Chrispen Evan

only particles without mass travel a lightspeed. neutrinos have mass, albeit small.

and imagination without knowledge is just dreaming.

the universe, the big one not just the observable, according to theory, doesn't have a boundary. this would imply that there is an "outside". for example, and as much as i dislike the balloon analogy, a balloons suface when being inflated gets larger but has no boundary. we must be careful to consider only the surface.

the shape of the observable universe is spherical. the universe that this bit is embedded in has no boundary so has no "shape".

shape doesn't always mean what we think it does in everyday language. for instance a donut is the same shape as a mug and also as a human. in topology all these are the same shape. meaning they can be bent and manipulated into each other. all have one hole. so topologically speaking if we drew a large triangle in space and it resembled what a triangle drawn on, say, the saddle shape then our universe would be saddle shaped. this doesn't mean the actual shape. our universe is thought to be flat and infinite according to WMAP results.

look up Simulation Argument. http://www.simulation-argument.com/ here's a start.

this is a common misconception. Hoyle was giving a radio interview and he wanted to get across what the current theory proposed. to be dramatic he said it was like a big bang. he wasn't being derogatory at all. this is a subject that i try to correct whenever possible so no offence intended. for all his faults in not accepting the BB model until near the end Hoyle was a great scientist.

canis majoris is a red supergiant, so while its mass is only x30 our sun its density would be a lot less. http://en.wikipedia.org/wiki/VY_Canis_Majoris It has an average density of 5 to 10 mg/m3. http://www.universetoday.com/94252/characteristics-of-the-sun/ Density of the Sun: 1.622 x 105 kg/m3

if the sparkler material contained powdered aluminium then you would get a more energetic bang.

you would imagine so. i don't think you'd get two large masses orbiting each other and orbiting the star as well. i think that set-up may be unstable.

roughly yes, disregarding their own proper motion. there was less space between them though.

maybe not but that is the "common" terms used. and i try to make it comprehensible to the level of the question. clarification is always appreciated though.

this is due to the inflation period which happened a very short time after T=0. this rapid expansion resulted in space expanding faster than light. http://www.lifesci.sussex.ac.uk/home/John_Gribbin/cosmo.htm

it isn't. if Earth was compressed down a couple of centimetres in diameter then it would form a BH. it's mass wouldn't have changed though. http://en.wikipedia.org/wiki/Escape_velocity the explosion of the star compressed the matter to get over the atomic forces keeping the particles separate. http://en.wikipedia.org/wiki/Supernova the singularity is just a name we give to a region where our current theories no longer can model successfully. http://en.wikipedia.org/wiki/Gravitational_singularity

this is not how i understand the process. two virtual particles are produced. one escapes and becomes real. the other crosses the event horizon, and to keep the balance as you have a real particle escaping, takes mass from the Black Hole and so will, over time, cause the BH to evaporate. or something like that.

you can't get a light source that will emit one exact frequency. theoretically yes but practically no. the atom that emits the light is moving so there will be doppler shift. the apparatus measuring the emitted light will move giving more doppler shift. this is due to the kinetic energy in the system causing random motion. also to measure an exact frequency you'd need and infinite number of wave cycles to measure.

the cmbr is the light from the surface of last scattering, about 370 000 years after the BB. it is when the universe became transparent to light. http://en.wikipedia.org/wiki/Cosmic_microwave_background_radiation

thanks Ophiolite. I'm Boris2 on sciforums so we've "met" before.

http://www.biodiversitylibrary.org/item/51467#page/53/mode/1up Joly, J. 1899. An estimate of the geological age of the earth. Scientific Transactions of the Royal Dublin. Society, New Series, 7, 23-66. method. looked up the royal dublin society to see if copies were online. then found the edition and page numbers of the paper. Joly, J. (1899). An estimate of the geological age of the earth Scientific Transactions of the Royal Dublin. Society google search terms.

which is more correct, to say massive objects can't travel at the speed of light or that massive objects can't be accelerated to the speed of light? i realise there is a problem with the latter but just would like a clarification. thanks

the inner horizon is called the Cauchy Horizon. http://en.wikipedia.org/wiki/Cauchy_horizon http://en.wikipedia.org/wiki/Cauchy_surface need mathematical understanding, which i don't have. http://www.uncletaz.com/library/scimath/bhint.html no maths. and i believe reliable