beecee

Thanks.

Just a correction....C is the symbol for Carbon. "c" is the symbol for the speed of light, or ceritis, the latin word for speed. On your assumption....I'm pretty sure that the speed of light has been tested in a vacuum, and I'm pretty sure the result was "c"...So why do you suggest that this would change in deep space?

Apologies to Marcus.

HI!!! Great to be back.... This question of mine was inspired by a comment from Mordred in the Gravity thread.... Thoughts??

As others have informed you, the only centre of any universe, is that of our observable universe. An Alien on the edge of our observable universe, would also be the centre of his or her observable universe. It has been shown [MAXIMA, Boomerang, WMAP experiments] that our universe is flat to within small tolerances. That flatness does not give us with any certainty, an answer to the question re the universe being infinite or finite, when we consider exotic geometries like a torus. Been off grid for a while fellas and a busy little beaver but havn't as yet kicked the bucket!!!

A more accurate assessment should have been "5 known planets, that may potentially be able to support some basic life, as we know it"

GR tells us that when a sufficiently large enough star uses its available fuel, it will go S/Nova and the remnant turn into a BH...GR tells us that this happens because once the Schwarzchild radius is reach [equal to the EH] further collapse is compulsory, at least up to the quantum level where GR fails us. Also the BB is the evolution of space/time/universe from t+10-43 seconds. Anything before that, or anything at and beyond the quantum/Planck level of a BH, can only ever be speculated on. Some of that speculative talk revolves around our BB being the arse end of a BH in another universe, and BH's in our spacetime, leading to ERB's/wormholes and other universes. Wormholes while predicted in the maths of GR have never been realized, and WH's [white holes] are as far as I know, also in the same boat, with even less speculations about their possibilities. Here is an interesting rundown here...... http://curious.astro.cornell.edu/physics/89-the-universe/black-holes-and-quasars/theoretical-questions/425-what-is-a-white-hole-advanced

Thanks fellas...just some mild confusion and a debate I'm having. All clear now!

https://phys.org/news/2019-09-radio-emission-neutron-star-magnetic.html Radio emission from a neutron star's magnetic pole revealed by General Relativity by Max Planck Society Representation of the precessing pulsar J1906+0746 (with the spin vector in red color) around the total angular momentum vector (blue vector). Two radio beams are emitted above the opposite magnetic poles of the pulsar, along the magnetic axis (grey arrow). As the radio beams cross through our line of sight, we can reconstruct the emission maps of the beams as shown with the circular maps at the edges of the two beams. Credit: Gregory Desvignes (MPIfR Bonn / Paris Observatory) Pulsars in binary systems are affected by relativistic effects, causing the spin axes of each pulsar to change their direction with time. A research team led by Gregory Desvignes from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has used radio observations of the source PSR J1906+0746 to reconstruct the polarised emission over the pulsar's magnetic pole and to predict the disappearance of the detectable emission by 2028. Observations of this system confirm the validity of a 50-year old model that relates the pulsar's radiation to its geometry. The researchers are also able to precisely measure the rate of change in spin direction and find an excellent agreement with the predictions of Einstein's general theory of relativity. more at link.... the paper: https://science.sciencemag.org/content/365/6457/1013 Radio emission from a pulsar’s magnetic pole revealed by general relativity: General relativity reveals pulsar beams Pulsars are rotating neutron stars that emit beams of radio waves along their magnetic poles, seen as regular pulses if the beam points toward Earth. Desvignes et al. monitored a pulsar for more than a decade, observing how its radio pulses vary. General relativity causes precession of the rotation axis, because of the influence of a binary companion. In 2005, two pulses per rotation were visible, one from each magnetic pole, but by 2018 one had precessed out of our line of sight and disappeared. Mapping the radio emission across the magnetic pole determines the beaming angle, the angular region in which a radio observer can detect a pulsar. Science, this issue p. 1013 Abstract: Binary pulsars are affected by general relativity (GR), causing the spin axis of each pulsar to precess. We present polarimetric radio observations of the pulsar PSR J1906+0746 that demonstrate the validity of the geometrical model of pulsar polarization. We reconstruct the (sky-projected) polarization emission map over the pulsar’s magnetic pole and predict the disappearance of the detectable emission by 2028. Two tests of GR are performed using this system, including the spin precession for strongly self-gravitating bodies. We constrain the relativistic treatment of the pulsar polarization model and measure the pulsar beaming fraction, with implications for the population of neutron stars and the expected rate of neutron star mergers.

Speculation is fun, and as Strange has said, reasonable speculation overall. Personally I have often entertained the speculative scenario that the BB is the arse end of a BH in another universe. The important thing to remember, is that while we have no actual evidence of any speculative scenario, it remains speculative and simply hypothetical.

The Earth is actually an oblate spheroid. But tell me, what is North of the North Pole?...Or South of the South pole?

Can you elaborate on that statement please? Does that mean all mass is energy and following on that, that everything is energy? What "properties" does energy have?

Hmmmm, I may throw a spanner into the works on the point of whether spacetime can or cannot exist without the matter energy within....... https://einstein.stanford.edu/content/relativity/a11332.html Can space exist by itself without matter or energy around? "No. Experiments continue to show that there is no 'space' that stands apart from space-time itself...no arena in which matter, energy and gravity operate which is not affected by matter, energy and gravity. General relativity tells us that what we call space is just another feature of the gravitational field of the universe, so space and space-time can and do not exist apart from the matter and energy that creates the gravitational field. This is not speculation, but sound observation". :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: The highlighted part had me confused and so I E-Mailed Sten Odenwald quite a few years ago on that. I received a reply that it was a typographical/publishing error and that it should simply read, "so space and space-time do not exist apart from the matter and energy that creates the gravitational field"

Time of course always passes at one second per second within one's own frame of reference.

Nonsense.

Close up of Eta Carinae....Betelgeuse? Sag A?

Interesting and I tend to agree. Perhaps we need to redefine what nothing is? Perhaps the quantum foam from whence the BB arose is as close to nothing as we can get?

Hmmm, The aspect of the "superforce" was taught to me by a young relativist on a now defunct forum. Also in a book I once read entitled "Superforce"many moons ago, the author from memory Paul Davies? I would say without too much doubt, that you would know more of the gory details then I. I did find the following useful anyway https://www.physicsoftheuniverse.com/topics_bigbang_timeline.html and this.... https://web.njit.edu/~gary/202/Lecture26.html Eras of the Big Bang

And as things get hotter the further we go back, the nature of matter changes....eg: 380,000 years after the BB, matter only existed as Plasma, until temperatures had sufficiently dropped to allow electrons to couple with atomic nuclei to form our first elements of Hydrogen and Helium....3 minutes after the BB, temperatures and pressures were such that quarks started to combine to form protons and neutrons which eventually coupled to form atomic nuclei...at t+10-43 seconds the four known forces existed as one superforce, until conditions were such at t+10-35 seconds, that the superforce started to decouple resulting in false vacuums and phase transitions, with the excesses of energy going into creating our first fundamental particles of electrons and quarks.

The BB is a theory of how our "observable" universe evolved from a hotter, denser state, to the conditions we see today. http://www.astro.ucla.edu/~wright/infpoint.html "The Universe was not concentrated into a point at the time of the Big Bang. But the observable Universe was concentrated into a point. The distinction between the whole Universe and the part of it that we can see is important" more at link.....

Change [of distance] occurs in time. Time is not specifically a result of change. imho.

There is no universal now.

Your beliefs are neither here nor there. Science tells us that at this time, we simply cannot say with any certainty, whether the universe/spacetime is finite or infinite. You should also note that at one time, space and time were seen as "absolute" and it was counter intuitive [anti logic] to claim otherwise. We know better now.

All potential theoretical models will be challenged. That's part and parcel of the scientific method. If you did what you claim [completed it] it would be accepted by mainstream. Unless of course you are one of the hundreds of claims by "would be's if they could be's" that mainstream scientists are just simply too stagnated and recalcitrant in their thinking. I don't accept that and simply apply the scientific method in that all potential theories must run the gauntlet, to gain acceptance as an incumbent model. Not sure about that description. I see the ever increasing expansion rate over large scales, with spidery web like structures forming under gravitational attraction, increasing the voids in between the spider web like structures. Not really, but it appears you have answered it in your claim you are trying to complete GR. Albert also spent the greater part of his life looking for a "unified field theory"

If the expansion is overcome by mass/energy densities and gravity, then it cannot occur.