[RascalPuff]

Dear Hearts:
There seems to be a lot of confusion and misunderstandings concerning the nature, meaning and/or import of what is known as the 'event horizon' (sometimes called the 'optical horizon').

I include myself among those who are confused regarding this issue.
As I learned it many years ago, the 'event horizon' is the parameter surrounding a point of observation, where the 'expanding universe' (based on Hubble's constant) overtakes the speed of light. The distance where the relative velocity of light is exceeded, in accordance with the speed of the (spatial) expansion increasing with distance. (This puts a limitation on how far one may proceed with observing the universe - all stations of observation are likewise handicapped with the same limitation: light signals from beyond and outside a given event horizon's boundary no longer reach the observer. With increasing distance, events increasingly slow down, the closer a given light source is to the event horizon; at the parameter there is the same constant signal, and beyond that parameter - event horizon - the light source 'goes out' - there are no signals reaching the observer. Personally, I have no contest with this definition.)

Among the confusions on this issue: is generally founded on the axiom that the speed of light cannot be exceeded.

Whereas, the special theory - to the best of my perhaps out dated knowledge - allows the premise that * the speed of light is constant relative to the source from which it originates.

As far as that goes, allowing that the above *information is correct, I see no contradictiion of the Special Theory with regard to the 'event horizon'. Whereas, there is no small amount of confusion - and related misunderstandings and arguments - surrounding this premise.

Now, when I google 'event horizon' there is much information about black holes and the Schwartzchild radius. 'Dark matter' and 'Dark Energy' has also entered the discussion.

Someone please correct me if I'm wrong, but it is my understanding that the existence of black holes is not a certainty, and, until the '70's, black holes were not even a consideration or controversy and dark matter and dark energy are relative newcomers also; while the 'event horizon' has accompanied the introduction of Hubble's constant since the early 1930's.

Moreover: There seem to be arguments for and against the meaning of Silpher's red shift findings.

Arguments pro and con, whether the (spatial) universe is actually expanding, or whether the red shift is caused by something other than the recession of stellar light sources and galactic systems and clusters of same (quasars).


The only thing I'm sure of is there seems to be a lot of confusion about the mentioned issues and many other considerations contingent to them.

As I understand it, the apparently convuluted (high profile) ensemble of subjects include the works of Silpher, Hubble, Eddington, Lemaitre, de Sitter and Einstein; more recently including Hawking (Certainly there are many other cogent issues - Big Bang, Steady State, Cosmological Constant, hot and cold running dark matter and energy - with as many representatives).

Is there a particular source of information which specifically addresses - the apparently characteristic disparity of - these seemingly entangled issues? Or, is the controversy still embroiled in points and counterpoints (which I tend to think is the case - refer, 'A Can of Wormholes')?

Thank you for reading this missive.

Best regards,
- RP