments currently in operation then I hold a neutral stance. I replace belief with "I reckon there is a 80% chance" that gravity waves will be detected or whatever confidence I have in the theory.

A good question would be why haven't we seen them already. There's examples of gravity lensing, equally I would assume that we should see instances of lensing through waves.

Voltex

Just so Im clear...the notion of gravity waves is just an abstract mathematical function describing the propagation of an elementary and hypothetical graviton particle?