MigL

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 ?

Your interpretation of entanglement is faulty. Information propagation is limited to the speed of light. Information is believed to be stored on the event horizon of a black hole and conserved. This conservation law is a quantum mechanical consequence while black holes are currently understood as classical GR consequence. We await the unification of the two to get a better understanding of these effects.

So the LHC has verified the existence of a new type of hadron consisting of two quarks and two anti-quarks whereas QCD previously predicted that the only possible arrangements were either a three quarks ( or anti-quarks ) grouping , or a quark/anti-quark grouping. What does this mean for QCD ? Does it need to be scrapped ? Does it need modifying ? Is this of no significance, just an embarassement for Murray Gell-Mann ?

The only reasonable argument I've ever seen for negative energy/mass is due to virtual particles at the event horizon of a black hole. For a brief instant of time the HUP allows for the borrowing of energy to create a virtual particle pair. If one of the particles falls into the event horizon while the other goes free and becomes real ( Hawking radiation ), they obviously cannot recombine to repay the borrowed energy. The black hole is then 'on the hook' for this negative energy and must give up some of its own energy/mass to repay the debt. In effect the black hole has ingested a particle but has lost mass. This is only possible if the ingested particle had negative energy. The casimir effect ( arguably ) and the expansion/inflation of the universe, on the other hand, have to do with negative pressure related to vacuum energy and false zero levels of this energy.

Maybe I misunderstood you as much as you misunderstood me. I wasn't referring to political parties as tody's repiblicans certainly aren't Eisenhower's republicans, but rather the labels conservative or liberal. I for one have no use for them.

No.

Totally agree with you Studiot. The ear is sensitive to phase difference so we have two for comparison purposes, cetainly not to absolute phase. How could it be since an ear is the equivalent of an inverse speaker, i.e. a drum which converts translation/vibration to bioelectric signals ? And as you say the speaker experiment demonstrates this very well.

You guys do realise that the emitted power of a quasar while extremely large, is dwarfed in comparison to the power of the black hole which generates the jets. It would be like using a nuclear weapon to fire a bullet. Is there any sense in weaponising the bullet ????

We probably share more views than that Lizzie, as I said, the labels are what separate and polarize people. I don't consider miself conservative or liberal but try to live my life according to the best ( to me anyway ) principles of both. As much as conservatives are generally looked down on or considered fools, almost everyone bases their household budget on conservative principles,. Yet when we pool our money into a government for a collective purpose, all of a sudden it becomes okay to spend and borrow like drunken sailors. That is obviously wrong, so at least one conservative principle is justified. There are others just as there are liberal principles which are beneficial. I just find it odd that some people equate conservatives with evil people or fools. Thanks for an interesting discussion, and I did like your grandfather's quote. But as davidivad has said, maybe we should get back on topic.