If 1/2 the Earth dissappeared what would happen to the Earth / Sun orbit?

[g__day]

I discovered this interesting question on another forum where folk where missing the correct answer.

The situation is simply if half the Earth just dissapeared, what would happen to the Earth / Sun orbit; would the Earth speed up or slow down, move closer or further away from the Sun?

It's actually a very good question to consider, because it requires you to think broadly.

To start at the basics the Earth is falling towards the Sun with a force proportional to G * Mass of Sun * Mass of Earth / average seperation distance ^2, and this is balanced by an outwards replusion equivalent to Mass of Earth * Velocity ^ 2 / average seperation distance.

Now half of the Mass of the Earth just vanishes in a moment of quantum pique, what happens and why?

[Starkler]

Nothing happens because on both sides of the equation mass is a direct multiplier, so a change in mass gives an equal and linear change to both the centripetal and gravitational forces, so they remain balanced.

Can you imagine an astronaut in the space station with a salami floating around which he then cuts in two and releases. The two halves will not shoot away from the earth to find a new orbit ;)

[g__day]

Which was exactly the thinking that most folk on the other forum finally arrived at. Neither bodies velocity nor momentum changed.

Now can you think deeper and see why what you have just said isn't what actually happens!

A small hint - your salami or Astronaut model isn't the right framework. Image half the salami just popped out of existence - so matter and energy weren't necessarily conserved. Neither's velocity nor momentum is affected but how has your system changed?

Hint

Imagine in the Earth / Sun example its was the Sun, not the Earth that suddenly diminshed by 50% of its mass, would you still say your logic works or can you see where the gotcha is?

[Shawn]

I think it depends on which half, doesnt it,, :D If the top half dissapeared for example would anyone notice,,,;).


S

[[1ponders]]

When m1(sun) is much greater than m2(planet), nothing will happen because the speed of orbit is determined by the semi-major axis of orbit. Kepler determined that the Period of orbit squared is proportional to the semi-major axis cube. (In the case of the sun and planets P^2=a^3 )

For objects of similar mass then Newton modified Keplers law to


P^2= [4pi^2 / G(m1+m2) ] a^3

Where G is the universal gravitational constant (still not accurately known :rolleyes: ) and a is the semi-major axis of the orbit and P is the orbital Period.

[Shawn]

Ah Paul thats a lovely equation, and accurate to boot, but forgive my prior humour, the question was half the planet dissapeared, not decreased in volume by 50%. now we have introduced something thats not in your equation.

Unbalanced centrifugal force. axis shift..and its influence on nearby objects.

[[1ponders]]

If half the planet disappeared, it would eventually form an ovoid shape again under gravity anyway.

An easy way to prove this is to tie a sinker to a piece of string and swing it around your head at a velocity that just keeps the string horizonal. Do exactly the same thing with a ping pong ball with the same length of string. Different sizes and different weights but the period of orbit stays the same. (allowing for increased wind resistance of the ping pong ball)

Mass doesn't enter into it. Which falls faster; a hammer or a feather?

[Shawn]

eventually it sure would, but in the interim the centre of mass has changed by a few tens of miles to a thousand miles. depending on what bit dissapeared. the string length has changed.

S

[[1ponders]]

Not appreciably thought. The earth is only about 6,380 km in radius, the earth/sun semi-major axis is 150,000,000 km. Or roughly a ration of 4.253e-5/1. The effect would be a very minor shift, if any.

If the near side disappeared the earth would slow down ever so very slightly, and if the farside disappeared the earth would speed up ever so very slightly. Too late in the night to work it out but I'll have a look at it in the day light :P

If the top or the bottom disappeared it would have no effect.

[Shawn]

Thats what I said, If the top half dissapeared, nobody would notice,,,:D.

Goodnite Paul..

Be Well..

S

[ballaratdragons]

OK, I'll think outside the box!

If half the Earth suddenly dissappeared the world would break apart and disinigrate!

This would be caused by the unbalanced shape being thrust around it's axis causing severe stress on the odd shaped remaining half.

P.s. Geez I like the job Mojo and I did on my new Avatar :lol:

[g__day]

Guys that's pretty good thinking. I could keep hinting but maybe its better to inform.

From a Newtonian point of view the system is unchanged. Both bodies have no net change on the other as determined above.

But we don't live in a Newtonian world...

The system has lost rest mass, so the systems gravity well has diminished. So whilst the planets motion through spacetime doesn't change the curvature of spacetime itself does change under relativity when mass or energy is suddenly lost!

So you would see within this frame of reference the orbit slightly, but discernible change (expand and become more eccentric).

So whilst Kepler and Newton where giants, Einstein does come into play in some cosmic games!

[xelasnave]

Gravity rain predicts as there is less shielding available the gravitational influence is less and the orbit will seek a larger radius:shrug: .. but GR will always agree with space time so whatever Dr A says is fine with me:thumbsup: . GR is the stuff that does the actual bending you see;) .
alex

[[1ponders]]

I can agree that the orbit will be ever so lightly larger. My previous change in center of mass was wrong. It wouldn't be 6380km, it would be less than half that. Making a guestimate of an increase of 1300 km (for various reasons and ignoring the fact that this is way smaller than the difference between the earths semi-major axis and semi-minor axis AND the earths orbit isn't circular) I get an increase of about 30 min added to the standard earth year of 365 days.

I would be interested in how the change in the earths orbital eccentricty with change, considering is it continually changing anyway (over a 40000 year period that is)

[xelasnave]

We are presuming that when half disappears that half the mass goes with it...
What if the halving is confined to volume and not mass... mmmm If mass is not halved it seems nothing should change.
alex

[ving]

Id have thought one of the major changes would be the gravitation point where the earth and moon rotate around? maybe this point would now be outside the earth body... either way it would change the way the moon rotates around us and in so changing the orbit around the sun...

i am no astro physicist but this make sense to me :)

and when you say half, i automatically thought layers from the outside. that would leave the molten core exposed to space cause i dont think there would be any ozone layer or atmosphere or anything....
gah! my head hurts :P

[[1ponders]]

You are probably right ving. The problem is trying to work out the results for a three body system. With a two body system (sun/earth) it's relatively ( :P ) easy to solve. A three body system is an entirely different kettle of fish, though with the earth and moon being much less massive than the sun the overall average orbit probably wouldn't change that much. Different story for trying to determine the orbit of a planet around two similar mass suns :eyepop:

[g__day]

Mass (or Energy, which is its equivalent) have some relativistic effects on any frame of reference. Increasing mass slows time and increases the curvature / geometry / bendiness of space.

Think of a large 3d volume of space, say a sphere, that would readily contain the Earth and the Sun. Say a sphere of radius 10 light minutes centred on the Sun's point of suspension. Well that volume isn't just a mathematical volume regardless of if its empty or not. Under relavity the space itself actually changes at the physical level, it curves as it becomes more massive. The opposite is also true, lose mass and the curve straightens. Whilst you can have a straight line in maths easily, in space there is no abstract straight, straight depends on where your mass and energy densities are localed and their magnitude!

Spacetime itself changes and so do all the paths through this volume. Minutely but certainly detectably at the supposed mass loss in this experiment.

Space tells matter how to move and matter tells space how to curve...

PS

And yes as mentioned above the Bary centre of the Earth / Sun pair would shift towards the Sun further, meaning the Earth would be orbiting at a slightly increased distance from the Sun too.

[xelasnave]

G day you no doubt are aware of the use of the ball on the rubber sheet being used to demonstrate the concept of how mass bends space. I contend that the example is misleading and humbly seek your input if you are prepared to comment.
I feel the ball on the sheet example has the ball on the wrong side of the sheet... if one left the sheet and the distortion of the sheet in place as if the ball were upon it but moved the ball "under" the sheet would this not be a fairer representation of the way space is bent? Or another way of putting this.. take a "straight" grid line I think it bends towards the mass point not as the example demonstrates "bent around it". I see a lot of representations of gravitational lensing that has the grid line bending around the mass point as opposed to being bent towards it.
A very curious alex

[g__day]

Hi Alex, nice ask I will try and answer.

First think of gravity as an aspect of geometry rather than a force. Second realise that the Universe is always trying to be more chaotic and dis-orgainsed (increase its entropy levels - which generally means not pack things into a smaller volume of space in a more ordered fashion).

Now the sheet analogy is a way of trying to visualise a 4D piece of geometry in a 3D world - something which is really hard to do! You are replacing the invisible force with a visual element of geometry meant to represent what really underlies the nature of our reality. Throw a ball or fall of a cliff and you are seeing geometry of spacetime, not a force in action - all very hard to come to grips with.

If I had to answer how do we visualise gravity as a 3d geometry, I'd start by saying remember 2d circular log paper - which looks like an old fashion radar screen? Well imagine that in 3d with a mass being at the epi-centre. So to a distant observer the lines showing how far 1 centimetre of distance is are smaller as you get closer to the point source of mass.

So spacetime is more curved the closer you get to a point of mass. A lightyear of distance could look like a micron to a distant observer of spacetime very close to a black hole's event horizon.

Similarily when you get very, very, very close to the baryonic matter that comprises the nucleus of any atom (protons and neutrons) you'd expect the gravitational curvature of spacetime at distance less than 10 ^ -20 metres to be rather extreme given G is inversely proportional to a 1/d^2 effect.

We don't really undertstand theoretically how the four forces interact at these very close distances to atomic matter. Say that again - our best scientific models can't apply and describe what happens very, very close to the nucleus of an atom. In a certain way a proton may have its own gravitational event horizon - if its density (volume / mass) is above a certain level. We can't model these happenings yet, at best we move from relativist physic (which is exotic at time) to quantum mechanics - which is the equivalent of relativity on LSD. Under QM particles can be in two places at the same time, very often (called tunnelling), and interfere (differaction) with each other, and appear and dissappear etc...

So after my long set up rant, my responce to your question - the volume of space has to be geometrically more distorted closer to the concentrated centre of mass (or energy). So yes you could use a bowling ball on a sheet of foam or you could consider helium balloons released inside a large circus tent. All will want to travel towards the apex.

Rather than lines to or around a point soure of mass, consider space and distance shrink as you get closer to mass.

* * *

PS - where this thought experiment was heading and how it ties into dark energy / dark matter

The loss of mass in a closed system leading to no change in a Newtonian / Kepler framework, but a significant change to a relativistic framework is where I wanted folk to head. Throughtout school and most of our life we see space as a fixed entity that only Captain Kirk (or Piccard) moves through easily, as if he was going down to the corner store, or driving across country.

But space isn't always like that. If on a cosmic scale matter can be created and destoyed without apparently conserving energy or momentum, in finite spots for a finite time, then there is a different framework for studying cosmic expansion other than dark energy or dark matter (or perhaps offering a candidate for them).

Hawking has showed its possible for matter or energy to jump from the cosmic foam (alah the world of the really tiny quantum mechanics that our universe appears to float in) and not necessarily spell doom and gloom. Hawkings initial postulate was a pair of virtual particles (pro and anti to conserve mass and energy) tunnel into our reality then immediately zap each other and annihilate... except if they appear near the event horizon of a black hole, so one escapes and one is sucked in. In this situation you've just added mass and energy to the Universe.

My thought experiment was a simple two body test of what are the effects of a sudden large extract of mass from the universe - answer spacetime uncurves and we can detect this change in an an otherwise unexplained shift in the orbit of planets. The sun is losing mass every day as its converted into energy and it radiates past us. So spacetime around our solar system is uncurving (very, very, very slowly) every second of our lives.

But what if around galactic centres matter is coming into existence? Physicists studying MOND have shown you only need a very small adjustment to explain why galaxies don't fly apart. Calculated as if this force was attributed to mass gain you need about 1 hydrogen atom per cubic metre of space per year. Theoretical physics has shown that empty space should contain about 10 ^ 120 Joules of energy per cubic metre, the greatest whoopsie in the framework of our thinking - or is it? What if that energy is there - but it manifests very, very slowly over all time - not just all at once? If there is that much potential energy, but in only leaks in in the form of 1 Hydrogen atom per year, maybe all parties could reconcile some pretty wierd theories.

But all that at the moment is just pure theoretical spectulation with no solid grounding - yet. But as said the thought experiement was to get folk thinking and have them realise space, the final frontier, is not a constant, but a variable dependent on localised mass and energy.

[xelasnave]

Thank you for taking the time to explain it in such depth.
I percieve space time as more geometry than anything else. What I am asking I will put another way... short of a drawing ..with this crude description. Say we have a sheet of "graph" paper to represent uncurved space time. In the centre of our page we place a point of mass.. I guess what I ask do the squares become "smaller" (although curved) the closer to the point of mass.
alex

[Karls48]

Very interesting tread. I think that if half of Earth disappeared there would be huge explosion as the mass is converted to the energy. Even if there were possible way to make half of the Earth to disappear without converting matter to energy, there would be still explosion, as angular movement of large mass would be instantly destroyed. The other half of the Earth would be blown to dust and scattered over Solar system.

[g__day]

Alex

Yes - the squares near the mass would not only appear to get smaller - they would be smaller! The speed of light may be a constant but time certainly isn't and distance = speed * time, so distance is relative too!

Karls

Possibly, if every second atom simply tunnelled through into another reality (or back to the quantum foam) Newton would turn in his grave. By his understanding energy and momentum would have hugely been violated (and possibly no bang occurs) - as there is no conversion, matter simply fades away into another reality. Einstein meanwhile would shout Eureka and modify relativity to say M-Theory is right, there are multiple realities and there must be away to send matter or energy from one to another. So energy and mass and momentum would be coversed (within a transformation function from one reality to another) across membranes / dimensions.

[sheeny]

Paul,

Haven't you made an additional assumption there about which side of the earth has disappearred? What if it was the "outside" (relative the earth) half?;) Or just for the sake of playing... the "inside" half (the core)...:D

Al.

[sheeny]

So the equivalence of matter and energy (E=mc^2) is bunk????:shrug:



I follow the argument but don't agree with the conclusion that matter and/or energy is added to the universe. Is not the black whole part of the universe? While the cosmic foam concept allows us to explain the average statistical behaviour observed at macros scales and reconcile it with quantum theory, each matter/antimatter pair is not serial numbered to only cancel with the partner it was created with.

If an antiparticle is annihalated inside a black hole the gravitational effect outside the black hole does not change (due to mass/energy equivalence).

Al.

[g__day]

No, e=mc^2 (in simplified form ignoring momentum for particles with no rest mass), seems pretty solid, but I was saying in a quantum mechanics framework matter or energy can do very, very wierd things - we're do you think that the Universe came from under the Big Bang if it wasn't a quantum fluctation of extraordinary magnitude?

And if a pair of opposite virtual particles get created and one is swallowed by the black hole so the other escapes as a real particles then the universe now has a higher energy density +1 to normal spaceimte in the universe and +1 to blackhole. For the blackhole's gravitational field increases even if anti matter is swallowed (unless I'm just entirely sleep deprived)!

Is a blackhole part of our Universe? Well at least partly it must be. By this I mean it exists in a reality beyond relativity within its event horizon (say for instance the inside is at the energy densities that it is a realm entirely ruled by quantum gravity and the four forces have re-combined back into one). It is unclear then how this inside the event horizon interacts with normal spacetime ruled by relativity, or any other realities beyond spacetime within our universe that it may be connects with.

[sheeny]

Who knows? A "quantum fluctuation of extraordinary magnitude" may be one possibility, but it's a particularly unpleasant one to consider IMHO. If our universe was created this way, then there is an anti-universe somewhere just waiting to annihalate ours, and it could do so at any time without our ability to detect or predict it. It is in the realm of philosophy not science.



No, sorry, I don't agree. For the the quantum foam to produce the matter/antimatter pair, the energy had to exist in the universe anyway. For every such pair produced in this way, is it not just as likely that a pair was absorbed by the cosmic foam in the same way? I'm not aware that quantum fluctuations are not an irreversible process. Statistically, quantum fluctuations cancel out.

So I suggest, if the matter/antimatter pair were separated as you describe, the anti particle would annihalate a corresponding matter particle to produce energy, but the total amount of mass/energy in the universe (including the black hole) remains constant.



My interpretation is that a black hole is part of our universe, albeit a part we cannot observe the inside of from here.

I know Hawkling has produced mathematical models of what goes on inside black holes but these are even bordering on philosophy. It is all done with extrapolation of the laws of nature as we observe them. As I imagine you are well aware, extrapolation is much less precise (and sometimes very dangerous) than interpolation. Until we work out a way to observe through the event horizon, any theories about what is on the inside of a black hole are far from concrete, because the conditions there differ so immensely from the conditions in which we have developed the laws of nature. Philosophically, all sorts of things could be possible, but scientifically we can say it's a black hole and speculate about what's inside. I have no idea if there's any other sort of "reality" inside a black hole... maybe it's more of the same (simply unable to be observed due to the extreme curvature of space/time at the event horizon), maybe it's bizarrely different. The question is a philosophical one based on today's science.

Al.

[AGarvin]

Hi all,

Hope you don't mind if I chime in and say a few words. Hopefully I'm understanding where some of the debate is coming from.

With regards to QM and virtual particles, conservation of energy is maintained due to the uncertainty principle. While most know this as the relationship between position and momentum, there is also the relationship between energy and time. Two virtual particles can be created so long as the time they exist does not exceed a certain limit. The greater the energy of the particles the shorter the time they can be in existance before they annihilate and give their energy back to the vacuum.



When two particles are "created" at the absolute horizon of a BH, and one enters the horizon, the other then becomes a real particle with positive mass and energy (+1 so to speak). The particle that enters the horizon therefore has negative mass (and therefore negative energy), so takes mass away from the BH (-1). The energy density balance in the universe does not change. This is the principle behind Hawking radiation and related black hole "evaporation".



Correct. It's what is known as vacuum energy. It's a "fluctuation" in this energy that causes the virtual particle pair creation.



Hi Alex, the squares become longer in the radial direction, but narrower in the "width" direction as they get closer to the mass. The ball on the sheet analogy can be confusing as it's a 3D representation of a 2D plane. Imagine the sheet as being totally flat, and on this flat sheet are the paths that an object can take (distance), but the effect on the object is as though it's on the curved aspect of the sheet (time and acceleration).

Cheers,
Andrew.

[Kal]

I would say if half the earth disappeared then some scientist at some facility would have a hell of a lot of explaining to do as to 'what went wrong?!'

:einstein: :atom: :earth:

[xelasnave]

So it appears that I have a fair view of the grid as it were. AND certainly the ball should be under the sheet to even represent that situation.
AL said...
I know Hawking has produced mathematical models of what goes on inside black holes but these are even bordering on philosophy...
I salute your braveness to say such but the truth stands irrespective of the greatness of the man who that may undermine.
His position is very much he can speculate (albeit with presumably sound math models) however in truth he is more of a philosopher than a scientist when in this area for what really goes on at present is beyond observation so ideas will remain simply ideas..my little understanding of scientific methods tells me that it is not a theory until observation support the "idea" and I don’t know that very much of his input does that... mind you his view is not to be dismissed but I think many, because of his intellectual might, are afeared to say what you have said. Congratulations.
Anyways I have noticed so many drawings, artist impressions of light being represented being gravitationally lensed.. it seems to me that who ever is behind many (al I have seen or noticed) have the ball on the blanket concept as the only way they can work with the concept..because "space" is curved around the ball , or in the drawings the object responsible for the gravitational lensing.
I mean the light comes along directly toward the gravitational lensing object then moves out into space and detours around it..so as to produce the effect in the blanket and ball world..I say that view is wrong.. as would anyone when you look carefully at such artist impressions.
alex

[sheeny]

G'Day Alex,

Please don't think I'm trying to undermine Hawking!!!:lol: He has an exceptional mind! But when you push the boundaries as he does, sometimes the boundary between science and philosphy gets crossed... it's just something we have to recognise and live with until we can move the boundary out around it - by either proving or disproving the idea. Basic scientific method.

Al.

[xelasnave]

No I did not think that ...and I say similar which is possibly interpreted as impertinent but you have called it right. He is a great mind but that does not entitle him to very much more in the speculation department than the rest of us..indeed it entitles him to less in my view. But he is a mighty mind no one can ever take that away from him.. still you are more aware than me, I expect, that you not only have to be clever you have to have observation and experiment.. without which it really is not science I recon.
alex

[xelasnave]

To refresh ...I said..
Anyways I have noticed so many drawings, artist impressions of light being represented being gravitationally lensed.. it seems to me that who ever is behind many (al I have seen or noticed) have the ball on the blanket concept as the only way they can work with the concept..because "space" is curved around the ball , or in the drawings the object responsible for the gravitational lensing.
I mean the light comes along directly toward the gravitational lensing object then moves out into space and detours around it..so as to produce the effect in the blanket and ball world..I say that view is wrong.. as would anyone when you look carefully at such artist impressions.
What I am driving at if you lay over a grid and the grid lines get "smaller" nearer the "mass" the space time grid suggests to me that light would follow the grid lines, in which case they move towards the mass and when passed the mass move out again. I know the drawing is probably simplified to get the idea across but at that level I see it inconsistent with how space is bent by mass. The illustration and indeed the ball on the blanket approach would see a bend in space that went on forever like placing a bend in a piece of paper.
alex

[xelasnave]

Here is my view of the way it must work. I am not making a statement as much as questioning what I understand about my space time understanding. Please ignore the grey that is something that crept in trying to merge ovals in word star:D
alex

[g__day]

PS

I don't take Hawking as gospel, he is merely trying to construct a theoretical / mathematical model for the pyhsics of extreme environments that definitely go beyond relativistic environments. He is stating possible rules for his construct - which we are a long way from scientifically proving yet!

PPS

I must re-read the black hole envapouration scenario - as I didn't get that the "swallowed" virtual particle has negative mass = negative energy = negative entrophy. That gives me a fair headache.

[xelasnave]

I understand his importance and respect him for his struggle with life, he needs recognition for that if nothing else:thumbsup: , but I find some of the black hole radiation thing a bit hard to swallow:shrug: ..but I dont speak math or physics so what would I know:shrug: . I find the concept of black holes at the centre of our galaxy somewhat irrelevant as it seems their mass is not sufficient to really be responsible for holding the galaxy together. Their exsistence to me is a little like dark matter ..comes from theory and the observations sortta back up the theory.. but we still cant see one;) .
Where ever the balck holes are I can not imagine they are at the centre..if two they will form a binary orbit and if more ???..well it matters not they will be destined to orbit the centre not be the centre of the galaxy. Even if one its mass relative to the rest of the galaxy means it will orbit the centre as oppossed to being in the centre. I often wonder therefore if there is a real hole scribed out by the orbits of the inner most black holes.. somewhere the gravity rain can shuffle from one side of the system to the other:lol: :lol: :lol:
Hopelessly irrelevant but that has never stopped me before:lol: :lol: :lol: .
alex

[xelasnave]

Why an actual hole??? I just cant see an individual black hole making the jets that come out of the galactic "centre" whereas a binary or more system would make a very efficent vortex to propel matter as we observe...using the hole I suggest of course.
alex

[g__day]

Just a note about my major annoyance with black hole discussions:

Accepting there are singularities within the event horizon as a foregone conclusion derived under a non applicable physics model annoys me immensely.

Under relativity nothing stops matter, energy and spacetime from being crushed into a singularity within the event horizon, but its pretty clear relativity doesn't apply within this framework - so why apply its dictates at all?

Model what can happen under quantum mechanics, quantum gravity, loop quantum gravity, SuSy etc

Treat three (?) dimensional space, one dimensional time (?), the equivalance that are matter and energy, which affect properties of both the shape of spacetime and the rate that time passes at a given locale within said spacetime as complex interrelated variable and come up with a scenario that works.

As it stands this singularity as a foregone conclusion is really sloppy science from my perspective. I'd rather it be called X and unknown and try and model it out.

Even the work on massive grav-stars showed if during collapse your sun had massive spin (angular momentum) then a singularity could be avoided.

Personally I think you're going to end up with some pretty wierd, interdependent framework as all the variables interact with one another so they are all kinda self referential. Think about it mass is meaningless without time and space to exist within. Same goes for energy. But energy and mass shape both space and time so they must be able to both move within it, and shape or change it as they move. Mass and energy must interact with both each other and time and space. We still can't model what happens with these interactions when one or more of these properties gets either really big, really small, really heavy, really energetic. At a quantum level all our sciences break down and we need a way of fixing this before we talk about what happens in this domain.

So lets be crystal clear - the four forces affecting matter and energy (gravity, electomagnetism, strong nuclear, weak nuclear) - don't interact clearly in any sort of describable, sensible fashion once you get down to distances that are the size of an atom or smaller! All our powerful, modern physics breaksdown at this level and you really do have to transition to the very wierd and incompletely understood world of quantum mechanics (things appearing, dissappearing, tunnelling, being in more then one place at one time, not always absolutely conserving mass nor energy, not every having a specific location, inbuilt uncertainity dominating their actions, never being at absolute rest etc ... acting probablistically) to model reality. Until we better understand the interactions between all the dynamic changes to the geometry of spacetime and things within it at both the nano and macro scales - our physics and understanding of reality is very incomplete.

My brain is full, can I go home now sir?

[xelasnave]

Well I am doing my best to come up with TOE but I have had to put it to one side to get the grass mowed. Hawking said at one point he gets about 3 TOE's in the mail each day so if nothing else people are trying and thats good.
All will be solved when gravity rain becomes the popular view so we need not worry really.
The one thing I have learned on my wanderings trying to find out answers available re gravity is there is a lot of science out there that is no better than a form of religion. So many propositions are presented without what I am told to do each time I present my ideas. I wonder why high proofs are demanded to prove contrary yet if supporting the current popular view they are readily seen as supportive. I dont think I am the only enquirer who suffers from morosophia in fact my condition appears less extreme than many presenting views.
Thanks for your tollerance and understanding and the gems you reveal to me. You can go home but keep thinking about a solution.
alex

[sheeny]

G'Day g_day,



Just remember the name - relativity. Relativity describes the appearance of the black hole to us from the outside by virtue of the distortion of space and time around the enormous mass of the "black hole". It can't alone describe what is happening inside the event horizon. Maybe the best we'll ever do at describing the inside of the event horizon is speculation.



:lol: Yeah... These sorts of discussions are extremely difficult in this type of forum IMO because the written word alone is very limiting, and we are all from such different backgrounds that's it's hard to establish the common ground to build on without confusion.:P

Al.

[g__day]

Yeah,

But given within a black hole Relativity => Singularity, but relativity doesn't apply, why not say you get layers within the event horizon as the four forces combine back into 3, then two then one force of quantum gravity as energy densities increase towards the core - and if you keep going you get to a portal back in time or to extra dimensions - it would be just as unfounded as the singularity argument. I'd rather just hear our physics models don't go there so we have no idea of either the geometry nor the force carriers and the forces involved!

[AGarvin]

G'day G__day (sorry dude, I had to repeat it .... :P ).



But relativity does apply. The whole concept of a black hole singularity is a direct result of General Relativity. No GR, no singularity. It's GR that says we get the singularity, remembering that the physical singularity is nothing more than General Relativity reaching a mathematical singularity. General Relativity works fine inside the event horizon, it's at the point of singularity that it mathematically hits infinity and breaks down, but so does quantum mechanics, which loses it at the Planck scale.



Remembering that relativity is a geometric theory, this is essentially what we're saying when we say "singularity". By its very definition singularity means "can't go any further coz it's all turned to #### :doh: ".

It's also not missed by theoretical physicists that the General Relativistic Schwartzchild radius of the quantum Planck mass doubled (ie the diameter) is conveniently equal to the Planck length, its Compton wavelength. While QM and GR seem to be at odds, there are strangely in bed together. This is why theoretical physicists are beside themselves trying to unite the two theories beyond this point. Both QM and GR break down to Newtonian physics at macroscopic and non relativistic scales, and rightly or wrongly it's expected that whatever theory goes beyond must breakdown them.



Absolutely. Discussions can often be taken as a personal attack which is not the case.

Cheers,
Andrew.

[ballaratdragons]

I still like my answer! :lol:

Sounds feasable to me :)

[xelasnave]

That’s certainly neat Ken but if we say disappeared it would be necessary to remove the mass of the “missing half” otherwise we would have to take it into account. The problem often arises in mind exercises like this it becomes more complex the more you think about it and of course its not long before we get to singularities. Having enjoyed a specualtion top arrive at a point we then add detail. Simple answers are dictated by the razor so I recon you win it.:thumbsup:
From what I have read it seems that part of being a leading scientist is to be subject to personal attack and the reason is simple ..If you are a leader in the field and you speak the truth and your conclusions are based on solid ground you will be hard to throw in an argument about which you are a leading authority, personal attack will be all that remains for someone challenging the top gun as it were:eyepop: . So if under personal attack be happy they can beat you with real facts;) . Hows that for a happy view on life?:D :D :D
Having said that I hope I never give offence because I don’t ever intend to hurt anyone’s feelings, if I ever offend it is probably an attempt at poor humour:P . I like to keep my input as simple as I can and have may be most readers under stand it:) .
Thinking about the problem as to event horizon etc may not be necessary in the real world. The problem is more one of how to record the physical than to say what it may or may not be doing. The singularity grows from necessity of fitting numbers to our safe ground established by experiment and really how to record the matter.. However this creates a limit imposed really by humans not nature :D ..If you see my drift;) . The plank limit is a limit of qualification and the fence line our imagination must sign off. So what I propose I suppose is the squares we use to get a geometric impression simply get smaller and smaller and smaller without any singularity being reached…Just because light cant pass the event horizon does that mean anything should change about the physical content of a black hole. Does not the problem really arise from placing a dot on a sheet of paper and giving up when you can see it anymore.. It is my belief that notwithstanding the theory and “boxing” of particles we think we have it all.. The barrier of singularity need not exist in the real Universe and in our attempt to fit particles in their boxes we stand at a barrier put there by ourselves:) . Needless to say science can only move forward on solid ground but even Mr Hawking has this uncross able barrier before him.. It has been noted the different backgrounds here and that is very true and say I have an unsteady grasp on what I think I know but I have an ability to get overviews I suppose. Anyways think about it this way we build a singularity out of math and have established “an event horizon” where conventional math breaks down .. Can we get rid of it????? I respectfully ask? Simply for a speculation on what may be happening down there even if the math must follow? And a geometric regression may fix it all:lol: :lol: :lol: .
alex

[ballaratdragons]

All interesting, Alex. Luckily I know where you are coming from. :thumbsup:

What amazes me is that all the theories being thrown around by Scientists in our Modern up-to-date world could and probably will be laughed at in the future: "did those poor mis-led creatures really believe that stupid theory".

Just as we now laugh at the flat Earth, and Earth being centre of the Universe.

Our modern theories could be so far out that they will seem unthinkable in 50 - 100 years from now. Hmmmm . . . interesting!

[xelasnave]

Oh Ken have you pushed my “hot button” by accident or on purpose:D ? That reference to a flat world I see when I see the rest of the world viewing the force of attraction as a fact rather than a human invention:lol: :lol: :lol: .. when I look at the Universe and try and perceive the ramifications to current knowledge it is mind boggling:P :D . I am so convinced I am on the right track I feel the future will find it hard that we could not realise that although attraction presented to us it was simply our incorrect perception;) . They will see us like we see flat world people:whistle: . I morosophically see it that way so it is easy to gather supporting evidence but it comes from an unhealthy interest in how does gravity work on a nuts and bolts system. AND yes its late and wild thoughts abound:P :D .
Thinking further about the necessity for things.. could it be that there is indeed not a black hole as we see it in our science.. I thought about the idea above of the effect of a binary black hole system and that system could work with two large mass Suns and possibly exhibit a Mass greater than we can work out. Is not the black hole a product of the space time geometry? As opposed to a sample of a live one? Thinking about it in nature it would not make sense to have what we conceive as a black hole.. or if it were there it must have an extraordinary purpose.. other than a place to cram matter. I therefore wonder of how one could actually fit a black hole in a Universe and I like more of the big Sun Binary System fooling us into thinking we have found a black hole:shrug: . I wonder how big they would have to be to fool us would be one way of killing that one dead eh:D ? Still I love to think about it but being good at Chemistry in fifth class does not qualify me to be able to provide all the answers.. well not all this week anyways:lol: :lol: :lol: .
alex

[xelasnave]

and drifting further into dream land (I cant sleep dam it..) but when one thinks of the way galaxies line up a literal hole in the centre of a spiral would make sence. Now I know I am dreaming. Good night. One more look at the weather and to bed.
aklex