MigL

I do remember reading about this years ago but I can't give a source after all this time. Basically at low energies particles are not energetic enough to get close to other particles such that they 'see' each other's true field strength. This happens because particles surround themselves with a multitude of virtual particles which pop in and out of existence.. An electron for instance, would be surrounded by positive and negative charged virtual particles, and for a brief instant, the positive charges would move closer to the real electron before vanishing. This migration of positive virtual particles towards the electron would 'screen', or mediate, some of its true charge, and we would detect it to be less than it actually is. At higher energies such as the GUT scale ( about 10^15 GeV IIRC ), particles are energetic enough to reach inside the virtual particle screen and see the true strength of that particle's field. At this temp the particle's field strength are all equal ( if you include supersymmetric virtual particle contributions of course ).

According to GR black holes conserve the properties of mass, charge and angular momentum. QM considerations also lead to the conservation of other properties such as entropy. For the OP we can disregard all but mass and charge since the others aren't affected by whether they are matter or anti-matter. Since mass is always positive and negative mass is a theoretical construct, it is always additive irrespective of matter or anti-matter or even if a particle is its own anti-particle.. Charge on the other hand, can be positive or negative for matter or anti-matter, so it is additive or subtractive like positive and negative numbers.

But if individual universes in the 'multiverse' are related through the time dimension, then they are also causally related. In effect they are not separate universes, but parts of the same single universe. I've always had a problem with the multiverse model. If something is not causally related and can never affect us or be detected in any way, does it make any difference if it exists or not ?

Well if the slow roll inflationary model is still the benchmark ( didn't know there was an encyclopaedia inflationaris ), why doesn't anyone speak of multiple inflationary periods. I would think there would be one after each symmetry break. The latest would be the electroweak break where EM decouples from the weak nuclear. The previous would be where the grand unified breaks and the strong ( colour ) nuclear decouples from the electroweak at approx. 15 GeV ( IIRC ). and there may even be one where gravity decouples ( this one is still undecided depending on the nature of gravity ). And if each inflationary period leads to a causal break from the previous epoch, how can we possibly proceed backwards along the timeline to get closer and closer to t=0

As I said I agree with your earlier post and thank you for the additional references. I just wanted to make it clearer for everyone that heavier particles, being higher energy, start being created earlier in the timeline, at higher temperature. And I still would not have included photons and neutrons in the model due to the reasons given previously. Haven't really given much thought to the eras before the symmetry breaks, but don't some models predict inflationary periods following a symmetry break due 'rolling' down from the false vacuum zero energy level. I believe Guth's original inflation made use of this mechanism.

Thanks John and Mordred, a quantum particle has a definite definition , but it's not a classical particle or a wave. A lot of the wave/particle duality results depend on the experiment set-up. If you set-up detects wavelike behaviour you will 'see' waves, and if it detcts particle like behaviour, you will 'see' particles. Just like looking at pictures of your extinct animal from different directions John.

Are you sure you want to include neutrons in that Mordred ? All primordeal neutrons would have undergone decay as thy were not stabilized in nucleii at this time. All present day neutrons are the product of recombination in later ( lower temp ) eras. If that wasn't the case we'd still see massive particles around, maybe even magnetic monopoles. Are you sure you want to include photons in that Mordred ? The photons, or radiation, are what the massive particles are in thermal equilibrium with. They would be present throughout the particle creation/destruction era in various ( decreasing ) energies. One point I'd clarify is that production of massive particles actually starts earlier, but thermal equilibrium quickly ensures that just as many are destroyed as are created. It is only after they drop out of equilibrium due to cooling that that the reverse order of lighter to heavier takes over. Not implying you're wrong by any means, just thought it needed some clarification and re-consideration.

If I may elaborate... The satellite is, in effect, falling. A fall with no horizontal component, such that it falls through the centre of the earth, is in orbit, If it has enough horizontal component, it goes right around the earth, still in an orbit. This is simple Newtonian gravity. What GR adds is that an object in free fall, such as an orbit, has and feels no forces on itself. If it has no forces acting on it, it experiences no acceleration ! And Orodruin is absolutely right, your weight, i.e. the force you feel, is not due to gravity pulling you down, but from the ground pushing you up.

Further to what studiot and swansont have already pointed out, causality is directly dependant on time, i.e. effect must fallow cause. I fail to see how memory can be the cause of an effect and how causality doesn't apply to non-intelligent objects.

You write sci-fi Moontanman ? Amateur or professionally ? And if professionally, anything we might have read?

Holy c*ap you're old studiot !! You must be 100 yrs old if you studied physics before the discovery of sub-atomic particles and the development of QM. Just kidding !

I've heard about the new methods also, so maybe in time the results won't be as skewed towards larger/closer planets. As to how many planets can share close orbits, it seems to be extremely large for small asteroid as in between Mars and Jupiter in our own system. However I suspect as the asteroids become larger approaching planetoid size, tidal forces would rip them apart as they pass close to each other in their close orbits. Someone better at orbital mechanics than me would have to give you an approximate answer as I don't think an exact answer is possible.

Are you suggesting, Fred, that quantised measurements are solely dependant on the receptors and that the emitter produces continuous and NOT quantised values of energy ? Congratulations, you've just re-introduced black body UV catastrophy and poor Max Planck is spinning in his grave.

Since planets are detected by perturbations of their parent star, they would, by necessity, have to be very massive or very close to their star in order for the perturbations to be detectable. Until methods become more refined, the vast majority of found extra-solar planets will have these characteristics.

A dimension allows us to relate two different events. As an example Alaska and Siberia can be related events in space-time, as the two events were connected by a land bridge of a certain length about 15000 yrs ago. Not a physical model, but Fred is absolutely right.

Its not a matter of the object's own frame being preferred over all others, md65536. All frames are equally valid, however if an object doesn't gravitationally collapse in its own frame where relativistic effects are not manifested, then it cannot gravitationally collapse in any other frame where relativistic effects are manifested, either. It would certainly be a strange world if you could have a black hole in one frame and not in another.

The only reason I excluded relativistic effects is as not to lead to more confusion along the lines of Sam Bridge's thinking. The length and mass of a relativistic object don't change in its own frame. The density doesn't change. It does not become a black hole. It doesn't become a black hole in any other frame either. And of course you're right charge and angular momentum act as modifiers to the gravitational collapse. They also complicate things even further and I didn't mention them. EM repulsion being billions of billions times stronger than gravitational attraction means even a small charge will resist gravitational collapse further than uncharged mass. These properties are conserved by the BH. But the more I think about it, I realise I could be mistaken. The density at which the earth becomes a black hole is higher density than the density of the sun where it would become a BH. As a matter of fact a large enough mass could gravitationally collapse at a density less than water. Thanks for making me think and keeping me honest. But the main point I was making to Sam is relativistic speeds and effects DO NOT change density.

Please stop using the tiny font. It hurts my old (relatively) and problematic eyes.

Yes md65536, that is exactly what I'm saying. The formation of a black hole depends solely on density. Pack enough mass or energy into a small enough volume and there is no force known which can resist gravitational collapse. (I should clarify that this should happen in its own frame so as to exclude relativistic effects.) And Sam, you're still wrong because you don't seem to realise that the particle in your linear accelerator experiences relativistic effects in frames other than its own. In its own frame it doesn't get heavier or shorter and time passes at a 'normal' rate.

Thank you, imatfaal.

You are mixing up Newtonian gravity with relativistic gravity. Relativistic gravity is explaned by GR and is a geometric theory, not a field based theory. ( Although AJB will probably correct me again that geometry IS the field )

If what you stated about density increase for a near light-speed particle being due to length contraction were true md65536, then there would be nothing to keep a particle from becoming a black hole in one frame and not in its own frame. An irreconcilable difference. Edgard Neuman is right that you cannot consider space only for near light speed objects, you must consider space-time. ACG52 is right about you being wrong, Sam.

The surface of the event horizon can be related to the temperature of a black hole and to its entropy. Entropy is a measure of the increase or decrease of the degrees of freedom of a system, i.e. information. Also the event horizon is the only place where it could be conserved. And you're right, this is attributed to Hawking and a graduate student whose name sound like Beckenstein ( ask AJB he knows who I mean).

Both I and ACG52 will agree that Delta1212 is mistaken as are you Sam. Density is frame INDEPENDANT. In other words, relativistic length contraction and mass increase DO NOT affect the density of an object as they do not change in their own frame. They are only RELATIVE ( to other frames ) effects. Hence the name

Come on Sam. "Did you read what I said? I was suggesting the use of dark energy like a map" ??? Dark energy is the equivalent of vacuum energy/cosmological constant, or it acts exactly like it. How would you map that ? "If photons were so dominant in a period before 380,000 years, why would so few be visible" ??? They ALL are, but most are red shifted down to 2.7 deg K. Do you know what the CMBR is ?